IL11-mediated stromal cell activation may not be the master regulator of pro-fibrotic signaling downstream of TGFβ

Fibrotic diseases, such as idiopathic pulmonary fibrosis (IPF) and systemic scleroderma (SSc), are commonly associated with high morbidity and mortality, thereby representing a significant unmet medical need. Interleukin 11 (IL11)-mediated cell activation has been identified as a central mechanism for promoting fibrosis downstream of TGFβ. IL11 signaling has recently been reported to promote fibroblast-to-myofibroblast transition, thus leading to various pro-fibrotic phenotypic changes. We confirmed increased mRNA expression of IL11 and IL11Rα in fibrotic diseases by OMICs approaches and in situ hybridization. However, the vital role of IL11 as a driver for fibrosis was not recapitulated. While induction of IL11 secretion was observed downstream of TGFβ signaling in human lung fibroblasts and epithelial cells, the cellular responses induced by IL11 was quantitatively and qualitatively inferior to that of TGFβ at the transcriptional and translational levels. IL11 blocking antibodies inhibited IL11Rα-proximal STAT3 activation but failed to block TGFβ-induced profibrotic signals. In summary, our results challenge the concept of IL11 blockade as a strategy for providing transformative treatment for fibrosis.

A novel, safe, fast and efficient treatment for Her2-positive and negative bladder cancer utilizing an EGF-anthrax toxin chimera

Bladder cancer is the sixth most common cancer in the United States, and it exhibits an alarming 70% recurrence rate. Thus, the development of more efficient antibladder cancer approaches is a high priority. Accordingly, this work provides the basis for a transformative anticancer strategy that takes advantage of the unique characteristics of the bladder. Unlike mucin-shielded normal bladder cells, cancer cells are exposed to the bladder lumen and overexpress EGFR. Therefore, we used an EGF-conjugated anthrax toxin that after targeting EGFR was internalized and triggered apoptosis in exposed bladder cancer cells. This unique agent presented advantages over other EGF-based technologies and other toxin-derivatives. In contrast to known agents, this EGF-toxin conjugate promoted its own uptake via receptor microclustering even in the presence of Her2 and induced cell death with a LC₅₀ < 1 nM. Furthermore, our data showed that exposures as short as ≈3 min were enough to commit human (T24), mouse (MB49) and canine (primary) bladder cancer cells to apoptosis. Exposure of tumor-free mice and dogs with the agent resulted in no toxicity. In addition, the EGF-toxin was able to eliminate cells from human patient tumor samples. Importantly, the administration of EGF-toxin to dogs with spontaneous bladder cancer, who had failed or were not eligible for other therapies, resulted in ~30% average tumor reduction after one treatment cycle. Because of its in vitro and in vivo high efficiency, fast action (reducing treatment time from hours to minutes) and safety, we propose that this EGF-anthrax toxin conjugate provides the basis for new, transformative approaches against bladder cancer.

Small molecules demonstrate the role of dynamin as a bi-directional regulator of the exocytosis fusion pore and vesicle release

Hormones and neurotransmitters are stored in specialised vesicles and released from excitable cells through exocytosis. During vesicle fusion with the plasma membrane, a transient fusion pore is created that enables transmitter release. The protein dynamin is known to regulate fusion pore expansion (FPE). The mechanism is unknown, but requires its oligomerisation-stimulated GTPase activity. We used a palette of small molecule dynamin modulators to reveal bi-directional regulation of FPE by dynamin and vesicle release in chromaffin cells. The dynamin inhibitors Dynole 34-2 and Dyngo 4a and the dynamin activator Ryngo 1-23 reduced or increased catecholamine released from single vesicles, respectively. Total internal reflection fluorescence (TIRF) microscopy demonstrated that dynamin stimulation with Ryngo 1-23 reduced the number of neuropeptide Y (NPY) kiss-and-run events, but not full fusion events, and slowed full fusion release kinetics. Amperometric stand-alone foot signals, representing transient kiss-and-run events, were less frequent but were of longer duration, similarly to full amperometric spikes and pre-spike foot signals. These effects are not due to alterations in vesicle size. Ryngo 1-23 action was blocked by inhibitors of actin polymerisation or myosin II. Therefore, we demonstrate using a novel pharmacological approach that dynamin not only controls FPE during exocytosis, but is a bi-directional modulator of the fusion pore that increases or decreases the amount released from a vesicle during exocytosis if it is activated or inhibited, respectively. As such, dynamin has the ability to exquisitely fine-tune transmitter release.

