A Phase 1 dose escalation and expansion trial of the next-generation oral SERD camizestrant in women with ER-positive, HER2-negative advanced breast cancer: SERENA-1 monotherapy results

BACKGROUND

SERENA-1 (NCT03616587) is a Phase 1, multi-part, open-label study of camizestrant in pre- and post-menopausal women with ER+, HER2- advanced breast cancer. Parts A and B aim to determine the safety and tolerability of camizestrant monotherapy and define doses for clinical evaluation. Patients and Methods Women aged 18 years or older with metastatic or recurrent ER+, HER2- breast cancer, refractory (or intolerant) to therapy were assigned 25 mg up to 450 mg once daily (QD; escalation) or 75, 150, or 300 mg QD (expansion). Safety and tolerability, anti-tumor efficacy, pharmacokinetics, and impact on ESR1m circulating tumor (ct)DNA levels were assessed.

RESULTS

By 9 March 2021, 108 patients received camizestrant monotherapy at 25-450 mg doses. Of these, 93 (86.1%) experienced treatment-related adverse events (TRAEs), 82.4% of which were grade 1 or 2. The most common TRAEs were visual effects (56%), (sinus) bradycardia (44%), fatigue (26%), and nausea (15%). There were no TRAEs grade 3 or higher, or treatment-related serious adverse events (TRSAEs) at doses ≤150 mg. Median tmax was achieved ∼2-4 hours post-dose at all doses investigated, with an estimated half-life of 20-23 hours. Efficacy was observed at all doses investigated, including in patients with prior CDK4/6 inhibitor and/or fulvestrant treatment, with and without baseline ESR1 mutations, and with visceral disease, including liver metastases.

CONCLUSIONS

Camizestrant is a next-generation oral SERD and pure ER antagonist with a tolerable safety profile. The pharmacokinetics profile supports once-daily dosing, with evidence of pharmacodynamic and clinical efficacy in heavily pre-treated patients, regardless of ESR1m. This study established 75, 150 and 300 mg QD doses for Phase 2 testing (SERENA-2, NCT04214288 and SERENA-3, NCT04588298).

A222 BILIARY ATRESIA IN BRITISH COLUMBIA: THE ROLE OF REFERRAL AGE AND DIAGNOSITIC EVALUATION ON OUTCOME

Background

Biliary atresia (BA), a newborn liver disease, is the leading cause of cirrhosis and liver-related death in children and the most common indication for pediatric liver transplantation (LT). The current standard of BA care is sequential surgery with an initial Kasai hepatoportoenterostomy (KP), followed by LT for those who progress to liver failure. Survival with native liver (SNL) correlates to infant age at KP with best outcome at early KP at <30 days of age. Novel screening tests and diagnostic algorithms have been proposed, however the variability of clinical presentation and lack of a diagnostic test challenge early diagnosis and timely KP.

Aims

To assess age at BA presentation and subsequent investigations to the timing of KP and outcome.

Methods

A retrospective study of all BA cases referred to BC Children’s Hospital January 1, 2000-December 31, 2018. Data collection included age at referral, clinical presentation, laboratory and imaging studies, age at KP and LT. SNL and overall survival rates were determined. Descriptive statistics and data analyses using SSPS were applied.

Results

In this 19-year study, there were 48 cases (58% female) of BA in BC (1:17,000 live births). KP was performed in 41 patients and 7 had primary LT. Following the initial KP, 23 cases had LT. Median age at presentation decreased from 55 to 42 days after introduction of the BC BA stool card screening program in 2014. The Median (IQR) age at KP was 62 days (48–87). Median delay from the age at first encounter to the KP was 10 days (4–21); early referral (youngest 3^rd of cohort) had a mean delay to KP of 25 days (15–40) compared with the late group (oldest 3^rd of cohort) with median delay to KP of 5 days (1–8). There were 2.4 and 1.4 investigations/patient before undergoing KP in the youngest and oldest age at presentation cohorts. HIDA scan was done in 41% and 19% of the youngest and oldest presentation cohorts respectively. Median LT age was 9.6 months (8-13months). Median age at KP for patients who received LT was 77 days (53–92), compared to 52 days (41–79) in those without LT (p=0.08). All KPs were completed by 7 surgeons, each completing 1- 10 KPs. Overall patient survival and SNL were 98% and 37.5%.

Conclusions

In this cohort, SNL rates were below SNL rates in other national studies. SNL rates were higher in patients who underwent KP at a younger age, and early findings from a provincial screening program show a shift in age at presentation, potentially owing in part to increased community awareness of BA. A diagnostic algorithm that accounts for age at presentation is needed achieve timely KP.

Funding Agencies

None

Disseminated Saksenaea infection in an immunocompromised host associated with a good clinical outcome: a case report and review of the literature

Background

Saksenaea species (spp.) are uncommon causes of mucormycosis but are emerging pathogens mostly associated with trauma and soil contamination often in immunocompetent hosts. Due to lack of sporulation in the laboratory, diagnosis and susceptibility testing is difficult so optimal treatment regimens are unknown.

Case presentation

A 67 year-old man from the Northern Territory in Australia, with a history of eosinophilic granulomatosis with polyangiitis, developed disseminated Saksenaea infection after initially presenting with symptoms consistent with bacterial pyelonephritis. Despite a delay in diagnosis; with aggressive surgical management and dual therapy with amphotericin B and posaconazole, he survived.

Conclusions

We describe an unusual case of disseminated infection with a favourable outcome to date.

Burkholderia pseudomallei multi-centre study to establish EUCAST MIC and zone diameter distributions and epidemiological cut-off values

OBJECTIVES

Melioidosis, caused by Burkholderia pseudomallei, requires intensive antimicrobial treatment. However, standardized antimicrobial susceptibility testing (AST) methodology based on modern principles for determining breakpoints and ascertaining performance of methods are lacking for B. pseudomallei. This study aimed to establish MIC and zone diameter distributions on which to set epidemiological cut-off (ECOFF) values for B. pseudomallei using standard EUCAST methodology for non-fastidious organisms.

