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Outcomes and prognostic factors in parotid gland malignancies: A 10-year single center experience.
Objectives:To describe a 10-year single center experience with parotid gland malignancies and to determine factors affecting outcomes. Study Design:Retrospective review. Methods:The institutional cancer registry was used to identify patients treated surgically for malignancies of the parotid gland between January 2005 and December 2014. Clinical and pathologic data were collected retrospectively from patient charts and analyzed for their association with overall survival (OS) and disease-free survival (DFS). Results:Two hundred patients were identified. Mean age at surgery was 57.8 years, and mean follow-up time was 52 months. One hundred two patients underwent total parotidectomy, while 77 underwent superficial parotidectomy, and 21 underwent deep lobe resection. Seventy patients (35%) required facial nerve (FN) sacrifice. Acinic cell carcinoma was the most common histologic type (22%), followed by mucoepidermoid carcinoma (21.5%) and adenoid cystic carcinoma (12.5%). Twenty-nine patients (14.5%) experienced recurrences, with mean time to recurrence of 23.6 months (range: 1-82 months). Five- and 10-year OS were 81% and 73%, respectively. Five- and 10-year DFS were 80% and 73%, respectively. In univariate analyses, age > 60, histologic type, positive margins, high grade, T-stage, node positivity, perineural invasion, and FN involvement were predictors of OS and DFS. In the multivariate analysis, histology, positive margins, node positivity, and FN involvement were independent predictors of OS and DFS. Conclusions:Our single-center experience of 200 patients suggests that histology, positive margins, node positivity, and FN involvement are independently associated with outcomes in parotid malignancies. Level of Evidence:4
Relationship between volume status and blood pressure during chronic hemodialysis
Relationship between volume status and blood pressure during chronic hemodialysis.BackgroundThe relationship between volume status and blood pressure (BP) in chronic hemodialysis (HD) patients remains incompletely understood. Specifically, the effect of interdialytic fluid accumulation (or intradialytic fluid removal) on BP is controversial.MethodsWe determined the association of the intradialytic decrease in body weight (as an indicator of interdialytic fluid gain) and the intradialytic decrease in plasma volume (as an indicator of postdialysis volume status) with predialysis and postdialysis BP in a cross-sectional analysis of a subset of patients (N = 468) from the Hemodialysis (HEMO) Study. Fifty-five percent of patients were female, 62% were black, 43% were diabetic and 72% were prescribed antihypertensive medications. Dry weight was defined as the postdialysis body weight below which the patient developed symptomatic hypotension or muscle cramps in the absence of edema. The intradialytic decrease in plasma volume was calculated from predialysis and postdialysis total plasma protein concentrations and was expressed as a percentage of the plasma volume at the beginning of HD.ResultsPredialysis systolic and diastolic BP values were 153.1 ± 24.7 (mean ± SD) and 81.7 ± 14.8mm Hg, respectively; postdialysis systolic and diastolic BP values were 136.6 ± 22.7 and 73.9 ± 13.6mm Hg, respectively. As a result of HD, body weight was reduced by 3.1 ± 1.3kg and plasma volume was contracted by 10.1 ± 9.5%. Multiple linear regression analyses showed that eachkg reduction in body weight during HD was associated with a 2.95mm Hg (P = 0.004) and a 1.65mm Hg (P = NS) higher predialysis and postdialysis systolic BP, respectively. In contrast, each 5% greater contraction of plasma volume during HD was associated with a 1.50mm Hg (P = 0.026) and a 2.56mm Hg (P < 0.001) lower predialysis and postdialysis systolic BP, respectively. The effects of intradialytic decreases in body weight and plasma volume were greater on systolic BP than on diastolic BP.ConclusionsHD treatment generally reduces BP, and these reductions in BP are associated with intradialytic decreases in both body weight and plasma volume. The absolute predialysis and postdialysis BP levels are influenced differently by acute intradialytic decreases in body weight and acute intradialytic decreases in plasma volume; these parameters provide different information regarding volume status and may be dissociated from each other. Therefore, evaluation of volume status in chronic HD patients requires, at minimum, assessments of both interdialytic fluid accumulation (or the intradialytic decrease in body weight) and postdialysis volume overload
Electronic interactions in Dirac fluids visualized by nano-terahertz spacetime mapping
Ultraclean graphene at charge neutrality hosts a quantum critical Dirac fluid