Damaging legacy: maternal cigarette smoking has long-term consequences for male offspring fertility

STUDY QUESTION

What are the effects on fertility of cigarette smoke-induced toxicity on male offspring exposed during the gestational/weaning period?

SUMMARY ANSWER

Maternal cigarette smoke exposure during the gestational/weaning period causes long-term defects in male offspring fertility.

WHAT IS KNOWN ALREADY

Cigarette smoke is a well-known reproductive toxicant which is particularly harmful to both fetal and neonatal germ cells. However, recent studies suggest a significant portion of young mothers in the developed world still smoke during pregnancy. In the context of male reproductive health, our understanding of the effects of in utero exposure on offspring fertility is limited.

STUDY DESIGN, SIZE, DURATION

In this study, 27 C57BL/6 5-week-old female mice were exposed via the nose-only to cigarette smoke (treatment) or 27 were exposed to room air (control) for 6 weeks before being housed with stud males to produce litters. In the treatment group, smoke exposure continued throughout mating, pregnancy and lactation until weaning of pups at 21 days post birth. Male offspring were examined at post-natal days 3, 6, 12, 21 and 98 (adult).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Approximately 108 maternal smoke-exposed C57BL/6 offspring and controls were examined. Spermatogenesis was examined using testicular histology and apoptosis/DNA damage was assessed using caspase immunohistochemistry and TUNEL. Sertoli cell morphology and fluctuations in the spermatogonial stem cell population were also examined using immunohistochemistry. Microarray and QPCR analysis were performed on adult testes to examine specific long-term transcriptomic alteration as a consequence of maternal smoke exposure. Sperm counts and motility, zona/oolemma binding assays, COMET analysis and mitochondrial genomic sequencing were also performed on spermatozoa obtained from adult treated and control mice. Fertility trials using exposed adult male offspring were also performed.

MAIN RESULTS AND THE ROLE OF CHANCE

Maternal cigarette smoke exposure caused increased gonocyte and meiotic spermatocyte apoptosis (P < 0.01) as well as germ cell depletion in the seminiferous tubules of neonatal and juvenile offspring. Aberrant testicular development characterized by abnormal Sertoli and germ cell organization, a depleted spermatogonial stem cell population (P < 0.01), atrophic seminiferous tubules and increased germ cell DNA damage (P < 0.01) persisted in adult offspring 11 weeks after exposure. Microarray analysis of adult offspring testes associated these defects with meiotic germ cell development, sex hormone metabolism, oxidative stress and Sertoli cell signalling. Next generation sequencing also revealed a high mitochondrial DNA mutational load in the testes of adult offspring (P < 0.01). Adult maternal smoke-exposed offspring also had reduced sperm counts with spermatozoa exhibiting morphological abnormalities (P < 0.01), affecting motility and fertilization potential. Odf2, a spermatozoa flagellum component required for coordinated ciliary beating, was also significantly down-regulated (P < 0.01) in maternal smoke-exposed adult offspring, with aberrant localization along the spermatozoa flagellum. Adult maternal smoke-exposed offspring took significantly longer to impregnate control females and had a slight but significant (P < 0.01) reduction in litter size.

LIMITATIONS, REASONS FOR CAUTION

This study examined only one species (mouse) using a smoking model which only simulates human cigarette smoke exposure.

WIDER IMPLICATIONS OF THE FINDINGS

This study represents the first comprehensive animal model of maternal smoking on male offspring reproductive function, suggesting that exposure during the gestational/weaning period causes long-term defects in male offspring fertility. This is due to a compromised spermatogonial stem cell population resulting from gonocyte apoptosis and impaired spermatogenic development. This results in significant germ cell damage and Sertoli cell dysfunction, impacting germ cell number, tubule organization, DNA damage and spermatozoa in adult offspring. This study strengthens the current literature suggesting that maternal exposure impairs male offspring fertility, which is currently debated due to conflicting studies.

