The impact of lung ultrasound assessment during a whole lung lavage: A paediatric case of pulmonary alveolar proteinosis

Whole lung lavage (WLL) is the first-line treatment for pulmonary alveolar proteinosis. We hypothesized that lung ultrasound (LUS) would guide flooding during treatment in a 15-year-old boy. WLL of each lung consisted of instillation of saline followed by kinesiotherapy and fluid drainage. In the first WLL, the lung was repeatedly flooded until the lavage fluid was clear on macroscopic examination. During this process, LUS was used to visualise lung aeration. In the second WLL, we used LUS signs to guide the lavage volume. The appearance of the fluid bronchogram sign showed that saline infusion could be stopped earlier than in the first lavage. In conclusion, LUS helped monitor the different stages of controlled lung de-aeration during WLL and reduce the total amount of saline used. This technique will also reduce the risk of WLL-related complications.

AB1586-PARE MULTI-CENTER, RANDOMIZED, OPEN-LABEL, 2-ARM PARALLEL STUDY TO COMPARE THE PHARMACOKINETICS, SAFETY AND TOLERABILITY OF AVT02 ADMINISTERED SUBCUTANEOUSLY VIA PREFILLED SYRINGE OR AUTOINJECTOR IN HEALTHY ADULT VOLUNTEERS

Background

AVT02 is an investigational biosimilar to adalimumab. It is approved in Europe, Canada, and the UK. It is not approved by the US Food and Drug Administration (FDA).

Objectives

To evaluate the pharmacokinetic similarity of 100 mg/mL AVT02, an investigational biosimilar of adalimumab, when administered either via a pre-filled syringe, or with a newly developed autoinjector in healthy adult subjects.

Methods

This was a Phase 1, randomized, open-label, parallel-group study in which 207 healthy adult subjects were randomized in a 1:1 ratio to receive 100 mg/mL AVT02 either via a pre-filled syringe, or with an autoinjector, stratified by body weight. Subjects received a single subcutaneous 40 mg dose on Day 1. Pharmacokinetics, immunogenicity, local injection site reactions, and adverse events were assessed prior to, and up to 64 days after, study drug administration.

Results

The results observed supported the assessment of pharmacokinetic similarity of investigational AVT02 administered by pre-filled syringe or with an autoinjector. The 90% CIs for the ratios of geometric least square means for the primary pharmacokinetic parameters Cmax, AUC0-t, and AUC0-∞ were contained within prespecified margins 80% and 125%, based on an analysis of variance model with treatment as a fixed effect. The mean serum concentration-time profile of adalimumab by treatment group is shown in Figure 1.

Figure 1.

Mean Serum Concentration-Time Profile of Adalimumab by Treatment Group on Semilogarithmic Scale (Pharmacokinetic Population)

Binding anti-drug antibodies were detectable at the end of study visit on Day 64 in 100% and 97.0% of subjects in the pre-filled syringe administration and the autoinjector groups, respectively. Of those subjects positive for anti-drug antibodies, 85.7% and 86.5% further tested positive for neutralizing antibodies in the pre-filled syringe administration and autoinjector groups, respectively. The frequency of local administration site reactions was 11.8% overall and similar between treatment groups. The most frequently reported treatment-emergent adverse events in both treatment groups were under the SOC: Infections and infestations (56.0% in the AVT02-pre-filled syringe group and 45.2% in the AVT02-autoinjector group). The safety profiles were generally similar between treatment groups.

Conclusion

The results observed supported the assessment of pharmacokinetic similarity between the pre-filled syringe and autoinjector delivery systems after a single subcutaneous 40 mg dose. The autoinjector delivery system was generally well tolerated in healthy subjects, with a safety and immunogenicity profile similar to that observed with 100 mg/mL AVT02 administered using a pre-filled syringe.

