A
bstract
Effects of massive object’s spin on massive-massless 2 → 2 classical scattering is studied. Focus is set on the less-considered dimensionless expansion parameter
λ/b
, where
λ
is the ...massless particle’s wavelength and
b
is the impact parameter. Corrections in
λ/b
start to appear from
O
(
G
2
), with leading correction terms tied to the gravitational Faraday effect, which is a special case of the Lense-Thirring effect. We compute the eikonal phase up to
O
(
G
2
) and extract spin effect on the scattering angle and time delay up to 14th order in spin. The gravitational Faraday effect at linear order in spin
1
is reproduced by
λ/b
correction terms, which we compute to higher orders in spin. We find that the equivalence principle, or universality, holds up to NLO for general spinning bodies, i.e. away from geometric optics limit. Furthermore, in the black hole limit, we confirm the absence of particular spin structure observed
2
–
8
, along with the associated shift symmetry
7
, and argue that it holds to arbitrary spin order at
O
(
G
2
) in the massless probe limit.
In the last few decades, biological reconstruction techniques have improved greatly for treating high-grade osteosarcoma patients. To conserve the limb, and its function the affected tumor-bearing ...bones have been treated using liquid nitrogen and irradiation processes that enable the removal of entire tumors from the bone, and these treated autografts can be reconstructed for the patients. Here, we focus on the expressions of the growth factor family proteins from the untreated and treated autografts that play a crucial role in bone union, remodeling, and regeneration. In this proteomic study, we identify several important cytoskeletal, transcriptional, and growth factor family proteins that showed substantially low levels in untreated autografts. Interestingly, these protein expressions were elevated after treating the tumor-bearing bones using liquid nitrogen and irradiation. Therefore, from our preliminary findings, we chose to determine the expressions of BMP2, TGF-Beta, and FGFR proteins by the target proteomics approach. Using a newly recruited validation set, we successfully validate the expressions of the selected proteins. Furthermore, the increased growth factor protein expression after treatment with liquid nitrogen may contribute to bone regeneration healing, assist in faster recovery, and reduce local recurrence and metastatic spread in high-grade sarcoma patients.
We use the recently developed generalized double-copy construction to obtain an improved representation of the five-loop four-point integrand of N=8 supergravity whose leading ultraviolet behavior we ...analyze using state-of-the-art loop-integral expansion and reduction methods. We find that the five-loop critical dimension where ultraviolet divergences first occur is Dc=24/5, corresponding to a D8R4 counterterm. This ultraviolet behavior stands in contrast to the cases of four-dimensional N=4 supergravity at three loops and N=5 supergravity at four loops whose improved ultraviolet behavior demonstrates enhanced cancellations beyond implications from standard symmetry considerations. We express this Dc=24/5 divergence in terms of two relatively simple positive-definite integrals with vanishing external momenta, excluding any additional ultraviolet cancellations at this loop order. We note nontrivial relations between the integrals describing this leading ultraviolet behavior and integrals describing lower-loop behavior. This observation suggests not only a path towards greatly simplifying future calculations at higher loops, but may even allow us to directly investigate ultraviolet behavior in terms of simplified integrals, avoiding the construction of complete integrands.
Photo-responsive materials can convert light energy into mechanical energy, with great application potential in biomedicine, flexible electronic devices, and bionic systems. We combined reversible ...amide bonds, coordination site regulation, and coordination polymer (CP) self-assembly to synthesize two 1D photo-responsive CPs. Obvious photomechanical behavior was observed under UV irradiation. By combining the CPs with PVA, the mechanical stresses were amplified and macroscopic driving behavior was realized. In addition, two cyclobutane amide derivatives and a pair of cyclobutane carboxyl isomers were isolated through coordination bond destruction and amide bond hydrolysis. Therefore, photo-actuators and supramolecular synthesis in smart materials may serve as important clues.
Photo-responsive materials can convert light energy into mechanical energy, with great application potential in biomedicine, flexible electronic devices, and bionic systems.
Recent studies have indicated that cancer stem-like cells (CSCs) exhibit a high resistance to current therapeutic strategies, including photodynamic therapy (PDT), leading to the recurrence and ...progression of colorectal cancer (CRC). In cancer, autophagy acts as both a tumor suppressor and a tumor promoter. However, the role of autophagy in the resistance of CSCs to PDT has not been reported. In this study, CSCs were isolated from colorectal cancer cells using PROM1/CD133 (prominin 1) expression, which is a surface marker commonly found on stem cells of various tissues. We demonstrated that PpIX-mediated PDT induced the formation of autophagosomes in PROM1/CD133
+
cells, accompanied by the upregulation of autophagy-related proteins ATG3, ATG5, ATG7, and ATG12. The inhibition of PDT-induced autophagy by pharmacological inhibitors and silencing of the ATG5 gene substantially triggered apoptosis of PROM1/CD133
+
cells and decreased the ability of colonosphere formation in vitro and tumorigenicity in vivo. In conclusion, our results revealed a protective role played by autophagy against PDT in CSCs and indicated that targeting autophagy could be used to elevate the PDT sensitivity of CSCs. These findings would aid in the development of novel therapeutic approaches for CSC treatment.