STUDY FUNDING/COMPETING INTERESTS

This study was funded by the Australian Research Council, Hunter Medical Research Institute, National Health and Medical Research Council of Australia and the Newcastle Permanent Building Society Charitable Trust. The authors declare no conflict of interest.

Scrambled and fried: cigarette smoke exposure causes antral follicle destruction and oocyte dysfunction through oxidative stress

Cigarette smoke is a reproductive hazard associated with pre-mature reproductive senescence and reduced clinical pregnancy rates in female smokers. Despite an increased awareness of the adverse effects of cigarette smoke exposure on systemic health, many women remain unaware of the adverse effects of cigarette smoke on female fertility. This issue is compounded by our limited understanding of the molecular mechanisms behind cigarette smoke induced infertility. In this study we used a direct nasal exposure mouse model of cigarette smoke-induced chronic obstructive pulmonary disease to characterise mechanisms of cigarette-smoke induced ovotoxicity. Cigarette smoke exposure caused increased levels of primordial follicle depletion, antral follicle oocyte apoptosis and oxidative stress in exposed ovaries, resulting in fewer follicles available for ovulation. Evidence of oxidative stress also persisted in ovulated oocytes which escaped destruction, with increased levels of mitochondrial ROS and lipid peroxidation resulting in reduced fertilisation potential. Microarray analysis of ovarian tissue correlated these insults with a complex mechanism of ovotoxicity involving genes associated with detoxification, inflammation, follicular activation, immune cell mediated apoptosis and membrane organisation. In particular, the phase I detoxifying enzyme cyp2e1 was found to be significantly up-regulated in developing oocytes; an enzyme known to cause molecular bioactivation resulting in oxidative stress. Our results provide a preliminary model of cigarette smoke induced sub-fertility through cyp2e1 bioactivation and oxidative stress, resulting in developing follicle depletion and oocyte dysfunction.

Corticotropin releasing hormone--a GPCR drug target

Corticotrophin Releasing Hormone (CRH) is a primary hormone in the fight or flight response targeting a membrane bound G-protein coupled receptor (GPCR). Many people worldwide stand to benefit by the development of CRH agonists and antagonists for the treatment of anxiety and depression, with additional therapeutic targets including Alzheimer's, pain and the prevention of premature birth: so why the delay in development? In this review, we will discuss not only CRH, related proteins, receptors and ligands, but some of the obstacles that have arisen, as well as strategies being pursued to overcome these problems in the pursuit of this GPCR targeted therapeutic. Several key proteins influence the complex and intrinsic regulation of CRH, including its receptors (CRHR), of which 3 types have been categorised, CRHR(1), CRHR(2), CRHR(3), each containing active and inactive splice variants. Additionally, the CRH binding protein (CRHBP) is believed to moderate the effects of CRH at the receptor, whether it is as a molecular mop, or a delivery vessel, or both, is still being investigated. Homology based receptor modelling is a technique that has only recently become available with the crystallisation of bovine rhodopsin (a GPCR), [1] and the application of this technique to the CRH receptors is still in the early stages of development. Therefore, the medicinal chemist has previously had to rely on ligand-based strategies, specifically, the development of pharmacophores. Thus, an extensive number of both CRH peptide analogues and small ligands that show nanomolar antagonism have been developed with SAR libraries being integral to the iterative drug design process.

Small Molecule Inhibitors of Protein Kinases in Cancer- How to Overcome Resistance

Small molecule protein kinase inhibitors show great promise as anti-cancer agents, however, de novo and acquired resistance present problems. These are reviewed and illustrated using the receptor tyrosine kinase, KIT, as an example. Emerging solutions are presented, such as targeting active kinase conformations.

Comparison of Propofol-Lipuro with propofol mixed with lidocaine 10 mg on propofol injection pain

A common drawback of propofol is pain on injection and lidocaine is commonly mixed with propofol to reduce its incidence and severity. We conducted a randomised, prospective, double-blind study to compare injection pain following the administration of two different formulations of propofol in 200 unpremedicated ASA I-III adult patients scheduled for elective surgery under general anaesthesia. Patients were allocated randomly into two groups to receive either Propofol-Lipuro without added lidocaine or Diprivan mixed with lidocaine 10 mg. Five ml of the study solution was injected at a constant rate over 15 s and patients graded any associated pain or discomfort using a four-point verbal rating scale. The incidence of propofol injection pain was virtually identical in both study groups with 37/98 (38%) patients experiencing pain or discomfort following Propofol-Lipuro compared with 35/98 (36%) after Diprivan (p = 0.88). We observed no significant difference in pain scores between the groups (p = 0.67). Moderate or severe injection pain was experienced by 12/98 (12%) patients given Propofol-Lipuro compared with 8/98 (8%) given Diprivan (p = 0.48).

