A Study on Auto-Catalysis and Product Inhibition: A Nucleophilic Aromatic Substitution Reaction Catalysed within the Cavity of an Octanuclear Coordination Cage

The ability of an octanuclear cubic coordination cage to catalyse a nucleophilic aromatic substitution reaction on a cavity-bound guest was studied with 2,4-dinitrofluorobenzene (DNFB) as the guest/substrate. It was found that DNFB undergoes a catalysed reaction with hydroxide ions within the cavity of the cubic cage (in aqueous buffer solution, pH 8.6). The rate enhancement of kcat/kuncat was determined to be 22, with cavity binding of the guest being required for catalysis to occur. The product, 2,4-dinitrophenolate (DNP), remained bound within the cavity due to electrostatic stabilisation and exerts two apparently contradictory effects: it initially auto-catalyses the reaction when present at low concentrations, but at higher concentrations inhibits catalysis when a pair of DNP guests block the cavity. When encapsulated, the UV/Vis absorption spectrum of DNP is red-shifted when compared to the spectrum of free DNP in aqueous solution. Further investigations using other aromatic guests determined that a similar red-shift on cavity binding also occurred for 4-nitrophenolate (4NP) at pH 8.6. The red-shift was used to determine the stoichiometry of guest binding of DNP and 4NP within the cage cavity, which was confirmed by structural analysis with X-ray crystallography; and was also used to perform catalytic kinetic studies in the solution-state.

Studying manganese carbonyl photochemistry in a permanently porous metal-organic framework

Mn(diimine)(CO)3X (X = halide) complexes are critical components of chromophores, photo- and electrocatalysts, and photoactive CO-releasing molecules (photoCORMs). While these entities have been incorporated into metal-organic frameworks (MOFs), a detailed understanding of the photochemical and chemical processes that occur in a permanently porous support is lacking. Here we site-isolate and study the photochemistry of a Mn(diimine)(CO)3Br moiety anchored within a permanently porous MOF support, allowing for not only the photo-liberation of CO from the metal but also its escape from the MOF crystals. In addition, the high crystallinity and structural flexibility of the MOF allows crystallographic snapshots of the photolysis products to be obtained. We report these photo-crystallographic studies in the presence of coordinating solvents, THF and acetonitrile, showing the changing coordination environment of the Mn species as CO loss proceeds. Using time resolved experiments, we report complementary spectroscopic studies of the photolysis chemistry and characterize the final photolysis product as a possible Mn(ii) entity. These studies inform the chemistry that occurs in MOF-based photoCORMs and where these moieties are employed as catalysts.

The preservation of sarin and O,O'-diisopropyl fluorophosphate inside coordination cage hosts

The host-guest chemistry of O,O'-diisopropyl fluorophosphate (DFP), a phosphonofluoridate G-series chemical warfare agent simulant, was investigated in the presence of a number of octanuclear cubic coordination cage hosts. The aim was to demonstrate cage-catalysed hydrolysis of DFP at near neutral pH: however, two octanuclear coordination cages, HPEG (containing water-solubilising PEG groups) and HW (containing water-solubilising hydroxymethyl groups), were actually found to increase the lifetime of DFP in aqueous buffer solution (pH 8.7). Crystallographic analysis of DFP with a structurally related host cage revealed that DFP binds to windows in the cage surface, not in the internal cavity. The phosphorus-fluorine bond is directed into the cavity rather than towards the external environment, with the cage/DFP association protecting DFP from hydrolysis. Initial studies with the chemical warfare agent (CWA) sarin (GB) with HPEG cage in a buffered solution also showed a drastically reduced rate of hydrolysis for sarin when bound in the host cage. The ability of these cages to inhibit hydrolysis of these P-F bond containing organophosphorus guests, by encapsulation, may have applications in forensic sample preservation and analysis.

Prognostic stratification of HPV-associated oropharyngeal cancer based on CD103+ immune cell abundance in patients treated on TROG 12.01 and De-ESCALaTE randomized trials

BACKGROUND

High CD103+ intratumoral immune cell (ITIC) abundance is associated with better prognosis in unselected patients with human papilloma virus-associated oropharyngeal squamous cell carcinoma (HPV-associated OPSCC) treated with cisplatin and radiotherapy (CIS/RT). Substituting cetuximab (CETUX) for CIS with RT in HPV-associated OPSCC resulted in inferior efficacy. Our aim was to determine whether quantification of CD103 ITIC could be used to identify a population of HPV-associated OPSCC with superior prognosis.

PATIENTS AND METHODS

We pooled data from the TROG 12.01 and De-ESCALaTE randomized trials that compared CETUX/70GyRT with CIS/70GyRT in low-risk HPV-associated OPSCC: American Joint Committee on Cancer 7 stage III (excluding T1-2N1) or stage IV (excluding N2b-c if smoking history >10 pack-years and/or distant metastases), including all patients with available tumor samples. The primary endpoint was failure-free survival (FFS) in patients receiving CETUX/RT comparing CD103+ ITIC high (≥30%) versus low (<30%). High and low CD103 were compared using Cox regression adjusting for age, stage and trial.

RESULTS

Tumor samples were available in 159/182 patients on TROG 12.01 and 145/334 on De-ESCALaTE. CD103+ ITIC abundance was high in 27% of patients. The median follow-up was 3.2 years. The 3-year FFS in patients treated with CETUX/RT was 93% [95% confidence interval (CI) 79% to 98%] in high CD103 and 74% (95% CI 63% to 81%) in low CD103 [adjusted hazard ratio = 0.22 (95% CI 0.12-0.41), P < 0.001]. The 3-year overall survival in patients treated with CETUX/RT was 100% in high CD103 and 86% (95% CI 76% to 92%) in low CD103, P < 0.001. In patients treated with CIS/RT, there was no significant difference in FFS.

CONCLUSIONS

CD103+ ITIC expression separates CETUX/RT-treated low-risk HPV-associated OPSCC into excellent and poor prognosis subgroups. The high CD103 population is a rational target for de-intensification trials.

Priorities and preferences of advanced soft tissue sarcoma patients starting palliative chemotherapy: baseline results from the HOLISTIC study

INTRODUCTION

Palliative chemotherapy is the principal treatment of patients with advanced soft tissue sarcomas (STS); however prognosis is limited (median overall survival 12-19 months). In this setting, patient values and priorities are central to personalised treatment decisions.

PATIENTS AND METHODS

The prospective HOLISTIC study was conducted in the UK and the Netherlands assessing health-related quality of life in STS patients receiving palliative chemotherapy. Participants completed a questionnaire before starting chemotherapy, including attitudes towards quality of life (QoL) versus length of life (LoL), decisional control preferences, and decisional conflict. Chi-square and Fisher's exact tests were used to evaluate associations between patient characteristics and preferences.

RESULTS

One hundred and thirty-seven patients with advanced STS participated (UK: n = 72, the Netherlands: n = 65). Median age was 62 (27-79) years. Preference for extended LoL (n = 66, 48%) was slightly more common than preference for QoL (n = 56, 41%); 12 patients (9%) valued LoL and QoL equally (missing: n = 3). Younger patients (age <40 years) prioritised LoL, whereas two-thirds of older patients (aged ≥65 years) felt that QoL was equally or more important than LoL (P = 0.020). Decisional conflict was most common in patients who prioritised QoL (P = 0.024). Most patients preferred an active (n = 45, 33%) or collaborative (n = 59, 44%) role in treatment decisions. Gender, performance status, and country were significantly associated with preferred role. Concordance between preferred and actual role in chemotherapy decision was high (n = 104, 76%).