In this work, a high thermoelectric figure of merit, zT of 1.9 at 740 K is achieved in Ge
Bi
Te crystals through the concurrent of Seebeck coefficient enhancement and thermal conductivity reduction ...with Bi dopants. The substitution of Bi for Ge not only compensates the superfluous hole carriers in pristine GeTe but also shifts the Fermi level (E
) to an eligible region. Experimentally, with moderate 6-10% Bi dopants, the carrier concentration is drastically decreased from 8.7 × 10
cm
to 3-5 × 10
cm
and the Seebeck coefficient is boosted three times to 75 μVK
. In the meantime, based on the density functional theory (DFT) calculation, the Fermi level E
starts to intersect with the pudding mold band at L point, where the band effective mass is enhanced. The enhanced Seebeck coefficient effectively compensates the decrease of electrical conductivity and thus successfully maintain the power factor as large as or even superior than that of the pristine GeTe. In addition, the Bi doping significantly reduces both thermal conductivities of carriers and lattices to an extremely low limit of 1.57 W m
K
at 740 K with 10% Bi dopants, which is an about 63% reduction as compared with that of pristine GeTe. The elevated figure of merit observed in Ge
Bi
Te specimens is therefore realized by synergistically optimizing the power factor and downgrading the thermal conductivity of alloying effect and lattice anharmonicity caused by Bi doping.
The effects and risks of endovascular thrombectomy 6 to 24 hours after stroke onset due to basilar-artery occlusion have not been extensively studied.
In a trial conducted over a 5-year period in ...China, we randomly assigned, in a 1:1 ratio, patients with basilar-artery stroke who presented between 6 to 24 hours after symptom onset to receive either medical therapy plus thrombectomy or medical therapy only (control). The original primary outcome, a score of 0 to 4 on the modified Rankin scale (range, 0 to 6, with a score of 0 indicating no disability, 4 moderately severe disability, and 6 death) at 90 days, was changed to a good functional status (a modified Rankin scale score of 0 to 3, with a score of 3 indicating moderate disability). Primary safety outcomes were symptomatic intracranial hemorrhage at 24 hours and 90-day mortality.
A total of 217 patients (110 in the thrombectomy group and 107 in the control group) were included in the analysis; randomization occurred at a median of 663 minutes after symptom onset. Enrollment was halted at a prespecified interim analysis because of the superiority of thrombectomy. Thrombolysis was used in 14% of the patients in the thrombectomy group and in 21% of those in the control group. A modified Rankin scale score of 0 to 3 (primary outcome) occurred in 51 patients (46%) in the thrombectomy group and in 26 (24%) in the control group (adjusted rate ratio, 1.81; 95% confidence interval CI, 1.26 to 2.60; P<0.001). The results for the original primary outcome of a modified Rankin scale score of 0 to 4 were 55% and 43%, respectively (adjusted rate ratio, 1.21; 95% CI, 0.95 to 1.54). Symptomatic intracranial hemorrhage occurred in 6 of 102 patients (6%) in the thrombectomy group and in 1 of 88 (1%) in the control group (risk ratio, 5.18; 95% CI, 0.64 to 42.18). Mortality at 90 days was 31% in the thrombectomy group and 42% in the control group (adjusted risk ratio, 0.75; 95% CI, 0.54 to 1.04). Procedural complications occurred in 11% of the patients who underwent thrombectomy.
Among patients with stroke due to basilar-artery occlusion who presented 6 to 24 hours after symptom onset, thrombectomy led to a higher percentage with good functional status at 90 days than medical therapy but was associated with procedural complications and more cerebral hemorrhages. (Funded by the Chinese National Ministry of Science and Technology; BAOCHE ClinicalTrials.gov number, NCT02737189.).
Immediately recycling the resected bone segment in a biologic limb salvage reconstruction is an option after wide resection of bone. Intraoperative extracorporeal irradiation and freezing are the two ...major tumor-killing techniques applied on the fresh tumor-bearing autografts. However, graft-derived tumor recurrence and complications are concerns affecting graft survival.
We therefore asked: (1) Is there a difference in the proportion of patients achieving union by 18 months after surgery between the groups with extracorporeal-irradiated autografts and frozen-treated autografts? (2) Is there any difference in the frequency of graft-related complications for patients receiving either an extracorporeal-irradiated or a frozen-treated autograft? (3) Is there a difference between the techniques in terms of graft-derived recurrence? (4) Are there differences in failure-free grafts, and limb and overall survivorship between autografts treated by extracorporeal irradiation or by freezing?
