Multi-center bonds as resonance hybrids: A real space perspective

The concept of distinct bonds within molecules has proven to be successful in rationalizing chemical reactivity. However, bonds are not a well-defined physical concept, but rather vague entities, described by different and often contradicting models. With probability density analysis, which can-in principle-be applied to any wave function, bonds are recovered as spin-coupled positions within most likely electron arrangements in coordinate space. While the wave functions of many systems are dominated by a single electron arrangement that is built from two-center two-electron bonds, some systems require several different arrangements to be well described. In this work, a range of these multi-center bonded molecules are classified and investigated with probability density analysis. The results are compared with valence bond theory calculations and data from collision-induced dissociation experiments.

Spanish version validation of the Marihuana Motives Measure in a drug-consuming adolescent sample

INTRODUCTION

Cannabis is the illicit drug mostly widely consumed by adolescents in Spain. The understanding of consumption motives is an important factor for intervention. In Spain, there are no available instruments for their evaluation, hence, the goal of this paper is to study the psychometric properties of the Marihuana Motives Measure (MMM) in a sample of adolescent consumers.

MATERIAL AND METHOD

Firstly, translation and back-translation was performed. A total of 228 adolescent consumers of cannabis were evaluated. Factorial analysis was conducted, and the reliability of the total scores and of each scale of the questionnaire was studied through Cronbach's alpha. Test-retest reliability was analyzed through interclass correlations. Validity evidence of the MMM was examined through correlations between current cannabis use, subjective consumption effects measured with the Addiction Research Center Inventory (ARCI), and personality measured with the Millon Adolescent Clinical Inventory (MACI).

RESULTS

High reliability was observed in total score of the MMM (Cronbach α = .86), and high and moderate reliability for each of the five factors obtained in the factorial analysis of the MMM, Social = .82, Enhancement = .72, Coping = .83, Expansion = .74, and Conformity = .64. Significant correlations were also observed between cannabis consumption motives and subjective effects, and between consumption motives and personality.

CONCLUSION

The Spanish version of the MMM shows a similar factorial structure as the one obtained by the original author, and its measures are reliable and valid for the study of cannabis consumption motives in adolescent consumer population.

Test of Gross Motor Development-3 (TGMD-3) with the Use of Visual Supports for Children with Autism Spectrum Disorder: Validity and Reliability

The validity and reliability of the Test of Gross Motor Development-3 (TGMD-3) were measured, taking into consideration the preference for visual learning of children with autism spectrum disorder (ASD). The TGMD-3 was administered to 14 children with ASD (4-10 years) and 21 age-matched typically developing children under two conditions: TGMD-3 traditional protocol, and TGMD-3 visual support protocol. Excellent levels of internal consistency, test-retest, interrater and intrarater reliability were achieved for the TGMD-3 visual support protocol. TGMD-3 raw scores of children with ASD were significantly lower than typically developing peers, however, significantly improved using the TGMD-3 visual support protocol. This demonstrates that the TGMD-3 visual support protocol is a valid and reliable assessment of gross motor performance for children with ASD.

Training paediatric healthcare staff in recognising, understanding and managing conflict with patients and families: findings from a survey on immediate and 6-month impact

BACKGROUND

Conflict is a recognised component of healthcare. Disagreements about treatment protocols, treatment aims and poor communication are recognised warning signs. Conflict management strategies can be used to prevent escalation, but are not a routine component of clinical training.

OBJECTIVE

To report the findings from a novel training intervention, aimed at enabling paediatric staff to identify and understand the warning signs of conflict, and to implement conflict resolution strategies.

DESIGN AND SETTING

Self-report measures were taken at baseline, immediately after the training and at 6 months. Questionnaires recorded quantitative and qualitative feedback on the experience of training, and the ability to recognise and de-escalate conflict. The training was provided in a tertiary teaching paediatric hospital in England over 18 months, commencing in June 2013.

INTERVENTION

A 4-h training course on identifying, understanding and managing conflict was provided to staff.