CONCLUSIONS

Heterogeneous priorities and preferences among advanced STS patients support personalised decisions about palliative treatment. Considering individual differences during treatment discussions may enhance communication and optimise patient-centred care.

MOF matrix isolation: cooperative conformational mobility enables reliable single crystal transformations

Obtaining structural information for highly reactive metal-based species can provide valuable insight into important chemical transformations or catalytic processes. Trapping these metal-based species within the cavities of porous crystalline hosts, such as metal-organic frameworks (MOFs), can stabilise them, allowing detailed structural elucidation by single crystal X-ray diffraction. Previously, we have used a bespoke flexible MOF, [Mn3L2L'] (MnMOF-1, where L = bis-(4-carboxyphenyl-3,5-dimethylpyrazolyl)methane and L = L', but L' has a vacant N,N'-chelation site), which has a chelating site capable of post-synthetically binding metal ions, to study organometallic transformations and fundamental isomerisation processes. This manuscript will report the underlying conformational flexibility of the framework, demonstrate the solvent dependency of post-synthetic metalation, and show that the structural flexibility of the linker site and framework are critical to controlling and achieving high levels of metal loading (and therefore site occupancy) during chemical transformations. From these results, a set of design principles for linker-based "matrix isolation" and structure determination in MOFs are derived.

Changes on soundscapes reveal impacts of wildfires in the fauna of a Brazilian savanna

Wildfire is a natural process in Brazilian savannas, but human activities alter fire regimes and threaten biodiversity. In this study, we used an ecoacoustics approach to assess fauna responses and recovery after wildfire in a Brazilian savanna. Six passive acoustic monitoring devices were used to record soundscapes before and after a wildfire a at burned and non-burned sites for one year and one month (September 2012 to September 2013). Power Spectral Density and the Acoustic Complexity Index were used to track biophony. Before the fire, the two sites had similar biophonic patterns (PSD: T = 1136, Z = 1.52, P = 0.12; ACI: T = 1117, Z = 1.10, P = 0.26) and soniferous species richness (Site 1 = 52 and Site 2 = 49). However, in the first two sessions of recordings after the fire, biophony became higher at the burned site during the day (PSD: T = 211 and 233; Z = 4.13 and 6.41; ACI: T = 120 and 469, Z = 5.14 and 7.07; all P < 0.00). During the night, biophony was usually higher at the non-burned site until May 2013 (PSD: T = 0 to 453; Z = 3.30 to 5.90; ACI: T = 333 to 491, Z = 3.80 to 4.93; all P < 0.00). Biophony became similar (P = 0.17 to 0.38) at the two sites or higher (P = 0.00 to 0.01) at the burned site from July to September 2013 (PSD: T = 55 to 1167; Z = 1.35 to 6.89; ACI: T = 719 to 1365, Z = 0.87 to 3.04). After the fire, a reduction of soniferous species at the burned site was observed for insects and bats. Both biophonic activity and soniferous species showed a tendency to recover one year after the fire, but there were still less species in September 2013 (non-burned = 43 and burned = 37) when compared to September 2012 at both sites (Site 1 = 52 and Site 2 = 49). Our results showed that changes in the natural regimes of fire can negatively impact the biodiversity and reinforce the need for monitoring protocols and inspection of wildfires.

Isolating reactive metal-based species in Metal-Organic Frameworks - viable strategies and opportunities

Structural insight into reactive species can be achieved via strategies such as matrix isolation in frozen glasses, whereby species are kinetically trapped, or by confinement within the cavities of host molecules. More recently, Metal-Organic Frameworks (MOFs) have been used as molecular scaffolds to isolate reactive metal-based species within their ordered pore networks. These studies have uncovered new reactivity, allowed observation of novel metal-based complexes and clusters, and elucidated the nature of metal-centred reactions responsible for catalysis. This perspective considers strategies by which metal species can be introduced into MOFs and highlights some of the advantages and limitations of each approach. Furthermore, the growing body of work whereby reactive species can be isolated and structurally characterised within a MOF matrix will be reviewed, including discussion of salient examples and the provision of useful guidelines for the design of new systems. Novel approaches that facilitate detailed structural analysis of reactive chemical moieties are of considerable interest as the knowledge garnered underpins our understanding of reactivity and thus guides the synthesis of materials with unprecedented functionality.

Identification of an excellent prognosis subset of human papillomavirus-associated oropharyngeal cancer patients by quantification of intratumoral CD103+ immune cell abundance

BACKGROUND

Accurate prognostic stratification of human papillomavirus-associated oropharyngeal cancers (HPV+OPSCC) is required to identify patients potentially suitable for treatment deintensification. We evaluated the prognostic significance of CD103, a surface marker associated with tissue-resident memory T cells (TRMs), in two independent cohorts of patients with HPV+OPSCC.

PATIENTS AND METHODS

The abundance and distribution of CD103+ immune cells were quantified using immunohistochemistry in a cohort of 189 HPV+OPSCC patients treated with curative intent and correlated with outcome. Findings were then validated in an independent cohort comprising 177 HPV+OPSCCs using univariable and multivariable analysis. Intratumoral CD103+ immune cells were characterized by multispectral fluorescence immunohistochemistry and gene expression analysis.

RESULTS

High intratumoral abundance of CD103+ immune cells using a  ≥30% cut-off was found in 19.8% of tumors in the training cohort of HPV+OPSCC patients and associated with excellent prognosis for overall survival (OS) with adjusted hazard ratio (HR) of 0.13 [95% confidence interval (CI) 0.02-0.94, P = 0.004]. In the independent cohort of HPV+OPSCCs, 20.4% had high intratumoral CD103+ abundance and an adjusted HR for OS of 0.16 (95% CI 0.02-1.22, P = 0.02). Five year OS of patients with high intratumoral CD103 was 100% across both cohorts. The C-statistic for the multivariate prognostic model with stage and age was significantly improved in both cohorts with the addition of intratumoral CD103+ cell abundance. On the basis of spatial location, co-expression of CD8 and CD69, and gene expression profiles, intratumoral CD103+ cells were consistent with TRMs.

CONCLUSION

Quantification of intratumoral CD103+ immune cell abundance provides prognostic information beyond that provided by clinical parameters such as TNM-staging, identifying a population of low risk HPV+OPSCC patients who are good candidates for trials of deintensification strategies.

Legal Aspects of Withdrawal of Therapy

The ability of intensive care to replace or support vital organ function has resulted in some patients surviving for long periods of time without improvement or a terminal event. In patients with no realistic chance of survival, decisions to withdraw or withhold life-sustaining therapies are commonly made.

Withdrawal of life support at the patient's request is lawful at common law and, in some states of Australia, by legal statute. In the intensive care setting though, it is more common for therapy to be withdrawn because the therapy is of no perceived benefit or not in the patient's best interests. However, in Australia there is little case law and very little legislation to direct the decision of whether to withdraw life-sustaining therapy on the grounds of futility or the patient's best interests.

The legislation that does exist in Australia, as well as law from other jurisdictions, largely places responsibility for the decision to withdraw therapy on the doctor in charge of the patient's care. However much weight is frequently placed on the wishes of the family.