METHODS

Non-consecutive, non-duplicate clinical B. pseudomallei isolates (9-70 per centre) were tested at eight study centres against eight antimicrobials by broth microdilution (BMD) and the EUCAST disc diffusion method. Isolates without and with suspected resistance mechanisms were deliberately selected. The EUCAST Development Laboratory ensured the quality of study materials, and provided guidance on performance of the tests and interpretation of results. Aggregated results were analysed according to EUCAST recommendations to determine ECOFFs.

RESULTS

MIC and zone diameter distributions were generated using BMD and disc diffusion results obtained for 361 B. pseudomallei isolates. MIC and zone diameter ECOFFs (mg/L; mm) were determined for amoxicillin-clavulanic acid (8; 22), ceftazidime (8; 22), imipenem (2; 29), meropenem (2; 26), doxycycline (2; none), tetracycline (8; 23), chloramphenicol (8; 22) and trimethoprim-sulfamethoxazole (4; 28).

CONCLUSIONS

We have validated the use of standard BMD and disc diffusion methodology for AST of B. pseudomallei. The MIC and zone diameter distributions generated in this study allowed us to establish MIC and zone diameter ECOFFs for the antimicrobials studied. These ECOFFs served as background data for EUCAST to set clinical MIC and zone diameter breakpoints for B. pseudomallei.

Abstract OT1-06-03: The plasmaMATCH trial: A multiple parallel cohort, open-label, multi-centre phase II clinical trial of ctDNA screening to direct targeted therapies in patients with advanced breast cancer (CRUK/15/010)

Introduction

Circulating tumour DNA (ctDNA) is found in the plasma of over 90% of patients with advanced breast cancer (BC). Screening for the presence of mutations in ctDNA provides a current assessment of the genetic profile of the patient's recurrent BC. The plasmaMATCH trial is designed to assess the potential of ctDNA screening to direct targeted therapies in patients with advanced breast cancer.

Methods

plasmaMATCH is a multi-centre phase IIa umbrella trial platform of ctDNA screening and a therapeutic trial. The study will screen 1000 women with advanced breast cancer, who have received prior systemic treatment in the advanced setting, with digital PCR ctDNA assays for hotspot mutations in ESR1, HER2, AKT1, and PIK3CA, with HER2 copy number assessment, in a central laboratory. The study will recruit from up to 50 sites in the UK. Patients with mutations identified will enter the matching treatment cohort, ESR1 – extended dose fulvestrant 500mg every two weeks, HER2 – neratinib +/- fulvestrant, AKT1 – AZD5363 +/- fulvestrant.

Mutation prevalence is presented with corresponding exact 95% confidence intervals (CIs) both overall and excluding 14 patients who were known to have mutations from a prior screening program. Patients with more than one mutation are included once in each relevant row.

Results

We report the results of prospective ctDNA mutation testing in the first 92 patients. plasmaMATCH opened to recruitment on 15/12/2016. As of 08/06/2017, 120 patients have been registered for ctDNA screening from 7 UK centres, of which 92 have ctDNA screening results available:

plasmaMATCH ctDNA screening resultsMutationPrevalence (95% CI)Prevalence excluding 14 patients with known mutations (95% CI)ESR134/92: 37% (27%-48%)26/78: 33% (23%-45%)HER25/90: 6% (2%-12%)2/76: 3% (0%-9%)AKT17/92: 8% (3%-15%)4/78: 5% (1%-13%)PIK3CA*22/92: 24% (16%-34%)21/78: 27% (18%-38%)*No corresponding plasmaMATCH treatment cohort

14 patients had more than one mutation detected (10 ESR1+PIK3CA, 3 ESR1+AKT1, 1 ESR1+ +HER2+AKT1). ctDNA results were reported in a median of 8 working days.

Of the 40 patients with one or more actionable mutation, 15 have entered a cohort, 16 are being screened for entry into a cohort, 5 are currently receiving further systemic treatment prior to cohort entry and 4 will not enter a cohort. One additional patient has entered a treatment cohort on the basis of a mutation detected in an alternative tumour sequencing initiative.

Conclusions

plasmaMATCH ctDNA demonstrates the feasibility and accuracy of ctDNA testing as a screening tool for patients with advanced BC, with a high rate of subsequent recruitment into matching therapeutic trials.

Citation Format: Turner N, Bye H, Kernaghan S, Proszek P, Fribbens C, Moretti L, Morden J, Snowdon C, Macpherson I, Wardley A, Roylance R, Baird R, Bliss J, Ring A. The plasmaMATCH trial: A multiple parallel cohort, open-label, multi-centre phase II clinical trial of ctDNA screening to direct targeted therapies in patients with advanced breast cancer (CRUK/15/010) [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT1-06-03.

Mechanical Ventilation and Extracorporeal Membrane Oxygenation as a Bridging Strategy to Lung Transplantation: Significant Gains in Survival

Mechanical ventilation (MV) and extracorporeal membrane oxygenation (ECMO) are increasingly used to bridge patients to lung transplantation. We investigated the impact of using MV, with or without ECMO, before lung transplantation on survival after transplantation by performing a retrospective analysis of 826 patients who underwent transplantation at our high-volume center. Recipient characteristics and posttransplant outcomes were analyzed. Most lung transplant recipients (729 patients) did not require bridging; 194 of these patients were propensity matched with patients who were bridged using MV alone (48 patients) or MV and ECMO (49 patients). There was no difference in overall survival between the MV and MV+ECMO groups (p = 0.07). The MV+ECMO group had significantly higher survival conditioned on surviving to 1 year (median 1,811 days ([MV] vs. not reached ([MV+ECMO], p = 0.01). Recipients in the MV+ECMO group, however, were more likely to require ECMO after lung transplantation (16.7% MV vs. 57.1% MV+ECMO, p < 0.001). There were no differences in duration of postoperative MV, hospital stay, graft survival, or the incidence of acute rejection, renal failure, bleeding requiring reoperation, or airway complications. In this contemporary series, the combination of MV and ECMO was a viable bridging strategy to lung transplantation that led to acceptable patient outcomes.

