Common methodological pitfalls in ICI pneumonitis risk prediction studies

Background

Pneumonitis is one of the most common adverse events induced by the use of immune checkpoint inhibitors (ICI), accounting for a 20% of all ICI-associated deaths. Despite numerous efforts to identify risk factors and develop predictive models, there is no clinically deployed risk prediction model for patient risk stratification or for guiding subsequent monitoring. We believe this is due to systemic suboptimal approaches in study designs and methodologies in the literature. The nature and prevalence of different methodological approaches has not been thoroughly examined in prior systematic reviews.

Methods

The PubMed, medRxiv and bioRxiv databases were used to identify studies that aimed at risk factor discovery and/or risk prediction model development for ICI-induced pneumonitis (ICI pneumonitis). Studies were then analysed to identify common methodological pitfalls and their contribution to the risk of bias, assessed using the QUIPS and PROBAST tools.

Results

There were 51 manuscripts eligible for the review, with Japan-based studies over-represented, being nearly half (24/51) of all papers considered. Only 2/51 studies had a low risk of bias overall. Common bias-inducing practices included unclear diagnostic method or potential misdiagnosis, lack of multiple testing correction, the use of univariate analysis for selecting features for multivariable analysis, discretization of continuous variables, and inappropriate handling of missing values. Results from the risk model development studies were also likely to have been overoptimistic due to lack of holdout sets.

Conclusions

Studies with low risk of bias in their methodology are lacking in the existing literature. High-quality risk factor identification and risk model development studies are urgently required by the community to give the best chance of them progressing into a clinically deployable risk prediction model. Recommendations and alternative approaches for reducing the risk of bias were also discussed to guide future studies.

929 The Incidence and Outcomes of Delayed Laparoscopic Cholecystectomy and Bile Duct Exploration on a Unit Adopting Index Admission Surgery for All Comers. a Review of 5750 Patients

Aim

The timing of laparoscopic cholecystectomy (LC) for emergency biliary admissions remains inconsistent with national and international guidelines. The perception that LC is difficult in acute cholecystitis and the popularity of the two-session approach to pancreatitis and suspected choledocholithiasis result in delayed management.

Method

Analysis of prospectively maintained data in a unit adopting “intention to treat” during the index admission. The aim was to study the incidence of previous biliary admissions and compare the operative difficulty, complications, and postoperative outcomes with index admission LC.

Results

Of 5750 LC performed 20.8% had previous biliary admissions; one in 93% and two or more in 7%. Most presented with biliary colic (39.6%) and acute cholecystitis (27.6%). A previous biliary history was associated with increased operative difficulty (p<0.001), longer operating times (86.9 v 68.1 minutes, p<0.001), more post-operative complications (7.5% v 5.2%, p=0.002) and longer hospital stay (8.1 v 5.5 days, p<0.001). However, conversion and mortality rates showed no significant differences.

Conclusion

Index admission LC is superior to interval cholecystectomy and should be offered to all patients fit for general anaesthesia regardless of presenting complaints. Subspecialisation should be encouraged as a major factor in optimising resource utilisation and post-operative outcomes of biliary emergencies.

437 Impact of COVID-19 on West of Scotland Colorectal Cancer Services

Aim

The coronavirus disease 19 (COVID-19) pandemic has driven unprecedented restriction of the National Health Service to accommodate additional pressures. Our aim was to analyse the impact of COVID-19 on the largest colorectal cancer (CRC) services in NHS Greater Glasgow & Clyde.

Method

Audit data collected from multidisciplinary team meetings for South Glasgow CRC service were accessed. We compared April-June 2020 (‘Lockdown group’) to corresponding months in 2019 (‘Control group’). Statistical analysis by unpaired T-test, Pearson’s χ2 test with post hoc analysis using adjusted Z scores and Bonferroni correction as appropriate.

Results

There was a 39.5% reduction in CRC diagnoses during lockdown (n = 49) compared to control (n = 81). There was a 34.1% reduction in CRC operations during lockdown (n = 27) compared to control (n = 52). The proportion of patients managed operatively did not differ between groups (p = 0.140). There was no difference in the number of days from diagnosis to first treatment between Lockdown and Control groups (Mean(SD): 40.1±35.3 and 43.2±42.9, p = 0.257). Primary care physicians were the main referral source for both lockdown (52%) and control groups (46%). The cessation of bowel screening programme saw no referrals in lockdown whereas it accounted for 21% of referrals in control group, p < 0.001).

Conclusions

We experienced dramatic reductions in CRC diagnoses during lockdown that was not only accounted for by the cessation of bowel screening. The diagnostic delay in the 39.5% ‘missed’ CRC patients may result in patient morbidity; a severe repercussion of COVID-19. The resurgence of COVID-19 cases poses a real threat to cancer services.