Disagreements between family and clinicians over decisions to withdraw therapy are unusual and generally resolve over time. However if disagreement persists, it may be advisable to apply to the courts for a declaratory judgement, given the tenuous legal basis of withdrawal of life-sustaining therapy in Australia and the uncertainty over the courts’ view of the role of the patient's family in the decision-making process.

Anomalous twin boundaries in two dimensional materials

Twin boundary defects form in virtually all crystalline materials as part of their response to applied deformation or thermal stress. For nearly six decades, graphite has been used as a textbook example of twinning with illustrations showing atomically sharp interfaces between parent and twin. Using state-of-the-art high-resolution annular dark-field scanning transmission electron microscopy, we have captured atomic resolution images of graphitic twin boundaries and find that these interfaces are far more complex than previously supposed. Density functional theory calculations confirm that the presence of van der Waals bonding eliminates the requirement for an atomically sharp interface, resulting in long-range bending across multiple unit cells. We show these remarkable structures are common to other van der Waals materials, leading to extraordinary microstructures, Raman-active stacking faults, and sub-surface exfoliation within bulk crystals.

All materials subjected to mechanical deformation form low energy interfaces known as twin boundaries. Here, the authors investigate a variety of structural features that form upon bending atomically thin 2D-crystals, and predict distinct classes of post deformation microstructure based on their atomic arrangement, bend angle and flake thickness.

Pitfalls in the Management of Acute Adrenocortical Insufficiency: Discussion Paper

In patients with acute adrenocortical insufficiency prompt recognition and treatment may be life-saving. Treatment should be initiated immediately before confirmation of the diagnosis. As shown by these case reports, junior staff on acute medical and surgical services, to whom these patients usually first present, may not appreciate that (a) hyponatraemia and hyperkalaemia, in the absence of renal failure, should immediately suggest the diagnosis of adrenal insufficiency and (b) treatment should precede confirmation of the diagnosis. Attempts to correct hyperkalaemia due to adrenocortical insufficiency with insulin and infusions of dextrose is inappropriate and potentially dangerous but seems to be a not unusual mistake.

Route to improving Type 1 diabetes mellitus glycaemic outcomes: real-world evidence taken from the National Diabetes Audit

AIM

To use general practice-level data for England, available through the National Diabetes Audit, and primary care prescribing data to identify prescription treatment factors associated with variations in achieved glucose control (HbA_1c ).

METHODS

General practice-level National Diabetes Audit data on Type 1 diabetes, including details of population characteristics, services, proportion of people achieving target glycaemic control [HbA_1c ≤58 mmol/mol (7.5%)] and proportion of people at high glycaemic risk [HbA_1c >86 mmol/ml (10%)], were linked to 2013-2016 primary care diabetes prescribing data on insulin types and blood glucose monitoring for all people with diabetes.

RESULTS

A wide variation was found between the 10^th percentile and the 90^th percentile of general practices in both target glycaemic control (15.6% to 44.8%, respectively) and high glycaemic risk (4.8% to 28.6%, respectively). Our analysis suggests that, given the extrapolated total of 280 000 people with Type 1 diabetes in the UK, there may be the potential to increase the number of those within target glycaemic control from 80 000 to 101 000; 53% of this increase (11 000 people) would result from service improvements and 47% (10 000 people) from medication and technology changes. The same improvements would also provide the opportunity to reduce the number of people at high glycaemic risk from 42 000 to 26 500. A key factor associated with practice-level target HbA_1c achievement would be greater use of insulin pumps for up to an additional 56 000 people.

CONCLUSION

If the HbA_1c achievement rates in service provision, medication and use of technology currently seen in practices in the 90^th percentile were to be matched with regard to HbA_1c achievement rates in all general practices, glycaemic control might be improved for 36 500 people, with all the attendant health benefits.

Mining noise affects loud call structures and emission patterns of wild black-fronted titi monkeys

Anthropogenic noise pollution is increasing and can constrain acoustic communication in animals. Our aim was to investigate if the acoustic parameters of loud calls and their diurnal pattern in the black-fronted titi monkey (Callicebus nigrifrons) are affected by noise produced by mining activity in a fragment of Atlantic Forest in Brazil. We installed two passive acoustic monitoring devices to record sound 24 h/day, 7 days every 2 months, for a year; one unit was close to an opencast mine and the other 2.5 km away from it. Both sites presented similar habitat structures and were inhabited by groups of black-fronted titi monkeys. We quantified the noise at both sites by measuring the equivalent continuous sound level every 2 months for 1 year and quantified the emission of loud calls by titi monkeys through visual inspection of the recordings. The close site presented higher ambient noise levels than the far site. The quantitative comparison of loud calls of black-fronted titi monkeys between the two sites showed less calling activity in the site close to the mine than in the site further away. Approximately 20 % of the calls detected at the site close to the mine were masked by noise from truck traffic. Loud calls were longer at the site far from the mine and the diurnal patterns of vocal activity differed in the amount of calling as well as in the timing of peak calling activity between the two sites. Our results indicate that mining noise may constrain titi monkeys' long-distance vocal communication. Loud calls occupy a similar frequency band to mining noise, and an increase in ambient noise may be triggering black-fronted titi monkeys to adjust their long-distance communication patterns to avoid masking of their calls. Given that vocalizations are an important means of social interaction in this species, there are concerns about the impact of mining noise on populations exposed to this human activity.

Diagnostic Accuracy of T1-Weighted Dynamic Contrast-Enhanced-MRI and DWI-ADC for Differentiation of Glioblastoma and Primary CNS Lymphoma

BACKGROUND AND PURPOSE

Glioblastoma and primary CNS lymphoma dictate different neurosurgical strategies; it is critical to distinguish them preoperatively. However, current imaging modalities do not effectively differentiate them. We aimed to examine the use of DWI and T1-weighted dynamic contrast-enhanced-MR imaging as potential discriminative tools.

MATERIALS AND METHODS

We retrospectively reviewed 18 patients with primary CNS lymphoma and 36 matched patients with glioblastoma with pretreatment DWI and dynamic contrast-enhanced-MR imaging. VOIs were drawn around the tumor on contrast-enhanced T1WI and FLAIR images; these images were transferred onto coregistered ADC maps to obtain the ADC and onto dynamic contrast-enhanced perfusion maps to obtain the plasma volume and permeability transfer constant. Histogram analysis was performed to determine the mean and relative ADC_mean and relative 90th percentile values for plasma volume and the permeability transfer constant. Nonparametric tests were used to assess differences, and receiver operating characteristic analysis was performed for optimal threshold calculations.

RESULTS

The enhancing component of primary CNS lymphoma was found to have significantly lower ADC_mean (1.1 × 10^-3 versus 1.4 × 10^-3; P < .001) and relative ADC_mean (1.5 versus 1.9; P < .001) and relative 90th percentile values for plasma volume (3.7 versus 5.0; P < .05) than the enhancing component of glioblastoma, but not significantly different relative 90th percentile values for the permeability transfer constant (5.4 versus 4.4; P = .83). The nonenhancing portions of glioblastoma and primary CNS lymphoma did not differ in these parameters. On the basis of receiver operating characteristic analysis, mean ADC provided the best threshold (area under the curve = 0.83) to distinguish primary CNS lymphoma from glioblastoma, which was not improved with normalized ADC or the addition of perfusion parameters.

CONCLUSIONS

ADC was superior to dynamic contrast-enhanced-MR imaging perfusion, alone or in combination, in differentiating primary CNS lymphoma from glioblastoma.