Abstract P6-12-03: A phase I study of AZD9496, a novel oral, selective estrogen receptor degrader (SERD) in women with estrogen receptor positive, HER-2 negative advanced breast cancer (ABC)

Background AZD9496 is a potent orally bioavailable ER antagonist and degrader that has shown antitumor efficacy in a range of preclinical xenograft models including ESR1wild-type tamoxifen-resistant and long term estrogen deprived models and an ESR1 mutant model.

Methods This is a phase I, open label global multicenter study in women with ER+ HER2–ve BC either metastatic or locoregionally recurrent, not amenable to treatment with curative intent. Patients are post-menopausal, or pre-menopausal women receiving LHRH agonist therapy, with disease progression after ≥6 months endocrine therapy for ER+ BC (no limit on number of prior endocrine therapies; ≤2 prior chemotherapies in advanced setting). The primary objective is to determine the safety and tolerability of AZD9496. Cohorts of 3-6 patients received daily oral therapy and dose limiting toxicities (DLTs) occurring in cycle 1 (28 days) were assessed. Patients are dosed until MTD (defined as ≤1/6 patients with a DLT) or maximum feasible dose (MFD) is reached. Key secondary objectives include determination of single and multiple dose pharmacokinetics (PK), and preliminary antitumor efficacy. ER target modulation by protein and gene expression is evaluated in circulating tumor cells and paired tumor biopsies.

In addition to the dose escalation phase, expansion cohort(s) in patients with or without ESR1 mutations can be enrolled to examine the safety, tolerability, PK and biological activity of AZD9496 further.

Results Preliminary data as of 30th April 2016: 45 patients (median age 62 (range 41-83); 38 post-menopausal, 7 pre/perimenopausal; visceral metastases 76%, prior fulvestrant 25/45) received AZD9496 in 7 dose escalation cohorts: 20mg QD n=4, 40mg BID n=6, 80mg BID n=5, 150mg BID n=6, 250mg BID n=6, 400mg BID n=6, 600mg BID n=6 and also a 250mg BID expansion cohort n=6. The majority of adverse events (AEs) were grade 1 or 2; the most common treatment-related AEs (≥10%) have been diarrhoea (33%), fatigue (27%), nausea (22%), upper abdominal pain (13%) and increased liver function tests (13%). Six patients had treatment-related grade 3 AEs, 5 of which were manageable with dose interruption +/- dose reduction. Specifically, three had DLTs: grade 3 increased AST/ALT/GGT-150mg BID, serious adverse reaction (SAR) leading to withdrawal; grade 3 diarrhoea and grade 3 increased AST/ALT/GGT-400mg BID, SAR, manageable with dose reductions; grade 3 diarrhoea 600mg BID, manageable with dose reduction. The MTD/MFD has not been reached.

Following the first dose up to 400mg the AZD9496 exposure increased in reasonable proportion to increasing dose. At 600mg a more than dose-proportional increase in exposure was observed. Evidence of reduced ER and Ki67 has been observed in on-study biopsies at 150mg BID and above. 10 subjects received treatment for &gt;3-&lt;6 months (5 ongoing, 5 discontinued),4 subjects &gt;6-&lt;12 months (3 ongoing, 1 discontinued), 3 subjects ≥1 year (2 ongoing, 1 discontinued).

Conclusions AZD9496 has a tolerable safety profile, evidence of PD biomarker modulation and prolonged stabilisation of disease in women with heavily pre-treated ER+ve ABC.

Citation Format: Hamilton E, Patel M, Armstrong A, Baird R, Jhaveri K, Hoch M, Morgan S, Dowdall T, Schiavon G, Klinowska T, Weir H, Bujac S, Nash T, Im S-A. A phase I study of AZD9496, a novel oral, selective estrogen receptor degrader (SERD) in women with estrogen receptor positive, HER-2 negative advanced breast cancer (ABC) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-12-03.

Abstract P4-21-08: A phase I/II of S-222611, a reversible EGFR and HER2 inhibitor, combined with trastuzumab +/- chemotherapy in patients with HER2-positive metastatic breast cancer

Background: S-222611, an oral, reversible EGFR and HER2 inhibitor, has been shown to be well-tolerated as monotherapy at a dose of 800mg daily with good anti-tumor activity in patients previously treated with other anti-HER2-based regimens. This study evaluated the tolerability and safety of daily oral administration of S-222611 (S) in combination with trastuzumab (T), trastuzumab + vinorelbine (T+V) and trastzumab + capecitabine (T+C) in HER2-positive (HER2+) metastatic breast cancer (MBC) with or without brain metastases.

Methods: This study was performed as a 3+3 dose escalation followed by expansion to examine the tolerability and safety of S in combination with T, T+V and T+C in Arms A, B and C, respectively. S was administered orally once daily, starting at a dose of 400mg in Arm A, and 200mg in Arms B and C. The dosing of T was 8mg/kg loading followed by 6mg/kg or fixed dose of 600mg subcutaneously every 21 days as recommended. V was administered at 60mg/m2 orally on Day 1 and 8 of a 21-day cycle, and C 1000mg/m2 orally daily for 14 days followed by a 7-day rest period. All patients had HER2+ MBC and were required to have progressed following at least one prior line of anti-HER2 therapy. Prior treatments with V and C were permitted. Anti-diarrhea prophylaxis with loperamide was not required.

Results: A total of 45 patients were enrolled. All patients had received prior anti-tumor regimens including T (n=45), T-DM1 (n=26), pertuzumab (n=9) and lapatinib (n=12). The clinically recommended doses of S at which most adverse events were manageable,were determined as:600mg in Arm A, 200mg in Arm B and 400mg in Arm C. Dose limiting toxicities included Grade 3 diarrhea for Arm A; and Grade 4 neutropenia, Grade 3 Hypokalemia and Hypophosphatemia for Arm B. As of 13 May 2016, treatment is ongoing in 2 patients. No other Grade 4 AEs related to S-222611 have been observed. Grade 3 bilirubin elevation was observed in 5/45 patients, probably due to transporter (UGT1A1) inhibition, while no G3/4 liver dysfunction was reported. RECIST partial responses (PR) were observed in 6 of 9 patients in Arm A and 5 of 9 patients in Arm C, at respective clinically recommended doses. Nine of 45 patients had brain metastases; 4 of these patients showed RECIST PR including an intracranial tumor response in one patient (400mg in Arm C) who had prior treatments with paclitaxel, T+C, T-DM1 and V after diagnosis of BM.