ClinicalTrials.gov Identifier: NCT03983876

Disclosure of Interests

Christopher Wynne: None declared, Heimo Stroissnig Employee of: Alvotech, Roshan Dias Employee of: Alvotech, Joanna Sobierska Employee of: Alvotech, Eric Guenzi Employee of: Alvotech, Hendrik Otto Employee of: Alvotech, Abid Sattar Employee of: Alvotech, Halimu N. Haliduola Employee of: Alvotech, Elin Edwald Employee of: Alvotech, Fausto Berti Employee of: Alvotech

PURA syndrome in a child with severe developmental delay: a challenging diagnosis

INTRODUCTION

PURA syndrome is a rare autosomal dominant condition caused by de novo pathogenic variants in PURA gene and characterized by a multisystemic phenotype that includes global neurodevelopmental delay, early hypotonia, absence of speech, feeding difficulties, hypersomnolence, epilepsy and movement disorders.

CASE REPORT

We report a 9-year-old girl with hypotonia and feeding difficulties with failure to thrive since the neonatal period. At the age of 3 years motor and intellectual delay were evident, she had a wide-based gait, no speech and an exaggerated acoustic startle response. She developed hand-mouthing stereotypies and epilepsy at 6 years old. The 24 hours continuous electroencephalogram monitoring revealed global slow activity and frequent epileptiform activity in left temporal and centrotemporal areas. The brain MRI revealed delayed myelination. At 6 years old the clinical exome sequencing identified a heterozygous pathogenic variant in the PURA gene, c.153delA p.(Leu54CysfsTer24).

CONCLUSION

PURA syndrome has clinical features similar to other neurological disorders but the association with some clinical features, not as common in other neurological entities, like never being able to speak but being able to follow simple orders and exaggerated acoustic startle response, should raise the suspicion of PURA syndrome and genetic analysis must be performed to confirm the diagnosis and provide early multidisciplinary intervention.

Postpartum headache after epidural anaesthesia: Who to blame?

INTRODUCTION

Epidural analgesia is considered the preferred analgesic choice during labour. Post dural puncture headache (PDPH) is considered a potential complication of this analgesic technique and is a frequently hypothesis for any headache occurring after delivery. It is essential that anaesthetists and obstetricians are familiar with other possible differential diagnosis for postpartum headache (PPH).

CASE DESCRIPTION

37-year-old female presented after delivery with intense occipital pulsatile headache associated with neck radiation, nausea and vomiting, hemodynamically stable and normal neurologic physical examination. Abnormalities in thyroid hormone levels were found. CT-scan findings suggested pituitary apoplexy.

DISCUSSION

There are many differential diagnoses for PPH and some are rarely considered, such as pituitary apoplexy. It is essential to differentiate signs and symptoms of each diagnosis, since many of them overlap.

CONCLUSION

Not all postpartum headaches are PDPH and the first suspected diagnosis may not always be accurate.

Postpartum headache after epidural anaesthesia: Who to blame?

INTRODUCTION

Epidural analgesia is considered the preferred analgesic choice during labour. Post dural puncture headache (PDPH) is considered a potential complication of this analgesic technique and is a frequently hypothesis for any headache occurring after delivery. It is essential that anaesthetists and obstetricians are familiar with other possible differential diagnosis for postpartum headache (PPH).

CASE DESCRIPTION

37-year-old female presented after delivery with intense occipital pulsatile headache associated with neck radiation, nausea and vomiting, hemodynamically stable and normal neurologic physical examination. Abnormalities in thyroid hormone levels were found. CT-scan findings suggested pituitary apoplexy.

DISCUSSION

There are many differential diagnoses for PPH and some are rarely considered, such as pituitary apoplexy. It is essential to differentiate signs and symptoms of each diagnosis, since many of them overlap.

CONCLUSION

Not all postpartum headaches are PDPH and the first suspected diagnosis may not always be accurate.

