13 research outputs found
Coexistence of superconductivity with exotic ferromagnetic state in pressurized non-superconducting UTe
The discovery of superconductivity in heavy Fermion UTe, a candidate
topological and triplet-paired superconductor, has aroused widespread interest.
However, to date, superconductivity has only been reported in nonstoichiometric
crystals of UTe with a Te deficit. Here, we demonstrate that the
application of uniaxial pressure induces superconductivity in stoichiometric
UTe crystals. Measurements of resistivity, magnetoresistance and
susceptibility reveal that uniaxial pressure results in a suppression of the
Kondo coherent state seen at ambient pressure, leading to the emergence of
superconductivity initially at 1.5 GP, followed by the development of bulk
superconductivity at 4.8 GPa. The superconducting state coexists with an exotic
ferromagnetically ordered (FM) state that develops just below the onset
temperature of the superconducting transition. High-pressure synchrotron x-ray
diffraction measurements performed at 20 K indicate that no structural phase
transition occurs over the measured pressure range. Our results not only
demonstrate the coexistence of superconductivity with an exotic ferromagnetic
state in pressurized stoichiometric UTe, but also highlight a vital role of
Te deficiency in developing superconductivity at ambient pressures.Comment: 17 pages, 4 figure
Pressure-induced coevolution of transport properties and lattice stability in CaK(Fe1-xNix)4As4 (x= 0.04 and 0) superconductors with and without spin-vortex crystal state
Here we report the first investigation on correlation between the transport
properties and the corresponding stability of the lattice structure for
CaK(Fe1-xNix)4As4 (x=0.04 and 0), a new type of putative topological
superconductors, with and without a spin-vortex crystal (SVC) state in a wide
pressure range involving superconducting to non-superconducting transition and
the half- to full-collapse of tetragonal (h-cT and f-cT) phases, by the
complementary measurements of high-pressure resistance, Hall coefficient and
synchrotron X-ray diffraction. We identify the three critical pressures, P1
that is the turn-on critical pressure of the h-cT phase transition and it
coincides with the critical pressure for the sign change of Hall coefficient
from positive to negative, a manifestation of the Fermi surface reconstruction,
P2 that is the turn-off pressures of the h-cT phase transition, and P3 that is
the critical pressure of the f-cT phase transition. By comparing the
high-pressure results measured from the two kinds of samples, we find a
distinct left-shift of the P1 for the doped sample, at the pressure of which
its SVC state is fully suppressed, however the P2 and the P3 remain the same as
that of the undoped one. Our results not only provide a consistent
understanding on the results reported before, but also demonstrate the
importance of the Fe-As bonding in stabilizing the superconductivity of the
iron pnictide superconductors through the pressure window
BRAF Mutations in Advanced Cancers: Clinical Characteristics and Outcomes
BACKGROUND: Oncogenic BRAF mutations have been found in diverse malignancies and activate RAF/MEK/ERK signaling, a critical pathway of tumorigenesis. We examined the clinical characteristics and outcomes of patients with mutant (mut) BRAF advanced cancer referred to phase 1 clinic. METHODS: We reviewed the records of 80 consecutive patients with mutBRAF advanced malignancies and 149 with wild-type (wt) BRAF (matched by tumor type) referred to the Clinical Center for Targeted Therapy and analyzed their outcome. RESULTS: Of 80 patients with mutBRAF advanced cancer, 56 had melanoma, 10 colorectal, 11 papillary thyroid, 2 ovarian and 1 esophageal cancer. Mutations in codon 600 were found in 77 patients (62, V600E; 13, V600K; 1, V600R; 1, unreported). Multivariate analysis showed less soft tissue (Odds ratio (OR) = 0.39, 95%CI: 0.20-0.77, P = 0.007), lung (OR = 0.38, 95%CI: 0.19-0.73, p = 0.004) and retroperitoneal metastases (OR = 0.34, 95%CI: 0.13-0.86, p = 0.024) and more brain metastases (OR = 2.05, 95%CI: 1.02-4.11, P = 0.043) in patients with mutBRAF versus wtBRAF. Comparing to the corresponding wtBRAF, mutBRAF melanoma patients had insignificant trend to longer median survival from diagnosis (131 vs. 78 months, p = 0.14), while mutBRAF colorectal cancer patients had an insignificant trend to shorter median survival from diagnosis (48 vs. 53 months, p = 0.22). In melanoma, V600K mutations in comparison to other BRAF mutations were associated with more frequent brain (75% vs. 36.3%, p = 0.02) and lung metastases (91.6% vs. 47.7%, p = 0.007), and shorter time from diagnosis to metastasis and to death (19 vs. 53 months, p = 0.046 and 78 vs. 322 months, p = 0.024 respectively). Treatment with RAF/MEK targeting agents (Hazard ratio (HR) = 0.16, 95%CI: 0.03-0.89, p = 0.037) and any decrease in tumor size after referral (HR = 0.07, 95%CI: 0.015-0.35, p = 0.001) correlated with longer survival in mutBRAF patients. CONCLUSIONS: BRAF appears to be a druggable mutation that also defines subgroups of patients with phenotypic overlap, albeit with differences that correlate with histology or site of mutation
