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1.
BMC Cancer ; 22(1): 629, 2022 Jun 08.
Article in English | MEDLINE | ID: mdl-35672690

ABSTRACT

The phase III clinical study of adjuvant liposomal muramyl tripeptide (MTP-PE) in resected high-grade osteosarcoma (OS) documented positive results that have been translated into regulatory approval, supporting initial promise for innate immune therapies in OS. There remains, however, no new approved treatment such as MTP-PE for either metastatic or recurrent OS. Whilst the addition of different agents, including liposomal MTP-PE, to surgery for metastatic or recurrent high-grade osteosarcoma has tried to improve response rates, a mechanistic hiatus exists in terms of a detailed understanding the therapeutic strategies required in advanced disease. Here we report a Bayesian designed multi-arm, multi-centre, open-label phase II study with randomisation in patients with metastatic and/or recurrent OS, designed to investigate how patients with OS might respond to liposomal MTP-PE, either given alone or in combination with ifosfamide. Despite the trial closing because of poor recruitment within the allocated funding period, with no objective responses in eight patients, we report the design and feasibility outcomes for patients registered into the trial. We demonstrate the feasibility of the Bayesian design, European collaboration, tissue collection with genomic analysis and serum cytokine characterisation. Further mechanistic investigation of liposomal MTP-PE alone and in combination with other agents remains warranted in metastatic OS.


Subject(s)
Bone Neoplasms , Osteosarcoma , Acetylmuramyl-Alanyl-Isoglutamine/analogs & derivatives , Bayes Theorem , Biomarkers , Bone Neoplasms/pathology , Humans , Liposomes , Neoplasm Recurrence, Local/drug therapy , Osteosarcoma/pathology , Phosphatidylethanolamines
2.
Respir Care ; 67(5): 543-552, 2022 05.
Article in English | MEDLINE | ID: mdl-35318238

ABSTRACT

BACKGROUND: The perceptions of using noninvasive ventilation (NIV) during exercise in patients with COPD who are naïve to NIV is unknown. The present study aimed to examine the perceptions of using NIV during exercise in people with COPD and to determine the relationship between patient perceptions with both baseline patient characteristics and exercise outcomes. METHODS: During a trial examining the effect of NIV during exercise on dynamic hyperinflation in people with COPD who were naïve to NIV, participants completed a 5-point Likert scale questionnaire (scored strongly disagree -2 to strongly agree +2) before and after using NIV during exercise and a semi-structured interview after using NIV during exercise. RESULTS: Eighteen participants, mean age (SD) 69 (7) y, FEV1/FVC 0.44 (0.08), FEV1 39 (7)% predicted, completed the study. Prior to exercise with NIV, participants were neutral about NIV, (mean [SD]) (0.67[0.84]). After exercise with NIV, participants felt that NIV made breathing easier (1.00 [0.77]) and that it helped exercise (1.06 [0.64]). There were moderate correlations between feeling that NIV was comfortable or effective and a change in exercise endurance time (ρ = - 0.588, P = .02), isotime inspiratory capacity (ρ = 0.488, P = .03), and measures of resting hyperinflation (ρ = 0.603, \P = .02). Interviews revealed that despite feeling comfortable using NIV during exercise, NIV might be too complicated for patients to manage outside a supervised environment. CONCLUSIONS: Individuals with COPD, naïve to NIV, and using NIV during exercise for the first time reported a positive effect of NIV on breathlessness and exercise performance. Participants' perceived benefit of NIV correlated moderately with increased endurance time and resting hyperinflation and with a reduction in dynamic hyperinflation during exercise, suggesting that patient reports could also aid selection of those who will benefit from NIV during exercise.


Subject(s)
Noninvasive Ventilation , Pulmonary Disease, Chronic Obstructive , Aged , Dyspnea , Exercise Tolerance , Humans , Inspiratory Capacity , Middle Aged , Pulmonary Disease, Chronic Obstructive/therapy
4.
Lung Cancer ; 165: 124-132, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35123155