Ocular adverse events associated with immune checkpoint inhibitors: a novel multidisciplinary management algorithm

Ocular immune-related adverse events (IrAEs) associated with use of checkpoint inhibitors (CPIs) in cancer therapeutics are relatively rare, occurring in approximately 1% of treated patients. Recognition and early intervention are essential because the degree of tissue damage may be disproportionate to the symptoms, and lack of appropriate treatment risks permanent loss of vision. International guidelines on managing ocular IrAEs provide limited advice only. Importantly, local interventions can be effective and may avoid the need for systemic corticosteroids, thereby permitting the continuation of CPIs. We present a single institution case series of eight affected patients managed by our multidisciplinary team. Consistent with previously published series and case reports, we identified anterior uveitis as the most common ocular IrAE associated with CPIs requiring intervention. Based on our experience, as well as published guidance, we generated a simple algorithm to assist clinicians efficiently manage patients developing ocular symptoms during treatment with CPIs. In addition, we make recommendations for optimising treatment of uveitis and address implications for ongoing CPI therapy.

The value of bronchoscopy in patients with non-massive haemoptysis and a clear or benign computer tomogram scan

INTRODUCTION

The preferred diagnostic pathway for patients presenting with non-massive haemoptysis and normal or benign computer tomography (CT) radiological findings is unclear. The common approach is to investigate with both CT and bronchoscopy, irrespective of patient-specific factors. The value of performing fibreoptic bronchoscopy (FOB) in patients with non-massive haemoptysis and clear or benign CT findings remains undetermined. We aimed to investigate its value using a large retrospective case series.

MATERIAL AND METHODS

A retrospective review of 4376 FOBs performed in Northumbria Healthcare NHS Foundation Trust from January 2012 to December 2019 for patients presenting with haemoptysis and clear or benign CT findings. Statistical analysis was performed to describe patient-specific variables, clinical characteristics, pathological findings and subsequent management decisions.

RESULTS

A total of 4376 FOBs were performed during the study period, 275 were indicated to investigate non-massive haemoptysis. Two hundred and fifty-nine patients underwent a CT scan (158 before and 101 after FOB); 16 never had a CT because the treating physician did not feel it was necessary. About 258 CT scans showed normal anatomy. All patients underwent FOB; 192 showed normal findings. Bronchoscopic findings did not alter clinical management in 274 patients. One patient was referred to the ear, nose and throat department following the identification of polypoid vocal cord lesion which, following thorough investigation, was confirmed as benign.

CONCLUSION

FOB provides minimal value for identifying lung malignancies in patients with non-massive haemoptysis and a clear or benign CT scan irrespective of patient-specific risk factors. Cost savings would be associated if physicians altered practice accordingly.

Correlation of age-of-onset of Atopic Dermatitis with Filaggrin loss-of-function variant status

The genetic background of Atopic Dermatitis (AD) with chronic pruritus is complex. Filaggrin (FLG) is an essential gene in the epidermal barrier formation s. Loss-of-function (LOF) variants in FLG associated with skin barrier dysfunction constitute the most well-known genetic risk factor for AD. In this study, we focused on the frequency and effect of FLG loss-of-function variants in association with self-reported age-of-onset of AD. The dataset consisted of 386 whole-genome sequencing (WGS) samples. We observe a significant association between FLG LOF status and age-of-onset, with earlier age of onset of AD observed in the FLG LOF carrier group (p-value 0.0003, Wilcoxon two-sample test). We first tested this on the two most prevalent FLG variants. Interestingly, the effect is even stronger when considering all detected FLG LOF variants. Having two or more FLG LOF variants associates with the onset of AD at 2 years of age. In this study, we have shown enrichment of rare variants in the EDC region in cases compared with controls. Age-of-onset analysis shows not only the effect of the FLG and likely EDC variants in terms of the heightened risk of AD, but foremost enables to predict early-onset, lending further credence to the penetrance and causative effect of the identified variants. Understanding the genetic background and risk of early-onset is suggestive of skin barrier dysfunction etiology of AD with chronic pruritus

External validation of a predictive model of survival after cytoreductive nephrectomy for metastatic renal cell carcinoma

INTRODUCTION

Recent trials have emphasized the importance of a precise patient selection for cytoreductive nephrectomy (CN). In 2013, a nomogram was developed for pre- and postoperative prediction of the probability of death (PoD) after CN in patients with metastatic renal cell carcinoma. To date, the single-institutional nomogram which included mostly patients from the cytokine era has not been externally validated. Our objective is to validate the predictive model in contemporary patients in the targeted therapy era.

METHODS

Multi-institutional European and North American data from patients who underwent CN between 2006 and 2013 were used for external validation. Variables evaluated included preoperative serum albumin and lactate dehydrogenase levels, intraoperative blood transfusions (yes/no) and postoperative pathologic stage (primary tumour and nodes). In addition, patient characteristics and MSKCC risk factors were collected. Using the original calibration indices and quantiles of the distribution of predictions, Kaplan-Meier estimates and calibration plots of observed versus predicted PoD were calculated. For the preoperative model a decision curve analysis (DCA) was performed.