Conclusions: The clinically recommended doses of S-222611 combined with T, T +V and T+C were determined for further clinical studies. Clinical benefit (PR and SD &gt;6 month) was seen with each combination even in heavily pre-treated HER2+ MBC patients.

Summary of the safety and efficacy of S-222611 (S) combination. Dose (mg)nDLT (1st cycle)G3 Diarrhea during study (N of patients)RECIST tumor response, PR n/ SD ≥6M nORR n (%)CBR n (%)Arm A: S + T4005010/10/5 (0%)1/5 (20%)Arm A: S + T6009036/06/9 (67%)6/9 (67%)Arm A: S + T8007141/11/7 (14%)2/7 (29%)Arm B: S + T + V2005020/40/5 (0%)4/5 (80%)Arm B: S + T + V4002211/01/2 (50%)1/2 (50%)Arm C: S + T + C2004010/10/4 (0%)1/4 (25%)Arm C: S + T + C4009025/05/9 (56%)5/9 (56%)Arm C: S + T + C6004022/12/4 (50%)3/4 (75%)

Citation Format: Rafii S, Macpherson I, Baird R, Saggese M, Spiliopoulou P, Kumar S, Italiano A, Bonneterre J, Campone M, Cresti N, Posner J, Takeda Y, Arimura A, Spicer J. A phase I/II of S-222611, a reversible EGFR and HER2 inhibitor, combined with trastuzumab +/- chemotherapy in patients with HER2-positive metastatic breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-21-08.

A pilot investigation of feeding problems in children with esophageal atresia

While many long-term complications of esophageal atresia (EA) have been well investigated, little is known about feeding difficulties in children after surgical correction of EA and its impact on caregivers. This study investigates the feeding behaviors of children with EA through a validated feeding questionnaire. The Montreal Children's Hospital Feeding Scale (MCH-FS) was filled out by the primary caregiver during patient follow-up visits in the multidisciplinary EA clinic. Demographic information, EA subtype, associated anomalies and outcomes were recorded. Results were compared between groups and to a normative sample. Thirty caregivers have completed the MCH-FS; 26 patients had type C atresia (86.7%). In comparison to controls, 17.5% of EA cases are one standard deviation above the mean feeding difficulty score, while 6.7% (n = 2) cases are greater than two standard deviations above normative values. Typical EA patients (type C who were not born <30 weeks) had mean MCH-FS scores in the subclinical range, whereas one extremely premature child and the patients with non-type C EA (n = 4) all had scores in the severe range. Feeding difficulties of patients with typical EA appear mild. Likely explanations include the use of early protocolized care and intensive multidisciplinary care in follow up. Nonetheless, patients with complicated EA (non-type C) and their caregivers tend to experience significant feeding difficulties. Early targeted care may be required for this patient subset, and additional cases will be investigated to confirm these preliminary findings and explore further risk factors of feeding problem in this cohort.

Evaluation of aortopexy in the management of severe tracheomalacia after esophageal atresia repair

Severe tracheomalacia (TM) is a difficult problem in esophageal atresia (EA) patients. We reviewed our experience with aortopexy and other interventions for severe TM in this population. With review ethics board approval, a retrospective review of TM in postoperative EA patients was conducted (1989-2010). Demographics, perinatal, and surgical information regarding EA repair was collected. TM infants were analyzed for symptomatology, clinical severity, investigations, interventions, and outcomes. Data are presented as proportions or median(range). One hundred and thirty-two EA patients were reviewed. Most had type C atresia (87.3%), and 18 patients (13.6%) died. Twenty-five patients (18.9%) had TM of whom five (20%) died. Median symptom onset was 18 days (0-729) after EA repair, with stridor (64%) or retractions/distress (44%) being most frequent. Four and two patients had airway obstruction or cardiorespiratory arrest, respectively. Median time from symptom onset to investigations was 11 days; these were most commonly rigid bronchoscopy (56%) and fluoroscopy (36%). Ten patients (40%) had severe TM on bronchoscopy. Six underwent aortopexy, one fundoplication, and three were treated medically. Length of hospital stay (LOS) post-aortopexy was 13 days (5-60), and ventilation time was 2 days (0-9). LOS was 60.5 (1-69) days postdiagnosis in non-aortopexy patients. Readmission rates for respiratory issues were significantly less in the aortopexy (median 0 vs. 5; P = 0.048) group over 2-year follow up after discharge. Complications of aortopexy included transfusion (1) and temporary diaphragmatic paresis (1), and one mortality secondary to severe congenital cardiac anomalies. Our experience suggests that aortopexy is safe and effective for the treatment of severe TM. It is associated with reduced LOS compared with other treatment strategies and few complications or long-term sequelae.

Phase 1 dose-escalation study of S-222611, an oral reversible dual tyrosine kinase inhibitor of EGFR and HER2, in patients with solid tumours

BACKGROUND

S-222611 is a reversible inhibitor of EGFR, HER2 and HER4 with preclinical activity in models expressing these proteins. We have performed a Phase 1 study to determine safety, maximum tolerated dose (MTD), pharmacokinetic profile (PK) and efficacy in patients with solid tumours expressing EGFR or HER2.

PATIENTS AND METHODS

Subjects had advanced tumours not suitable for standard treatment, expressing EGFR or HER2, and/or with amplified HER2. Daily oral doses of S-222611 were escalated from 100mg to 1600 mg. Full plasma concentration profiles for drug and metabolites were obtained.