Overview of Considerations for the Pediatric Patient Receiving Home Parenteral and Enteral Nutrition

Pediatric home nutrition support is a common practice used to provide children with impaired gastrointestinal function and their caregivers a therapeutic environment for the delivery of needed nutrition for proper growth and development. Specialized teams and equipment are now available to make this a successful experience for all involved. This paper will review items specific to the care of infants and children receiving both enteral and parenteral nutrition.

A Novel Methodology for Applying Multivoxel MR Spectroscopy to Evaluate Convection-Enhanced Drug Delivery in Diffuse Intrinsic Pontine Gliomas

BACKGROUND AND PURPOSE

Diffuse intrinsic pontine gliomas are inoperable high-grade gliomas with a median survival of less than 1 year. Convection-enhanced delivery is a promising local drug-delivery technique that can bypass the BBB in diffuse intrinsic pontine glioma treatment. Evaluating tumor response is critical in the assessment of convection-enhanced delivery of treatment. We proposed to determine the potential of 3D multivoxel (1)H-MR spectroscopy to evaluate convection-enhanced delivery treatment effect in these tumors.

MATERIALS AND METHODS

We prospectively analyzed 3D multivoxel (1)H-MR spectroscopy data for 6 patients with nonprogressive diffuse intrinsic pontine gliomas who received convection-enhanced delivery treatment of a therapeutic antibody (Phase I clinical trial NCT01502917). To compare changes in the metabolite ratios with time, we tracked the metabolite ratios Cho/Cr and Cho/NAA at several ROIs: normal white matter, tumor within the convection-enhanced delivery infusion site, tumor outside of the infused area, and the tumor average.

RESULTS

There was a comparative decrease in both Cho/Cr and Cho/NAA metabolite ratios at the tumor convection-enhanced delivery site versus tumor outside the infused area. We used MR spectroscopy voxels with dominant white matter as a reference. The difference between changes in metabolite ratios became more prominent with increasing time after convection-enhanced delivery treatment.

CONCLUSIONS

The comparative change in metabolite ratios between the convection-enhanced delivery site and the tumor site outside the infused area suggests that multivoxel (1)H-MR spectroscopy, in combination with other imaging modalities, may provide a clinical tool to accurately evaluate local tumor response after convection-enhanced delivery treatment.

Characterisation of two self-sufficient CYP102 family monooxygenases from Ktedonobacter racemifer DSM44963 which have new fatty acid alcohol product profiles

BACKGROUND

Two self-sufficient CYP102 family encoding genes (Krac_0936 and Krac_9955) from the bacterium Ktedonobacter racemifer DSM44963, which possesses one of the largest bacterial genomes, have been identified.

METHODS

Phylogenetic analysis of both the encoded cytochrome P450 enzymes, Krac0936 and Krac9955. Both enzymes were produced and their turnovers with fatty acid substrates assessed in vitro and using a whole-cell oxidation system.

RESULTS

Krac0936 hydroxylated straight chain, saturated fatty acids predominantly at the ω-1 and ω-2 positions using NADPH as the cofactor. Krac0936 was less active towards shorter unsaturated fatty acids but longer unsaturated acids were efficiently oxidised. cis,cis-9,12-Octadecadienoic and pentadecanoic acids were the most active substrates tested with Krac0936. Unusually Krac9955 showed very low levels of NAD(P)H oxidation activity though coupling of the reducing equivalents to product formation was high. The product distribution of tridecanoic, tetradecanoic and pentadecanoic acid oxidation by Krac9955 favoured oxidation at the ω-4, ω-5 and ω-6 positions, respectively.

CONCLUSION

Krac0936 and Krac9955 are self-sufficient P450 monooxygenases. Krac0936 has a preference for pentadecanoic acid over other straight chain fatty acids and showed little or no activity with dodecanoic or octadecanoic acids. Krac9955 preferably oxidised shorter fatty acids compared to Krac0936 with tridecanoic having the highest levels of product formation. Unlike Krac0936 and P450Bm3, Krac9995 showed lower activities with unsaturated fatty acids.

GENERAL SIGNIFICANCE

In this study of two of the CYP enzymes from K. racemifer we have shown that this bacterium from the Chloroflexi phylum contains genes which encode new proteins with novel activity.

T1-Weighted Dynamic Contrast-Enhanced MRI as a Noninvasive Biomarker of Epidermal Growth Factor Receptor vIII Status

BACKGROUND AND PURPOSE

Epidermal growth factor receptor variant III is a common mutation in glioblastoma, found in approximately 25% of tumors. Epidermal growth factor receptor variant III may accelerate angiogenesis in malignant gliomas. We correlated T1-weighted dynamic contrast-enhanced MR imaging perfusion parameters with epidermal growth factor receptor variant III status.

MATERIALS AND METHODS

Eighty-two consecutive patients with glioblastoma and known epidermal growth factor receptor variant III status who had dynamic contrast-enhanced MR imaging before surgery were evaluated. Volumes of interest were drawn around the entire enhancing tumor on contrast T1-weighted images and then were transferred onto coregistered dynamic contrast-enhanced MR imaging perfusion maps. Histogram analysis with normalization was performed to determine the relative mean, 75th percentile, and 90th percentile values for plasma volume and contrast transfer coefficient. A Wilcoxon rank sum test was applied to assess the relationship between baseline perfusion parameters and positive epidermal growth factor receptor variant III status. The receiver operating characteristic method was used to select the cutoffs of the dynamic contrast-enhanced MR imaging perfusion parameters.

RESULTS

Increased relative plasma volume and increased relative contrast transfer coefficient parameters were both significantly associated with positive epidermal growth factor receptor variant III status. For epidermal growth factor receptor variant III-positive tumors, relative plasma volume mean was 9.3 and relative contrast transfer coefficient mean was 6.5; for epidermal growth factor receptor variant III-negative tumors, relative plasma volume mean was 3.6 and relative contrast transfer coefficient mean was 3.7 (relative plasma volume mean, P < .001, and relative contrast transfer coefficient mean, P = .008). The predictive powers of relative plasma volume histogram metrics outperformed those of the relative contrast transfer coefficient histogram metrics (P < = .004).

CONCLUSIONS

Dynamic contrast-enhanced MR imaging shows greater perfusion and leakiness in epidermal growth factor receptor variant III-positive glioblastomas than in epidermal growth factor receptor variant III-negative glioblastomas, consistent with the known effect of epidermal growth factor receptor variant III on angiogenesis. Quantitative evaluation of dynamic contrast-enhanced MR imaging may be useful as a noninvasive tool for correlating epidermal growth factor receptor variant III expression and related tumor neoangiogenesis. This potential may have implications for monitoring response to epidermal growth factor receptor variant III-targeted therapies.

Identification of the Corticobulbar Tracts of the Tongue and Face Using Deterministic and Probabilistic DTI Fiber Tracking in Patients with Brain Tumor

BACKGROUND AND PURPOSE

The corticobulbar tract of the face and tongue, a critical white matter tract connecting the primary motor cortex and the pons, is rarely detected by deterministic DTI fiber tractography. Detection becomes even more difficult in the presence of a tumor. The purpose of this study was to compare identification of the corticobulbar tract by using deterministic and probabilistic tractography in patients with brain tumor.