ABSTRACT

Over the last 10 years, with the development of culture-free bacterial identification techniques, understanding of how the microbiome influences diseases has increased exponentially and has highlighted potential opportunities for its use as a diagnostic biomarker and interventional target in many diseases including malignancy. Initial research focused on the faecal microbiome since it contains the densest bacterial populations and many other mucosal sites, such as the lungs, were until recently thought to be sterile. However, in recent years, it has become clear that the lower airways are home to a dynamic bacterial population sustained by the migration and elimination of microbes from the gastrointestinal and upper airway tracts. As in the gut, the lung microbiome plays an important role in regulating mucosal immunity and maintaining the balance between immune tolerance and inflammation. Studies to date have all shown that the lung microbiome undergoes significant changes in the setting of pulmonary disease. In lung cancer, animal models and small patient cohort studies have suggested that microbiome dysbiosis may not only impact tumour progression and response to therapy, particularly immunotherapy, but also plays a key role in cancer pathogenesis by influencing early carcinogenic pathways. These early results have led to concerted efforts to identify microbiome signatures that represent diagnostic biomarkers of early-stage disease and to consider modulation of the lung microbiome as a potential therapeutic strategy. Lung microbiome research is in its infancy and studies to date have been small, single centre with significant methodological variation. Large, multicentre longitudinal studies are needed to establish the clinical potential of this exciting field.

5.
Chest ; 160(6): 2066-2079, 2021 12.
Article in English | MEDLINE | ID: mdl-34224690

ABSTRACT

BACKGROUND: During exercise, dynamic hyperinflation (DH), measured by a reduction in inspiratory capacity (IC), increases exertional dyspnea and reduces functional capacity in many patients with severe COPD. Although noninvasive ventilation (NIV) during exercise can improve exercise duration, the effect on DH is unclear. RESEARCH QUESTIONS: In people with COPD, resting hyperinflation, and evidence of DH during exercise, does bilevel NIV during exercise reduce DH and increase endurance time compared with exercise with no NIV, and does NIV with an individually titrated expiratory positive airway pressure (T-EPAP) reduce DH and increase exercise endurance time more than NIV with standardized EPAP (S-EPAP) of 5 cm H2O? STUDY DESIGN AND METHODS: A randomized crossover trial in which investigators and participants were blinded between NIV interventions was performed. Participants (N = 19; FEV1 of 1.02 ± 0.24 L (39% ± 6% predicted) completed three constant work rate endurance cycle tests in random order-no NIV, NIV with S-EPAP, and NIV with T-EPAP-during exercise. Primary outcomes were isotime IC and exercise endurance time. Outcome measures from each intervention were compared at isotime and at end exercise by using a linear mixed-model analysis. RESULTS: Compared with no NIV, isotime IC and endurance time were greater with both NIV with S-EPAP (mean difference: 95% CI, 0.19 L [0.10-0.28]; 95% CI, 153 s [24-280], respectively) and T-EPAP (95% CI, 0.22 L [0.13-0.32]; 95% CI, 145 s [28-259], respectively). There was no difference between NIV with S-EPAP and NIV with T-EPAP. INTERPRETATION: In people with COPD and DH during exercise, NIV during exercise reduced DH and increased cycle endurance time. An S-EPAP of 5 cm H2O was adequate to obtain these benefits. TRIAL REGISTRY: Australian New Zealand Clinical Trials Registry; No.: ACTRN12613000804785; URL: http://www.anzctr.org.au.


Subject(s)
Dyspnea/prevention & control , Dyspnea/physiopathology , Exercise Tolerance/physiology , Noninvasive Ventilation/methods , Pulmonary Disease, Chronic Obstructive/physiopathology , Pulmonary Disease, Chronic Obstructive/rehabilitation , Aged , Cross-Over Studies , Female , Humans , Inspiratory Capacity/physiology , Male , Severity of Illness Index
6.
Eur J Cancer Care (Engl) ; 30(6): e13492, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34312918

ABSTRACT

OBJECTIVE: Lung cancer patients from ethnic minorities have poorer outcomes than their Caucasian counterparts. We compared lung cancer intervals between culturally and linguistically diverse (CALD) and Anglo-Australian patients to identify ethnic disparities. METHODS: This was a prospective, observational cohort study comprising a patient survey and reviews of patients' hospital and general practice records. Across three states, 577 (407 Anglo-Australian and 170 CALD) patients were recruited and their hospital records reviewed. The survey was returned by 189 (135 Anglo-Australian and 54 CALD) patients, and a review was completed by general practitioners (GPs) of 99 (76 Anglo-Australian and 23 CALD) patients. Survival and Cox regression analyses were conducted. RESULTS: CALD patients had longer hospital diagnostic interval [median 30 days, 95% confidence interval (CI) 26-34] than Anglo-Australian patients (median 17, 95% CI 14-20), p = 0.005, hazard ratio (HR) = 1.32 (95% CI 1.09-1.60). This difference persisted after relevant factors were taken into consideration, adjusted HR = 1.26 (95% CI 1.03-1.54, p = 0.022). CALD patients also reported longer prehospital intervals; however, these differences were not statistically significant. CONCLUSION: Target interventions need to be developed to address ethnic disparity in hospital diagnostic interval.