RESULTS

Of 1108 patients [median OS of 27 months (95% CI 24.6-29.4)], 536 and 469 patients had full data for the validation of the pre- and postoperative models, respectively. The AUC for the pre- and postoperative model was 0.68 (95% CI 0.62-0.74) and 0.73 (95% CI 0.68-0.78), respectively. In the DCA the preoperative model performs well within threshold survival probabilities of 20-50%. Most important limitation was the retrospective collection of this external validation dataset.

CONCLUSIONS

In this external validation, the pre- and postoperative nomograms predicting PoD following CN were well calibrated. Although performance of the preoperative nomogram was lower than in the internal validation, it retains the ability to predict early death after CN.

A phase II clinical study evaluating the efficacy and safety of neoadjuvant and adjuvant sunitinib in previously untreated patients with metastatic renal cell carcinoma (mRCC)(NeoSun)

e16087

Background: Sunitinib improves clinical outcomes in patients (pts) with mRCC. The single arm phase II NeoSun trial was designed to investigate its added value to nephrectomy, and to explore translational biological and imaging biomarkers. Methods: Pts with mRCC, scheduled for nephrectomy, no prior systemic therapy were recruited to receive 50mg OD sunitinib for 12 days, then post-surgery on a 4 week-on, 2 week-off, repeating 6 week cycle until disease progression. Diffusion-weighted, BOLD and dynamic contrast enhanced MR imaging (DW-MRI, DCE-MRI) and research blood sample collection were performed at baseline and end of 12 days. CT Imaging was performed at baseline, pre- and post-surgery, and then every 2 cycles. The primary endpoint was objective response rate (RECIST). Secondary endpoints included changes in diffusion DW-MRI, DCE- MRI of the tumour following 12 days suntinib, overall survival (OS), progression-free survival (PFS), response duration, surgical morbidity/mortality, and toxicity. Results: 14 pts received pre-surgery sunitinib, 71% (10/14) took the planned 12 doses. All 14 underwent total nephrectomy, and 13 recommenced sunitinib post-operatively. The mean number of post-surgery cycles was 11 (range 2 – 22). 58.3% (7/12) of pts achieved confirmed response (95% CI: 27.7 - 84.8%).91.7% (11/12) achieved objective clinical benefit (95% CI: 61.5 - 99.8%). Median OS is 33.7m and median PFS is 15.7m. Amongst those achieving PR/CR, median response duration is 8.7m. No unexpected surgical or sunitinib-related toxicities or complications were observed and the mean number of days from surgery to hospital discharge was 5.9 (range 3.0 – 17.0).There was a trend forOS to be better in pts with high baseline plasma VEGF-A (p = 0.06) or VEGF-C (p = 0.02) expression. A larger % tumour volume reduction after 12 days treatment is correlated with a smaller baseline % necrosis (coefficient = -0.51, p = 0.03). Conclusions: Sunitinib is effective and safe when given before and after nephrectomy to previously untreated pts with mRCC. Neoadjuvant studies such as NeoSun can safely explore translational biological and imaging endpoints. Clinical trial information: 2005-004502-82.

Prostatic relapse of an undifferentiated teratoma 24 years after orchidectomy

BACKGROUND

Non-seminomatous germ cell tumours make up about 40 % of all germ cell tumours, which in turn are the most common tumours in men aged 15-44 years. Low risk stage I non-seminomatous germ cell tumours, which are confined to the testes, are commonly treated by orchiectomy and surveillance. Up to 20 % of patients with this diagnosis relapse, usually within 1-2 years of follow up, but very rarely after more than 5 years. The most common sites of relapse are the retroperitoneal lymph nodes, the mediastinum, and the lungs. We describe a case of relapse in the prostate over 20 years after initial diagnosis, which has not been described in the literature so far.

CASE PRESENTATION

This report presents a 49-year-old white British man with relapsed testicular non-seminomatous germ cell tumour 22 years after initial treatment with orchidectomy only. He relapsed with a prostatic mass, haematospermia and back pain. His prostate specific antigen levels were within normal range. Alpha feto-protein and lactate dehydrogenase levels were elevated, and his human chorionic gonadotrophin levels were normal. A biopsy confirmed undifferentiated malignant tumour, shown immunohistochemically to be a yolk sac tumour. The patient was initially treated with bleomycin, etoposide and cisplatin chemotherapy, but developed bleomycin-related pulmonary side effects after two cycles. His treatment was changed and he completed four cycles of chemotherapy by receiving two cycles of etoposide, ifosfamide, and cisplatin. Post treatment blood tumour markers were normal, but a follow up computed tomography showed a mass in the base of the prostate, the trigone and the left distal ureter which was surgically resected. The histology from the surgical resection was of necrotic tissue. The patient is now in follow up at 3 years after treatment with no evidence of residual disease on computed tomography. His Alpha feto-protein, beta human chorionic gonadotrophin and lactate dehydrogenase levels are normal.