MATERIALS AND METHODS

Fifty patients with brain tumor who underwent DTI were studied. Deterministic tractography was performed by using the fiber assignment by continuous tractography algorithm. Probabilistic tractography was performed by using a Monte Carlo simulation method. ROIs were drawn of the face and tongue motor homunculi and the pons in both hemispheres.

RESULTS

In all subjects, fiber assignment by continuous tractography was ineffectual in visualizing the entire course of the corticobulbar tract between the face and tongue motor cortices and the pons on either side. However, probabilistic tractography successfully visualized the corticobulbar tract from the face and tongue motor cortices in all patients on both sides. No significant difference (P < .08) was found between both sides in terms of the number of voxels or degree of connectivity. The fractional anisotropy of both the face and tongue was significantly lower on the tumor side (P < .03). When stratified by tumor type, primary-versus-metastatic tumors, no differences were observed between tracts in terms of the fractional anisotropy and connectivity values (P > .5).

CONCLUSIONS

Probabilistic tractography successfully reconstructs the face- and tongue-associated corticobulbar tracts from the lateral primary motor cortex to the pons in both hemispheres.

Frequency and prognostic significance of p16(INK4A) protein overexpression and transcriptionally active human papillomavirus infection in laryngeal squamous cell carcinoma

Background:

Human papillomavirus (HPV) infection is a powerful prognostic biomarker in a subset of head and neck squamous cell carcinomas, specifically oropharyngeal cancers. However, the role of HPV in non-oropharyngeal sites, such as the larynx, remains unconfirmed.

Methods:

We evaluated a cohort of 324 laryngeal squamous cell carcinoma (LSCC) patients for the expression of p16^INK4A (p16) protein by immunohistochemistry (IHC) and for high-risk HPV E6 and E7 mRNA transcripts by RNA in situ hybridisation (ISH). p16 expression and HPV status were correlated with clinicopathological features and outcomes.

Results:

Of 307 patients assessable for p16 IHC, 20 (6.5%) were p16 positive. Females and node-positive patients were more likely to be p16 positive (P<0.05). There were no other significant clinical or demographic differences between p16-positive and -negative cases. There was no difference in overall survival (OS) between p16-positive and -negative patients with 2-year survival of 79% in each group (HR=0.83, 95% CI 0.36–1.89, P=0.65). There was no statistically significant difference in failure-free survival (FFS) with 2-year FFS of 79% and 66% for p16-positive and -negative patients, respectively (HR=0.60, 95% CI 0.26–1.36, P=0.22). Only seven cases were found to be HPV RNA ISH positive, all of which were p16 IHC positive. There was no statistically significant difference in OS between patients with HPV RNA ISH-positive tumours compared with -negative tumours with 2-year survival of 86% and 71%, respectively (HR=0.76, 95% CI 0.23–2.5, P=0.65). The 2-year FFS was 86% and 59%, respectively (HR=0.62, 95% CI 0.19–2.03, P=0.43).

Conclusions:

p16 overexpression is infrequent in LSCC and the proportion of cases with high-risk HPV transcripts is even lower. There are no statistically significant correlations between p16 IHC or HPV RNA ISH status and OS or disease outcomes.

First-line anthracycline-based chemotherapy for angiosarcoma and other soft tissue sarcoma subtypes: pooled analysis of eleven European Organisation for Research and Treatment of Cancer Soft Tissue and Bone Sarcoma Group trials

BACKGROUND

Angiosarcoma is a rare subtype of soft tissue sarcoma (STS). Doxorubicinis the standard first-line chemotherapy for advanced STS. It is not known whether angiosarcoma response to anthracycline-based chemotherapy is different to other STS subtypes.

METHODS

Pooled data were analysed from 11 prospective randomised and non-randomized European Organisation for Research and Treatment of Cancer (EORTC) clinical trials of first-line anthracycline-based chemotherapy for advanced STS. Baseline patient characteristics, chemotherapy response, progression free survival (PFS) and overall survival (OS) of angiosarcoma patients were compared with other STS patients. Analysis was performed to identify factors prognostic for angiosarcoma response to chemotherapy, PFS and OS.

RESULTS

With a median follow-up of 4.2 years, data from 108 locally advanced and metastatic angiosarcoma patients and 2557 patients with other STS histologies were analysed. 25% of angiosarcoma patients had a complete or partial response to chemotherapy compared to 21% for other STS histotypes. The median PFS was 4.9 months and OS 9.9 months, which were not significantly different from other STS histotypes. In univariate analysis, bone metastases were an adverse prognostic factor for OS (hazard ratio (HR) 1.66, 95% confidence interval (CI) 1.03–2.67; p = 0.036). Tumour grade was as an adverse prognostic factor for PFS (HR 1.72, 95% CI 1.01–2.92; p = 0.044) and OS (HR 2.03; 95% CI 1.16–3.56; p = 0.011). Compared to single agent anthracyclines, doxorubicin + ifosfamide was associated with improved PFS (HR 0.53, 95% CI 0.33–0.86; p = 0.010) and OS (HR 0.53, 95% CI 0.32–0.90; p = 0.018).

CONCLUSIONS

Angiosarcoma response and survival following first-line anthracycline-based chemotherapy was similar to other STS histotypes. Our analysis provides a useful measure of angiosarcoma response to chemotherapy for comparison with future clinical trials.

Diffusion and perfusion MRI to differentiate treatment-related changes including pseudoprogression from recurrent tumors in high-grade gliomas with histopathologic evidence

BACKGROUND AND PURPOSE

Treatment-related changes and recurrent tumors often have overlapping features on conventional MR imaging. The purpose of this study was to assess the utility of DWI and DSC perfusion imaging alone and in combination to differentiate treatment-related effects and recurrent high-grade gliomas.

MATERIALS AND METHODS

We retrospectively identified 68 consecutive patients with high-grade gliomas treated by surgical resection followed by radiation therapy and temozolomide, who then developed increasing enhancing mass lesions indeterminate for treatment-related changes versus recurrent tumor. All lesions were diagnosed by histopathology at repeat surgical resection. ROI analysis was performed of the enhancing lesion on the ADC and DSC maps. Measurements made by a 2D ROI of the enhancing lesion on a single slice were recorded as ADCLesion and rCBVLesion, and measurements made by the most abnormal small fixed diameter ROI as ADCROI and rCBVROI. Statistical analysis was performed with Wilcoxon rank sum tests with P = .05.

RESULTS

Ten of the 68 patients (14.7%) had treatment-related changes, while 58 patients (85.3%) had recurrent tumor only (n = 19) or recurrent tumor mixed with treatment effect (n = 39). DWI analysis showed higher ADCLesion in treatment-related changes than in recurrent tumor (P = .003). DSC analysis revealed lower relative cerebral blood volume (rCBV)Lesion and rCBVROI in treatment-related changes (P = .003 and P = .011, respectively). Subanalysis of patients with suspected pseudoprogression also revealed higher ADCLesion (P = .001) and lower rCBVLesion (P = .028) and rCBVROI (P = .032) in treatment-related changes. Applying a combined ADCLesion and rCBVLesion model did not outperform either the ADC or rCBV metric alone.

CONCLUSIONS

Treatment-related changes showed higher diffusion and lower perfusion than recurrent tumor. Similar correlations were found for patients with suspected pseudoprogression.