RESULTS

33 patients received S-222611. It was well tolerated, and the most common toxicities, almost all mild (grade 1 or 2), were diarrhoea, fatigue, rash and nausea. Only two dose-limiting toxicities occurred (diarrhoea and rash), which resolved on interruption. MTD was not reached. Plasma exposure increased with dose up to 800 mg, exceeding levels eliciting pre-clinical responses. The plasma terminal half-life was more than 24h, supporting once daily dosing. Responses were seen over a wide range of doses in oesophageal, breast and renal tumours, including a complete clinical response in a patient with HER2-positive breast carcinoma previously treated with lapatinib and trastuzumab. Four patients have remained on treatment for more than 12 months. Downregulation of pHER3 was seen in paired tumour biopsies from a responding patient.

CONCLUSIONS

Continuous daily oral S-222611 is well tolerated, modulates oncogenic signalling, and has significant antitumour activity. The recommended Phase 2 dose, based on PK and efficacy, is 800 mg/day.

Changes in the clinical and epidemiological features of group A streptococcal bacteraemia in Australia's Northern Territory

OBJECTIVE

Invasive group A streptococcus (iGAS) disease is an important cause of mortality globally. The incidence of iGAS in Australia's tropical Northern Territory (NT) has been previously reported as 32.2/100 000 in Indigenous people for the period 1991-1996. We aimed to measure the incidence and severity of iGAS disease in the NT since this time.

METHODS

We collected demographic data for all GAS blood culture isolates over a 12-year period (1998-2009) from the three hospital laboratories serving the tropical NT. We then collected detailed clinical information from hospital records and databases for the subset of these patients who were admitted to Royal Darwin Hospital during 2005-2009.

RESULTS

There were 295 confirmed cases of GAS bacteraemia over the study period, with a mean (SD) age of 42.1 (22.0) years, and 163 (55.0%) were male. The annual age-adjusted incidence was 15.2 (95% CI 13.4-16.9)/100 000 overall and 59.4 (95% CI 51.2-67.6) in Indigenous Australians. For 2005-2009, there were 123 cases with the most common focus of infection being skin/soft tissue [44 (35.6%)]; 29 patients (23.6%) required intensive care unit admission and 20 (16.3%) had streptococcal toxic shock syndrome. Antecedent sore throat or use of non-steroidal anti-inflammatory drugs was rare, but current or recent scabies, pyoderma and trauma were common.

CONCLUSION

The incidence and severity of iGAS are high and increasing in tropical northern Australia, and urgent attention is needed to improve surveillance and the social determinants of health in this population. This study adds to emerging data suggesting increasing importance of iGAS in low- and middle-income settings globally.

First Report of Geosmithia morbida in North Carolina: The Pathogen Involved in Thousand Cankers Disease of Black Walnut

In the past decade, black walnut (Juglans nigra) trees throughout western North America have suffered from widespread branch dieback and canopy loss, causing substantial tree mortality (2,3). The fungus, Geosmithia morbida, vectored by the walnut twig beetle (WTB), Pityophthorus juglandis, has been associated with this devastating disease known as Thousand Cankers Disease (TCD) (2,3). In August of 2012, branch samples from TCD symptomatic black walnut trees (5 to 10 cm in diameter and 15 to 30 cm long) were collected on the North Carolina side of the Great Smoky Mountain National Park (GRSM) in Cataloochee Cove (35°37.023' N, 83°07.351' W) and near the Big Creek Campground (35°45.290' N, 83°06.473' W), in Haywood County. Five symptomatic trees near the Big Creek Campground and three from Cataloochee Cove displayed typical TCD signs including progressive crown thinning, branch flagging, and branch dieback; however, insect holes were not observed. Samples were double bagged in Ziploc plastic bags, sealed in a 19-liter plastic bucket, and transported to the University of Tennessee. Outer bark was removed from the samples and small, elliptical, necrotic cankers were observed. Wood chips (3 to 4 mm²) from cankers were excised and placed on 1/10 strength potato dextrose agar amended with 30 mg/liter streptomycin sulfate and 30 mg/liter chlortetracycline HCL and incubated on a 12-h dark/light cycle at 22°C for 5 to 7 days. Fungal isolates were tentatively identified as G. morbida by using culture morphology, and characteristics of conidiophores and conidia (2). The isolated fungus from the Cataloochee Cove location was grown in 1/10 strength potato dextrose broth at room temperature for 2 weeks. Isolates from Big Creek Campground were contaminated and were not analyzed further. Fungal colonies were tan to light yellow. Conidia were tan, subcylindrical, and catenulate. Conidiophores were multibranched, verticillate, and verrucose. To verify the morphological data, DNA was extracted from fungal mycelia using DNeasy Plant Mini Kit (Qiagen, Valencia, CA) according to the manufacturer's published protocol. Isolates from Cataloochee Cove were characterized using ITS1 and ITS4 universal primers (4). The putative G. morbida isolate (GenBank Accession No. KC461929) had ITS sequences that were 100% identical to the G. morbida type isolate CBS124663 (FN434082.1) (2). Additionally, fungal DNA from Cataloochee Cove was amplified using G. morbida-specific microsatellite loci (GS04, GS27, and GS36) (1). PCR products were analyzed with the QIAxcel Capillary Electrophoresis System (Qiagen) and were similar to those previously published (2). To date, all confirmed cases of TCD in the native range of black walnut have been in urban areas, along rural roadsides and/or fence rows. The report in North Carolina is the first finding of G. morbida, the causal agent of TCD, in a forest setting. References: (1) D. Hadziabdic et al. Conserv. Genet. Resources 4:287, 2012. (2) M. Kolarik et al. Mycologia 103:325, 2011. (3) N. Tisserat et al. Plant Health Progr. doi:10.1094/PHP-2011-0630-01-BR, 2011. (4) T. J. White et al. Page 315 in: PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, CA, 1990.

Human T-cell lymphotropic virus type 1 exposures following blood-borne virus incidents in central Australia, 2002-2012

We retrospectively audited hospital occupational exposure events over a 10-year period, in a human T-cell lymphotropic virus type 1 (HTLV-1)-endemic area of Central Australia, and report on 53 individuals exposed to HTLV-1 with no transmissions documented (95% confidence interval, 0%-1.5%). This has important implications for the management of exposures including the role of postexposure prophylaxis.