17α-Ethinylestradiol and 17β-estradiol removal from a secondary urban wastewater using an RBC treatment system

The presence of micropollutants that include endocrine-disrupting compounds (EDC) in aquatic environments is currently one of the most relevant aspects of water quality due to their adverse effects on aquatic organisms and human health. From the several categories of EDC, 17β-estradiol (E2) is a natural hormone, which is prevalent in vertebrates, associated with the female reproductive system and maintenance of the sexual characters. 17α-Ethinylestradiol (EE2) is a synthetic hormone produced from the natural hormone E2 and is an essential component of oral contraceptives. These compounds are susceptible to bioconcentration and have high potential to bioaccumulation. Wastewater treatment plants are the main point source of E2 and EE2 into aquatic environments, but conventional wastewater treatment systems are not specifically designed for steroid removal. To overcome this problem, biological tertiary treatment may be a solution for the removal of emergent pollutants such as E2 and EE2. The main purpose of the present study is to provide a solution based on the optimization of a rotating biological contactor system to remove estrogens, specifically E2 and EE2, and to quantify their removal efficiency on different matrices, namely real wastewater and different synthetic wastewaters. All assays presented viable removal efficiencies for compound E2 with values always above 50%; real wastewater yielded the highest removal efficiencies. EE2 removal had better removal efficiencies with synthetic wastewater as feed solution, with removals above 15%, whereas the removal efficiency with real wastewater was inexistent.

Acompanhamento eletrocardiográfico no desenvolvimento de ratos Wistar

RESUMO A atividade elétrica cardíaca pode ser registrada por meio do eletrocardiograma (ECG), registro capaz de captar as alterações do percurso elétrico. Na literatura científica, não existe descrição de padrões eletrocardiográficos de ratos Wistar desde a fase de recém-nascidos até serem considerados envelhecidos. O objetivo do presente estudo foi avaliar o padrão eletrocardiográfico de ratos Wistar desde a fase de recém-nascidos até serem considerados envelhecidos, no intuito de que os resultados possam contribuir como referencial dos padrões da espécie. Foram utilizados ratos Rattus novergicus albinus, da linhagem Wistar. Os ratos foram divididos em cinco grupos experimentais, sendo definidos de acordo com a idade e assim denominados: grupo 21 dias (21D), dois meses (2M), três meses (3M), sete meses (7M) e 18 meses (18M), sendo n=20 por grupo. Para a realização do ECG, eletrodos conectados aos canais do eletrocardiógrafo foram posicionados nos animais e captaram o sinal elétrico do coração em seis derivações. Os dados foram agrupados e submetidos a comparação por meio de ANOVA e teste de Tukey-Kramer, P≤0,05. Os resultados mostraram que, de forma geral, as modulações ao longo do processo de envelhecimento diante dos parâmetros relacionados ao ECG se iniciam a partir do período 2M, com aparente estabilidade até 3M e/ou 7M, seguindo por exacerbação das modulações em 7M e/ou 18M, a depender da variável eletrocardiográfica em questão. Em relação à frequência cardíaca (FC), concomitantemente, nota-se um padrão similar, ou seja, diminuição dela a partir do período 2M, com estabilidade até 7M, seguindo por diminuição mais pronunciada em 18M. Os resultados sugerem que, devido ao processo de envelhecimento, o coração de ratos Wistar apresenta modificações na condução do estímulo elétrico, bem como redução na FC, fatores que merecem atenção enquanto indicadores de inclusão/exclusão de animais em grupos experimentais por parte de pesquisadores que utilizam a referida espécie como modelo de estudo.

MPI-blastn and NCBI-TaxCollector: improving metagenomic analysis with high performance classification and wide taxonomic attachment

Metagenomic sequencing technologies are advancing rapidly and the size of output data from high-throughput genetic sequencing has increased substantially over the years. This brings us to a scenario where advanced computational optimizations are requested to perform a metagenomic analysis. In this paper, we describe a new parallel implementation of nucleotide BLAST (MPI-blastn) and a new tool for taxonomic attachment of Basic Local Alignment Search Tool (BLAST) results that supports the NCBI taxonomy (NCBI-TaxCollector). MPI-blastn obtained a high performance when compared to the mpiBLAST and ScalaBLAST. In our best case, MPI-blastn was able to run 408 times faster in 384 cores. Our evaluations demonstrated that NCBI-TaxCollector is able to perform taxonomic attachments 125 times faster and needs 120 times less RAM than the previous TaxCollector. Through our optimizations, a multiple sequence search that currently takes 37 hours can be performed in less than 6 min and a post processing with NCBI taxonomic data attachment, which takes 48 hours, now is able to run in 23 min.

