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TP53 is the most frequently mutated gene in head and neck squamous cell carcinoma (HNSCC). Patients with HPV-negative TP53 mutant HNSCC have the worst prognosis, necessitating additional agents for treatment. Since mutant p53 causes sustained activation of the PI3K/AKT/mTOR signaling pathway, we investigated the effect of rapalogs RAD001 and CCI-779 on HPV-negative mutTP53 HNSCC cell lines and xenografts. Rapalogs significantly reduced cell viability and colony formation. Interestingly, rapalogs-induced autophagy with no effect on apoptosis. Pretreatment with autophagy inhibitors, 3-methyladenine (3-MA) and ULK-101 rescued the cell viability by inhibiting rapalog-induced autophagy, suggesting that both RAD001 and CCI-779 induce non-apoptotic autophagy-dependent cell death (ADCD). Moreover, rapalogs upregulated the levels of ULK1 and pULK1 S555 with concomitant downregulation of the mTORC1 pathway. However, pretreatment of cells with rapalogs prevented the ULK-101-mediated inhibition of ULK1 to sustained autophagy, suggesting that rapalogs induce ADCD through the activation of ULK1. To further translate our in vitro studies, we investigated the effect of RAD001 in HPV-negative mutTP53 (HN31 and FaDu) tumor cell xenograft model in nude mice. Mice treated with RAD001 exhibited a significant tumor volume reduction without induction of apoptosis, and with a concomitant increase in autophagy. Further, treatment with RAD001 was associated with a considerable increase in pULK1 S555 and ULK1 levels through the inhibition of mTORC1. 3-MA reversed the effect of RAD001 on FaDu tumor growth suggesting that RAD001 promotes ACDC in HPV-negative mutTP53 xenograft. This is the first report demonstrating that rapalogs promote non-apoptotic ADCD in HPV-negative mutTP53 HNSCC via the ULK1 pathway. Further studies are required to establish the promising role of rapalogs in preventing the regrowth of HPV-negative mutTP53 HNSCC.  相似文献   
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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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BackgroundThe purpose of this study is to evaluate the effect of body mass index (BMI) on discharge to a postacute care (PAC) facility following elective total shoulder arthroplasty (TSA).MethodsThe National Surgical Quality Improvement Program database was queried to identify adult patients (>18 years old) who underwent inpatient TSA for primary osteoarthritis between 2005 and 2018. Hemiarthroplasty, revision TSA, trauma indications, and outpatient procedures were excluded. Patient and perioperative data were identified. Univariate analysis and multivariate logistic regression were used to assess the relationship between BMI and discharge to PAC facilities.ResultsA total of 10,198 patients with a primary TSA were identified. The majority (93%) of patients were discharged home vs. 7% to PAC facilities. Patients discharged to PAC had significantly higher mean BMI (P = .006). After controlling for demographic and comorbid factors, BMI was the only modifiable risk factor that was independently associated with an increased risk of discharge to a PAC. For every increase in BMI point, there was an increased risk of discharge to a PAC by 2.9% (odds ratio [OR] 1.029, confidence interval [CI] 1.016-1.041, P < .001). Additional covariates associated with PAC discharge were older age (OR 1.113, CI 1.099-1.127, P < .001), female gender (OR 3.037, CI 2.489-3.705, P < .001), and dependent functional status (OR 8.322, CI 5.544-12.492, P < .001).ConclusionMost patients undergoing TSA were discharged home following surgery. While age, sex, and functional status also affect disposition, elevated BMI is the only modifiable risk factor that independently predicts PAC discharge. Consideration of patient BMI prior to elective TSA may greatly improve discharge planning and management of patient expectations.  相似文献   
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ABSTRACT

Background

The link of acute pancreatitis (AP) with Incretin based therapies (IBTs) in type 2 diabetes has existed since United States Food and Drug Administration alert in 2010. This issue still remains unresolved due to conflicting results among studies.  相似文献   
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Background

Multiple myeloma (MM) is a hematologic malignancy of plasma cell origin. MM primarily affects bone marrow, but extramedullary sites can also be involved. Myelomatous pleural effusion (MPE) is an atypical and rare complication of MM. We aimed to systematically study the incidence and clinicopathologic profile of patients with MPE in a real-world setting.

Patients and Methods

In this retrospective study, 415 consecutive patients with MM managed at a tertiary care center in North India during a study period of January 1, 2010 to December 31, 2015 were evaluated for MPE. The patients with MPE were analyzed for their clinical profile, diagnosis, treatment, and outcomes.

Results

Of these 415 patients, 11 (2.65%) patients had MPE. The median age of the study population was 50 years with male preponderance. The majority of these patients had immunoglobin (Ig)G Kappa disease. All patients had higher than International Staging System stage I disease. MPE was a presenting feature at MM diagnosis in 45.45% (n = 5) of the patients, whereas the rest developed MPE during follow-up. MPE presented predominantly (81.8%) as a unilateral effusion. Concurrent extramedullary involvement at other site was seen in 45.45% (n = 5), with 3 (27%) patients having concurrent myelomatous ascites. Six of these were managed aggressively, whereas 5 patients opted for palliation. The outcomes were dismal (90.9% mortality), with a median survival of 2.47 months.

Conclusion

MPE is a rare entity, and positive outcomes of therapy remain low with dismal prognosis.  相似文献   
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Sirtuin‐1 and ‐3 (SIRT1 and SIRT3) are important nicotinamide adenine dinucleotide (NAD+)‐dependent deacetylases known to regulate a variety of cellular functions. Studies have shown that SIRT1 and SIRT3 were overexpressed in human melanoma cells and tissues and their inhibition resulted in a significant antiproliferative response in human melanoma cells and antitumor response in a mouse xenograft model of melanoma. In this study, we determined the antiproliferative efficacy of a newly identified dual small molecule inhibitor of SIRT1 and SIRT3, 4′‐bromo‐resveratrol (4′‐BR), in human melanoma cell lines (G361, SK‐MEL‐28, and SK‐MEL‐2). Our data demonstrate that 4′‐BR treatment of melanoma cells resulted in (a) decrease in proliferation and clonogenic survival; (b) induction of apoptosis accompanied by a decrease in procaspase‐3, procaspase‐8, and increase in the cleavage of caspase‐3 and poly (ADP‐ribose) polymerase (PARP); (c) marked downregulation of proliferating cell nuclear antigen (PCNA); and (d) inhibition of melanoma cell migration. Further, 4′‐BR caused a G0/G1 phase arrest of melanoma cells that was accompanied by an increase in WAF‐1/P21 and decrease in Cyclin D1/Cyclin‐dependent kinase 6 protein levels. Furthermore, we found that 4′‐BR causes a decrease in lactate production, glucose uptake, and NAD+/NADH ratio. These responses were accompanied by downregulation in lactate dehydrogenase A and glucose transporter 1 in melanoma cells. Collectively, our data suggest that dual inhibition of SIRT1 and SIRT3 using 4′‐BR imparted antiproliferative effects in melanoma cells through a metabolic reprogramming and affecting the cell cycle and apoptosis signaling. Therefore, concomitant pharmacological inhibition of SIRT1 and SIRT3 needs further investigation for melanoma management.  相似文献   
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