In search of evidence for occupational therapy: A new tool

Where is the evidence that occupational therapy intervention can make a difference? In short, it may be found somewhere among thousands of articles, spread over hundreds of journals. It is not surprising that surveys show that a major difficulty facing occupational therapists implementing evidence-based practice is the limited time they have to locate relevant research (Humphris et al, 2000; Bennett et al, 2003).

The efficacy of 5% lidocaine-prilocaine (EMLA) cream on pain during intravenous injection of propofol

Topical anesthesia using 60% lidocaine tape reduces the incidence of propofol injection pain. We conducted a randomized prospective double-blinded placebo-controlled study to assess the analgesic efficacy of pretreatment with topical 5% lidocaine-prilocaine (EMLA) cream in 90 ASA physical status I and II adult patients scheduled to undergo day-case gynecological surgery. Propofol injection pain was not reduced by pretreatment with EMLA cream, whereas the addition of lidocaine to propofol did significantly reduce propofol injection pain compared with the control group (P = 0.002). We conclude that topical anesthesia with EMLA cream applied for 60 min does not significantly reduce propofol injection pain.

The prevention of preterm labour -- corticotropin releasing hormone type 1 receptors as a target for drug design and development

The role of the corticotropin releasing hormone in the onset of labour and the subsequent medicinal chemistry implications of CRH antagonists for the prevention of premature birth, and identification of the CRH type 1 receptor as the target for this drug design, are reviewed here.

Effect of rescuer fatigue on performance of continuous external chest compressions over 3 min

Guidelines for the performance of cardiopulmonary resuscitation (CPR) have been revised recently and now advocate that chest compressions are performed without interruption for 3 min in patients during asystole and pulseless electrical activity. The aim of the present study was to determine if rescuer fatigue occurs during 3 min of chest compressions and if so, the effects on the rate and quality of compressions. Forty subjects competent in basic life support (BLS) were studied. They performed continuous chest compressions on a Laerdal Skillmeter Resusci-Anne manikin for two consecutive periods of 3 min separated by 30 s. The total number of compressions attempted was well maintained at approximately 100 min(-1) throughout the period of study. However, the number of satisfactory chest compressions performed decreased progressively during resuscitation (P < 0.001) as follows: first min, 82 min(-1); second, 68 min(-1); third, 52 min(-1); fourth, 70 min(-1); fifth, 44 min(-1); sixth, 27 min(-1). We observed significant correlations between the number of satisfactory compressions performed and both height and weight of the rescuer. Female subjects achieved significantly fewer satisfactory compressions compared with males (P = 0.03). Seven subjects (five female, two male) were unable to complete the second 3-min period because of exhaustion. We conclude that rescuer fatigue adversely affects the quality of chest compressions when performed without interruption over a 3-min period and that this effect may be greater in females due to their smaller stature. Consideration should be given to rotating the rescuer performing chest compressions after 1 min intervals.

The inhibition of protein phosphatases 1 and 2A: a new target for rational anti-cancer drug design?

Recent investigations in our laboratories have highlighted that the inhibition of the serine/threonine protein phosphatases 1 and 2A (PP1 and PP2A) is an excellent target for the development of novel anti-cancer agents. Using a combination of the known crystal structure of PP1 and the modelled structure of PP2A, we have rationally designed a new class of protein phosphatase inhibitors, cantharimides, which exhibit broad-spectrum anti-cancer activity. Synthetic modifications of the simplest known PP1 and PP2A inhibitor, norcantharidin, has led to the development of potent PP1 and PP2A inhibitors.