Aspergillus flavus contamination in two Portuguese wastewater treatment plants

Filamentous fungi from genus Aspergillus were previously detected in wastewater treatment plants (WWTP) as being Aspergillus flavus (A. flavus), an important toxigenic fungus producing aflatoxins. This study aimed to determine occupational exposure adverse effects due to fungal contamination produced by A. flavus complex in two Portuguese WWTP using conventional and molecular methodologies. Air samples from two WWTP were collected at 1 m height through impaction method. Surface samples were collected by swabbing surfaces of the same indoor sites. After counting A. flavus and identification, detection of aflatoxin production was ensured through inoculation of seven inoculates in coconut-milk agar. Plates were examined under long-wave ultraviolet (UV; 365 nm) illumination to search for the presence of fluorescence in the growing colonies. To apply molecular methods, air samples were also collected using the impinger method. Samples were collected and collection liquid was subsequently used for DNA extraction. Molecular identification of A. flavus was achieved by real-time polymerase chain reaction (RT-PCR) using the Rotor-Gene 6000 qPCR detection system (Corbett). Among the Aspergillus genus, the species that were more abundant in air samples from both WWTP were Aspergillus versicolor (38%), Aspergillus candidus (29.1%), and Aspergillus sydowii (12.7%). However, the most commonly species found on surfaces were A. flavus (47.3%), Aspergillus fumigatus (34.4%), and Aspergillus sydowii (10.8%). Aspergillus flavus isolates that were inoculated in coconut agar medium were not identified as toxigenic strains and were not detected by RT-PCR in any of the analyzed samples from both plants. Data in this study indicate the need for monitoring fungal contamination in this setting. Although toxigenic strains were not detected from A. flavus complex, one cannot disregard the eventual presence and potential toxicity of aflatoxins.

Rare digital tumours: two case reports and mini review

Masses within the fingers and hands are a common occurrence affecting patients of all ages. Although most will be benign conditions, rarer more aggressive tumours also occur. Two cases of rare hand tumours, a digital myofibroma and an aggressive digital papillary adenocarcinoma are reported here including a mini-review of the literature. Although these two cases are quite different they highlight the importance of having a high index of suspicion for the presence of malignant change in masses that have been quiescent for considerable periods of time and thus the need for histological diagnosis in masses resected from the hands. The myofibroma, like other conditions such as giant cell tumours, although benign can have very worrying clinical features, most notably bony destruction. The aggressive digital papillary adenocarcinoma conversely can appear benign clinically but biologically is very aggressive with a high propensity for local and distant spread.

Cortical strut allografting in reconstructive orthopaedic surgery

Many approaches are used in the repair of skeletal defects in reconstructive orthopaedic surgery, and bone grafting is involved in virtually every procedure. Autografting remains the gold standard for replacing bone loss. However, the limited amount of bone that can be harvested and the morbidity associated with that procedure are major constraints to the clinical use of autografts. In contrast, bone allografts can be used in any kind of surgery, whether involving minor defects or major bone loss. Cortical strut allografts unite to host bone through callus formation, restoring bone stock and can be used as an onlay biological plate. These struts can be made from hemicylinders of tibia being fixed to host bone by circumferential metallic cables or by screws. The purpose of this study was to analyze the radiographic outcomes of twelve cryopreserved cortical onlay strut allografts, used in a group of nine patients, for revision hip arthroplasty of the femoral side, to stabilize femoral periprosthetic fractures, to reinforce poor cortical bone and to treat one atrophic femoral nonunion. The average follow-up period was 4.3 years (range, 1.6 to 9 years). No fractures, nonunions or progressive resorption of the bone allografts were observed. All struts were incorporated to the native femur with minimal resorption, within the first year after surgery. There was no failure of any of the allograft reconstructions.The results obtained show that cortical onlay strut allografts, either alone or in conjunction with metallic plate or cancellous bone allografts, are a valuable adjunct for reconstructive surgery of the hip and to treat atrophic femoral nonunion.

Menstrual irregularity: a possible clinical marker of metabolic dysfunction in women with class III obesity

PURPOSE

To evaluate whether menstrual irregularity in morbidly obese women is indicative of metabolic dysfunction.