Subject(s)
Ethnicity , Lung Neoplasms , Australia , Humans , Prospective Studies , White People
7.
Transl Lung Cancer Res ; 9(4): 1667-1679, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32953540

ABSTRACT

Multidisciplinary care (MDC) is considered best practice in lung cancer care. Health care services have made significant investments in MDC through the establishment of multidisciplinary team (MDT) meetings. This investment is likely to be sustained in future. It is imperative that MDT meetings are efficient, effective, and sufficiently nimble to introduce new innovations to enable best practice. In this article, we consider the 'evidence-practice gaps' in the implementation of lung cancer MDC. These gaps were derived from the recurrent limitations outlined in existing studies and reviews. We address the contributions that implementation science and quality improvement can make to bridge these gaps by increasing translation and improving the uptake of innovations by teams.

8.
Support Care Cancer ; 27(2): 485-493, 2019 Feb.
Article in English | MEDLINE | ID: mdl-29980906

ABSTRACT

PURPOSE: Improving the coordination of care for people with lung cancer is a health priority. This study aimed to tailor an existing care coordination survey for a lung cancer population, investigate coordination experiences for patients who had received hospital-based treatment and identify any factors that may be associated with poor care coordination. METHODS: We conducted a cross-sectional survey of lung patients within two tertiary hospitals in Sydney, Australia. The Cancer Care Coordination Questionnaire for Patients (CCCQ-P) is a psychometrically valid and reliable survey originally developed for colorectal cancer. We pilot tested a survey adaptation with lung cancer patients, support group members and medical specialists (n = 49). A revised survey was mailed to eligible patients via their medical specialist. RESULTS: Fifty-three of 118 eligible participants (45%) completed the CCCQ-P; most had early-stage disease and were about 70 years old. Overall, participants reported positive experiences of care coordination (mean total score 78.1), with high scores on communication and navigation subscales. The most problematic areas related to administrative aspects of care coordination and communication and information provision. Two patient groups (those residing in regional and rural areas, or no experience with the health system prior to diagnosis) reported significantly lower scores on the navigation subscale. CONCLUSIONS: This study found that lung cancer patients' experience of care coordination was positive, but highlighted the need for strategies to assist patients living in rural areas, and those with no experience of the health care system. The CCCQ-P survey instrument can be used in future lung cancer studies.


Subject(s)
Delivery of Health Care/trends , Lung Neoplasms/diagnosis , Aged , Communication , Cross-Sectional Studies , Female , Humans , Lung Neoplasms/pathology , Male , Surveys and Questionnaires
9.
BMC Cancer ; 18(1): 754, 2018 Jul 21.
Article in English | MEDLINE | ID: mdl-30031382