RESULTS

Baseline data were collected from all 711 staff trained, and 6-month follow-up data were collected for 313 of those staff (44%). The training was successful in equipping staff to recognise and de-escalate conflict. Six months after the training, 57% of respondents had experienced conflict, of whom 91% reported that the training had enabled them to de-escalate the conflict. Learning was retained at 6 months with staff more able than at baseline recognising conflict triggers (Fischer's exact test, p=0.001) and managing conflict situations (Pearson's χ² test, p=0.001).

CONCLUSIONS

This training has the potential to reduce substantially the human and economic costs of conflicts for healthcare providers, healthcare staff, patients and relatives.

Determination of pK(a) values of N-heterocyclic bases by fluorescence spectrophotometry

Fluorimetry is a relatively fast and accurate means of determining the dissociation constants of sparingly soluble heterocyclic bases. Complications can arise, however, from the dependence of fluorescence on excited-state as well as ground-state acid-base chemistry. Several approaches to circumventing or compensating for this difficulty are discussed. To demonstrate the utility of the methods, the pK(a), values of the conjugate acids of two bases are evaluated by the methods described.

Self-concept and physical self-concept in psychiatric children and adolescents

Self-concept is a widely examined construct in the area of psychiatric disorders. This study compared the Physical Self-Description Questionnaire (PSDQ) scores of adolescents with psychiatric disorders (N=103) with the results of a matched group of non-clinical adolescents (N=103). Self-concept and Physical self-concept were lower in the clinical than in the non-clinical group. Girls (N=59) scored lower than boys (N=44) in both groups. In the different diagnostic groups specific domains were affected in line with symptomatology, which has implications for therapy.

Body awareness in preschool children with psychiatric disorder

The purpose of this study was to investigate the body awareness of preschool children with a psychiatric disorder as measured by the test imitation of gestures (Bergès & Lézine, 1978), using the subsections for pointing to body parts (passive vocabulary) and naming body parts (active vocabulary). Seventy-seven children from 37 to 72 months of age with psychiatric disorders and 67 children without psychiatric disorders were matched for age and sex. A MANOVA indicated no significant interaction effects on the results between the sexes in the psychiatric group and the control group for passive vocabulary (F(1,150)=.59, p≥0.05) or for active vocabulary (F(1,150)=.61, p≥0.05). An ANOVA was conducted to determine the differences between the boys and girls for passive and active vocabulary, and the differences between the psychiatric group and the control group for passive and active vocabulary. No significant differences between the boys and girls for passive vocabulary (F(1,150)=1.968, p≥0.05) and active vocabulary (F(1,150)=1.57, p≥0.05) were found. There was a significant difference between the psychiatric and the control group for passive vocabulary (F(1,150)=9.511, p=0.002) and active vocabulary (F(1,150)=16.18, p=0.00009). The study provides support for the presence of language disorders associated with active and passive body awareness in children with psychiatric disorders compared to typically developing children.

18FDG-PET-CT in the follow-up of non-small cell lung cancer patients after radical radiotherapy with or without chemotherapy: an economic evaluation

BACKGROUND

The optimal follow-up strategy of non-small cell lung cancer (NSCLC) patients after curative intent therapy is still not established. In a recent prospective study with 100 patients, we showed that a FDG-PET-CT 3 months after radiotherapy (RT) could identify progression amenable for curative treatment in 2% (95% confidence interval (CI): 1-7%) of patients, who were all asymptomatic. Here, we report on the economic evaluation of this study.

PATIENTS AND METHODS

A decision-analytic Markov model was developed in which the long-term cost-effectiveness of 3 follow-up strategies was modelled with different imaging methods 3 months after therapy: a PET-CT scan; a chest CT scan; and conventional follow-up with a chest X-ray. A probabilistic sensitivity analysis was performed to account for uncertainty. Because the results of the prospective study indicated that the advantage seems to be confined to asymptomatic patients, we additionally examined a strategy where a PET-CT was applied only in the subgroup of asymptomatic patients. Cost-effectiveness of the different follow-up strategies was expressed in incremental cost-effectiveness ratios (ICERs), calculating the incremental costs per quality adjusted life year (QALY) gained.