Cantharimides: a new class of modified cantharidin analogues inhibiting protein phosphatases 1 and 2A

Cantharidin and its analogues have been of considerable interest as potent inhibitors of the serine/threonine protein phosphatases 1 and 2A (PP1 and PP2A). However, limited modifications to the parent compounds is tolerated. As part of an on-going study we have developed a new series of cantharidin analogues, the cantharimides. Inhibition studies indicate that cantharimides possessing a D- or L-histidine, are more potent inhibitors of PP1 and PP2A (PP1 IC(50)=3.22+/-0.7 microM; PP2A IC(50)=0.81+/-0.1 microM and PP1 IC(50)=2.82+/-0.6 microM; PP2A IC(50)=1.35+/-0.3 microM, respectively) than norcantharidin (PP1 IC(50)=5.31+/-0.76 microM; PP2A IC(50)=2.9+/-1.04 microM) and essentially equipotent with cantharidin (PP1 IC(50)=3.6+/-0.42 microM; PP2A IC(50)=0.36+/-0.08 microM). Cantharimides with non-polar or acidic amino acid residues are only poor inhibitors of PP1 and PP2A.

A highly atom efficient, solvent promoted addition of tetraallylic, tetraallenic, and tetrapropargylic stannanes to carbonyl compounds

Tetraallylic, tetraallenic, and tetrapropargylic stannanes (0.25 equiv) react with aldehydes in methanol to provide unsaturated alcohols in good to excellent yields (56-99%). These reactions proceed exclusively with allylic rearrangement for tetra(2-butenyl)tin 2b and tetra(1,2-butadienyl)tin 16c and predominantly with allylic rearrangement for tetrapropadienyltin 16a and tetra(2-butynyl)tin 6e. Allylation reactions also proceeded smoothly with reactive ketones such as ethyl pyruvate (9a) and cyclohexanone (9b). The corresponding TFA-catalyzed reactions of dimethyl acetals 4d and 4e are regiospecific with allylic rearrangement.

Evaluation of the Pneupac Ventipac portable ventilator in critically ill patients

We assessed adequacy of ventilation in 20 critically ill patients with multiple organ failure using a Pneupac Ventipac portable ventilator and the effects on patients' haemodynamic stability. Baseline data were recorded over 15 min for a range of respiratory, haemodynamic and oxygen transport variables during ventilation with a standard intensive care ventilator (Engström Erica). Patients were then ventilated for 40 min using the portable ventilator. Finally, they were ventilated for a further 40 min using the standard intensive care ventilator. Heart rate, arterial and pulmonary artery pressures were recorded at 5-min intervals throughout the study period. Cardiac index and other haemodynamic data derived from a pulmonary artery catheter were recorded at 20-min intervals. Blood gas analysis was performed and oxygen transport data (oxygen delivery, oxygen consumption and physiological shunt) were calculated at the end of each of the three periods of ventilation. In general, no significant adverse effects of ventilation using the portable ventilator were observed for any of the variables studied. Arterial PO(2) increased significantly during ventilation with the portable ventilator, reflecting the use of a higher inspired oxygen fraction during this part of the study. Oxygen consumption decreased significantly in one patient during ventilation by the portable ventilator although none of the other variables measured in this patient was altered. We conclude that ventilation of critically ill patients using the Pneupac Ventipac portable ventilator was safe, satisfactory and associated with minimal adverse effects on respiratory, haemodynamic and oxygen transport variables.

Oral midazolam premedication for day case breast surgery, a randomised prospective double-blind placebo-controlled study

We conducted a randomised prospective double-blind placebo-controlled study to assess the efficacy of oral midazolam premedication in 50 ASA I and II female patients scheduled to undergo day case breast surgery. Anxiety was assessed using 100-mm visual analogue scales (VAS) and The State-Trait Anxiety Inventory (STAI) psychometric questionnaire. Midazolam premedication did not significantly reduce either VAS or STAI score, although heart rate and systolic arterial pressure immediately before induction of anaesthesia were significantly lower in patients who received midazolam (p = 0.006 and 0.039, respectively). Induction of anaesthesia was achieved with a lower dose of propofol (p = 0.0009) and excellent (Grade I) conditions for insertion of a laryngeal mask airway were achieved more often after midazolam premedication (p = 0.038). Arterial desaturation during induction of anaesthesia and insertion of a laryngeal mask airway occurred more often in patients who received placebo (p = 0.022). There was a good correlation between VAS and STAI used to assess the anxiolytic effects of premedication. (Spearman coefficient 0.58, p < 0.0001).