ABSTRACT

BACKGROUND: Lung cancer is the leading cause of cancer mortality worldwide. Early diagnosis and treatment is a key factor in reducing mortality and improving patient outcomes. To achieve this, it is important to understand the diagnostic pathways of cancer patients. Patients from Culturally and Linguistically Diverse (CALD) are a vulnerable group for lung cancer with higher mortality rates than Caucasian patients. The aim of this study is to explore differences in the lung cancer diagnostic pathways between CALD and Anglo-Australian patients and factors underlying these differences. METHODS: This is a prospective, observational cohort study using a mixed-method approach. Quantitative data regarding time intervals in the lung cancer diagnostic pathways will be gathered via patient surveys, General practitioner (GP) review of general practice records, and case-note analysis of hospital records. Qualitative data will be gathered via structured interviews with lung cancer patients, GPs, and hospital specialists. The study will be conducted in five study sites across three states in Australia. Anglo-Australian patients and patients from five CALD groups (i.e., Arabic, Chinese, Greek, Italian and Vietnamese communities) will mainly be identified through the list of new cases presented at lung multidisciplinary team meetings. For the quantitative component, it is anticipated that 724 patients (362 Anglo-Australian and 362 CALD patients) will be recruited to obtain a final sample of 290 (145 per group) assuming a 50% patient survey completion rate and a 80% GP record review completion rate. For the qualitative component, 60 interviews with lung cancer patients (10 Anglo-Australian and 10 patients per CALD group), 20 interviews with GPs, and 20 interviews with specialists will be conducted. DISCUSSION: This is the first Australian study to compare the time intervals along the lung cancer diagnostic pathway between CALD and Anglo-Australian patients. The study will also explore the underlying patient, healthcare provider, and health system factors that influence the time intervals in the two groups. This information will improve our understanding of the effect of ethnicity on health outcomes among lung cancer patients and will inform future interventions aimed at early diagnosis and treatment for lung cancer, particularly patients from CALD backgrounds. TRIAL REGISTRATION: The project was retrospectively registered with Australian New Zealand Clinical Trials Registry (registration number: ACTRN12617000957392 , date registered: 4th July 2017).


Subject(s)
Cultural Diversity , Lung Neoplasms/diagnosis , Lung Neoplasms/ethnology , Australia , Clinical Protocols , Culture , General Practitioners , Humans , Lung Neoplasms/therapy , Prospective Studies , Time Factors
10.
J Clin Med ; 7(7)2018 Jun 29.
Article in English | MEDLINE | ID: mdl-29966246

ABSTRACT

The role of the respiratory physician in diagnosing lung cancer has increased in complexity over the last 20 years. Adenocarcinoma is now the prevailing histopathological sub-type of non-small cell lung cancer (NSCLC) resulting in more peripheral cancers. Conventional bronchoscopy is often not sufficient to obtain adequate tissue samples for diagnosis. Radiologically guided transthoracic biopsy is a sensitive alternative, but carries significant risks. These limitations have driven the development of complimentary bronchoscopic navigation techniques for peripheral tumour localisation and sampling. Furthermore, linear endobronchial ultrasound with transbronchial needle aspiration (EBUS-TBNA) is increasingly being chosen as the initial diagnostic procedure for those with central lesions and/or radiological evidence of node-positive disease. This technique can diagnose and stage patients in a single, minimally invasive procedure with a diagnostic yield equivalent to that of surgical mediastinoscopy. The success of molecular targeted therapies and immune checkpoint inhibitors in NSCLC has led to the increasing challenge of obtaining adequate specimens for accurate tumour subtyping through minimally invasive procedures. This review discusses the changing epidemiology and treatment landscape of lung cancer and explores the utility of current diagnostic options in obtaining a tissue diagnosis in this new era of precision medicine.

11.
BMJ Open ; 7(12): e018629, 2017 12 28.
Article in English | MEDLINE | ID: mdl-29288182

ABSTRACT

OBJECTIVES: Few interventions have been designed that provide standardised information to primary care clinicians about the diagnostic and treatment recommendations resulting from cancer multidisciplinary team (MDT) (tumour board) meetings. This study aimed to develop, implement and evaluate a standardised template for lung cancer MDTs to provide clinical information and treatment recommendations to general practitioners (GPs). Specific objectives were to (1) evaluate template feasibility (acceptability, appropriateness and timeliness) with GPs and (2) document processes of preimplementation, implementation and evaluation within the MDT setting. DESIGN: A mixed-method study design using structured interviews with GPs and qualitative documentation of project logs about implementation processes. SETTING: Two hospitals in Central Sydney, New South Wales, Australia. PARTICIPANTS: 61 GPs evaluated the template. Two lung cancer MDTs, consisting of 33 clinicians, and eight researchers participated in template development and implementation strategy. RESULTS: The MDT-reporting template appears to be a feasible way of providing clinical information to GPs following patient presentation at a lung cancer MDT meeting. Ninety-five per cent of GPs strongly agreed or agreed that the standardised template provided useful and relevant information, that it was received in a timely manner (90%) and that the information was easy to interpret and communicate to the patient (84%). Implementation process data show that the investment made in the preimplementation stage to integrate the template into standard work practices was a critical factor in successful implementation. CONCLUSIONS: This study demonstrates that it is feasible to provide lung cancer MDT treatment recommendations to GPs through implementation of a standardised template. A simple intervention, such as a standardised template, can help to address quality gaps and ensure that timely information is communicated between tertiary and primary care healthcare providers.