CONCLUSIONS

Very late relapse in stage I non-seminomatous germ cell tumours is extremely rare and the prostate is a highly unusual site of relapsed disease. For diagnosis of late relapse, this case confirms the value of serum biomarkers in germ cell tumours, in particular non-seminomatous germ cell tumours.

YouTube™ as a source of patient information about knee replacement surgery

Empowering patients or providing potentially dangerous information?

Restrictive anorexia nervosa and set-shifting in adolescents: a biobehavioral interface

PURPOSE

Set-shifting is a neurocognitive concept defined as the ability to switch tasks flexibly. Set-shifting scores are worse in adults with restrictive anorexia nervosa (AN-R) than in controls. Adolescence is a developmental period when young people must respond flexibly to new situations. The purpose of this study was to compare the set-shifting scores of 24 adolescent females with AN-R with 37 matched normal adolescent controls (ages, 14-20).

METHODS

Methods used for the study included sociodemographic, psychological, and biological data, and neurocognitive testing using the Behavior Rating of Executive Function - Self- and Parent-Reports, the Cambridge Neuropsychological Automated Battery, and the Wisconsin Card-Sorting Test. Statistical analyses included t-tests, multiple analysis of variance, and correlations.

RESULTS

Sociodemographic data and intelligence quotient of study and control subjects were similar. There were differences in body mass index and the Eating Disorder Inventory-3 evaluation. Significant differences in the composite score of set-shifting between the study and control groups were found using multiple analysis of variance.

CONCLUSION

Adolescent females with AN-R had significantly worse set-shifting scores than the control subjects. Future studies of adolescent AN-R subjects should include biological (functional magnetic resonance imaging) and neurocognitive measures to determine the mechanisms at the brain-behavioral interface so that treatment can be directed specifically to set-shifting deficits.

Molecular mechanisms for the activity of PX-478, an antitumor inhibitor of the hypoxia-inducible factor-1alpha

We have reported previously that PX-478 (S-2-amino-3-[4'-N,N,-bis(chloroethyl)amino]phenyl propionic acid N-oxide dihydrochloride) has potent antitumor activity against a variety of human tumor xenografts associated with the levels of the hypoxia-inducible factor-1alpha (HIF-1alpha) within the tumor. We now report that PX-478 inhibits HIF-1alpha protein levels and transactivation in a variety of cancer cell lines. Hypoxia-induced vascular endothelial growth factor formation was inhibited by PX-478, whereas baseline levels of vascular endothelial growth factor in normoxia were unaffected. Studies of the mechanism of PX-478 action showed that HIF-1alpha inhibition occurs in both normoxia and hypoxia and does not require pVHL or p53. In addition, PX-478 decreases levels of HIF-1alpha mRNA and inhibits translation as determined by 35S labeling experiments and reporter assays using the 5' untranslated region of HIF-1alpha. Moreover, to a lesser extent, PX-478 also inhibits HIF-1alpha deubiquitination resulting in increased levels of polyubiquitinated HIF-1alpha. The inhibitory effect of PX-478 on HIF-1alpha levels is primarily due to its inhibition of translation because HIF-1alpha translation continues in hypoxia when translation of most proteins is decreased. We conclude that PX-478 inhibits HIF-1alpha at multiple levels that together or individually may contribute to its antitumor activity against HIF-1alpha-expressing tumors.

Autophagic programmed cell death by selective catalase degradation

Autophagy plays a central role in regulating important cellular functions such as cell survival during starvation and control of infectious pathogens. Recently, it has been shown that autophagy can induce cells to die; however, the mechanism of the autophagic cell death program is unclear. We now show that caspase inhibition leading to cell death by means of autophagy involves reactive oxygen species (ROS) accumulation, membrane lipid oxidation, and loss of plasma membrane integrity. Inhibition of autophagy by chemical compounds or knocking down the expression of key autophagy proteins such as ATG7, ATG8, and receptor interacting protein (RIP) blocks ROS accumulation and cell death. The cause of abnormal ROS accumulation is the selective autophagic degradation of the major enzymatic ROS scavenger, catalase. Caspase inhibition directly induces catalase degradation and ROS accumulation, which can be blocked by autophagy inhibitors. These findings unveil a molecular mechanism for the role of autophagy in cell death and provide insight into the complex relationship between ROS and nonapoptotic programmed cell death.

Cerebral emboli and paradoxical embolisation in dementia: a pilot study

BACKGROUND

The causes of the common dementias remain unknown. Paradoxical embolisation of the cerebral circulation by venous thrombi passing through venous to arterial shunts (v-aCS) in the heart or pulmonary circulation is known to occur in cryptogenic stroke and post-operative confusion following hip replacement.