RESULTS

Both PET-CT- and CT-based follow-up were more costly but also more effective than conventional follow-up. CT-based follow-up was only slightly more effective than conventional follow-up, resulting in an incremental cost-effectiveness ratio (ICER) of euro 264.033 per QALY gained. For PET-CT-based follow-up, the ICER was euro 69.086 per QALY gained compared to conventional follow-up. The strategy in which a PET-CT was only performed in the asymptomatic subgroup resulted in an ICER of euro 42.265 per QALY gained as opposed to conventional follow-up. With this strategy, given a ceiling ratio of euro 80.000, PET-CT-based follow-up had the highest probability of being cost-effective (73%).

CONCLUSIONS

This economic evaluation shows that a PET-CT scan 3 months after (chemo)radiotherapy with curative intent is a potentially cost-effective follow-up method, and is more cost-effective than CT alone. Applying a PET-CT scan only in asymptomatic patients is probably as effective and more cost-effective. It is worthwhile to perform additional research to reduce uncertainty regarding the decision concerning imaging in the follow-up of NSCLC.

Rectal prognostic index (RPI) to predict outcome of patients with locally advanced rectal cancer (LARC) treated with preoperative chemo-radiation (preop-CRT)

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Background: Preop-CRT followed by surgical resection is the standard for LARC. LARC patients (pts) treated with preop-CRT have 60–70% 5-year survival. Several pathologic features including T stage (yT), lymph node (N) ratio (# of positive N (Np) / # of N examined (Ne)) and tumor regression grade (TRG) have been shown to be independent prognostic markers. We developed a prognostic score to determine pts with low risk of recurrence after preop-CRT. Methods: Our sample set consists of 20 pts treated on in house trial of preop-CRT with paclitaxel. All pts had R0 resections and received 4 months of 5-FU based adjuvant chemotherapy. All pathology slides were independently reviewed by GI pathologist. RPI scale of -4 to 14 was developed based on the formula: RPI = T (1–4) + (Np/Ne x 10) - TRG (0–4). The low, intermediate and high risk for recurrence were predefined as RPI (≤1), (>1 and <5), (≥5). Results: Between 1999–2003, 20 pts were treated on the trial and had R0 resection. The data is summarized in table 1 . The 5yr disease-free (DFS) and overall survival (OS) rate of all pts were 62 and 77%. Two pts (10%) achieved complete pathological response. Low, intermediate and high risk RPI was noted in 50, 35, and 15 % of pts. The 5yr DFS and OS for low, intermediate and high risk groups were 75, 42, 33 % and 86, 71 and 33% respectively.Conclusions: RPI can accurately predict a subset of pts with low risk of recurrence after preop-CRT. Majority of pts in this cohort have low risk RPI and have a favorable outcome (5yr survival rate of 86%). RPI could be very helpful in designing future trials tailoring adjuvant chemotherapy based on risk of recurrence. We are validating this data with a larger, independent group of LARC patients from our cancer registry (N=30) and this data will be available for presentation. Since RPI only requires the final pathology after CRT, it should be readily reproducible in future prospective studies across different institutions.

[Table: see text]

No significant financial relationships to disclose.

Identification of residual metabolic-active areas within individual NSCLC tumours using a pre-radiotherapy (18)Fluorodeoxyglucose-PET-CT scan

BACKGROUND AND PURPOSE

Non-small cell lung cancer (NSCLC) tumours are mostly heterogeneous. We hypothesized that areas within the tumour with a high pre-radiation (18)F-deoxyglucose (FDG) uptake, could identify residual metabolic-active areas, ultimately enabling selective-boosting of tumour sub-volumes.

MATERIAL AND METHODS

Fifty-five patients with inoperable stage I-III NSCLC treated with chemo-radiation or with radiotherapy alone were included. For each patient one pre-radiotherapy and one post-radiotherapy FDG-PET-CT scans were available. Twenty-two patients showing persistent FDG uptake in the primary tumour after radiotherapy were analyzed. Overlap fractions (OFs) were calculated between standardized uptake value (SUV) threshold-based auto-delineations on the pre- and post-radiotherapy scan.