A phase Ib/II translational study of sunitinib with neoadjuvant radiotherapy in soft-tissue sarcoma

Background:

Preoperative radiotherapy (RT) is commonly used to treat localised soft-tissue sarcomas (STS). Hypoxia is an important determinant of radioresistance. Whether antiangiogenic therapy can ‘normalise' tumour vasculature, thereby improving oxygenation, remains unknown.

Methods:

Two cohorts were prospectively enrolled. Cohort A evaluated the implications of hypoxia in STS, using the hypoxic tracer ¹⁸F-azomycin arabinoside (FAZA-PET). In cohort B, sunitinib was added to preoperative RT in a dose-finding phase 1b/2 design.

Results:

In cohort A, 13 out of 23 tumours were hypoxic (FAZA-PET), correlating with metabolic activity (r²=0.85; P<0.001). Two-year progression-free (PFS) and overall (OS) survival were 61% (95% CI: 0.44–0.84) and 87% (95% CI: 0.74–1.00), respectively. Hypoxia was associated with radioresistance (P=0.012), higher local recurrence (Hazard ratio (HR): 10.2; P=0.02), PFS (HR: 8.4; P=0.02), and OS (HR: 41.4; P<0.04). In Cohort B, seven patients received sunitinib at dose level (DL): 0 (50 mg per day for 2 weeks before RT; 25 mg per day during RT) and two patients received DL: −1 (37.5 mg per day for entire period). Dose-limiting toxicities were observed in 4 out of 7 patients at DL 0 and 2 out of 2 patients at DL −1, resulting in premature study closure. Although there was no difference in PFS or OS, patients receiving sunitinib had higher local failure (HR: 8.1; P=0.004).

Conclusion:

In STS, hypoxia is associated with adverse outcomes. The combination of sunitinib with preoperative RT resulted in unacceptable toxicities, and higher local relapse rates.

Multimodal microscopy using 'half and half' contact mode and ultrasonic force microscopy

Advances in the design and fabrication of multifunctional nanostructured materials require characterization techniques capable of simultaneously mapping multiple material properties with nanoscale resolution. We show that this can be achieved by combining nanomechanical information from ultrasonic force microscopy (UFM) with simultaneously acquired friction force and conductivity measurements from contact mode scanning. This utilizes a 'half and half' approach, where the AFM is operated alternatively in UFM and contact mode, with the switching rate sufficiently fast that simultaneous contact mode and UFM information is acquired at each pixel of an image. We demonstrate the potential of such a multimodal approach through its application to composite systems consisting of graphene islands on a copper surface, single-walled carbon nanotubes (SWNTs) on a silicon oxide substrate, and a graphene epoxy composite. The half and half approach enables the friction force to be measured without topographical cross-talk. Application to the SWNT sample reveals a further advantage; due to the superlubricity of UFM it enables standard contact mode imaging techniques to be applied to delicate samples.

Chronic kidney disease and diabetes in the national health service: a cross-sectional survey of the U.K. national diabetes audit

AIMS

We investigated the prevalence of chronic kidney disease and attainment of therapeutic targets for HbA1c and blood pressure in a large U.K.-based diabetes population.

METHODS

The U.K. National Diabetes Audit provided data from 1 January 2007 to 31 March 2008. Inclusion criteria were a documented urinary albumin:creatinine ratio and serum creatinine. Patients were stratified according to chronic kidney disease stage and albuminuria status. Chronic kidney disease was defined as an estimated glomerular filtration rate < 60 ml min(-1) 1.73 m(-2) , albuminuria or both. The proportions of patients achieving nationally defined glycaemic and systolic blood pressure targets were determined.

RESULTS

The cohort comprised 1,423,669 patients, of whom 868,616 (61%) met inclusion criteria. Of the patients analysed, 92.2% had Type 2 diabetes. A higher proportion of people with Type 2 diabetes (42.3%) had renal dysfunction compared with those with Type 1 diabetes (32.4%). Achievement of systolic blood pressure and HbA1c targets was poor. Among people with Type 1 diabetes, 67.8% failed to achieve an HbA1c < 58 mmol/mol (7.5%). Of all people with diabetes, 37.8% failed to achieve a systolic blood pressure < 140 mmHg. Blood pressure control was poor in advanced chronic kidney disease. For example, mean (standard deviation) systolic blood pressure rose from 128.6 (15.4) mmHg among people with Type 1 diabetes and normal renal function to 141.0 (23.6) mmHg in those with chronic kidney disease stage 5 and macroalbuminuria.

CONCLUSIONS

The high prevalence of chronic kidney disease and poor attainment of treatment targets highlights a large subset of the diabetes population at increased risk of cardiovascular mortality or progressive kidney disease.

Excess mortality during hospital stays among patients with recorded diabetes compared with those without diabetes

AIM

To assess the additional mortality during hospital admissions among patients with recorded diabetes and identify the extent of variation in English provider trusts.

METHODS

Inpatient admissions to all English hospitals between April 2010 and March 2012 were extracted from Hospital Episode Statistics. Binary logistic regression was used to standardize for age, sex, deprivation, method and reason for admission, co-morbidities and type of trust. Trust level standardized mortality ratios for inpatients with recorded diabetes were compared with those without recorded diabetes and with published measures of hospital mortality.

RESULTS

Of the 10 169 003 hospital admissions analysed, 11.2% had recorded diabetes, but 21.5% of inpatient deaths occurred in this group. After adjustment for case mix, hospital admissions in patients with recorded diabetes had a 6.4% greater risk of dying (2052 more deaths over 2 years) than would be expected compared with similar patients without recorded diabetes. The additional risk of death was significantly greater in smaller trusts. The highest additional risk of death was found in hospital admissions of younger female patients admitted electively. At provider trust level, 37.4% of variation in adjusted mortality in patients with recorded diabetes was explained by the mortality in those without recorded diabetes.

CONCLUSION

A diagnosis of diabetes has an adverse impact on hospital mortality that cannot be explained by usual case-mix adjustments, and the additional risk of dying is greatest among hospital admissions that would normally have a low risk of death. This implies that diabetes may override the usual risk factors for hospital mortality.

Obesity and kidney disease in type 1 and 2 diabetes: an analysis of the National Diabetes Audit

BACKGROUND

Obesity is increasingly prevalent in many countries. Obesity is a major risk factor for the development of type 2 diabetes but its relationship with diabetic kidney disease (DKD) remains unclear. Some studies have suggested that the metabolic syndrome (including obesity) may be associated with DKD in type 1 diabetes.

AIM

To investigate the association between obesity and DKD.

DESIGN

Retrospective cross-sectional study.

METHODS

National Diabetes Audit data were available for the 2007-08 cycle. Type 1 and 2 diabetes patients with both a valid serum creatinine and urinary albumin:creatinine ratio were included. DKD was defined as an estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m(2), albuminuria or both. Logistic regression was used to analyse associations of obesity (body mass index ≥30 kg/m(2)) and other variables including year of birth, year of diagnosis, ethnicity and stage of kidney disease.

RESULTS

A total of 58 791 type 1 and 733 769 type 2 diabetes patients were included in the analysis. After adjustment, when compared with type 1 diabetes patients with normal renal function those with DKD were up to twice as likely to be obese. Type 2 DKD patients were also more likely to be obese. For example, type 2 diabetes patients with an eGFR <15 ml/min/1.73 m(2) and normoalbuminuria, microalbuminuria or macroalbuminuria were all more likely to be obese; odds ratios (95% CI) 1.65 (1.3-2.1), 1.56 (1.28-1.92) and 1.27 (1.05-1.54), respectively.

