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CTGrepeat expansion (CTGexp) is associated with aberrant alternate splicing that contributes to cardiac dysfunction in myotonic dystrophy type 1 (DM1). Excision of thisCTGexprepeat using CRISPR-Cas resulted in the disappearance of punctate ribonuclear foci in cardiomyocyte-like cells derived from DM1-induced pluripotent stem cells (iPSCs). This was associated with correction of the underlying spliceopathy as determined byRNA sequencingand alternate splicing analysis. Certain genes were of particular interest due to their role in cardiac development, maturation, and function (TPM4,CYP2J2,DMD,MBNL3,CACNA1H,ROCK2,ACTB) or their association with splicing (SMN2,GCFC2,MBNL3). Moreover, while comparing isogenic CRISPR-Cas9-corrected versus non-corrected DM1 cardiomyocytes, a prominent difference in the splicing pattern for a number of candidate genes was apparent pertaining to genes that are associated with cardiac function (TNNT,TNNT2,TTN,TPM1,SYNE1,CACNA1A,MTMR1,NEBL,TPM1),cellular signaling(NCOR2,CLIP1,LRRFIP2,CLASP1,CAMK2G), and other DM1-related genes (i.e.,NUMA1,MBNL2,LDB3) in addition to the disease-causingDMPKgene itself. Subsequent validation using a selected gene subset, includingMBNL1,MBNL2,INSR,ADD3, andCRTC2, further confirmed correction of the spliceopathy followingCTGexprepeat excision. To our knowledge, the present study provides the first comprehensive unbiased transcriptome-wide analysis of the differential splicing landscape in DM1 patient-derived cardiac cells after excision of theCTGexprepeat using CRISPR-Cas9, showing reversal of the abnormal cardiac spliceopathy in DM1.

Purpose Megavoltage radiotherapy to irregular superficial targets is challenging due to the skin sparing effect. We developed a three-dimensional bolus (3DB) program to assess the clinical impact on dosimetric and patient outcomes. Materials and Methods Planar commercial bolus (PCB) and 3DB density, clarity, and net bolus effect were rigorously evaluated prior to clinical implementation. After IRB approval, patients with cutaneous or locally advanced malignancies deemed to require bolus for radiotherapy treatment were treated with custom 3DB. Results The mean density of 3DB and PCB was of 1.07 g/cm 3 and 1.12 g/cm3, respectively. 3DB optic clarity was superior versus PCB at any material thickness. Phantom measurements of superficial dose with 3DB and PCB showed excellent bolus effect for both materials. 3DB reduced air gaps compared with PCB - particularly in irregular areas such as the ear, nose, and orbit. A dosimetric comparison of 3DB and PCB plans showed equivalent superficial homogeneity for 3DB and PCB (3DB median HI 1.249, range 1.111–1.300 and PCB median HI 1.165, range 1.094–1.279), but better conformity with 3DB (3DB median CI 0.993, range 0.962–0.993) versus PCB (PCB median CI 0.977, range 0.601–0.991). Patient dose measurements using 3DB confirm the delivered superficial dose was within 1% of the intended prescription (95% CI 97–102%; P = 0.11). Conclusions 3DB improves radiotherapy plan conformity, reduces air gap volume in irregular superficial areas which could affect superficial dose delivery, and provides excellent dose coverage to irregular superficial targets.

Management of head and neck cancer in the elderly patient is particularly challenging given the high morbidity associated with treatment. Surgery, radiotherapy, and chemotherapy have all been demonstrated as effective in older patients; however, older patients are more susceptible to treatment-induced toxicity, which can limit the survival benefits of certain interventions. This susceptibility is better associated with the presence of multiple comorbidities and decreasing functional status than with age alone. Screening tools allow for risk stratification, treatment deintensification, and even treatment avoidance in patients who are deemed at high-risk of being harmed by standard therapy.

Objectives Compare length of stay, flap failure rate, medical and surgical complications and cost when patients undergoing head and neck free flap reconstruction are monitored in an intensive care unit (ICU) versus a specialty ward unit postoperatively. Materials and methods A prospective, non-inferiority, randomized controlled trial was conducted from 7/22/2016 to 9/12/2018 at a single institution. Patients were randomized to the ICU or specialty ward unit. Flap check protocols were identical between the groups. Perioperative and postoperative outcome variables were assessed and compared. Results 131 patients were enrolled in the study and 118 ultimately underwent head and neck free flap reconstruction. 57 were randomized to the ICU and 61 to the specialty ward unit. There were no significant differences between the ICU and specialty ward unit groups with regard to demographic variables including age, gender, co-morbidities, tobacco or alcohol use, prior chemotherapy or radiation therapy treatment. There were no significant differences in perioperative variables including need for transfusion, tracheostomy, ischemia time, blood loss, fluid administration or post-operative antibiotic use. There was no significant difference in the primary outcome variable, length of stay. There were no significant differences in the number of the medical or surgical complications, flap failure rate, or hospital costs. Conclusion In this prospective, randomized controlled trial, head and neck free-flap patients cared for on a specialty ward in the immediate post-operative period had equivalent outcomes to those cared for in the ICU.