The breakdown of both strange metal and superconducting states at a pressure-induced quantum critical point in iron-pnictide superconductors
Abstract Here we report the first observation of the concurrent breakdown of the strange metal (SM) normal state and superconductivity at a pressure-induced quantum critical point in Ca10(Pt4As8)((Fe0.97Pt0.03)2As2)5 superconductor. We find that, upon suppressing the superconducting state, the power exponent (α) changes from 1 to 2, and the slope of the temperature-linear resistivity per FeAs layer (A □) gradually diminishes. At a critical pressure, A □ and superconducting transition temperature (T c ) go to zero concurrently, where a quantum phase transition from a superconducting state with a SM normal state to a non-superconducting Fermi liquid state occurs. Scaling analysis reveals that the change of A □ with T c obeys the relation of T c ~ (A □)0.5, similar to what is seen in other chemically doped unconventional superconductors. These results suggest that there is a simple but powerful organizational principle of connecting the SM normal state with the high-T c superconductivity
Traditional Herbal Medicine-Derived Sulforaphene LFS-01 Reverses Colitis in Mice by Selectively Altering the Gut Microbiota and Promoting Intestinal Gamma-Delta T Cells
Sulforaphene (LFS-01) is a natural compound derived from traditional herbal medicine. Here, we show that oral administration of LFS-01 is able to dramatically alter the skewed gut microbiota and reverse colitis in model mice associated with an increase of intestinal γδT cells. Through 16S rDNA sequencing, we showed that LFS-01 can selectively suppress enteric pathogens such as Escherichia–Shigella and Helicobacter whereas the protective strains including Lactobacillus and Lachnospiraceae were significantly expanded after LFS-01 treatment. Interestingly, we demonstrated that LFS-01 administration can significantly promote the IL-17+γδT cells in model mice in response to the expanded Lactobacillus. We verified that the intracellular components of Lactobacillus can stimulate the growth of IL-17+γδT cells upon preincubation. The increased IL-17A after LFS-01 treatment in turn recovers the disrupted occludin subcellular location and protects the epithelial barrier in the colon of model mice. Remarkably, LFS-01 does not show apparent toxicity to animals and we demonstrated that LFS-01 also exerts strong protective effects in TNBS-induced colitis rats. Therefore, LFS-01 holds great promise for the treatment of inflammatory bowel disease (IBD) and warrants translation for use in clinical trials. Our work provided a new avenue for the treatment of IBD based on the strategy of harnessing intestinal symbiosis
Cysteine Deprivation Targets Ovarian Clear Cell Carcinoma Via Oxidative Stress and Iron-Sulfur Cluster Biogenesis Deficit
10.1089/ars.2019.7850Antioxidants and Redox Signaling33171191-120
DataSheet1_A novel LUAD prognosis prediction model based on immune checkpoint-related lncRNAs.xlsx
Lung adenocarcinoma (LUAD) is a malignant disease with an extremely poor prognosis, and there is currently a lack of clinical methods for early diagnosis and precise treatment and management. With the deepening of tumor research, more and more attention has been paid to the role of immune checkpoints (ICP) and long non-coding RNAs (lncRNAs) regulation in tumor development. Therefore, this study downloaded LUAD patient data from the TCGA database, and finally screened 14 key ICP-related lncRNAs based on ICP-related genes using univariate/multivariate COX regression analysis and LASSO regression analysis to construct a risk prediction model and corresponding nomogram. After multi-dimensional testing of the model, the model showed good prognostic prediction ability. In addition, to further elucidate how ICP plays a role in LUAD, we jointly analyzed the immune microenvironmental changes in LAUD patients and performed a functional enrichment analysis. Furthermore, to enhance the clinical significance of this study, we performed a sensitivity analysis of common antitumor drugs. All the above works aim to point to new directions for the treatment of LUAD.</p