Small molecule inhibitors of serine/threonine protein phosphatases

Serine/threonine protein phosphatases have long been ignored as potential therapeutic targets for two reasons, one the biochemical significance of these proteins has not been appreciated and two, many natural protein phosphatase inhibitors are potent toxins and are considered unsuitable for clinical use. This review outlines the biochemical role of this protein family in cancer, cystic fibrosis, immunosuppression and, cardiac and neurological disorders. Particular emphasis is also given to the synthesis of selective small molecule inhibitors and their clinical exploitation.

A gene therapy/targeted radiotherapy strategy for radiation cell kill by

BACKGROUND

Although [131I]meta-iodobenzylguanidine (MIBG) is currently one of the best agents available for targeted radiotherapy, its use is confined to a few neural crest derived tumours which accumulate the radiopharmaceutical via the noradrenaline transporter (NAT). To determine whether this drug could be used for the treatment of non-NAT expressing tumours following genetic manipulation, we previously showed that plasmid mediated transfection of NAT into a non-NAT expressing glioblastoma cell line, UVW, endowed the host cells with the capacity to actively accumulate [131I]MIBG. We now present data defining the conditions required for complete sterilisation of NAT transfected cells cultured as multicellular spheroids and treated with [131I]MIBG.

METHODS

NAT transfected UVW cells, grown as monolayers and spheroids, were treated with various doses of [131I]MIBG and assessed for cell kill by clonogenic survival and measurement of spheroid volume over time (growth delay). Spheroids were left intact for different time periods to assess the effect of radiation crossfire on cell death.

RESULTS AND CONCLUSIONS

Total clonogen sterilisation was observed when the cells were grown as three-dimensional spheroids and treated with 7 MBq/ml [131I]MIBG. The added benefit of radiation crossfire was demonstrated by the improvement in cell kill achieved by prolongation of the maintenance of [131I]MIBG treated spheroids in their three-dimensional form, before disaggregation and clonogenic assay. When left intact for 48 h after treatment, spheroid cure was achieved by exposure to 6 MBq/ml [131I]MIBG. These results demonstrate that the efficiency of cell kill by [131I]MIBG targeted therapy is strongly dependent on beta-particle crossfire irradiation. This gene therapy/targeted radiotherapy strategy has potential for [131I]MIBG mediated cell kill in tumours other than those derived from the neural crest.

Auto-inhibition of Ca(2+)/calmodulin-dependent protein kinase II by its ATP-binding domain

Ca(2+)/calmodulin dependent protein kinase (CaMPK) II is a key enzyme in many physiological processes. The enzyme is inactive unless Ca(2+)/CaM binds to it. In this inactive form CaMPK-II does not bind ATP suggesting that the ATP-binding domain is involved in an intramolecular interaction. We show here that F12, a 12 amino acid long peptide fragment of the ATP-binding domain (CaMPK-II(23-34), GAFSVVRRCVKV) can inhibit the Ca(2+)/CaM-dependent activity (IC(50) of 3 microM) but has no effect on the Ca(2+)/CaM-independent activity of CaMPK-II. Kinetic analysis exhibited mixed inhibition with respect to autocamtide-2 and ATP. The inhibition by F12 showed specificity towards CaMPK-II, but also inhibited CaMPK-I (IC(50) = 12.5 microM), while CaMPK-IV (IC(50) = 85 microM) was inhibited poorly and cAMP-dependent protein kinase (PKA) was not inhibited. Substitution of phenylalanine at position 25 to alanine (A12), had little effect on the inhibition of different Ca(2+)/CaM-dependent protein kinases, suggesting that phenylalanine 25 does not play a crucial role in the interactions involving F12. Thus the molecular interactions involving the ATP-binding domain appears to play a role in the regulation of nonphosphorylated CaMPK-II activity.

Service utilization following traumatic brain injury

OBJECTIVES

To document service utilization by people with a traumatic brain injury at different times postinjury and to identify factors that predict service use.