Refractory strictures post-esophageal atresia repair: what are the alternatives?

Esophageal strictures remain the most frequent complication after esophageal atresia (EA) repair despite refinements in operative techniques. With an incidence of anastomotic stricture between 8% and 49%, EA is the most frequent cause of benign esophageal stricture in children. The mainstay of treatment for esophageal stricture is dilatation with a 58-96% success rate. In order to relieve dysphagia, between 1 and 15 dilatations will be required in each EA patient with an esophageal stricture. However dilatations may lead to complications including perforation (0.1-0.4% of all esophageal benign strictures) and sociopsychological morbidity. Fifty percent of EA strictures will improve in 6 months. However, 30% will persist and require repeat dilatations. The present article explores the variety of non-surgical alternative treatments for anastomotic strictures after EA repair, focusing on triamcinolone acetonide, mitomycin C and esophageal stents. We propose an algorithm for a more standardized therapeutic approach, with the hope that an international panel of experts could meet and establish a consensus.

First Report of Ophiosphaerella herpotricha Causing Spring Dead Spot of Bermudagrass in Mississippi

Spring dead spot (SDS) is the most destructive disease of bermudagrass (Cynodon dactylon (L.) Pers.). Symptoms of SDS appear in the spring when bermudagrass transitions out of winter dormancy. These symptoms include depressed, straw-colored patches that range from several centimeters to a meter in diameter. Infected roots and rhizomes are black, brittle, and necrotic. The disease is caused by three species of fungi: Ophiosphaerella herpotricha (Fr:Fr) J. Walker; O. korrae (J. Walker & A.M. Smith) Shoemaker & C.E. Babcock; or O. narmari (J. Walker & A.M. Smith) Wetzel, Hubert & Tisserat. However, O. korrae is the most prevalent causal organism of SDS in the southeastern United States and was the only species reported in Mississippi (1). In April of 2006, root samples were collected from a bermudagrass putting green in Booneville, MS with a high level of SDS incidence and severity. Symptomatic roots were collected and surface disinfested in 0.6% NaOCl and plated on one-quarter-strength potato dextrose agar (PDA) amended with streptomycin sulfate and chloramphenicol. Hyphae growing from the roots were transferred to full-strength PDA after 5 to 7 days. Mycelium from five pure-culture colonies plus an O. herpotricha control was harvested after 4 weeks of growth and the genomic DNA was extracted. The genomic DNA of the Booneville isolates and the O. herpotricha control were amplified by PCR using species-specific primers OHITS1 and OHITS2 for O. herpotricha (2). Amplification of a 454-bp fragment of DNA confirmed one of the five unknown isolates as O. herpotricha. The other four isolates were not identified. 'Sahara' bermudagrass (4 weeks old in 3.8 × 20 cm Cone-tainers containing a sand and soil mixture) was inoculated with the Booneville-O. herpotricha isolate and the O. herpotricha control. One gram of oat seed infested with O. herpotricha isolates was inserted 2 cm below the crowns in the root zone of bermudagrass plugs. The inoculated bermudagrass plants were incubated for 4 weeks in the greenhouse. A control consisting of noninfested sterile oats was included. Following incubation, black, necrotic roots were observed on the plants inoculated with both O. herpotricha isolates. No symptoms were observed on roots of noninfested plants. Symptomatic roots were disinfested and plated on one-quarter-strength PDA. Koch's postulates were completed after O. herpotricha was reisolated from roots of plants inoculated with both O. herpotricha isolates and confirmed by PCR as mentioned above. The identification of O. herpotricha as a causal organism of SDS in Mississippi clarifies the involvement of multiple causal agents in this state and broadens the geographic distribution of this root-rot species. References: (1) F. B. Iriarte et al. Plant Dis. 88:1341, 2004. (2) N. A. Tisserat et al. Phytopathology 84:478, 1994.

Evaluation of transgenic cotton varieties and a glyphosate application on seedling disease incidence

A study was conducted to determine whether stand densities of transgenic cotton (Gossypium hirsutum) varieties, with or without glyphosate, were similar to conventional varieties of the same lineage group in Georgia and Mississippi. Transgenic and conventional cotton varieties were placed into five lineage groups of related varieties and seedling disease was evaluated in three greenhouse tests and a field trial using Rhizoctonia solani AG-4. Seed vigor was determined by standard germination studies were conducted evaluating conventional and transgenic varieties of similar lineage. Results showed that no interactions occurred for the heights and dry weight data across treatments within the lineage groups in any of the experiments. No interactions were shown between stand densities at different inoculum rates and inoculated versus uninoculated pots (plots). Across all greenhouse studies, stand counts of PM 1220 were similar to the transgenic varieties PM 1220 RR and PM 1220 B/RR with or without a glyphosate application. In the field trial, PM 1220 B/RR + glyphosate had significantly lower stands than all other treatments expect PM 1220 RR (no glyphosate treatment) prior to and after glyphosate application. Stand densities for varieties within the lineage group DPL 5415 were also inconsistent when compared between the greenhouse and field trials with no apparent trends occurring. However, the Coker 312 varieties containing glyphosate tolerance had consistently lower stand counts compared to the conventional variety of Coker 312 but only during the greenhouse studies. Seed germination of Coker 312 could not be correlated with either the greenhouse or field trial data. In general, the commercially available varieties such as PM 1220, DPL 5690, DPL 5415, and DPL 50 with glyphosate tolerance had similar stand count, height, and dry weight data when compared to the conventional varieties from the same lineage group regardless of a glyphosate application. When differences did occur, no consistent trends could be determined within these four lineage groups.

Management of Mason type-III radial head fractures with a titanium prosthesis, ligament repair, and early mobilization. Surgical technique

BACKGROUND

Radial head fractures often occur in association with other elbow fractures and soft-tissue injuries. Radial head replacement is indicated for irreparable radial head fractures associated with elbow instability. The purpose of this study was to analyze the results after treatment of such injuries with a titanium radial head prosthesis, repair of torn collateral ligaments, and early mobilization of the elbow.