OBJECTIVES

To explore the role of paradoxical embolisation in dementia by investigating for cerebral emboli, venous to arterial circulation shunt (v-aCS) and carotid artery disease.

METHODS

Forty-one patients with dementia (24 Alzheimer's AD and 17 vascular VaD) diagnosed using DSM-IV criteria and 16 controls underwent transcranial Doppler (TCD) detection of spontaneous cerebral emboli in both middle cerebral arteries. A v-aCS was detected by intravenous injection of an air/saline ultrasound contrast at rest and after provocation by coughing and Valsalva's manoeuvre. Carotid artery disease was assessed by duplex imaging.

RESULTS

Cerebral emboli were detected in 11 (27.5%) dementia patients compared with one (7%) control (p = 0.15) with emboli being most frequent in VaD (41%) compared to controls [OR (95% CI): 10.5 (1.1, 98.9), p = 0.04]. A v-aCS was detected in 25 (61%) patients and seven (44%) controls (p = 0.24). In dementia patients with cerebral emboli; v-aCS was detected in seven (64%) and moderate to severe carotid stenosis was present in three (30%).

CONCLUSION

Cerebral emboli and v-aCS may be more frequent in patients with both VaD and AD than in controls, which suggest paradoxical embolisation as a potential mechanism for cerebral damage. This pilot study justifies a definitive case-control study.

Early Carotid Surgery in Acute Stroke: A Multicentre Randomised Pilot Study

BACKGROUND

Standard practice has been to delay carotid endarterectomy (CEA) for 2 months following acute stroke to avoid a perceived risk of cerebral haemorrhage. We investigated whether early CEA reduces early recurrent stroke and improves outcome in partial anterior circulation infarction (PACI).

METHODS

Patients with PACI and a Barthel score of >18 before stroke underwent carotid duplex and CT imaging within 7 days of stroke. Forty consenting patients fit for surgery with greater than 70% ipsilateral carotid stenosis were randomised, 19 to 'early' (within 24 h) and 21 to 'delayed' surgery (at 8 weeks). Modified Rankin and Barthel scores were recorded at 1 week, 2 months, 6 and 12 months.

RESULTS

Rankin scores improved more rapidly following 'early' surgery to a score of 1 (0-4) at 2 and 6 months compared with 2.5 and 2 (1-4), respectively, for delayed surgery (p < 0.05). Barthel scores were also significantly improved following 'early' CEA at 7 days but both groups reached a median score of 20 by 2 months. Four 'delayed' and 3 'early' patients suffered extension or recurrence of neurological deficits with 1 death in each group.

CONCLUSIONS

Early CEA within 7 days of ischaemic stroke improved functional outcome with earlier hospital discharge. A large multicentre study is needed to exclude the possibility that 'early' CEA increases the risk of cerebral haemorrhage or death.

Regulation of an ATG7-beclin 1 Program of Autophagic Cell Death by Caspase-8

Caspases play a central role in apoptosis, a well-studied pathway of programmed cell death. Other programs of death potentially involving necrosis and autophagy may exist, but their relation to apoptosis and mechanisms of regulation remains unclear. We define a new molecular pathway in which activation of the receptor-interacting protein (a serine-threonine kinase) and Jun amino-terminal kinase induced cell death with the morphology of autophagy. Autophagic death required the genes ATG7 and beclin 1 and was induced by caspase-8 inhibition. Clinical therapies involving caspase inhibitors may arrest apoptosis but also have the unanticipated effect of promoting autophagic cell death.

Antitumor activity and pharmacodynamic properties of PX-478, an inhibitor of hypoxia-inducible factor-1alpha

The hypoxia-inducible factor-1 (HIF-1) transcription factor is an important regulator of tumor response to hypoxia that include increased angiogenesis, glycolytic metabolism, and resistance to apoptosis. HIF-1 activity is regulated by the availability of the HIF-1alpha subunit, the levels of which increase under hypoxic conditions. PX-478 (S-2-amino-3-[4'-N,N,-bis(2-chloroethyl)amino]phenyl propionic acid N-oxide dihydrochloride) is an inhibitor of constitutive and hypoxia-induced HIF-1alpha levels and thus HIF-1 activity. We report that PX-478 given to mice suppresses HIF-1alpha levels in HT-29 human colon cancer xenografts and inhibits the expression of HIF-1 target genes including vascular endothelial growth factor and the glucose transporter-1. PX-478 shows antitumor activity against established (0.15-0.40 cm(3)) human tumor xenografts with cures of SHP-77 small cell lung cancer and log cell kills up to 3.0 for other tumors including HT-29 colon, PC-3 prostate, DU-145 prostate, MCF-7 breast, Caki-1 renal, and Panc-1 pancreatic cancers. Large (0.83 cm(3)) PC-3 prostate tumors showed 64% regression, which was greater than for smaller tumors. The antitumor response to PX-478 was positively correlated with tumor HIF-1alpha levels (P < 0.02) and was accompanied by massive apoptosis. The results show that PX-478 is an inhibitor of HIF-1alpha and HIF-1 transcription factor activity in human tumor xenografts and has marked antitumor activity against even large tumor xenografts, which correlates positively with HIF-1alpha levels.

