A highly distorted ultraelastic chemically complex Elinvar alloy.

The development of high-performance ultraelastic metals with superb strength, a large elastic strain limit and temperature-insensitive elastic modulus (Elinvar effect) are important for various industrial applications, from actuators and medical devices to high-precision instruments1,2. The elastic strain limit of bulk crystalline metals is usually less than 1 per cent, owing to dislocation easy gliding. Shape memory alloys3-including gum metals4,5 and strain glass alloys6,7-may attain an elastic strain limit up to several per cent, although this is the result of pseudo-elasticity and is accompanied by large energy dissipation3. Recently, chemically complex alloys, such as 'high-entropy' alloys8, have attracted tremendous research interest owing to their promising properties9-15. In this work we report on a chemically complex alloy with a large atomic size misfit usually unaffordable in conventional alloys. The alloy exhibits a high elastic strain limit (approximately 2 per cent) and a very low internal friction (less than 2 × 10-4) at room temperature. More interestingly, this alloy exhibits an extraordinary Elinvar effect, maintaining near-constant elastic modulus between room temperature and 627 degrees Celsius (900 kelvin), which is, to our knowledge, unmatched by the existing alloys hitherto reported.

Discovery of New Isotopes

Using the fusion-evaporation reaction ^{106}Cd(^{58}Ni,4n)^{160}Os and the gas-filled recoil separator SHANS, two new isotopes _{76}^{160}Os and _{74}^{156}W have been identified. The α decay of ^{160}Os, measured with an α-particle energy of 7080(26) keV and a half-life of 201_{-37}^{+58} µs, is assigned to originate from the ground state. The daughter nucleus ^{156}W is a ß^{+} emitter with a half-life of 291_{-61}^{+86} ms. The newly measured α-decay data allow us to derive α-decay reduced widths (δ^{2}) for the N=84 isotones up to osmium (Z=76), which are found to decrease with increasing atomic number above Z=68. The reduction of δ^{2} is interpreted as evidence for the strengthening of the N=82 shell closure toward the proton drip line, supported by the increase of the neutron-shell gaps predicted in theoretical models.

[Pathogenic investigation of human respiratory syncytial virus infection in kindergarten children in Tongzhou District, Beijing City in 2023].

The study focused on individuals with influenza-like symptoms (fever, cough, sore throat, runny nose, and other respiratory symptoms) in three kindergartens in Tongzhou District, Beijing City, in April 2023. Nasopharyngeal swab specimens were collected, and real-time fluorescent quantitative PCR was used to detect common respiratory pathogens in the collected specimens. Positive specimens were subjected to sequencing analysis of the highly variable region of human respiratory syncytial virus (HRSV) G protein, homology analysis and phylogenetic tree analysis. A total of 25 fever cases were collected from 3 kindergartens, aged 3-8 years old, with an age M (Q1, Q3) of 4 (3.5, 5) years old. Ten confirmed cases of HRSV positive were screened and detected using the fluorescent quantitative PCR method, with a total detection rate of 40% (10/25). Typing identification and sequencing analysis confirmed that the main epidemic type was HRSV subtype B, which was highly homologous and closely related to previous epidemic strains in the region. Through pathogen investigation and analysis, it was preliminarily determined that this epidemic was dominated by HRSV subtype B.

[Comparison of mid-to-long term outcomes between mitral valve repair and biological valve replacement in patients over 60 with rheumatic mitral valve disease based on a propensity score matching study].