DESIGN

Cross-sectional study design. Four groups of subjects were randomly selected from a regional database, according to their time postinjury: 6-18 months; 2-4 years; 6-9 years; and 10-17 years.

SUBJECTS

A total of 119 adults with a traumatic brain injury (TBI).

SETTING

Hospital and community-based clients in Sydney, Australia.

OUTCOME MEASURES

Glasgow Outcome Scale, Disability Rating Scale; Functional Independence Measure; Lidcombe Psychosocial Disability Scale; number, type, and frequency of services used in the previous 12 months.

RESULTS

Subjects in all four groups used a variety of services. The mean number of services used was 4.2, and there was only a moderate decline in service use over time. The use of medical and allied health services remained high in all four groups. Severity of injury, physical and cognitive disability, and psychosocial disability were all predictors of service utilization. Psychosocial disability was strongly associated with ongoing service utilization.

CONCLUSION

In this study, people with TBI used services well beyond the early stage of recovery. Psychosocial disability may be a better predictor of service use than physical and cognitive disability alone.

A gene therapy approach to enhance the targeted radiotherapy of neuroblastoma

BACKGROUND

The aims of this study were to determine whether the introduction and expression of the noradrenaline transporter (NAT) gene into NAT-negative neuroblastoma cell lines would make them amenable to targeted radiotherapy using [(131)I]MIBG.

PROCEDURE

Neuroblastoma cell lines were transfected with a eukaryotic expression vector containing the bovine noradrenaline transporter cDNA under the expression of the CMV promoter. Stable transfectants were created by selection in geneticin (G418) and were characterised for their MIBG uptake ability and susceptibility to [(131)I]MIBG therapy.

RESULTS

The cell line SK-N-MC, which normally shows no ability to take up MIBG, was successfully transfected with bNAT. SK-N-MC.bNAT transfectants exhibited uptake and release kinetics similar to those of the natural NAT-expressing cell line SK-N-BE(2c). Levels of [(131)I]MIBG uptake were 33% of those of the highest naturally NAT-expressing cell line SK-N-BE(2c). Growth delay assays using multicellular spheroids indicated that this degree of [(131)I]MIBG uptake was sufficient to inhibit growth at radioactive concentrations of 4 Mbq/ml.

CONCLUSIONS

These results demonstrate the feasibility of combining gene therapy with targeted radiotherapy to enhance uptake, and hence radiation dose, to neuroblastoma tumours using [(131)I]MIBG. With the appropriate delivery vehicle and tumour-specific control of expression, the introduction of noradrenaline transporter molecules may be a viable means of enhancing the response of neuroblastoma tumours to [(131)I]MIBG therapy.

Paid attendant carers hold important and unexpected roles which contribute to the lives of people with brain injury

OBJECTIVE

Paid attendant carers spend many hours assisting people with a brain injury. Despite this considerable responsibility, most carers receive little support or training and their roles are often ill-defined. This exploratory study set out to define the key roles of paid carers.

METHOD

Ten semi-structured interviews were conducted. Perspectives were sought from 10 participants: five people with a traumatic brain injury and five paid carers. A computer software package, NUD*IST was used during analysis to help identifvy and categorize commonly recurring themes.

RESULTS

Five major roles were identified: Attendant, Protector, Friend, Coach and Negotiator. Friendship was the most important aspect of the care relationship for three of the people with a brain injury, most of whom had lost their pre-injury friends and associates. Carers were required to negotiate frequently with clients and their families, and with other service providers. Sound communication skills were required.

CONCLUSION

In addition to further research, industry guidelines are required which take account of the wider suite of roles fulfilled by paid carers, address training and support needs, and occupational health and safety issues.

Anhydride modified cantharidin analogues: synthesis, inhibition of protein phosphatases 1 and 2A and anticancer activity

Two series of anhydride modified cantharidin analogues were synthesised and screened for their phosphatase inhibition (PP1 and PP2A) and cytotoxicity in various cancer cell lines (Ovarian A2780, ADDP; Osteosarcoma 143B; and Colon HCT116 and HT29). One series was synthesised by a novel, high yielding one-pot hydrogenation-ring-opening-esterification procedure, the other by acid catalysed acetal formation. Analogues 5-7 and 9 displayed moderate PP2A selectivity (ca. 5- to 20-fold) and inhibition typically in the low microM range (comparable, in some cases to cantharidin). The anticancer activity of these analogues varied with the cell line under study; however, many of them showed selective cytotoxicity for the colon tumour cell lines.