During the study period we treated a total of 333 patients with high-grade osteosarcoma. One hundred sixty-nine patients were excluded. Overall, 79 of the enrolled 164 patients received recycled autografts treated with extracorporeal irradiation whereas the other 85 received frozen-treated autografts. The mean followup was 82 ± 54 months for the extracorporeal irradiation group and 70 ± 25 months for the frozen autograft group, and one patient was lost to followup. Complications and graft failure (revision required for primary graft removal) were characterized by adapting the International Society of Limb Society (ISOLS) system modified for inclusion of biologic and expandable reconstruction. The primary study endpoints were the proportion of patients in each group who achieved radiographic union, and had an ISOLS grade of fair or good host graft fusion at 6, 9, 12, and 18 months after surgery. Five-year survival data for graft failure and limb amputation were analyzed by a cumulative incidence function regression model whereas the Kaplan-Meier function was used to test the 5-year overall survival rate between the two techniques.
With the numbers available, no differences were found in the accumulated proportion of patients achieving union between the groups at 6, 9, 12, and 18 months. Radiographic evaluation did not show differences in the average scores of compared criteria. However in the subchondral bone subcriterion, more patients receiving frozen-treated autografts had higher scores (p = 0.03). Complications leading to a second surgery were not different between extracorporeal irradiation and frozen autografts in aspects of soft tissue failure (Type 1B), nonunion (Type 2B), structural failure (Type 3A and Type 3B), or infection (Type 4A and Type 4B). No graft-originating tumor recurrence was found and there was no difference in Type 5A tumor progression originating from soft tissue in the groups (odds ratio, 0.8; 95% CI, 0.3-2.1; p = 0.7). Neither group showed a difference in the cumulative incidence for graft failure and limb amputation. Five-year overall survival rates were 83% and 84% (p = 0.69) for extracorporeal-irradiated and frozen autografts respectively. A decrease in survivorship was seen at 50 to 100 months after surgery for the extracorporeal irradiation group.
We segregated the ISOLS criteria evaluating the graft-mediated tumor progression into host- or graft-derived complications (Types 5B and 5C) in this study. With the available data, there was no difference in the incidence of tumor recurrence derived from irradiation- or frozen-treated autografts. Ongoing evaluations comparing 10-year survivorship for both groups will be helpful to elucidate the possible difference found after 100 months.
III, therapeutic study.
Background/Aims: Circular RNAs (circRNAs), a type of RNA that is widely expressed in human cells, have essential roles in the development and progression of cancer. CircRNAs contain microRNA (miRNA) ...binding sites and can function as miRNA sponges to regulate gene expression by removing the inhibitory effect of an miRNA on its target gene. Methods: We used the bioinformatics software TargetScan and miRanda to predict circRNA-miRNA and miRNAi-Mrna interactions. Rate of inhibiting of proliferation was measured using a WST-8 cell proliferation assay. Clone formation ability was assessed with a clone formation inhibition test. Cell invasion and migration capacity was evaluated by performing a Transwell assay. Relative gene expression was assessed using quantitative real-time polymerase chain reaction and relative protein expression levels were determined with western blotting. circRNA and miRNA interaction was confirmed by dual-luciferase reporter and RNA-pull down assays. Results: In the present study, the miRNA hsa-miR-21-5p was a target of circRNA-ACAP2, and T lymphoma invasion and metastasis protein 1 (Tiam1) was identified as a target gene of hsa-miR-21-5p. CircRNA-ACAP2 and Tiam1 were shown to be highly expressed in colon cancer tissue and colon cancer SW480 cells, but miR-21-5p was expressed at a low level. SW480 cell proliferation was suppressed when the expression of circRNA-ACAP2 and Tiam1 was decreased and the expression of miR-21-5p was increased in vivo and in vitro. SW480 cell migration and invasion were also inhibited under the same circumstance. The circRNA-ACAP2 interaction regulated the expression of miR-21-5p, and miR-21-5p regulated the expression of Tiam1. Down-regulation of circRNA-ACAP2 promoted miR-21-5p expression, which further suppressed the transcription and translation of Tiam1. Conclusion: The present study shows that the circRNA-ACAP2/hsa-miR-21-5p/Tiam1 regulatory feedback circuit could affect the proliferation, migration, and invasion of colon cancer SW480 cells. This was probably due to the fact that circRNA-ACAP2 could act as a miRNA sponge to regulate Tiam1 expression by removing the inhibitory effect of miR-21-5p on Tiam1 expression. The results from this study have revealed new insights into the pathogenicity of colon cancer and may provide novel therapeutic targets for the treatment of colon cancer.