ABSTRACT
Progressive increases in the precision of the Hubble-constant measurement via Cepheid-calibrated Type Ia supernovae (SNe Ia) have shown a discrepancy of ∼4.4σ with the current value inferred ...from Planck satellite measurements of the cosmic microwave background radiation and the standard $\Lambda $cold dark matter (ΛCDM) cosmological model. This disagreement does not appear to be due to known systematic errors and may therefore be hinting at new fundamental physics. Although all of the current techniques have their own merits, further improvement in constraining the Hubble constant requires the development of as many independent methods as possible. In this work, we use SNe II as standardisable candles to obtain an independent measurement of the Hubble constant. Using seven SNe II with host-galaxy distances measured from Cepheid variables or the tip of the red giant branch, we derive H$_0= 75.8^{+5.2}_{-4.9}$ km s−1 Mpc−1 (statistical errors only). Our value favours that obtained from the conventional distance ladder (Cepheids + SNe Ia) and exhibits a difference of 8.4 km s−1 Mpc−1 from the Planck + ΛCDM value. Adding an estimate of the systematic errors (2.8 km s−1 Mpc−1) changes the ∼1.7σ discrepancy with Planck +ΛCDM to ∼1.4σ. Including the systematic errors and performing a bootstrap simulation, we confirm that the local H0 value exceeds the value from the early Universe with a confidence level of 95 per cent. As in this work, we only exchange SNe II for SNe Ia to measure extragalactic distances, we demonstrate that there is no evidence that SNe Ia are the source of the H0 tension.
In this work, BVRI light curves of 55 Type II supernovae (SNe II) from the Lick Observatory Supernova Search programme obtained with the Katzman Automatic Imaging Telescope and the 1 m Nickel ...telescope from 2006 to 2018 are presented. Additionally, more than 150 spectra gathered with the 3 m Shane telescope are published. We conduct an analyse of the peak absolute magnitudes, decline rates, and time durations of different phases of the light and colour curves. Typically, our light curves are sampled with a median cadence of 5.5 d for a total of 5093 photometric points. In average, V-band plateau declines with a rate of 1.29 mag (100 d)(exp −1), which is consistent with previously published samples. For each band, the plateau slope correlates with the plateau length and the absolute peak magnitude: SNe II with steeper decline have shorter plateau duration and are brighter. A time-evolution analysis of spectral lines in term of velocities and pseudo-equivalent widths is also presented in this paper. Our spectroscopic sample ranges between 1 and 200 d post-explosion and has a median ejecta expansion velocity at 50 d post-explosion of 6500 km s(exp −1) (H α line) and a standard dispersion of 2000 km s(exp −1). Nebular spectra are in good agreement with theoretical models using a progenitor star having a mass <16M⨀. All the data are available to the community and will help to understand SN II diversity better, and therefore to improve their utility as cosmological distance indicators.
ABSTRACT
The most stringent local measurement of the Hubble–Lemaître constant from Cepheid-calibrated Type Ia supernovae (SNe Ia) differs from the value inferred via the cosmic microwave background ...radiation (Planck+ΛCDM) by ∼5σ. This so-called Hubble tension has been confirmed by other independent methods, and thus does not appear to be a possible consequence of systematic errors. Here, we continue upon our prior work of using Type II supernovae to provide another, largely independent method to measure the Hubble–Lemaître constant. From 13 SNe II with geometric, Cepheid, or tip of the red giant branch (TRGB) host-galaxy distance measurements, we derive H$_0= 75.4^{+3.8}_{-3.7}$ km s−1 Mpc−1 (statistical errors only), consistent with the local measurement but in disagreement by ∼2.0σ with the Planck+ΛCDM value. Using only Cepheids (N = 7), we find H$_0 = 77.6^{+5.2}_{-4.8}$ km s−1 Mpc−1, while using only TRGB (N = 5), we derive H$_0 = 73.1^{+5.7}_{-5.3}$ km s−1 Mpc−1. Via 13 variants of our data set, we derive a systematic uncertainty estimate of 1.5 km s−1 Mpc−1. The median value derived from these variants differs by just 0.3 km s−1 Mpc−1 from that produced by our fiducial model. Because we only replace SNe Ia with SNe II – and we do not find statistically significant difference between the Cepheid and TRGB H0 measurements – our work reveals no indication that SNe Ia or Cepheids could be the sources of the ‘H0 tension.’ We caution, however, that our conclusions rest upon a modest calibrator sample; as this sample grows in the future, our results should be verified.
Background
The current standard of care for locally advanced esophageal and gastroesophageal junction (GEJ) adenocarcinoma includes neoadjuvant chemoradiation and surgery. The optimal treatment for ...clinical T2N0M0 (cT2N0) disease is debated. This study aims to determine the optimal treatment in these patients.