PATIENTS AND METHODS

Fifty-seven women with morbid obesity were evaluated. They were divided into two groups: one comprising women without menstrual dysfunctions or hirsutism (Group 1), and another obese women showing menstrual dysfunction with or without hirsutism (Group 2). The following were evaluated: age, colour, childbirth, marital status, profession, socio-economic level, education, age at menarche, body weight, height, body mass index, presence of hirsutism (Ferriman Gallwey Index), abdominal circumference, hip circumference, waist-to-hip ratio, menstrual cycle, blood pressure, presence of acanthosis nigricans, insulin resistance (IR), fasting glycaemia, total cholesterol, HDL-C, LDL-C, triglycerides, thyroid-stimulating hormone, free T4, luteinising hormone (LH), follicle-stimulating hormone, prolactin, total testosterone, dehydroepiandrosterone sulfate, insulin and the Homeostasis Model Assessment (HOMA test).

RESULTS

Clinical and epidemiological aspects did not present statistical differences. Clinical and laboratory parameters did not show statistically significant alterations; however, HOMA test values for Group 2 were significantly higher than those for Group 1.

CONCLUSIONS

The presence of IR in class III obese women can cause menstrual dysfunctions such as amenorrhoea or oligomenorrhoea even in the absence of hyperandrogenism, suggesting that IR plays an important role in the ovarian mechanisms involved in the menstrual cycle control.

Trial-unique, delayed nonmatching-to-location (TUNL): a novel, highly hippocampus-dependent automated touchscreen test of location memory and pattern separation

The hippocampus is known to be important for learning and memory, and is implicated in many neurodegenerative diseases. Accordingly many animal models of learning and memory focus on hippocampus-dependent tests of location learning and memory. These tests often use dry mazes or water mazes; however automated testing in operant chambers confers many advantages over such methods. Some automated tests of location memory, such as delayed nonmatching-to-position (DNMTP) have, however, fallen out of favor following the discovery that such tasks can be solved using mediating behaviors that can bridge the delay and reduce the requirement for memory per se. Furthermore some researchers report that DNMTP performance may not always require the hippocampus. Thus, in an attempt to develop a highly hippocampus-dependent automated test of location memory that elicits fewer mediating behaviors, we have developed a trial-unique nonmatching-to-location (TUNL) task, carried out in a computer-automated touchscreen testing apparatus. To test the efficacy of this assay, rats with lesions to the hippocampus, or a sham lesion control group, were tested under a variety of conditions. Both groups were able to perform well at a delay of 1 s, but the lesion group was highly impaired when tested at a 6 s delay. Moreover, animals with lesions of the hippocampus showed a greater impairment when the distance between the locations was reduced. This result indicates that TUNL can be used to investigate both memory across a delay, and spatial pattern separation (the ability to disambiguate similar spatial locations). Performance-enhancing mediating behaviors during the task were found to be minimal. Thus, the TUNL task has the potential to serve as a powerful tool for the study of the neurobiology of learning and memory.

Establishing a minimum postmortem interval of human remains in an advanced state of skeletonization using the growth rate of bryophytes and plant roots

This paper illustrates the usefulness and efficiency of botanical evidence in establishing a minimum postmortem interval (PMI). The case under analysis refers to the remains of an adult male in an advanced state of skeletonization recovered from a wooded area in northern Portugal. The skeleton showed several taphonomical changes, which included the presence of green algae, bryophytes, and growing shrub roots in, around, and through the remains. By determining the age of both the bryophytes and shrub roots, it was concluded that the minimum amount of time elapsed since death was 3 years, to which several months or a few years have to be added to account for the complete decomposition of the remains. The disappearance of the presumptive individual had occurred 6 years before and is fully consistent with the estimate of the PMI. This report illustrates a novel use of bryophytes in a forensic setting.