RESULTS

Patients with residual metabolic-active areas within the tumour had a significantly worse survival compared to individuals with a complete metabolic response (p=0.002). The residual metabolic-active areas within the tumour largely corresponded (OF>70%) with the 50%SUV high FDG uptake area of the pre-radiotherapy scan. The hotspot within the residual area (90%SUV) was completely within the GTV (OF=100%), and had a high overlap with the pre-radiotherapy 50%SUV threshold (OF>84%).

CONCLUSIONS

The location of residual metabolic-active areas within the primary tumour after therapy corresponded with the original high FDG uptake areas pre-radiotherapy. Therefore, a single pre-treatment FDG-PET-CT scan allows for the identification of residual metabolic-active areas.

HI-CHART: a phase I/II study on the feasibility of high-dose continuous hyperfractionated accelerated radiotherapy in patients with inoperable non-small-cell lung cancer

PURPOSE

To determine the feasibility of high-dose continuous hyperfractionated accelerated radiotherapy in patients with inoperable non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

In a prospective, Phase I/II study, according to the risk for radiation pneumonitis, three risk groups were defined: V(20) <25%, V(20) 25-37%, and V(20) >37%. The dose was administered in three steps from 61.2 Gy/34 fractions/23 days to 64.8 Gy/36 fractions/24 days to 68.40 Gy/38 fractions/25 days (1.8 Gy b.i.d. with 8-h interval), using a three-dimensional conformal technique. Only the mediastinal lymph node areas that were positive on the pretreatment (18)F-deoxy-D-glucose positron emission tomography scan were included in the target volume. The primary endpoint was toxicity.

RESULTS

A total of 48 Stage I-IIIB patients were included. In all risk groups, 68.40 Gy/38 fractions/25 days could be administered. Maximal toxicity according to the risk groups was as follows: V(20) <25% (n = 35): 1 Grade 4 (G4) lung and 1 G3 reversible esophageal toxicity; V(20) 35-37% (n = 12): 1 G5 lung and 1 G3 reversible esophageal toxicity. For the whole group, local tumor recurrence occurred in 25% (95% confidence interval 14%-40%) of the patients, with 1 of 48 (2.1%; upper one-sided 95% confidence limit 9.5%) having an isolated nodal recurrence. The median actuarial overall survival was 20 months, with a 2-year survival rate of 36%.

CONCLUSIONS

High-dose continuous hyperfractionated accelerated radiotherapy up to a dose of 68.40 Gy/38 fractions/25 days (a biologic equivalent of approximately 80 Gy when delivered in conventional fractionation) in patients with inoperable NSCLC and a V(20) up to 37% is feasible.

Challenges to implementation of the new Coroners' (Amendment) Rules 2005: experience from a tertiary paediatric pathology centre

In the UK sudden unexpected childhood deaths are referred to Her Majesty's Coroner (HMC) for postmortem examination during which small tissue samples are obtained for diagnostic purposes. Recent changes to regulate tissue use include the Coroners' (Amendment) Rules 2005. We audited the impact of these at a specialist paediatric centre. A retrospective audit of HMC tissue forms for autopsies was performed between 1 June 2005 - 31 May 2006, with regard to the options provided to, and chosen by, parents. Of 213 coronial autopsies, 178 were non-forensic. Tissue forms were submitted pre-autopsy in 25 (14%). An additional 47 were received after sending follow-up letters for a total of 72/178 (40%). Forms varied between coroners, but most failed to distinguish between blocks, slides, and other tissue samples and 6/40 (15%) forms did not specifically allow an option for research consent. Forty-three (60%) parents opted for retention, with 34 (79%) also consenting to research. Only six (8%) requested return of tissue. A simple, unified tissue disposal form and information sheet for all HMC districts, which includes appropriate options, would ensure that parents' wishes are met, to achieve best practice, maximise sample availability for positive societal outcomes such as teaching and research, and to comply with new regulations.