Methods
The National Cancer Database was used to identify patients who underwent surgery for cT2N0 esophageal and GEJ adenocarcinoma from 2004 to 2017. Patients were grouped into surgery-alone, neoadjuvant therapy (NAT), and adjuvant therapy (AT) groups. Subgroups of high-risk patients (tumor ≥ 3 cm, poor differentiation, or lymphovascular invasion) and patients upstaged after upfront surgery were identified. Kaplan–Meier method and Cox proportional hazard ratios were used to compare overall survival.
Results
Of 2160 patients included, 957 (44.3%) underwent surgery-alone, 821 (38.0%) underwent NAT and surgery, and 382 (17.7%) underwent surgery and AT. One thousand six hundred nineteen (75.0%) patients had high-risk features. Six hundred fourteen (45.9%) patients were upstaged after upfront surgery. In the overall cohort, AT was associated with improved survival compared to NAT (HR 0.618,
p
< 0.001) and surgery-alone (HR 0.699,
p
< 0.001). There was no difference in survival between NAT and surgery-alone (HR 1.132,
p
= 0.112). Similar results were observed in high-risk patients. Patients upstaged after upfront surgery who received AT had improved survival compared to those initially treated with NAT (HR 0.613,
p
< 0.001).
Conclusion
This analysis suggests that cT2N0 esophageal and GEJ adenocarcinomas may not benefit from the intensive multimodality therapy utilized in locally advanced disease. Selective use of AT for patients who are upstaged pathologically, or have high-risk features, is associated with improved outcomes.
Background
Clinical and pathologic staging determine treatment of pancreatic cancer. Clinical stage has been shown to underestimate final pathologic stage in pancreatic cancer, resulting in ...upstaging.
Methods
National Cancer Database was used to identify clinical stage I pancreatic adenocarcinoma. Univariate, multivariable logistic regression, and Cox proportional hazard ratio were used to determine differences between upstaged and stage concordant patients.
Results
Upstaging was seen in 80.2% of patients. Factors found to be significantly associated with upstaging included pancreatic head tumors (OR 2.56), high‐grade histology (OR 1.74), elevated Ca 19‐9 (OR 2.09), and clinical stage T2 (OR 1.99). Upstaging was associated with a 45% increased risk of mortality compared to stage concordant disease (HR 1.44, p < .001).
Conclusion
A majority of clinical stage I pancreatic cancer is upstaged after resection. Factors including tumor location, grade, Ca 19‐9, and tumor size can help identify those at high risk for upstaging.
Tears play an essential role in maintaining corneal and conjunctival integrity by providing a tightly regulated, optimal extracellular environment critical to its numerous functions, which include ...anti-microbial defense, wound healing and inflammatory responses such as allergies. Elevated levels of inflammatory cytokines have been reported in tears from various ocular disease states. Characterization of tear cytokines has been limited by the small volume (microliter amounts) attainable. This limitation was addressed with the newly developed Becton Dickinson Cytometric Bead Array (CBA), which combines the principles of the “sandwich” immunoassay with the capability of flow cytometry for simultaneous measurement of the characteristics of multiple particles. This technique allows determination of six human cytokine (IFNγ, TNFα, IL-2, IL-4, IL-5, IL-10) concentrations simultaneously in a single tear sample. Tears were collected from the inferior fornix of non-allergic (
n=7) and allergic (
n=9) donors. Each tear sample or cytokine standard was incubated with a mixture of capture Ab-bead reagent and detector Ab-phycoerythrin (PE) reagent, and analyzed using flow cytometry. All six cytokines were detectable in both non-allergic and allergic tears. Tears from allergic donors contained significantly less IL-10 (
p=0.035), and had significant increases in the ratios of TNFα/IFNγ, IL-5/IFNγ and IL-5/IL-10 (
p=0.0008, 0.0124 and 0.011, respectively). The small volume required (5–10 μl/test) by the Cytometric Bead Array allows measurement of all six cytokines from a single collection of tears. This decreases collection time, minimizing the confounding effect of stimulation on cytokine concentration in tears, as well as allowing calculation of cytokine ratios.
Jaundice in the setting of periampullary neoplasms is often treated with biliary stenting. Level 1 data demonstrated an increase in perioperative complications after pancreaticoduodenectomy in ...patients undergoing stent placement. However, the impact of this data on practice patterns in the US remains unknown.
The National Surgical Quality Improvement Program (NSQIP) Pancreatectomy Targeted Participant Use Data File was used to identify patients from 2014 to 2017 undergoing pancreatoduodenectomy. Chi-square test and multivariable logistic regression were used to compare outcomes between those with biliary stent and those without.
Of the 5524 patients, 3321 (60.1%) had biliary stent placement. The stent group was older, had a higher ASA class, and had preoperative weight loss compared to the group without biliary stenting (all p < 0.05). When adjusting for demographic and operative characteristics, the non-stent group had lower associated overall complications and postoperative infections. There was no significant difference in mortality and pancreatic fistula rate between groups.
Preoperative biliary stenting is still common prior to pancreaticoduodenectomy. With a trend toward increased utilization of neoadjuvant chemotherapy, stenting will likely remain a common practice. Recognition of increased rates of complications associated with stent placement allows for appropriate risk-benefit analysis.
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