Corticotropin releasing hormone: therapeutic implications and medicinal chemistry developments

Corticotropin releasing hormone (CRH, sometimes known as CRF) is an endogenous 41 amino acid peptide that has been implicated in the onset of pregnancy, the 'fight or flight' response, in addition to a large number of physiological disorders. Recently, medicinal chemists have developed a number of potent and selective compounds that show promise in a vast array of therapeutic uses. Herein we review the current status of research.

A dose-ranging study of rapacuronium in pediatric patients

BACKGROUND

The aim of this study was to determine the dose or doses of the new rapid-onset, short-acting, neuromuscular blocking drug rapacuronium that would provide satisfactory conditions for tracheal intubation at 60 s in infants and children.

METHODS

Sixty-five infants (< 1 yr), 51 younger children (1-6 yr), and 49 older children (7-12 yr) were studied. Anesthesia was induced with thiopental-nitrous oxide-oxygen. Tracheal intubation was attempted 60 s after administration of one of five doses of rapacuronium (0.5, 1.0, 1.5, 2.0, or 2.5 mg/kg) and intubating conditions were assessed using a four-point scale. Following tracheal intubation, anesthesia was maintained with nitrous oxide-oxygen and alfentanil (12.5-50 microg/kg) as necessary. Neuromuscular transmission was monitored in an uncalibrated fashion using an acceleromyograph.

RESULTS

Intubating conditions were good or excellent at 60 s in all infants after doses of 1.5 mg/kg or more and in all younger and older children after doses of 2.0 mg/kg or more. The duration of action of rapacuronium was dose- and age-dependent. Mean times to reappearance of the third twitch of the train-of-four (TOF; T3) were less than 10 min in infants at doses of 1.5 mg/kg or less and in younger and older children at doses of 2.0 mg/kg or less. Recovery of T3 after 1.0-2.0 mg/kg rapacuronium was significantly slower in infants compared with younger (P = 0.001) and older (P = 0.02) children. Five adverse experiences were related to rapacuronium administration: Bronchospasm (two instances), tachycardia (one instance), and increased salivation (two instances). None were serious.

CONCLUSIONS

Doses of 1.5 and 2.0 mg/kg rapacuronium can produce satisfactory intubating conditions at 60 s in anesthetized infants and children, respectively, and are associated with a short duration of action.

Inspiratory vocal cord dysfunction, a new approach in treatment

Vocal cord dysfunction is a well recognized respiratory condition in which adduction of the vocal cords during either inspiration or expiration, or both, causes functional airways obstruction. Diagnosis is usually made by laryngofibreoscopy, however treatment of this condition has generally been unsatisfactory, requiring a multi-disciplinary approach consisting of speech therapy, psychological counselling, sedatives and anaesthetic agents. Here we use an innovative approach which requires relatively inexpensive and simple anaesthetic equipment in order to manipulate airways resistance and thus reduce any vocal cord dysfunction as it occurs. The patient involved found instant relief when using this simple device which is easy to use and is portable.

Pharmacophore development for corticotropin-releasing hormone: new insights into inhibitor activity

Corticotropin-releasing hormone (CRH) is an endogenous 41-amino acid peptide involved in a wide ranging series of systems including the brain, the coordination of the body's overall response to stress, and more recently as a crucial initiator in the onset of labor, also known as the placental clock. Although more physiological data on CRH is emerging shedding more light on the processes involved and their integration, the mode of action of the hormone and the postulated binding site(s) remain unknown. Recently, a number of small-molecular-weight ligands have emerged as potent antagonists but, as therapeutics, suffer from a lack of solubility. Additionally, despite a number of exhaustively large patents, the lack of structural diversity with these antagonists has enabled little scope for comprehensive and wide ranging studies into the structure of the binding sites of this hormone. As part of a program investigating new, structurally diverse antagonists and agonists of CRH, we have developed a preliminary pharmacophore based on the known small-molecular-weight ligands as an initial step in our program. This pharmacophore was validated by comparison with some of the compounds we postulated to be active.