Frequency of zoledronic acid (ZOL) administration to prevent aromatase inhibitor-associated bone loss (AIBL)

e11567

Background: Cancer patients (pts) are at increased risk of osteoporosis because of cancer treatment-induced bone loss. A hypogonadal state can increase bone resorption and turnover. Estrogen depletion with aromatase inhibitors (AIs), the preferred adjuvant treatment in postmenopausal women with early breast cancer (EBC), is associated with accelerated bone resorption and increased fracture risk. Several studies have demonstrated that IV ZOL can prevent AIBL in pts with EBC. ZOL to prevent AIBL was shown to be effective when administered every 6 mo in 4 large, randomized phase III trials. It is unknown if this is the optimal regimen. Methods: Pts who were receiving adjuvant breast cancer therapy with an AI and had a urinary N-telopeptide (uNTX) level > 50 nmol/mmol creatinine (Cr) and a bone density T-score < 1.5 at screening were treated with a single dose of ZOL 4 mg IV. Serum C-telopeptide (sCTX) and uNTX were obtained at baseline and then every 2 mo. Data are presently available from 10 pts who were followed for at least 6 mo and 1 pt followed for 2 mo after receiving ZOL. Wilcoxon signed-rank tests were performed for % change from baseline values. Results: Median baseline uNTX in these patients was 57.5 nmol/mmol Cr (range, 42.7 to 104.5). Median suppression of uNTX from baseline was 76.7% (range, 55.0% to 81.4%; P = .008) at 1 mo after therapy. At 6 mo, suppression of uNTX from baseline was 56.5% (range, 3.5% to 72.6%; P = .03). Similar significant suppression of sCTX up to 6 mo was observed. Continued suppression of uNTX and sCTX (approximately 50% decrease in median from baseline) was observed out to mo 12, although the number of pts studied is too small (n = 5 for uNTX and 4 for sCTX) to draw significant conclusions at this time. Pt accrual continues. Conclusions: A single dose of ZOL significantly suppressed bone resorption markers for at least 6 mo in pts receiving an adjuvant AI. It is not necessary to administer ZOL more frequently to prevent AIBL. These data suggest that ZOL administered every 6 mo is sufficient to prevent AIBL in this population. Further study will define whether this suppression of bone resorption markers continues for longer periods of time.

[Table: see text]

Lymphocyte and cytokines after short periods of exercise

The purpose of this study was to verify the effects of short periods of exercise of different intensity on lymphocyte function and cytokines. Thirty Wistar rats, 2 months old, were used. They were divided into five groups of six rats: a sedentary control group; a group exercised for 5 minutes at low intensity (5 L); a group exercised for 15 minutes at low intensity (15 L); and groups exercised at moderate intensity (additional load of 5 % of body weight) for 5 minutes (5 M) or for 15 minutes (15 M). The parameters measured were: total leukocytes, neutrophils, lymphocytes, monocytes, lymphocytes from lymph nodes, serum cytokines (IL-2, IL-6 and TNF-alpha), lymphocyte mitochondrial transmembrane potential, viability and DNA fragmentation. ANOVA two way followed by Tukey's post hoc test (p <or= 0.05) was used. The exercised groups exhibited a significant increase in total leukocytes, tissue and circulating lymphocytes in comparison with the control group. There was a significant decrease in lymphocyte viability and decrease in DNA fragmentation for the 15 M group when compared with the control. There was a decrease in the level TNF-alpha in the 5 M and 15 M groups. Short-term, low- and moderate-intensity exercise may be considered for sedentary individuals beginning to exercise, since no deleterious alterations were observed in lymphocyte function.

Hippocampal lesions in rats impair learning and memory for locations on a touch-sensitive computer screen: the "ASAT" task

It has been repeatedly demonstrated across species that the hippocampus is critical for spatial learning and memory. Consequently, numerous paradigms have been created to study spatial learning in the rodent. Most of these tasks, such as the Morris water maze, 8-arm radial maze, and T-maze, are non-automated procedures. It was our goal to create an automated task in the rodent that is quickly learned, hippocampal-dependent, and minimizes the confounding variables present in most tests measuring hippocampal-dependent learning and memory. To accomplish this, we created a novel search task using a standard operant box fitted with a touch-sensitive computer monitor. Subjects were required to locate an S+ "hidden" amongst other identical stimuli on the monitor. In two versions of the task the S+ stayed in the same location within a session but shifted location between sessions. In a third version of the task the S+ was moved to a new location after every 10 trials. It was found that the location of the S+ was quickly acquired each day (within 10 trials), and that the hippocampal-lesion group was impaired when compared to their control cohort. With the benefits inherent in automation, these tasks confer significant advantages over traditional tasks used to study spatial learning and memory in the rodent. When combined with previously developed non-spatial cognitive tests that can also be run in the touch-screen apparatus, the result is a powerful cognitive test battery for the rodent.