of interacting electrons and holes. Interactions profoundly affect the charge
dynamics of graphene, which is encoded in the properties of its collective
modes: surface plasmon polaritons (SPPs). The group velocity and lifetime of
SPPs have a direct correspondence with the reactive and dissipative parts of
the tera-Hertz (THz) conductivity of the Dirac fluid. We succeeded in tracking
the propagation of SPPs over sub-micron distances at femto-second (fs) time
scales. Our experiments uncovered prominent departures from the predictions of
the conventional Fermi-liquid theory. The deviations are particularly strong
when the densities of electrons and holes are approximately equal. Our imaging
methodology can be used to probe the electromagnetics of quantum materials
other than graphene in order to provide fs-scale diagnostics under
near-equilibrium conditions
Functional Identification of Api5 as a Suppressor of E2F-Dependent Apoptosis In Vivo
Retinoblastoma protein and E2-promoter binding factor (E2F) family members are important regulators of G1-S phase progression. Deregulated E2F also sensitizes cells to apoptosis, but this aspect of E2F function is poorly understood. Studies of E2F-induced apoptosis have mostly been carried out in tissue culture cells, and the analysis of the factors that are important for this process has been restricted to the testing of a few candidate genes. Using Drosophila as a model system, we have generated tools that allow genetic modifiers of E2F-dependent apoptosis to be identified in vivo and developed assays that allow effects on E2F-induced apoptosis to be studied in cultured cells. Genetic interactions show that dE2F1-dependent apoptosis in vivo involves dArk/Apaf1 apoptosome-dependent activation of both initiator and effector caspases and is sensitive to levels of Drosophila inhibitor of apoptosis-1 (dIAP1). Using these approaches, we report the surprising finding that apoptosis inhibitor-5/antiapoptosis clone-11 (Api5/Aac11) is a critical determinant of dE2F1-induced apoptosis in vivo and in vitro. This functional interaction occurs in multiple tissues, is specific to E2F-induced apoptosis, and is conserved from flies to humans. Interestingly, Api5/Aac11 acts downstream of E2F and suppresses E2F-dependent apoptosis without generally blocking E2F-dependent transcription. Api5/Aac11 expression is often upregulated in tumor cells, particularly in metastatic cells. We find that depletion of Api5 is tumor cell lethal. The strong genetic interaction between E2F and Api5/Aac11 suggests that elevated levels of Api5 may be selected during tumorigenesis to allow cells with deregulated E2F activity to survive under suboptimal conditions. Therefore, inhibition of Api5 function might offer a possible mechanism for antitumor exploitation
The Genomic and Evolutionary Landscapes of Anaplastic Thyroid Carcinoma
Anaplastic thyroid carcinoma is arguably the most lethal human malignancy. It often co-occurs with differentiated thyroid cancers, yet the molecular origins of its aggressivity are unknown. We sequenced tumor DNA from 329 regions of thyroid cancer, including 213 from patients with primary anaplastic thyroid carcinomas. We also whole genome sequenced 9 patients using multi-region sequencing of both differentiated and anaplastic thyroid cancer components. Using these data, we demonstrate thatanaplastic thyroid carcinomas have a higher burden of mutations than other thyroid cancers, with distinct mutational signatures and molecular subtypes. Further, different cancer driver genes are mutated in anaplastic and differentiated thyroid carcinomas, even those arising in a single patient. Finally, we unambiguously demonstrate that anaplastic thyroid carcinomas share a genomic origin with co-occurring differentiated carcinomas and emerge from a common malignant field through acquisition of characteristic clonal driver mutations
Gravitational Test beyond the First Post-Newtonian Order with the Shadow of the M87 Black Hole
The 2017 Event Horizon Telescope (EHT) observations of the central source in M87 have led to the first measurement of the size of a black-hole shadow. This observation offers a new and clean gravitational test of the black-hole metric in the strong-field regime. We show analytically that spacetimes that deviate from the Kerr metric but satisfy weak-field tests can lead to large deviations in the predicted black-hole shadows that are inconsistent with even the current EHT measurements. We use numerical calculations of regular, parametric, non-Kerr metrics to identify the common characteristic among these different parametrizations that control the predicted shadow size. We show that the shadow-size measurements place significant constraints on deviation parameters that control the second post-Newtonian and higher orders of each metric and are, therefore, inaccessible to weak-field tests. The new constraints are complementary to those imposed by observations of gravitational waves from stellar-mass sources