CONCLUSION

This study has highlighted a strong association between obesity and kidney disease in type 1 diabetes and confirmed their association in type 2 diabetes.

Potential role of preoperative conventional MRI including diffusion measurements in assessing epidermal growth factor receptor gene amplification status in patients with glioblastoma

BACKGROUND AND PURPOSE

Epidermal growth factor receptor amplification is a common molecular event in glioblastomas. The purpose of this study was to examine the potential usefulness of morphologic and diffusion MR imaging signs in the prediction of epidermal growth factor receptor gene amplification status in patients with glioblastoma.

MATERIALS AND METHODS

We analyzed pretreatment MR imaging scans from 147 consecutive patients with newly diagnosed glioblastoma and correlated MR imaging features with tumor epidermal growth factor receptor amplification status. The following morphologic tumor MR imaging features were qualitatively assessed: 1) border sharpness, 2) cystic/necrotic change, 3) hemorrhage, 4) T2-isointense signal, 5) restricted water diffusion, 6) nodular enhancement, 7) subependymal enhancement, and 8) multifocal discontinuous enhancement. A total of 142 patients had DWI available for quantitative analysis. ADC maps were calculated, and the ADCmean, ADCmin, ADCmax, ADCROI, and ADCratio were measured.

RESULTS

Epidermal growth factor receptor amplification was present in 60 patients (40.8%) and absent in 87 patients (59.2%). Restricted water diffusion correlated with epidermal growth factor receptor amplification (P = .04), whereas the other 7 morphologic MR imaging signs did not (P > .12). Quantitative DWI analysis found that all ADC measurements correlated with epidermal growth factor receptor amplification, with the highest correlations found with ADCROI (P = .0003) and ADCmean (P = .0007).

CONCLUSIONS

Our results suggest a role for diffusion MR imaging in the determination of epidermal growth factor receptor amplification status in glioblastoma. Additional work is necessary to confirm these results and isolate new imaging biomarkers capable of noninvasively characterizing the molecular status of these tumors.

Variation in the recorded incidence of amputation of the lower limb in England

AIMS/HYPOTHESIS

The study aimed to explore the variation in recorded incidence of lower limb amputation in England.

METHODS

The incidences of amputations in adults with and without diabetes were determined from hospital episode statistics over 3 years to 31 March 2010 and compared between the 151 Primary Care Trusts (PCTs) in England.

RESULTS

There were 34,109 amputations, including 16,693 (48.9%) in people with diabetes. The incidence was 2.51 per 1,000 person-years in people with diabetes and 0.11 per 1,000 person-years in people without (relative diabetes risk 23.3). Incidence varied eightfold across PCTs in people both with diabetes (range 0.64-5.25 per 1,000 person-years) and without (0.03-0.24 per 1,000 person-years). Amputations in people with diabetes varied tenfold--both major (range 0.22-2.20 per 1,000 person-years) and minor (range 0.30-3.25 per 1,000 person-years). The incidences of minor and major amputations were positively correlated both in those with (r = 0.537, p < 0.0005) and without (r = 0.611, p < 0.0005) diabetes. Incidences of amputations were also correlated between people with and without diabetes (total amputations r = 0.433, p < 0.0005; major amputations r = 0.528, p < 0.0005). There was a negative correlation between the incidence of amputation and estimated prevalence of ethnic Asians. No association was found between the PCT incidence of either total amputations and general population prevalence of social deprivation (r = -0.138, p = 0.092) or smoking (r = 0.137, p = 0.096).

CONCLUSIONS/INTERPRETATION

Variation in amputation incidence occurs across England. Because of the similarity in amputation variation between people with and without diabetes the variation may reflect generic differences in local healthcare delivery, although racial factors may also contribute.

Somatotopic organization of motor pathways in the internal capsule: a probabilistic diffusion tractography study

BACKGROUND AND PURPOSE

The location of the motor pathways in the PLIC remains controversial. In the current study, we trace the fibers from the tongue, face, hand, and foot motor cortices by using probabilistic diffusion tractography and define their somatotopic organization in the PLIC.

MATERIALS AND METHODS

Twenty subjects were retrospectively studied. Fiber tracts were separately calculated between ROIs in the cerebral peduncle and in the 4 different motor regions in the precentral gyrus. Probabilistic connectivity maps were generated, and the voxel with the highest probability was designated as the position of the motor pathway. The PI and LI were defined as the relative anteroposterior and mediolateral locations of the motor pathways.

RESULTS

Tongue pathways were located anteromedial to face in 16 hemispheres (40%), with P < .05 for the PI and LI. Face pathways were located anteromedial to hand in 25 hemispheres (62.5%) with P < .05 for PI and LI. Hand pathways were anteromedial to foot in 14 hemispheres (35%) and anterior in 11 hemispheres (27.5%), with P < .05 for PI but P > .13 for LI. Group analysis showed that the somatotopic arrangement of the bilateral hemispheres was symmetric.

CONCLUSIONS

Probabilistic tractography demonstrated the anteroposterior alignment of the motor pathways along the long axis in the PLIC. Probabilistic tractography successfully tracked the motor pathways of the tongue, face, hand, and foot from the precentral gyrus through their intersection with the larger superior longitudinal fasciculus to the PLIC in all cases, overcoming limitations of standard (nonprobabilistic) tractography methods.

Analysis of circulating angiogenic biomarkers from patients in two phase III trials in lung cancer of chemotherapy alone or chemotherapy and thalidomide

BACKGROUND

Thalidomide has potent anti-inflammatory and anti-angiogenic properties. It was evaluated in combination with chemotherapy in two randomised placebo-controlled trials in patients with small cell lung cancer (SCLC, n=724) and advanced non-small cell lung cancer (NSCLC, n=722). Neither study demonstrated an improvement in overall survival with the addition of thalidomide to chemotherapy. This study investigated circulating angiogenic biomarkers in a subset of these patients.

METHODS

Serial plasma samples were collected in a cohort of patients enrolled in these two trials (n=95). Vascular endothelial growth factor (VEGF), soluble truncated form of VEGF receptor-2 (sVEGFR-2), interleukin-8 (IL-8), tumour necrosis factor-α (TNF-α), basic fibroblast growth factor (bFGF) and soluble intercellular adhesion molecule-1 (sICAM-1) levels were measured by enzyme-linked immunosorbent assays. Results were correlated with patient clinical data including stage, response rate and progression-free survival (PFS).

RESULTS

Baseline biomarker levels were not significantly different between SCLC and NSCLC. For pooled treatment groups, limited stage SCLC was associated with lower baseline VEGF (P=0.046), sICAM-1 (P=0.008) and IL-8 (P=0.070) than extensive stage disease. Low baseline IL-8 was associated with a significantly improved PFS in both SCLC and NSCLC (P=0.028), and a greater reduction in IL-8 was associated with a significantly improved tumour response (P=0.035). Baseline angiogenic factor levels, however, did not predict response to thalidomide.

CONCLUSION

Circulating angiogenic biomarkers did not identify patients who benefited from thalidomide treatment.

Potential utility of conventional MRI signs in diagnosing pseudoprogression in glioblastoma

OBJECTIVE

To examine the potential utility of conventional MRI signs in differentiating pseudoprogression (PsP) from early progression (EP).