Subject(s)
Documentation/standards , General Practitioners , Interdisciplinary Communication , Lung Neoplasms/therapy , Patient Care Team/organization & administration , Quality Assurance, Health Care/standards , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , New South Wales , Surveys and Questionnaires , Young Adult
12.
Med J Aust ; 207(10): 424, 2017 Nov 20.
Article in English | MEDLINE | ID: mdl-29129171
14.
BMC Cancer ; 16: 629, 2016 08 12.
Article in English | MEDLINE | ID: mdl-27519597

ABSTRACT

BACKGROUND: Melanotic neuroectodermal tumor of infancy (MNTI) is exceptionally rare and occurs predominantly in the head and neck (92.8 % cases). The patient reported here is only the eighth case of MNTI presenting in an extremity, and the first reported in the fibula. CASE PRESENTATION: A 2-month-old female presented with a mass arising in the fibula. Exhaustive genomic, transcriptomic, epigenetic and pathological characterization was performed on the excised primary tumor and a derived cell line. Whole-exome analysis of genomic DNA from both the tumor and blood indicated no somatic, non-synonymous coding mutations within the tumor, but a heterozygous, unique germline, loss of function mutation in CDKN2A (p16(INK4A), D74A). SNP-array CGH on DNA samples revealed the tumor to be euploid, with no detectable gene copy number variants. Multiple chromosomal translocations were identified by RNA-Seq, and fusion genes included RPLP1-C19MC, potentially deregulating the C19MC cluster, an imprinted locus containing microRNA genes reactivated by gene fusion in embryonal tumors with multilayered rosettes. Since the presumed cell of origin of MNTI is from the neural crest, we also compared gene expression with a dataset from human neural crest cells and identified 185 genes with significantly different expression. Consistent with the melanotic phenotype of the tumor, elevated expression of tyrosinase was observed. Other highly expressed genes encoded muscle proteins and modulators of the extracellular matrix. A derived MNTI cell line was sensitive to inhibitors of lysine demethylase, but not to compounds targeting other epigenetic regulators. CONCLUSIONS: In the absence of somatic copy number variations or mutations, the fully transformed phenotype of the MNTI may have arisen in infancy because of the combined effects of a germline CDKN2A mutation, tumor promoting somatic fusion genes and epigenetic deregulation. Very little is known about the etiology of MNTI and this report advances knowledge of these rare tumors by providing the first comprehensive genomic, transcriptomic and epigenetic characterization of a case.


Subject(s)
Bone Neoplasms/genetics , Cyclin-Dependent Kinase Inhibitor p18/genetics , Fibula/pathology , Germ-Line Mutation , Neuroectodermal Tumor, Melanotic/genetics , Oncogene Proteins, Fusion/genetics , Cyclin-Dependent Kinase Inhibitor p16 , Female , Gene Expression Regulation, Neoplastic , Humans , Infant , Phosphoproteins/genetics , Ribosomal Proteins/genetics , Sequence Analysis, DNA , Sequence Analysis, RNA
15.
Sci Rep ; 6: 25191, 2016 04 29.
Article in English | MEDLINE | ID: mdl-27125900

ABSTRACT

Bi-phasic or diauxic growth is often observed when microbes are grown in a chemically defined medium containing two sugars (for example glucose and lactose). Typically, the two growth stages are separated by an often lengthy phase of arrested growth, the so-called lag-phase. Diauxic growth is usually interpreted as an adaptation to maximise population growth in multi-nutrient environments. However, the lag-phase implies a substantial loss of growth during the switch-over. It therefore remains unexplained why the lag-phase is adaptive. Here we show by means of a stochastic simulation model based on the bacterial PTS system that it is not possible to shorten the lag-phase without incurring a permanent growth-penalty. Mechanistically, this is due to the inherent and well established limitations of biological sensors to operate efficiently at a given resource cost. Hence, there is a trade-off between lost growth during the diauxic switch and the long-term growth potential of the cell. Using simulated evolution we predict that the lag-phase will evolve depending on the distribution of conditions experienced during adaptation. In environments where switching is less frequently required, the lag-phase will evolve to be longer whereas, in frequently changing environments, the lag-phase will evolve to be shorter.