MATERIALS

Sixteen patients with sixteen Mason type-III radial head fractures and collateral ligament injury were treated with use of a titanium radial head prosthesis over a five-year period at the Royal Adelaide Hospital and Modbury Public Hospital in South Australia. The surgery was performed acutely in ten patients and was delayed an average of thirty-seven days (range, fifteen to seventy-nine days) in six. All patients were followed clinically and radiographically for a mean of 2.8 years (range, 1.2 to 4.3 years).

RESULTS

Eight patients had an excellent result; five, a good result; and three, a fair result, according to the Mayo Elbow Performance Score. The three fair results occurred in patients with delayed surgery. The mean flexion contracture was 15 degrees (range, 0 degrees to 42 degrees ), with an average loss of 10 degrees (range, 0 degrees to 25 degrees ) of full flexion compared with that of the contralateral elbow. Both pronation and supination decreased an average of 12 degrees (range, 0 degrees to 45 degrees ) compared with that of the contralateral forearm.

CONCLUSIONS

The results of treatment of Mason type-III radial head fractures with a monoblock titanium radial head prosthesis and soft-tissue reconstruction are satisfactory. Early mobilization of the elbow is important for the restoration of elbow range of motion and function.

Evaluation of transgenic cotton varieties and a glyphosate application on seedling disease incidence

A study was conducted to determine whether stand densities of transgenic cotton (Gossypium hirsutum) varieties, with or without glyphosate, were similar to conventional varieties of the same lineage group in Georgia and Mississippi. Transgenic and conventional cotton varieties were placed into five lineage groups of related varieties and seedling disease was evaluated in three greenhouse tests and a field trial using Rhizoctonia solani AG-4. Seed vigor was determined by standard germination studies were conducted evaluating conventional and transgenic varieties of similar lineage. Results showed that no interactions occurred for the heights and dry weight data across treatments within the lineage groups in any of the experiments. No interactions were shown between stand densities at different inoculum rates and inoculated versus uninoculated pots (plots). Across all greenhouse studies, stand counts of PM 1220 were similar to the transgenic varieties PM 1220 RR and PM 1220 B/RR with or without a glyphosate application. In the field trial, PM 1220 B/RR + glyphosate had significantly lower stands than all other treatments expect PM 1220 RR (no glyphosate treatment) prior to and after glyphosate application. Stand densities for varieties within the lineage group DPL 5415 were also inconsistent when compared between the greenhouse and field trials with no apparent trends occurring. However, the Coker 312 varieties containing glyphosate tolerance had consistently lower stand counts compared to the conventional variety of Coker 312 but only during the greenhouse studies. Seed germination of Coker 312 could not be correlated with either the greenhouse or field trial data. In general, the commercially available varieties such as PM 1220, DPL 5690, DPL 5415, and DPL 50 with glyphosate tolerance had similar stand count, height, and dry weight data when compared to the conventional varieties from the same lineage group regardless of a glyphosate application. When differences did occur, no consistent trends could be determined within these four lineage groups.

Hybrid modeling and dynamic simulation of automated batch plants

A proposal is presented for the hybrid modeling and dynamic simulation of automated batch processing plants with dominant discrete-event behavior. The proposal encompasses current techniques for modeling continuous-time/discrete-event processes, synthesizing discrete-event controllers as well as the use of industrial standards for batch control. The result is a hierarchical-modular model of a plant in which process and control tasks are clearly differentiated. Implementation rules are established for a specific dynamic simulator capable of handling hybrid systems. The approach is demonstrated by building and verifying a complete model for an automated milk pasteurization plant. Results show that handling problems of realistic complexity is feasible using state-of-the-art technology.

PCR identification of dermatophyte fungi Trichophyton rubrum, T. soudanense and T. gourvilii

Diagnosis of dermatophytosis employing conventional laboratory procedures has been complicated by the slow growth and varied morphological features shown by dermatophytes. After analysis of the nucleotide base sequences of a 1.2-kb fragment amplified from a dermatophyte fungus Trichophyton rubrum by arbitrarily primed PCR with random primer OPD18, a pair of primers (TRIF and TR1R) was designed and evaluated for specific identification of T. rubrum. The sensitivity of the primers TR1F and TR1R was high, as a specific PCR band of c. 600 bp was detected from as little as 7 pg of T. rubrum DNA. By examining 92 dermatophyte strains and clinical isolates, it was found that this pair of primers reacted in PCR with T. rubrum, T. soudanense and T. gourvilii through formation of the specific fragment of 600 bp, but not with any other of the dermatophyte species or varieties, fungi, yeasts or bacteria tested. As T rubrum is one of the most frequently isolated dermatophyte fungi, and T. soudanense and T. gourvilii are relatively uncommon in many parts of the world, these primers can be used for rapid, sensitive and specific identification and differentiation of T. rubrum from other fungi and micro-organisms.

Organs/systems potentially involved in one model of programmed hypertension in sheep

1. When pregnant ewes and their fetuses are exposed to the synthetic glucocorticoid dexamethasone for 2 days early in pregnancy (days 26-28; term 145-150 days), female offspring have increased blood pressure relative to a control group. In one series, this was shown to be due to increased cardiac output, concomitant with a reset mean arterial pressure/heart rate reflex. The first group of such animals had, by the age of 7 years, left ventricular hypertrophy and reduced cardiac functional capacity. 2. The elevation in blood pressure is not maintained by any change in the peripheral renin-angiotensin system (RAS). 3. There is, however, preliminary evidence that some aspects of local RAS (particularly in the kidney and brain) could have participated in the 'programming' event. The levels of mRNA for angiotensin II receptors (AT1, AT2) and angiotensinogen are increased in the kidney of such dexamethasone-treated fetuses in late gestation (130 days), some 100 days after steroid treatment. Similar increases in AT1 mRNA in the medulla oblongata of the fetal brain and large increases of mRNA for angiotensinogen occur in the hypothalamus. 4. These findings, together with evidence from the literature, suggest that both the kidney and parts of the brain are affected by events that also 'program' high blood pressure in the offspring of animals in which the intra-uterine environment has been perturbed at some stage.