L-454,560, a potent and selective PDE4 inhibitor with in vivo efficacy in animal models of asthma and cognition

Type 4 phosphodiesterases (PDE4) inhibitors are emerging therapeutics in the treatment of a number of chronic disorders including asthma, chronic obstructive pulmonary disease (COPD) and cognitive disorders. This study delineates the preclinical profile of L-454,560, which is a potent, competitive and preferential inhibitor of PDE4A, 4B, and 4D with IC50 values of 1.6, 0.5 and 1.2 nM, respectively. In contrast to the exclusive binding of cilomilast and the preferential binding of roflumilast to the PDE4 holoenzyme state (Mg2+-bound form), L-454,560 binds to both the apo-(Mg2+-free) and holoenzyme states of PDE4. The intrinsic enzyme potency for PDE4 inhibition by L-454,560 also results in an effective blockade of LPS-induced TNFalpha formation in whole blood (IC50 = 161 nM) and is comparable to the human whole blood potency of roflumilast. The cytokine profile of inhibition of L-454,560 is mainly a Th1 profile with significant inhibition of IFNgamma and no detectable inhibition of IL-13 formation up to 1 microM. L-454,560 was also found to be efficacious in two models of airway hyper-reactivity, the ovalbumin (OVA) sensitized and challenged guinea pig and the ascaris sensitized sheep model. Furthermore, L-454560 was also effective in improving performance in the delayed matching to position (DMTP) version of the Morris watermaze, at a dose removed from that associated with potential emesis. Therefore, L-454,560 is a novel PDE4 inhibitor with an overall in vivo efficacy profile at least comparable to roflumilast and clearly superior to cilomilast.

The discriminatory value of the low-dose dexamethasone suppression test in the investigation of paediatric Cushing's syndrome

BACKGROUND

Low- and high-dose dexamethasone suppression tests (LDDST, HDDST) are used in the investigation of Cushing's syndrome (CS). In adults with Cushing's disease (CD), cortisol suppression during LDDST predicts suppression during the HDDST.

METHODS

We reviewed the results of the LDDST (0.5 mg 6 hourly x 48 h), HDDST (2.0 mg 6 hourly x 48 h) and corticotrophin-releasing hormone (CRH) test in 32 paediatric patients with CS: 24 had CD, 1 ectopic ACTH syndrome, 5 nodular adrenal hyperplasia and 2 adrenocortical tumours.

RESULTS

In CD, LDDST suppressed cortisol from 590.7 +/- 168.8 (mean +/- SD) to 333.7 +/- 104.0 nmol/l after 48 h (0 vs. 48 h, p < 0.05; mean suppression, 45.1%; CI (30.8, 59.4%); 16/24 (66%) suppressed >30%; mean suppression 68.1%, CI (58.1, 77.9%)). The HDDST suppressed cortisol from 596.3 +/- 174.5 to 47.1 +/- 94.8 nmol/l after 48 h (0 vs. 48 h, p < 0.05; mean suppression, 93.5%; CI (88.2, 98.8%) with 17/24 (71%) suppressing to <50 nmol/l and 100% to <50% of baseline). In the LDDST, suppression correlated with that during the HDDST (r = +0.45, p < 0.05) with >30% suppression predicting that in the HDDST and hence CD. CRH increased cortisol by +100.3% (CI 62, 138.5%), 22/24 (91.7%) showing a >20% increase. In the other CS pathologies (n = 8) the LDDST induced no significant decrease in cortisol.

CONCLUSION

The LDDST was of diagnostic value by discriminating between CD and other CS aetiologies. In our view the HDDST is redundant in the investigation of paediatric CS.