Subject(s)
Carbohydrate Metabolism , Escherichia coli/growth & development , Escherichia coli/metabolism , Gene Expression Regulation, Bacterial , Biomass , Computer Simulation , Escherichia coli/genetics , Phosphotransferases/metabolism
16.
BMJ Open ; 5(5): e008046, 2015 May 18.
Article in English | MEDLINE | ID: mdl-25986641

ABSTRACT

INTRODUCTION: Lung cancer is the most common cancer worldwide, with 1.3 million new cases diagnosed every year. It has one of the lowest survival outcomes of any cancer because over two-thirds of patients are diagnosed when curative treatment is not possible. International research has focused on screening and community interventions to promote earlier presentation to a healthcare provider to improve early lung cancer detection. This paper describes the protocol for a phase II, multisite, randomised controlled trial, for patients at increased risk of lung cancer in the primary care setting, to facilitate early presentation with symptoms of lung cancer. METHODS/ANALYSIS: The intervention is based on a previous Scottish CHEST Trial that comprised of a primary-care nurse consultation to discuss and implement a self-help manual, followed by self-monitoring reminders to improve symptom appraisal and encourage help-seeking in patients at increased risk of lung cancer. We aim to recruit 550 patients from two Australian states: Western Australia and Victoria. Patients will be randomised to the Intervention (a health consultation involving a self-help manual, monthly prompts and spirometry) or Control (spirometry followed by usual care). Eligible participants are long-term smokers with at least 20 pack years, aged 55 and over, including ex-smokers if their cessation date was less than 15 years ago. The primary outcome is consultation rate for respiratory symptoms. ETHICS AND DISSEMINATION: Ethical approval has been obtained from The University of Western Australia's Human Research Ethics Committee (RA/4/1/6018) and The University of Melbourne Human Research Committee (1 441 433). A summary of the results will be disseminated to participants and we plan to publish the main trial outcomes in a single paper. Further publications are anticipated after further data analysis. Findings will be presented at national and international conferences from late 2016. TRIAL REGISTRATION NUMBER: Australian New Zealand Clinical Trial Registry ACTRN 1261300039 3752.


Subject(s)
Early Detection of Cancer , Health Behavior , Lung Neoplasms/diagnosis , Primary Health Care , Self Care , Smoking/adverse effects , Aged , Australia , Diagnostic Self Evaluation , Female , Humans , Lung Neoplasms/complications , Lung Neoplasms/etiology , Male , Middle Aged , Nurses , Patient Acceptance of Health Care , Referral and Consultation , Research Design , Spirometry , Thorax
17.
Respirology ; 20(6): 884-8, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25847500

ABSTRACT

There is an increasing trend for the use of multi-disciplinary teams (MDT) in the management of complex medical conditions. The latter may include various cancers, including lung cancer. However, the use of MDT is not restricted to cancer management, but may include complex conditions like diabetes and other non-malignant disorders. There is an increasing trend to use MDT in the investigation and management of patients with suspected or proven lung cancer. This review examines the evidence that supports the efficacy, or otherwise, of lung cancer management in a MDT as opposed to individual care, who should be a member of a lung cancer MDT, and the specific role of the respiratory physician in a lung cancer MDT. Although it may seem to make common sense to manage lung cancer in a MDT setting, there is actually little in the way of high quality data to support this concept. The logistic and ethical difficulties in researching this issue are highlighted in this review.


Subject(s)
Lung Neoplasms/diagnosis , Lung Neoplasms/therapy , Patient Care Team , Pulmonary Medicine , Humans
18.
Biosystems ; 125: 32-42, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25263683

ABSTRACT

Amorphous computing is a non-standard computing paradigm that relies on massively parallel execution of computer code by a large number of small, spatially distributed, weakly interacting processing units. Over the last decade or so, amorphous computing has attracted a great deal of interest both as an alternative model of computing and as an inspiration to understand developmental biology. A number of algorithms have been developed that can take advantage of the massive parallelism of this computing paradigm to solve specific problems. One of the interesting properties of amorphous computers is that they are robust with respect to the loss of individual processing units, in the sense that a removal of some of them should not impact on the computation as a whole. However, much less understood is to what extent amorphous computers are robust with respect to minor disturbances to the individual processing units, such as random motion or occasional faulty computation short of total component failure. In this article we address this question. As an example problem we choose an algorithm to calculate a straight line between two points. Using this example, we find that amorphous computers are not in general robust with respect to Brownian motion and noise, but we find strategies that restore reliable computation even in their presence. We will argue that these strategies are generally applicable and not specific to the particular AC we consider, or even specific to electronic computers.