A specific PCR assay for the dermatophyte fungus Microsporum canis

A DNA fragment of approximately 1.2 kb, generated from the common dermatophyte Microsporum canis by arbitrarily primed polymerase chain reaction (PCR) using random primer OPU13, was cloned and sequenced. Based on the resulting sequencing data, a forward primer (MC1F) and a reverse primer (MC1R) have been designed and assessed by PCR for their usefulness in the improved identification of M. canis. The results obtained suggest that these primers are specific for M. canis, as a band of 900 bp was amplified in PCR with genomic DNA from M. canis only, and not from any of the other dermatophyte species or varieties, other fungi or common bacteria examined. Combining this PCR technique with a rapid mini-preparation method for fungal DNA, a definitive diagnosis of M. canis can be achieved within a day from the primary cultures. Future refinement of a DNA purification protocol from clinical specimens would further enhance the potential of the PCR based test for improved detection and identification of M. canis.

Functional glucocorticoid receptors in the mesonephros of the ovine fetus

BACKGROUND

At 27 days of gestation in the ovine fetus (term = 145 to 150 days), the only kidney is the mesonephros, and allantoic fluid represents fetal urine. The hypothesis tested in this study was that functional glucocorticoid receptors (GRs) are present in this early mesonephric kidney.

METHODS

Pregnant ewes, between 26 and 30 days, were infused with saline, dexamethasone (0.48 mg/hour), cortisol (5 mg/hour), or aldosterone (10 microg/hour) for 48 hours and were then killed for collection of fetuses and fetal fluids. GR mRNA was measured by real-time polymerase chain reaction in whole fetuses, and the location of gene expression was determined by hybridization histochemistry.

RESULTS

Significant changes in allantoic fluid composition were produced by the exposure of the fetus to maternally infused synthetic (dexamethasone) and natural (cortisol) glucocorticoids, over a period of two days, compared with fetuses of ewes infused with vehicle (isotonic saline; N = 8) or aldosterone (N = 8). Volume of fluid was unchanged by any treatment, but both dexamethasone (N = 10) and cortisol (N = 8) caused significant (P < 0.05) decreases in sodium and chloride concentrations and increases in concentrations of potassium, urea, glucose, and fructose. GR mRNA was detected in equivalent concentrations in the whole fetuses of saline, dexamethasone, and cortisol treatments. The GR mRNA levels were significantly decreased in the aldosterone group. By hybridization histochemistry, GR mRNA was detected in most of the tubular cells of the mesonephros.

CONCLUSION

These results suggest that functional GRs are present in the early ovine mesonephros.

First Report of Rhizoctonia solani AG-7 on Cotton in Mississippi

During a field study of the soilborne mycobiota on cotton (Gossypium hirsutum L.) roots, Rhizoctonia solani Kühn AG-7 was isolated from dark brown lesions present on the tap, feeder, and secondary roots onto potato-dextrose agar (PDA) (34 g of medium per liter of distilled water). Isolate identification was confirmed using tester R. solani AG-7 isolates (Carling, University of Alaska) for comparison during anastomosis pairing. To confirm pathogenicity, six AG-7 isolates (65, 66, 67, 68, 69, 70) obtained from cotton roots were tested in a plant growth incubator (18-24°C) by mixing 2.5 ml of 2-week-old cornmeal sand inoculum (3 g cornmeal, 100 g sand, and 20 ml distilled water) with 500 ml of autoclaved soil into each of five replicate polystyrene pots (15 cm wide × 20 cm long) per isolate. Five control pots containing noninfested soil were added for comparison. Five seed of cv. Deltapine 50 were sown into each pot. For all six isolates, mean stand counts (ranging from 0 and 1.3 plants per pot) were significantly lower (P ≤ 0.05) compared with those of plants in noninfested pots (3.8 plants per pot) at 21 days after planting. Furthermore, when the roots of surviving seedlings were evaluated for disease severity, brown, discolored lesions were observed at the base of stems and on roots in infested pots for all six isolates. Six AG-7 cultures of the pathogen were reisolated from symptomatic tissues onto PDA. The experiment was repeated with similar results. This is the first report of AG-7 occurring in Mississippi.

Application of PCR to the identification of dermatophyte fungi

Infection of the keratinised tissues (skin, hair and nails) in man and animals by keratinophilic fungi (dermatophytes) results in dermatophytosis (also known as tinea or ringworm). As conventional laboratory procedures for the identification of dermatophytes are either slow or lack specificity, improved diagnostic methods are required. The application of nucleic acid amplification technology has made rapid and precise identification of dermatophytes possible. Recent studies have shown that when one of the four random primers (OPAA11, OPD18, OPAA17 and OPU15) was used in arbitrarily primed PCR (AP-PCR), up to 20 of the 25 dermatophyte species or subspecies under investigation could be distinguished on the basis of characteristic band patterns detected in agarose gel electrophoresis. A combination of two random primers (OPD18 and OPAA17) used in separate reaction tubes identified 23 of the 25 dermatophyte species or subspecies examined. AP-PCR provides a rapid and practical tool for identification of dermatophyte isolates that is independent of morphological and biochemical characteristics and thus enhances laboratory diagnosis of dermatophytosis.

Ontogeny of aquaporins 1 and 3 in ovine placenta and fetal membranes

A sensitive and highly reproducible method has been used to show that Aquaporin 3 (AQP(3)) mRNA is present in the ovine placenta and chorion from at least 60 days of gestation (term=145-150d) with levels increasing substantially (>16 fold) at 100 days, and remaining constant thereafter. By immuno- and hybridization histochemistry, the epithelial cells expressing AQP(3)were found to be the trophoblast cells. Some AQP(3)was expressed in fibroblasts of the amnion and allantois but none was expressed in the epithelia of these membranes. AQP(1)was expressed in endothelial cells of fetal and maternal blood vessels but not in any epithelial cell of the ovine placenta and fetal membranes. The level of AQP(3)expression is consistent with known ovine placental permeabilities to water, glycerol and urea.