Antitumor activity and pharmacodynamic properties of PX-478, an inhibitor of hypoxia-inducible factor-1α

The hypoxia-inducible factor-1 (HIF-1) transcription factor is an important regulator of tumor response to hypoxia that include increased angiogenesis, glycolytic metabolism, and resistance to apoptosis. HIF-1 activity is regulated by the availability of the HIF-1α subunit, the levels of which increase under hypoxic conditions. PX-478 (S-2-amino-3-[4′-N,N,-bis(2-chloroethyl)amino]phenyl propionic acid N-oxide dihydrochloride) is an inhibitor of constitutive and hypoxia-induced HIF-1α levels and thus HIF-1 activity. We report that PX-478 given to mice suppresses HIF-1α levels in HT-29 human colon cancer xenografts and inhibits the expression of HIF-1 target genes including vascular endothelial growth factor and the glucose transporter-1. PX-478 shows antitumor activity against established (0.15–0.40 cm3) human tumor xenografts with cures of SHP-77 small cell lung cancer and log cell kills up to 3.0 for other tumors including HT-29 colon, PC-3 prostate, DU-145 prostate, MCF-7 breast, Caki-1 renal, and Panc-1 pancreatic cancers. Large (0.83 cm3) PC-3 prostate tumors showed 64% regression, which was greater than for smaller tumors. The antitumor response to PX-478 was positively correlated with tumor HIF-1α levels (P &lt; 0.02) and was accompanied by massive apoptosis. The results show that PX-478 is an inhibitor of HIF-1α and HIF-1 transcription factor activity in human tumor xenografts and has marked antitumor activity against even large tumor xenografts, which correlates positively with HIF-1α levels.

Big brother is watching you--the ethical implications of electronic surveillance measures in the elderly with dementia and in adults with learning difficulties

Electronic surveillance has insidiously seeped into the fabric of society with little public debate about its moral implications. Perceived by some as a sinister Orwellian tool of repression and social control, the new technologies offer comfort and security to others; a benevolent parental watchful eye. Nervousness at being watched has been replaced increasingly by nervousness if we're not. These technologies are now becoming widely available to health care professionals who have had little opportunity to consider their ethical and moral ramifications. Electronic tagging and tracking devices may be seen as away of creating a more secure environment for vulnerable individuals such as the elderly with dementia or people with learning disabilities. However, the proponents of surveillance devices have met with considerable resistance and opposition,from those who perceive it as contrary to human dignity and freedom, with its connotations of criminal surveillance. In addition, they cite increased opportunity for abuse through, for example, the withdrawal of staff and financial resources from the care of people with complex needs. Implementing these technologies, therefore, has ethical implications for human rights and civil liberties. Optional alternatives to long-term and/or restrictive care, in the context of the practical difficulties involved in caring for those who represent a risk to themselves from wandering, demands rigorous exploration of pragmatic questions of morality, with reference to risk versus benefit strategies. Like reproductive cloning techniques, the mere existence of surveillance technologies is morally neutral. Rather it is the use (in this instance that of health and social care settings) to which it is put which has the potential for good or bad.

Comparative analysis of the Cosmed Quark b2 and K4b2 gas analysis systems during submaximal exercise

AIM

The purpose of this study was to compare the Cosmed K4b2 portable gas analysis system with the Cosmed Quark b2 metabolic cart.

METHODS

Twenty-one subjects attended one testing session that consisted of duplicate measurements of gas volumes and concentrations using both Cosmed gas analysis systems at 3 treadmill work rates; 1) 80m x min(-1), 0% grade, 2) 80m x min(-1), 5% grade, and 3) 80m x min(-1), 10% grade. Subjects walked for 3 min at each rate with one of the gas analysis systems attached to the facemask. The order of the procedures was randomized so that one system was used during both phases (1st or 2nd) of each work rate.

RESULTS

The results indicated that oxygen consumption (VO2) was significantly higher in the K4b2 compared to the Quark at 80m x min(-1), 0% grade (14.3+/-1.2 vs 13.6+/-1.2ml x kg(-1) x min(-1), respectively), (p<0.01). The fractional concentration of oxygen in expired air was also significantly lower in the K4b2 at 80 m x min(-1), 0% grade and 80 m x min(-1), 10% grade (p<0.05). There were no significant differences between systems for minute ventilation or carbon dioxide production. Despite the small mean bias in mean VO2 values (0.5-1.0ml x kg-1 x min(-1) higher) in the K4b2, all individual values were within the limits of agreement (mean difference+/-2 SD) as determined by the Bland-Altman technique.

