Impaired Inhibitory Control in Recreational Cocaine Users

Chronic use of cocaine is associated with impairment in response inhibition but it is an open question whether and to which degree findings from chronic users generalize to the upcoming type of recreational users. This study compared the ability to inhibit and execute behavioral responses in adult recreational users and in a cocaine-free-matched sample controlled for age, race, gender distribution, level of intelligence, and alcohol consumption. Response inhibition and response execution were measured by a stop-signal paradigm. Results show that users and non users are comparable in terms of response execution but users need significantly more time to inhibit responses to stop-signals than non users. Interestingly, the magnitude of the inhibitory deficit was positively correlated with the individuals lifetime cocaine exposure suggesting that the magnitude of the impairment is proportional to the degree of cocaine consumed

Evaluating the Robustness of Question-Answering Models to Paraphrased Questions

Understanding questions expressed in natural language is a fundamental challenge studied under different applications such as question answering (QA). We explore whether recent state-of-the-art models are capable of recognizing two paraphrased questions using unsupervised learning. Firstly, we test QA models’ performance on an existing paraphrased dataset (Dev-Para). Secondly, we create a new paraphrased evaluation set (Para-SQuAD) containing multiple paraphrased question pairs from the SQuAD dataset. We describe qualitative investigations on these models and how they present paraphrased questions in continuous space. The results demonstrate that the paraphrased dataset confuses the QA models and decreases their performance. Visualizing the sentence embeddings of Para-SQuAD by the QA models suggests that all models, except BERT, struggle to recognize paraphrased questions effectively

Executive control deficits in substance-dependent individuals: A comparison of alcohol, cocaine, and methamphetamine and of men and women

Substance dependence is associated with executive function deficits, but the nature of these executive defects and the effect that different drugs and sex have on these defects have not been fully clarified. Therefore, we compared the performance of alcohol- (n = 33; 18 women), cocaine- (n = 27; 14 women), and methamphetamine-dependent individuals (n = 38; 25 women) with sex-matched healthy comparisons (n = 36; 17 women) on complex decision making as measured with the Iowa Gambling Task, working memory, cognitive flexibility, and response inhibition. Cocaine- and methamphetamine-dependent individuals were impaired on complex decision making, working memory, and cognitive flexibility, but not on response inhibition. The deficits in working memory and cognitive flexibility were milder than the decision-making deficits and did not change as a function of memory load or task switching. Interestingly, decision making was significantly more impaired in women addicted to cocaine or methamphetamine than in men addicted to these drugs. Together, these findings suggest that drug of choice and sex have different effects on executive functioning, which, if replicated, may help tailor intervention

Does oncological outcome differ between restorative and nonrestorative low anterior resection in patients with primary rectal cancer?

Aim: Nonrestorative low anterior resection (n-rLAR) (also known as low Hartmann’s) is performed for rectal cancer when a poor functional outcome is anticipated or there have been problems when constructing the anastomosis. Compared with restorative LAR (rLAR), little oncological outcome data are available for n-rLAR. The aim of this study was to compare oncological outcomes between rLAR and n-rLAR for primary rectal cancer. Method: This was a nationwide cross-sectional comparative study including all elective sphincter-saving LAR procedures for nonmetastatic primary rectal cancer performed in 2011 in 71 Dutch hospitals. Oncological outcomes of patients undergoing rLAR and n-rLAR were collected in 2015; the data were evaluated using Kaplan–Meier survival analysis and the results compared using log-rank testing. Uni- and multivariable Cox regression analysis was used to evaluate the association between the type of LAR and oncological outcome measures. Results: A total of 1197 patients were analysed, of whom 892 (75%) underwent rLAR and 305 (25%) underwent n-rLAR. The 3-year local recurrence (LR) rate was 3% after rLAR and 8% after n-rLAR (P < 0.001). The 3-year disease-free survival and overall survival rates were 77% (rLAR) vs 62% (n-rLAR) (P < 0.001) and 90% (rLAR) vs 75% (n-rLAR) (P < 0.001), respectively. In multivariable Cox analysis, n-rLAR was independently associated with a higher risk of LR (OR = 2.95) and worse overall survival (OR = 1.72). Conclusion: This nationwide study revealed that n-rLAR for rectal cancer was associated with poorer oncological outcome than r-LAR. This is probably a noncausal relationship, and might reflect technical difficulties during low pelvic dissection in a subset of those patients, with oncological implications