METHODS

This retrospective study reviewed initial postradiotherapy MRI scans of 321 patients with glioblastoma undergoing chemotherapy and radiotherapy. A total of 93 patients were found to have new or increased enhancing mass lesions, raising the possibility of PsP. Final diagnosis of PsP or EP was established upon review of surgical specimens from a second resection or by clinical and radiologic follow-up. A total of 11 MRI signs potentially helpful in the differentiation between PsP and EP were examined on the initial post-RT MRI and were correlated with the final diagnosis through χ(2) or Fisher exact test.

RESULTS

Sixty-three (67.7%) of the 93 patients had EP, of which 22 (34.9%) were diagnosed by pathology. Thirty patients (32.3%) had PsP; 6 (16.7% of the 30) were diagnosed by pathology. Subependymal enhancement was predictive for EP (p = 0.001) with 38.1% sensitivity, 93.3% specificity, and 41.8% negative predictive value. The other 10 signs had no predictive value (p = 0.06-1.0).

CONCLUSIONS

Conventional MRI signs have limited utility in diagnosing PsP in patients with recently treated glioblastomas and worsening enhancing lesions. We did not find a sign with a high negative predictive value for PsP that would have been the most useful for the clinical physician. When present, subependymal spread of the enhancing lesion is a useful MRI marker in identifying EP rather than PsP.

Isolated diffusion restriction precedes the development of enhancing tumor in a subset of patients with glioblastoma

BACKGROUND AND PURPOSE

Most response criteria for patients with glioblastoma rely on increases in the contrast enhancing abnormality to determine tumor progression. Our aim was to determine retrospectively in patients with glioblastoma whether diffusion restriction can predict the development of new enhancing mass lesions.

MATERIALS AND METHODS

We reviewed the brain MR imaging scans (including DWI and ADC maps) of 208 patients with glioblastoma. Patients with restricted diffusion in or adjacent to the tumor were identified, with further analysis only performed on those patients with low-ADC lesions without enhancement. These patients were followed to determine if new concordant enhancement developed at the site of the low-ADC lesion. A Wilcoxon signed rank test, competing risk analysis, and Kaplan-Meier curves were used to compare the mean drop in ADC values, assess enhancement-free survival, and determine overall survival, respectively.

RESULTS

In 67 of the 208 patients (32.2%), visibly detectable restricted diffusion was seen during treatment. The study cohort was formed by the 27 patients with low-ADC lesions and no corresponding enhancement. Twenty-three (85.2%) patients developed gadolinium-enhancing tumor at the site of restricted diffusion a median of 3.0 months later (95% CI, 2.6-4.1 months). The mean decrease in ADC was 22.9% from baseline (P < .001). The 3-month enhancement-free survival probability was 0.481 (95% CI, 0.288-0.675). The 12-month overall survival probability was 0.521 (95% CI, 0.345-0.788). Restricted diffusion predicted enhancement regardless of antiangiogenic therapy with bevacizumab.

CONCLUSIONS

In a subset of patients with glioblastoma, development of a new focus of restricted diffusion during treatment may precede the development of new enhancing tumor.

Sphenoid masses in children: radiologic differential diagnosis with pathologic correlation

Childhood central skull base masses are rare, often difficult to diagnose, and have overlapping imaging findings. In this review, we provide an overview of the epidemiology, clinical findings, and management of pediatric sphenoid bone and sphenoid sinus masses with an emphasis on imaging findings that may help to differentiate lesions. Radiologic-pathologic correlation is provided. Finally, an imaging-based algorithm is presented as a guide to help radiologists narrow their differential diagnoses. Some of the entities discussed are virtually unique to the pediatric population; others occur rarely in this age group but should be considered in the appropriate clinical setting. Entities included in the discussion are grouped into 2 categories: those that cause nonaggressive osseous remodeling and those that are more commonly associated with aggressive bone changes. Mucocele, aneurysmal bone cyst, giant cell lesions, meningioma, and fibrous dysplasia tend to remodel bone, while entities such as chordoma, craniopharyngioma, rhabdomyosarcoma, sinonasal carcinoma, and neuroblastoma may cause more aggressive local bone changes.

Fishing for gaps in science: a bibliographic analysis of Brazilian freshwater ichthyology from 1986 to 2005

To investigate Brazilian freshwater ichthyology, from 1986 to 2005, a bibliometric analysis was conducted using abstracts downloaded from The Web of Science database searching for the keywords 'fish', 'pisces', 'teleostei' and the address field having the word 'Brazil'. The results of this study showed that Brazilian freshwater ichthyology publications have been increasing during the study period. This process is a consequence of a series of investments that the Brazilian Government has made. Furthermore, data analyses identified scientific areas where there was a lack of scientific knowledge (e.g. studies of species threatened with extinction and certain hydrologic basins). Research institutions from the north-east and northern region of Brazil had the lowest participation in scientific productivity, which was a reflection of their regions poorer economic situation. This study showed that scientific productivity in Brazilian ichthyology was a direct reflection of state investment in research. Furthermore, data in this study follow expected statistical probabilities, for example, fishes from the most diverse families were the most studied. Thus, the study shows that great progress has been made by Brazilian ichthyologists in the last 20 years; however, due to the mega diversity of fishes in Brazil, much remains to be done if many species are to become known to science and to be saved from extinction. This it seems will depend on continued and further investment by Brazilian Government funding agencies, as Brazilian ichthyologists have demonstrated their capacity to generate high quality information about their study species.

Bell-inequality violation with a triggered photon-pair source

Here we demonstrate, for the first time, violation of Bell's inequality using a triggered quantum dot photon-pair source without post-selection. Furthermore, the fidelity to the expected Bell state is increased above 90% using temporal gating to reject photons emitted at times when collection of uncorrelated light is more probable. A direct measurement of a CHSH Bell inequality is made showing a clear violation, highlighting that a quantum dot entangled photon source is suitable for communication exploiting nonlocal quantum correlations.

The North West Diabetic Pregnancy Audit: a practical system for multi-centre diabetic pregnancy audit

AIMS

Improving care for women with pre-gestational diabetic pregnancy is a core objective of the St Vincent Declaration and the Diabetes National Service Framework. The aim was to develop a practicable collaborative audit methodology for pre-gestational diabetic pregnancy.

METHODS

In 1999, care professionals in the north-west of England agreed standards and a simple monthly data collection system. Annual reports are compiled to summarize compliance with the standards. Each hospital receives an individualized report comprising tables and funnel plots that allow between-hospital comparisons.

RESULTS

Data on pre-gestational diabetic pregnancies are collated from 30 maternity units. Funnel plots and tables presented in the annual reports highlight any large differences between hospitals in booking and outcome measures for diabetic pregnancies.

CONCLUSIONS

The annual audit reports allow the assessment of current management and outcomes for diabetic pregnancies at a regional and local level. These reports help to identify areas where diabetic pregnancy care requires further attention.

Coherence of an entangled exciton-photon state

We study the effect of the exciton fine-structure splitting on the polarization entanglement of photon pairs produced by the biexciton cascade in a quantum dot. Entanglement persists despite separations between the intermediate energy levels of up to 4 microeV. Measurements show that entanglement of the photon pair is robust to the dephasing of the intermediate exciton state responsible for the first-order coherence time of either single photon. We present a theoretical framework incorporating the effects of spin scattering, background light, and dephasing. We distinguish between the first-order coherence time, and a parameter which we measure for the first time and define as the cross-coherence time.