CONCLUSION

The findings show a minimal bias in respiratory and metabolic parameters during bi-pedal locomotor activities at low to moderate exercise intensities in the two gas analysis systems.

Complementary and alternative groups contemplate the need for effectiveness, safety and cost-effectiveness research

OBJECTIVE

To examine the views of complementary and alternative medicine (CAM) groups on the need to demonstrate the effectiveness, safety and cost-effectiveness of their therapies and practices.

DESIGN

Qualitative interviews were conducted with 22 representatives of three CAM groups (chiropractic, homeopathy and Reiki). Qualitative content analysis was used to identify similarities and differences among and across groups.

SETTING

Ontario, Canada.

RESULTS

There were striking differences in the views of the three sets of respondents. The chiropractors agreed that it was essential for their group to provide scientific evidence that their interventions work, are safe and cost-effective. The leaders of the homeopathic group were divided on these points and the Reiki respondents showed virtually no interest in undertaking such research.

CONCLUSIONS

CAM groups that are more formally organized are most likely to recognize the importance of scientific research on their practices and therapies.

A randomised trial comparing cytomegalovirus antigenemia assay vs screening bronchoscopy for the early detection and prevention of disease in allogeneic bone marrow and peripheral blood stem cell transplant recipients

Preemptive antiviral therapy is often employed for CMV prevention following allogeneic BMT. Two common strategies are a screening bronchoscopy for CMV post-BMT or regular CMV antigenemia testing with ganciclovir administration for a positive result. In a randomised trial, we prospectively compared the efficacy of these two preemptive strategies. Consecutive patients were randomised to either a bronchoscopy for CMV on day 35 post BMT or weekly CMV antigenemia testing. If the bronchoscopy was positive for CMV, patients received preemptive ganciclovir for 8-10 weeks. If the antigenemia was positive for CMV, patients received a minimum of 2 weeks of preemptive ganciclovir. The primary endpoint was the development of active CMV disease. One hundred and eighteen allogeneic BMT patients were enrolled (60 in the antigenemia arm and 58 in the bronchoscopy arm). The two groups were comparable with respect to baseline demographic data, underlying disease, conditioning regimen, and immunosuppression. Active CMV disease developed in 7/58 (12.1%) patients in the bronchoscopy arm vs 1/60 patients (1.7%) in the CMV antigenemia arm (P = 0.022). Based on the screening test, 13.8% of patients received preemptive ganciclovir in the bronchoscopy arm vs 48.3% of patients in the antigenemia arm (P < 0.001). There was no significant difference in the rate of graft-versus-host disease, bacteremia, invasive fungal infections or mortality between the two groups. Preemptive therapy based on regular CMV antigenemia monitoring is superior to screening bronchoscopy for the prevention of CMV disease after allogeneic BMT.

Selective behaviors altered in plasminogen-deficient mice are reconstituted with intracerebroventricular injection of plasminogen

In vitro studies demonstrate a role for the plasminogen (Plg) system in neurological function and recently in vivo studies show a role of the Plg system in neurodegeneration after the injection of an excitotoxic agent. Differences in the development of neurological function, however, have not been demonstrated in the Plg-deficient (Plg-/-) mice compared to wild-type (WT) mice. The role of Plg system in neurological function may relate to remodeling which occurs in response to various environmental challenges. In this study, behaviors (open field, grooming, hind-leg gait, water maze, and acoustic startle reflex) were tested in the Plg-deficient and WT mice at 6-8 weeks of age. Grooming, a response to the stress of an open field or fur moistening, was increased in the Plg-/--deficient mice compared to WT mice, and the acoustic startle reflex (ASR) was markedly decreased in the Plg-/- mice. The reduced ASR in Plg-/- mice occurred in mice with a mixed C57BL:129 background or in mice with a C57BL background. Plg was required for the ASR, since a deficiency of the Plg activators, urokinase (uPA) or tissue Plg activator (tPA), did not cause a reduction in the ASR compared to their WT control. Infusion of Plg directly into the brain was effective in restoring the ASR in the Plg-/- mice, but had no effect on the ASR of WT mice. Peripheral bolus injections of Plg or infusion into the jugular vein were ineffective in restoring the ASR in the Plg-/- mice. These results indicate that Plg is required for the appropriate response to the environmental challenge of a sudden loud sound, and that the response can be restored in Plg-/- mice by directly infusing Plg into the brain.