Subject(s)
Algorithms , Computational Biology/methods , Computer Simulation , Models, Theoretical , Stochastic Processes , Developmental Biology , Motion
19.
EMBO Mol Med ; 4(8): 705-18, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22674894

ABSTRACT

Insulin-like growth factor 2 (IGF2) and the transformation related protein 53 (Trp53) are potent regulators of cell growth and metabolism in development and cancer. In vitro evidence suggests several mechanistic pathway interactions. Here, we tested whether loss of function of p53 leads to IGF2 ligand pathway dependency in vivo. Developmental lethality occurred in p53 homozygote null mice that lacked the paternal expressed allele of imprinted Igf2. Further lethality due to post-natal lung haemorrhage occurred in female progeny with Igf2 paternal null allele only if derived from double heterozygote null fathers, and was associated with a specific gene expression signature. Conditional deletion of Igf2(fl/fl) attenuated the rapid tumour onset promoted by homozygous deletion of p53(fl/fl) . Accelerated carcinoma and sarcoma tumour formation in p53(+/-) females with bi-allelic Igf2 expression was associated with reductions in p53 loss of heterozygosity and apoptosis. Igf2 genetic dependency of the p53 null phenotype during development and tumour formation suggests that targeting the IGF2 pathway may be useful in the prevention and treatment of human tumours with a disrupted Trp53 pathway.


Subject(s)
Carcinoma/epidemiology , Insulin-Like Growth Factor II/metabolism , Mice, Knockout/embryology , Sarcoma/epidemiology , Tumor Suppressor Protein p53/metabolism , Animals , Carcinoma/pathology , Female , Gene Deletion , Homozygote , Humans , Insulin-Like Growth Factor II/genetics , Male , Mice , Sarcoma/pathology , Survival Analysis , Tumor Suppressor Protein p53/genetics
20.
Aust N Z J Obstet Gynaecol ; 51(3): 220-4, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21631440

ABSTRACT

BACKGROUND: With improvement in clinical care and longer survival of patients with cystic fibrosis (CF), pregnancy has become commonplace. However, the impact of pregnancy on maternal health and fetal outcomes requires ongoing review. METHODS: A retrospective study of 20 pregnancies from 18 women with CF during the period 1995-2009 was performed. Changes in lung function, body mass index (BMI) and development of gestational diabetes were recorded. Fetal outcomes and maternal survival were examined, and the influence of pre-pregnancy parameters on outcomes was evaluated. RESULTS: Mean maternal age at pregnancy was 29±5 years with a mean pre-pregnancy forced expiratory volume in 1 s (FEV1) of 65.6±20.8% predicted. Eleven of 20 pregnancies had a pre-pregnancy FEV1 <60% predicted. During pregnancy, FEV1% predicted fell by 4.8% (CI 1.6-7.9), but recovered to baseline within 6 months post-partum. Mothers gained a mean weight of 7.6±3.2 kg, and gestational diabetes developed in 43% of women. All women delivered live births apart from one therapeutic abortion. Five infants were preterm, and two mature infants had low birth weight. Three mothers either died or required lung transplantation after pregnancy (range 2.5-8.0 years). FEV1 <60% predicted and BMI <20 kg/m(2) were significant predictors of fetal complications. CONCLUSION: Most women tolerated pregnancy well without major complications despite many having at least moderate lung function impairment. Pre-pregnancy FEV1 and BMI were important predictors of outcomes.


Subject(s)
Cystic Fibrosis/epidemiology , Pregnancy Complications/epidemiology , Pregnancy Outcome/epidemiology , Body Mass Index , Cystic Fibrosis/complications , Diabetes, Gestational/epidemiology , Female , Forced Expiratory Volume , Humans , Infant, Low Birth Weight , Infant, Newborn , Lung/physiology , Lung Transplantation/statistics & numerical data , Maternal Mortality , Pregnancy , Premature Birth/epidemiology , Retrospective Studies
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