Monitoring the Morphology of M87* in 2009–2017 with the Event Horizon Telescope
The Event Horizon Telescope (EHT) has recently delivered the first resolved images of M87*, the supermassive black hole in the center of the M87 galaxy. These images were produced using 230 GHz observations performed in 2017 April. Additional observations are required to investigate the persistence of the primary image feature—a ring with azimuthal brightness asymmetry—and to quantify the image variability on event horizon scales. To address this need, we analyze M87* data collected with prototype EHT arrays in 2009, 2011, 2012, and 2013. While these observations do not contain enough information to produce images, they are sufficient to constrain simple geometric models. We develop a modeling approach based on the framework utilized for the 2017 EHT data analysis and validate our procedures using synthetic data. Applying the same approach to the observational data sets, we find the M87* morphology in 2009–2017 to be consistent with a persistent asymmetric ring of ~40 μas diameter. The position angle of the peak intensity varies in time. In particular, we find a significant difference between the position angle measured in 2013 and 2017. These variations are in broad agreement with predictions of a subset of general relativistic magnetohydrodynamic simulations. We show that quantifying the variability across multiple observational epochs has the potential to constrain the physical properties of the source, such as the accretion state or the black hole spin
Association of Variants in the SPTLC1 Gene With Juvenile Amyotrophic Lateral Sclerosis
Importance: Juvenile amyotrophic lateral sclerosis (ALS) is a rare form of ALS characterized by age of symptom onset less than 25 years and a variable presentation.Objective: To identify the genetic variants associated with juvenile ALS.Design, Setting, and Participants: In this multicenter family-based genetic study, trio whole-exome sequencing was performed to identify the disease-associated gene in a case series of unrelated patients diagnosed with juvenile ALS and severe growth retardation. The patients and their family members were enrolled at academic hospitals and a government research facility between March 1, 2016, and March 13, 2020, and were observed until October 1, 2020. Whole-exome sequencing was also performed in a series of patients with juvenile ALS. A total of 66 patients with juvenile ALS and 6258 adult patients with ALS participated in the study. Patients were selected for the study based on their diagnosis, and all eligible participants were enrolled in the study. None of the participants had a family history of neurological disorders, suggesting de novo variants as the underlying genetic mechanism.Main Outcomes and Measures: De novo variants present only in the index case and not in unaffected family members.Results: Trio whole-exome sequencing was performed in 3 patients diagnosed with juvenile ALS and their parents. An additional 63 patients with juvenile ALS and 6258 adult patients with ALS were subsequently screened for variants in the SPTLC1 gene. De novo variants in SPTLC1 (p.Ala20Ser in 2 patients and p.Ser331Tyr in 1 patient) were identified in 3 unrelated patients diagnosed with juvenile ALS and failure to thrive. A fourth variant (p.Leu39del) was identified in a patient with juvenile ALS where parental DNA was unavailable. Variants in this gene have been previously shown to be associated with autosomal-dominant hereditary sensory autonomic neuropathy, type 1A, by disrupting an essential enzyme complex in the sphingolipid synthesis pathway.Conclusions and Relevance: These data broaden the phenotype associated with SPTLC1 and suggest that patients presenting with juvenile ALS should be screened for variants in this gene.</p
Dependence of atmospheric muon flux on seawater depth measured with the first KM3NeT detection units: The KM3NeT Collaboration
KM3NeT is a research infrastructure located in the Mediterranean Sea, that will consist of two deep-sea Cherenkov neutrino detectors. With one detector (ARCA), the KM3NeT Collaboration aims at identifying and studying TeV–PeV astrophysical neutrino sources. With the other detector (ORCA), the neutrino mass ordering will be determined by studying GeV-scale atmospheric neutrino oscillations. The first KM3NeT detection units were deployed at the Italian and French sites between 2015 and 2017. In this paper, a description of the detector is presented, together with a summary of the procedures used to calibrate the detector in-situ. Finally, the measurement of the atmospheric muon flux between 2232–3386 m seawater depth is obtained
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