In vitro and in vivo anticancer activities of synthetic macrocyclic ketone analogues of halichondrin B

Halichondrin B is a highly potent anticancer agent originally found in marine sponges. Although scarcity of the natural product has hampered efforts to develop halichondrin B as a new anticancer drug, the existence of a complete synthetic route has allowed synthesis of structurally simpler analogues that retain the remarkable potency of the parent compound. In this study, we show that two macrocyclic ketone analogues of halichondrir B, ER-076349 and ER-086526, have sub-nM growth inhibitory activities in vitro against numerous human cancer cell lines as well as marked in vivo activities at 0.1-1 mg/kg against four human xenografts: MDA-MB-435 breast cancer, COLO 205 colon cancer, LOX melanoma, and NIH: OVCAR-3 ovarian cancer. ER-076349 and ER-086526 induce G2-M cell cycle arrest and disruption of mitotic spindles, consistent with the tubulin-based antimitotic mechanism of halichondrin B. This is supported further by direct binding of the biotinylated analogue ER-040798 to tubulin and inhibition of tubulin polymerization in vitro by ER-076349 and ER-086526. Retention of the extraordinary in vitro and in vivo activity off halichondrin B in structurally simplified, fully synthetic analogues establishes the feasibility of developing halichondrin B-based agents as highly effective, novel anticancer drugs.

Effects of pattern orientation and number of symmetry axes on the detection of mirror symmetry in dot and solid patterns

It has been postulated that as the number of axes of symmetry in a pattern increases, so pattern 'goodness' increases. Recently, a distinction was made between two different theoretical accounts of regularity or 'goodness' in relation to patterns with mirror symmetry: the 'transformational' and the 'holographic' models. It was argued that the former predicts a 'goodness' ordering of four > three > two > one whereas the latter predicts four > two > three > one, where '>' means greater regularity or goodness. In three experiments, we have tested these predictions. In experiment 1, we measured percentage correct and reaction time to dot patterns which had one, two, three, or four axes of symmetry and were flashed for 150 ms. Experiment 2 was identical except that patterns were presented for 2000 ms. In experiment 3, dot patterns were replaced by solid shapes which also had one, two, three, or four axes of symmetry. Although it was found that stimuli with four axes clearly allowed superior performance to that of stimuli with one axis, results obtained with stimuli with two and three axes were almost identical and in between those obtained with one and four axes. The data thus support the suggestion that extra axes add 'goodness' to symmetrical patterns but not in a monotonic fashion.

Reporter gene expression for monitoring gene transfer

The use of reporters such as green fluorescent protein (GFP) and firefly luciferase permit highly sensitive and nondestructive monitoring of gene transfer and expression. Modifications in GFP which increase intensity and thermostability, as well as alter its spectral qualities, have facilitated the use of GFP in a variety of gene transfer methods. Improvements in imaging technologies and their increased application in biological research have allowed the expanded use of luciferase-based reporters in gene transformation, particularly in genetic screens and in monitoring temporal changes in gene expression.

Achieving dietary recommendations: whole-grain foods in the Food Guide Pyramid

The Food Guide Pyramid illustrates USDA's food guide developed to help people follow the Dietary Guidelines for Americans. Unlike earlier food guides, the new food guide specifies foods for a total diet; that is, it addresses both concerns about adequacy and moderation. The food guide recommends increased intakes of the vegetable, fruit, and grain groups with special emphasis on dark-green leafy vegetables, legumes, and whole-grain products. These foods are important sources of several vitamins and minerals, complex carbohydrates, and dietary fiber, and they are generally low in fat. Analyses of expected nutrient levels provided by the food guide diet patterns indicate that the nutrient contribution of whole-grain products is particularly important for diets at lower calorie levels. In these diets, it is recommended that at least half the number of servings in the grain group be whole-grain products. In all diets, it is recommended that several servings of whole-grain products be included each day. Average intakes of vegetables, fruits, and grain products are less than recommended. The pyramid graphic has been especially helpful in emphasizing to the public the importance of increased consumption of vegetables, fruits, and grain products for a healthful diet.

Atwater to the present: evolution of nutrition education

Atwater charted a new course for nutrition education 100 years ago by using the scientific process to develop dietary guidance to improve public health and well being. Each of the areas of research to which Atwater gave leadership--nutrient requirements, food composition, food consumption, and consumer economics--are essential components in the development of dietary guidance. The emerging science of nutrition was translated into recommendations for a healthful diet by Caroline Hunt in 1916 in the first USDA food guide. Other familiar food guides were the "Basic-7" developed in the 1940's and the "Basic-4" from the 1950's. These early guides focused primarily on getting enough nutrients. By 1970, research was providing evidence of the role of excessive intakes of certain food components in the etiology of chronic disease. With the release of the "Dietary Guidelines for Americans" in 1980, work began on a new food guide to address both concerns about nutritional adequacy and overconsumption. Research involved development of a new food guide and a graphic to illustrate it. Although the time since the release of the new Food Guide Pyramid has been short, its wide acceptance by the professional community, industry, and the media promises to make it an effective nutrition education tool.