a b s t r a c t Essential design criteria for successful drying of granular particles in a conical continuous centrifugal filter are developed in a dimensionless fashion. Four criteria are considered: minimum flow thickness (to ensure sliding bulk flow rather than particulate flow), desaturation position, output dryness and basket failure. The criteria are based on idealised physical models of the machine operation and are written explicitly as functions of the basket size lout, spin velocity ˝ and input flow rate of powder Qp. The separation of sucrose crystals from liquid molasses is taken as a case study and the successful regime of potential operating points (lout, ˝) is plotted for a wide range of selected values of flow rate Qp. Analytical expressions are given for minimum and maximum values of the three independent parameters (lout, ˝, Qp) as a function of the slurry and basket properties. The viable operating regime for a conical centrifugal filter is thereby obtained as a function of the slurry and basket properties. © 2012 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

A one-dimensional analytical model is developed for the steady state, axisymmetric, slender flow of saturated powder in a rotating perforated cone. Both the powder and the fluid spin with the cone with negligible slip in the hoop direction. They migrate up the wall of the cone along a generator under centrifugal force, which also forces the fluid out of the cone through the powder layer and the porous wall. The flow thus evolves from an over-saturated paste at inlet into a nearly dry powder at outlet. The powder is treated as a Mohr–Coulomb granular solid of constant void fraction and permeability. The shear traction at the wall is assumed to be velocity and pressure dependent. The fluid is treated as Newtonian viscous. The model provides the position of the colour line (the transition from over- to under-saturation) and the flow velocity and thickness profiles over the cone. Surface tension effects are assumed negligible compared to the centrifugal acceleration. Two alternative conditions are considered for the flow structure at inlet: fully settled powder at inlet, and progressive settling of an initially homogeneous slurry. The position of the colour line is found to be similar for these two cases over a wide range of operating conditions. Dominant dimensionless groups are identified which control the position of the colour line in a continuous conical centrifuge. Experimental observations of centrifuges used in the sugar industry provide preliminary validation of the model.

Expansion of repeated sequences in non-coding regions of different genes causes a number of inherited diseases including myotonic dystrophies, Huntington disease-like 2, Fragile X tremor/ataxia syndrome and spinocerebellar ataxia 8, 10, 12, 31. Involvement of an RNA gain-of-function mechanism in pathological case has been described and studied in-depth in myotonic dystrophy type 1 (DM1). This inherited neuromuscular disorder is caused by a (CTG)n >50 expansion in the 3' non-coding region of the dystrophia myotonica-protein kinase (DMPK) gene. Expanded CUG transcripts (CUGexp-RNAs) are sequestered in the nucleus within small aggregates and interfere with the regulatory splicing activities of MBNL1 and CELF1 RNA-binding proteins, leading to the misregulation of the alternative splicing of several transcripts. Despite the relevance of aberrant splicing events in this complex pathology, the CUGexp-RNAs trans-dominant effects alter other splicing-independent processes that may also contribute to DM1 pathogenesis. This review will focus on toxic RNA gain-of-function as a pathologic mechanism for DM1 and other repeat expansion disorders.

A CTG repeat amplification is responsible for the dominantly inherited neuromuscular disorder, myotonic dystrophy type 1 (DM1), which is characterized by progressive muscle wasting and weakness. The expanded (CTG)n tract not only alters the myogenic differentiation of the DM1 muscle precursor cells but also reduces their proliferative capacity. In this report, we show that these muscle precursor cells containing large CTG expansion sequences have not exhausted their proliferative capacity, but have entered into premature senescence. We demonstrate that an abnormal accumulation of p16 is responsible for this defect because the abolition of p16 activity overcomes early growth arrest and restores an extended proliferative capacity. Our results suggest that the accelerated telomere shortening measured in DM1 cells does not contribute to the aberrant induction of p16. We propose that a cellular stress related to the amplified CTG repeat promotes premature senescence mediated by a p16-dependent pathway in DM1 muscle precursor cells. This mechanism is responsible for the reduced proliferative capacity of the DM1 muscle precursor cells and could participate in both the impaired regeneration and atrophy observed in the DM1 muscles containing large CTG expansions.

Purpose/Objective(s): To perform a retrospective analysis of variables influencing survival in a cohort of patients with acinic cell carcinoma (AciCC). Materials/Methods: A retrospective database analysis was performed using the United States National Cancer Institute’s Surveillance, Epidemiology and End Results (SEER) registry. We obtained demographic, staging, pathologic and treatment data pertaining to patients diagnosed with AciCC between 1973-2009. Univariate and multivariate analyses of overall and disease specific survival (DSS) were performed to compare survival trends associated with various clinical and pathological parameters. Results: We identified 2,061 patients from the SEER registry who were diagnosed with AciCC between 1973-2009, with demographics similar to recently published cohorts. Tumor size, nodal status, distant metastases and histologic grade were all significant predictors of survival up to 20 years post-treatment. Patients who received surgery alone for treatment had the highest 20-year DSS (92.4 %), with significantly lower DSS for patients treated with surgery and radiation (71.9%) or radiation alone (62.3 %). These survival differences remained significant when stratifying patients for age, gender, nodal status, stage and histologic grade. In addition, hazard ratios showed significantly improved prognosis with surgery only compared with surgery and radiation or radiation alone. Conclusions: To our knowledge, this study represents the largest cohort of AciCC survival according to treatment modality. Our results suggest the addition of radiation to surgical resection does not provide significant benefit to survival in patients with salivary AciCC. Author Disclosure: V.L. Biron: None. D. Gerry: None. E. Lentsch: None. A. Bewley: None.