Tumor volume combined with number of positive lymph node stations is a more important prognostic factor than TNM stage for survival of non-small-cell lung cancer patients treated with (chemo)radiotherapy

PURPOSE

The current tumor, node, metastasis system needs refinement to improve its ability to predict survival of patients with non-small-cell lung cancer (NSCLC) treated with (chemo)radiation. In this study, we investigated the prognostic value of tumor volume and N status, assessed by using fluorodeoxyglucose-positron emission tomography (PET).

PATIENTS AND METHODS

Clinical data from 270 consecutive patients with inoperable NSCLC Stages I-IIIB treated radically with (chemo)radiation were collected retrospectively. Diagnostic imaging was performed using either integrated PET-computed tomography or computed tomography and PET separately. The Kaplan-Meier method, as well as Cox regression, was used to analyze data.

RESULTS

Univariate survival analysis showed that number of positive lymph node stations (PLNSs), as well as N stage on PET, was associated significantly with survival. The final multivariate Cox model consisted of number of PLNSs, gross tumor volume (i.e., volume of the primary tumor plus lymph nodes), sex, World Health Organization performance status, and equivalent radiation dose corrected for time; N stage was no longer significant.

CONCLUSIONS

Number of PLNSs, assessed by means of fluorodeoxyglucose-PET, was a significant factor for survival of patients with inoperable NSCLC treated with (chemo)radiation. Risk stratification for this group of patients should be based on gross tumor volume, number of PLNSs, sex, World Health Organization performance status, and equivalent radiation dose corrected for time.

Maximal neutropenia during chemotherapy and radiotherapy is significantly associated with the development of acute radiation-induced dysphagia in lung cancer patients

BACKGROUND

Acute dysphagia is a distressing dose-limiting toxicity after concurrent chemoradiation or high-dose radiotherapy for lung cancer. We therefore identified factors associated with the occurrence of acute dysphagia in lung cancer patients receiving radiotherapy alone or combined with chemotherapy.

PATIENTS AND METHODS

Radiotherapy, chemotherapy and patient characteristics were analyzed using ordinal regression analysis as possible predictors for acute dysphagia (CTCAE 3.0) in 328 lung cancer patients treated with curative intent.

RESULTS

The most significant association was seen between the maximal grade of neutropenia during chemoradiation and dysphagia, with an odds ratio increasing from 1.49 [95% confidence interval (CI) 0.63-3.54, P = 0.362] for grade 1-2 neutropenia to 19.7 (95% CI 4.66-83.52, P < 0.001) for patients with grade 4 neutropenia. Twice-daily schedule, mean esophageal dose and administration of chemotherapy were significant predictive factors. By combining these factors, a high-performance predictive model was made. On an individual patient level, 64% of patients were correctly classified and only 1.2% of patients were misclassified by more than one grade.

CONCLUSIONS

The maximal neutrophil toxicity during concurrent chemotherapy and radiotherapy is strongly associated with the development of acute dysphagia. A multivariate predictive model was developed.

Omission of elective node irradiation on basis of CT-scans in patients with limited disease small cell lung cancer: a phase II trial

PURPOSE

To evaluate the patterns of recurrence when elective node irradiation was omitted in patients with limited disease small cell lung cancer (LD-SCLC).

METHODS

A prospective phase II study was undertaken in 27 patients with LD-SCLC without detectable distant metastases on CT scan. Chest radiotherapy to a dose of 45 Gy in 30 fractions in 3 weeks (1.5 Gy BID with 6 - 8 h interval) was delivered concurrently with carboplatin and etoposide chemotherapy. Chest radiation started after a mean time of 17.7 days +/- 9.7 days (SD) (range: 0-33 days) after the beginning of chemotherapy. Only the primary tumour and the positive nodal areas on the pre-treatment CT scan were irradiated. A total of five chemotherapy cycles were administered, followed by prophylactic cranial irradiation (PCI) in patients without disease progression. Isolated nodal failure was defined as recurrence in the regional nodes outside of the clinical target volume, in the absence of in-field failure.

