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1.
Gestational trophoblastic neoplasia (GTN) patients are treated according to the eight-variable International Federation of Gynaecology and Obstetrics (FIGO) scoring system, that aims to predict first-line single-agent chemotherapy resistance. FIGO is imperfect with one-third of low-risk patients developing disease resistance to first-line single-agent chemotherapy. We aimed to generate simplified models that improve upon FIGO. Logistic regression (LR) and multilayer perceptron (MLP) modelling (n = 4191) generated six models (M1-6). M1, all eight FIGO variables (scored data); M2, all eight FIGO variables (scored and raw data); M3, nonimaging variables (scored data); M4, nonimaging variables (scored and raw data); M5, imaging variables (scored data); and M6, pretreatment hCG (raw data) + imaging variables (scored data). Performance was compared to FIGO using true and false positive rates, positive and negative predictive values, diagnostic odds ratio, receiver operating characteristic (ROC) curves, Bland-Altman calibration plots, decision curve analysis and contingency tables. M1-6 were calibrated and outperformed FIGO on true positive rate and positive predictive value. Using LR and MLP, M1, M2 and M4 generated small improvements to the ROC curve and decision curve analysis. M3, M5 and M6 matched FIGO or performed less well. Compared to FIGO, most (excluding LR M4 and MLP M5) had significant discordance in patient classification (McNemar's test P < .05); 55-112 undertreated, 46-206 overtreated. Statistical modelling yielded only small gains over FIGO performance, arising through recategorisation of treatment-resistant patients, with a significant proportion of under/overtreatment as the available data have been used a priori to allocate primary chemotherapy. Streamlining FIGO should now be the focus.  相似文献   
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Introduction

Despite the risk of morbidity and mortality associated with autologous hematopoietic cell transplantation (ASCT), there are no clear guidelines as to how to screen for these risks. This study sought to determine the utility of pulmonary function tests (PFTs) prior to ASCT on predicting posttransplant clinical outcomes.

Patients and Methods

Patients undergoing ASCT between 2010 and 2012 at the Ottawa Hospital (n = 172) were reviewed. PFT results prior to ASCT were retrieved. The primary outcomes were incidence of intensive care unit (ICU) admission, Seattle Criteria for pulmonary toxicities, and transplant-related mortality (TRM).

Results

PFTs were performed for 91 (53%) patients prior to ASCT. There were more smokers in the PFT cohort than the non-PFT cohort (41.8% vs. 19.8%, respectively; P < .0001). Pulmonary toxicity as measured by the Seattle Criteria did not correlate with PFT results (normal vs. abnormal, 8.1% and 6.1%, respectively; P = 1.00). There were no differences in incidence of ICU admission by PFT result (normal vs. abnormal, 2.7% vs. 8.2%, respectively; P = .61) and no difference in TRM by PFT result (normal vs. abnormal, 0% vs. 2.0%, respectively; P = 1.00).

Conclusion

Despite testing patients deemed higher risk for pulmonary toxicity, abnormal PFTs did not predict for an increased risk of pulmonary toxicity, ICU admission, or TRM at our center.  相似文献   
10.
Adverse energy states exert a potent suppressive influence on the reproductive axis by inhibiting the pulsatile release of gonadotrophin‐releasing hormone and luteinising hormone. One potential mechanism underlying this involves the metabolic‐sensing pro‐opiomelanocortin and agouti‐related peptide/neuropeptide Y (AgRP/NPY) neuronal populations directly controlling the activity of the arcuate nucleus kisspeptin neurones comprising the gonadotrophin‐releasing hormone pulse generator. Using acute brain slice electrophysiology and calcium imaging approaches in Kiss1‐GFP and Kiss1‐GCaMP6 mice, we investigated whether NPY and α‐melanocyte‐stimulating hormone provide a direct modulatory influence on the activity of arcuate kisspeptin neurones in the adult mouse. NPY was found to exert a potent suppressive influence upon the neurokinin B‐evoked firing of approximately one‐half of arcuate kisspeptin neurones in both sexes. This effect was blocked partially by the NPY1R antagonist BIBO 3304, whereas the NPY5R antagonist L152,804 was ineffective. NPY also suppressed the neurokinin B‐evoked increase in intracellular calcium levels in the presence of tetrodotoxin and amino acid receptor antagonists, indicating that the inhibitory effects of NPY are direct on kisspeptin neurones. By contrast, no effects of α‐melanocyte‐stimulating hormone were found on the excitability of arcuate kisspeptin neurones. These studies provide further evidence supporting the hypothesis that AgRP/NPY neurones link energy status and luteinising hormone pulsatility by demonstrating that NPY has a direct suppressive influence upon the activity of a subpopulation of arcuate kisspeptin neurones.  相似文献   
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