Treatment and survival of locally recurrent rectal cancer: A cross-sectional population study 15 years after the Dutch TME trial

Introduction: Optimized treatment of primary rectal cancer might have influenced treatment characteristics and outcome of locally recurrent rectal cancer (LRRC). Subgroup analysis of the Dutch TME trial showed that preoperative radiotherapy (PRT) for the primary tumour was an independent poor prognostic factor after diagnosis of LRRC. This cross-sectional population study aimed to evaluate treatment and overall survival (OS) of LRRC patients, stratified for prior preoperative radiotherapy (PRT) and intention of treatment of LRRC. Methods: All patients developing LRRC were selected from a collaborative Snapshot study on 2095 surgically treated rectal cancer patients from 71 Dutch hospitals in the year 2011. Cox proportional hazard analysis was performed to determine predictors for OS. Results: A total of 107 LRRC patients (5.1%) were included, of whom 88 (82%) underwent PRT for their primary tumour. LRRC was treated with initial curative intent in 31 patients (29%), with eventual resection in 20 patients (19%). Median OS was 22 and 8 months after curative and palliative intent treatment, respectively (p < 0.001). Initial CRM positivity and palliative intent treatment were associated with worse OS after LRRC, while prior PRT was not. Conclusions: This cross-sectional study revealed that rectal cancer patients, who underwent curative resection in the Netherlands in 2011 and subsequently developed local recurrence, were amenable for again curative intent treatment in 29%, with a corresponding median survival of 22 months. Prior PRT was not significantly associated with survival after diagnosis of LRRC

Prognostic importance of lymph node count and ratio in rectal cancer after neoadjuvant chemoradiotherapy: Results from a cross-sectional study

Background: The aim of this study was to determine the prognostic value of lymph node count (LNC) and lymph node ratio (LNR) in rectal cancer after neoadjuvant chemoradiotherapy (CRT). Methods: Patients who underwent neoadjuvant CRT and total mesorectal excision (TME) for Stage I–III rectal cancer were selected from a cross-sectional study including 71 Dutch centres. Primary outcome parameters were disease-free survival (DFS) and overall survival (OS). Prognostic significance of LNC and LNR (cut-off values 0.15, 0.20, 0.30) was tested for different (sub)groups. Results: From 2095 registered patients, 458 were included, of which 240 patients with LNC < 12 and 218 patients with LNC ≥ 12. LNC was not significantly associated with DFS (p = 0.35) and OS (p = 0.59). In univariable analysis, LNR was significantly associated with DFS and OS in the whole cohort and LNC subgroups, but not in multivariable analysis. Conclusions: LNC was not associated with long-term oncological outcome in rectal cancer patients treated with CRT, nor was LNR when corrected for N-stage. However, LNR might be used to identify subgroups of node-positive patients with a favourable outcome

The influence of hospital volume on long-term oncological outcome after rectal cancer surgery

Purpose: The association between hospital volume and outcome in rectal cancer surgery is still subject of debate. The purpose of this study was to assess the impact of hospital volume on outcomes of rectal cancer surgery in the Netherlands in 2011. Methods: In this collaborative research with a cross-sectional study design, patients who underwent rectal cancer resection in 71 Dutch hospitals in 2011 were included. Annual hospital volume was stratified as low (< 20), medium (20–50), and high (≥ 50). Results: Of 2095 patients, 258 patients (12.3%) were treated in 23 low-volume hospitals, 1329 (63.4%) in 40 medium-volume hospitals, and 508 (24.2%) in 8 high-volume hospitals. Median length of follow-up was 41 months. Clinical tumor stage, neoadjuvant therapy, extended resections, circumferential resection margin (CRM) positivity, and 30-day or in-hospital mortality did not differ significantly between volume groups. Significantly, more laparoscopic procedures were performed in low-volume hospitals, and more diverting stomas in high-volume hospitals. Three-year disease-free survival for low-, medium-, and high-volume hospitals was 75.0, 74.8, and 76.8% (p = 0.682). Corresponding 3-year overall survival rates were 75.9, 79.1, and 80.3% (p = 0.344). In multivariate analysis, hospital volume was not associated with long-term risk of mortality. Conclusions: No significant impact of hospital volume on rectal cancer surgery outcome could be observed among 71 Dutch hospitals after implementation of a national audit, with the majority of patients being treated at medium-volume hospitals