RESULTS

After a median time of 18 months post-radiotherapy, 7 patients (26%, 95% CI 19.5-42.5%) developed a local recurrence. Three patients (crude rate 11%, 95% CI 2.4-29%), developed an isolated nodal failure, all of them in the ipsilateral supraclavicular fossa. The median actuarial overall survival was 21 months (95% CI 15.3-26.7), and the median actuarial progression free survival was 16 months (95% CI 6.5-25.5). Eight patients developed an acute, reversible grade 3 (CTC 3.0) radiation oesophagitis (30%, 95% CI 14-50%).

CONCLUSIONS

Because of the small sample size, no definitive conclusions can be drawn. However, the omission of elective nodal irradiation on the basis of CT scans in patients with LD-SCLC resulted in a higher than expected rate of isolated nodal failures in the ipsilateral supraclavicular fossa. The incidence of acute, reversible oesophagitis was in the same range as reported with elective nodal fields. The safety of selective nodal irradiation in NSCLC should not be extrapolated to patients with LD-SCLC until more data are available. In the mean time, elective nodal irradiation should only be omitted in clinical trials.

Selective mediastinal node irradiation based on FDG-PET scan data in patients with non–small-cell lung cancer: A prospective clinical study

PURPOSE

To evaluate the patterns of recurrence when selective mediastinal node irradiation based on FDG-PET scan data is used in patients with non-small-cell lung cancer (NSCLC).

METHODS AND MATERIALS

A prospective Phase I/II study was undertaken on 44 patients with NSCLC without detectable distant metastases on CT and FDG-PET scan, delivering either 61.2 Gy in 34 fractions over 23 days or 64.8 Gy in 36 fractions over 24 days (1.8 Gy b.i.d. with 8-h interval). Only the primary tumor and the positive mediastinal areas on the pretreatment FDG-PET scan were irradiated. Isolated nodal failure was defined as recurrence in the regional nodes outside of the clinical target volume, in the absence of in-field failure.

RESULTS

The CT and FDG-PET stage distribution was as follows: Stage I: 8 patients (18%) and 13 patients (29%); Stage II: 6 patients (14%) and 10 patients (23%); Stage IIIA: 15 patients (34%) and 7 patients (16%); Stage IIIB: 15 patients (34%) and 14 patients (32%), respectively. After a median follow-up time of 16 months (95% confidence interval [CI], 11-21 months) postradiotherapy, 11 patients (25%) developed a local recurrence. Only 1 patient (crude rate, 2.3%; upper bound of 95% CI, 10.3%), with a Stage II tumor on both CT and PET, developed an isolated nodal failure. The median actuarial overall survival was 21 months (95% CI, 14-28 months), and the median actuarial progression-free survival was 18 months (95% CI, 12-24 months).

CONCLUSIONS

Selective mediastinal node irradiation based on FDG-PET scan data in patients with NSCLC results in low isolated nodal failure rates. In the Phase I component of this trial, radiation dose escalation up to 64.8 Gy in 36 fractions over 24 days is feasible.

Detection of oncogenic mutations in the EGFR gene in lung adenocarcinoma with differential sensitivity to EGFR tyrosine kinase inhibitors

The complete sequencing of the human genome and the development of molecularly targeted cancer therapy have promoted efforts to identify systematically the genetic alterations in human cancer. By high-throughput sequencing of tyrosine kinase genes in human non-small-cell lung cancer, we identified somatic mutations in the kinase domain of the epidermal growth factor receptor tyrosine kinase gene (EGFR) that are correlated with clinical response to EGFR tyrosine kinase inhibitors (TKIs). We have shown that these mutant forms of EGFR induce oncogenic transformation in different cellular systems. Cells whose growth depends on EGFR with mutations in exons 19 and 21 are sensitive to EGFR-TKIs, whereas cells expressing insertion mutations in exon 20 or the T790M point mutant, found in tumor biopsies from patients that relapsed after an initial response to EGFR-TKIs, are resistant. Furthermore, by applying a novel, massively parallel sequencing technology, we have shown that clinically relevant oncogene mutations can be detected in clinical specimens with very low tumor content, thereby enabling optimal patient selection for mutation-directed therapy. In summary, by applying high-throughput genomic resequencing, we have identified a novel therapeutic target, mutant EGFR, in lung cancer and evaluated its role in predicting response to targeted therapy.