Objective: To compare and discuss the mid-to-long-term outcomes of mitral valve repair (MVP) versus biological mitral valve replacement (bMVR) in patients over 60 years old with rheumatic mitral valve disease. Methods: This is a retrospective cohort study. A total of 765 patients aged 60 years and older, diagnosed with rheumatic mitral valve disease and who underwent MVP or bMVR at Beijing Anzhen Hospital from January 2010 to January 2023, were retrospectively included. Among them, 186 were male and 579 were female, with an age of (66.1±4.5) years (range: 60 to 82 years). Patients were divided into two groups based on the surgical method: the mitral valve repair group (MVP group, n=256) and the bioprosthetic mitral valve replacement group (bMVR group, n=509). A 1∶1 propensity score matching was performed using a caliper value of 0.2 based on preoperative data. Paired sample t-tests, χ² tests, or Fisher's exact tests were used for intergroup comparisons. Kaplan-Meier method was employed to plot survival curves and valve-related reoperation rate curves for both groups before and after matching, and Log-rank tests were used to compare the mid-to long-term survival rates and valve-related reoperation rates between the two groups. Results: A total of 765 patients who completed follow-up were ultimately included, with a follow-up period (M(IQR)) of 5.1(5.0) years (range: 1.0 to 12.9 years). After matching, each group consisted of 256 patients. The incidence of early postoperative atrial fibrillation (39.1% vs. 49.2%, χ2=4.95, P=0.026) and early mortality rates (2.0% vs. 6.2%, χ2=4.97, P=0.026) were lower in the MVP group. Unadjusted Kaplan-Meier analysis showed significantly higher 5-year and 10-year survival rates for the MVP group (92.54% vs. 83.02%, 86.22% vs. 70.19%, Log-rank P=0.001). After adjustment with propensity scores, the Kaplan-Meier analysis still indicated higher 5-year and 10-year survival rates in the MVP group compared to the bMVR group (92.54% vs. 85.89%, 86.22% vs. 74.83%, Log-rank P=0.024). There were no significant differences in the rates of valve-related reoperation between the two groups before and after matching (5-year and 10-year reoperation rates pre-matching: 1.75% vs. 0.57%, 5.39% vs. 7.54%, Log-rank P=0.207; post-matching: 1.75% vs. 0%, 5.39% vs. 9.27%, Log-rank P=0.157). Conclusion: For patients over 60 with rheumatic mitral valve disease, mitral valve repair offers better mid-to-long-term survival compared to biological valve replacement.

[Resistant hypertension and the risk of major adverse cardiac and cerebrovascular events in outpatients].

Objective: To investigate the prevalence and associated risk of cardiovascular event of resistant hypertension in treated outpatients. Methods: This study was a nationwide multi-center prospective cohort study. The participants were treated outpatients enrolled in the China Nationwide Ambulatory and Home Blood Pressure Registry study of 42 hospitals in 19 provinces across the country from August 2009 to October 2017. Apparent resistant hypertension was defined as uncontrolled office blood pressure (≥140/90 mmHg, 1 mmHg=0.133 kPa) in spite of the use of three antihypertensive drugs or controlled office blood pressure (<140/90 mmHg) with four antihypertensive drugs or more. Subjects diagnosed with uncontrolled office blood pressure were further subdivided as pseudo-resistant hypertension and true resistant hypertension based on 24 h ambulatory blood pressure monitoring. The primary endpoint was fatal and non-fatal cardiovascular and cerebrovascular events, which was a composite endpoint consisting of cardiovascular and cerebrovascular death, ischemic and hemorrhagic stroke, myocardial infarction, coronary artery revascularization, unstable angina, heart failure, and coronary artery stenosis≥50% confirmed by coronary angiography. Secondary outcomes included fatal and non-fatal stroke or cardiac events. Patients with controlled office blood pressure after taking only 1 or 2 antihypertensive drugs were included as control. Kaplan-Meier survival curves, log-rank test, and Cox proportional risk model were used to evaluate the risk of apparent refractory hypertension in relation to cardiovascular and cerebrovascular prognosis. Results: A total of 2 782 treated hypertensive patients, aged (58.1±12.3) years were enrolled, including 1 403 (50.4%) men. The prevalence of apparent and true resistant hypertension was 15.1% (420/2 782) and 10.5% (293/2 782), respectively. Among patients with apparent resistant hypertension, during a median of 5 years follow-up, the cumulative incidence rate was 28.2, 11.2 and 19.1 per 1 000 person-years for fatal and non-fatal cardiovascular events (n=58), stroke (n=24) and cardiac events (n=40), respectively. The Kaplan-Meier curve and log-rank test showed that those patients with true resistant hypertension, had the highest cumulative incidence rate of fatal and non-fatal cardiovascular events, stroke, and cardiac events. Multivariable Cox regression analyses showed that true resistant hypertension was associated with a significantly higher risk of fatal and non-fatal cardiovascular events (HR=1.73, 95%CI 1.17-2.56, P=0.006) and stroke (HR=2.81, 95%CI 1.53-5.17, P=0.001). Conclusion: Resistant hypertension, especially true resistant hypertension, is associated with a higher risk of fatal and non-fatal cardiac and cerebrovascular events.

Crystallization mechanism of the Pt50Au50 alloy with grain boundary segregation during the solidification process.

The crystalline mechanism of the Pt50Au50 alloy with grain boundary (GB) segregation during the rapid solidification process is investigated using molecular dynamics simulations. The cluster evolution and phase transformation processes during the GB segregation are analyzed by means of the energy temperature (E-T) curve, the pair distribution function (g(r)) curves, common neighborhood analysis (CNA), cluster-type index method (CTIM) and three-dimensional visualizing analyses. It is found that the GB segregation phenomenon of the Pt50Au50 alloy comes from various solidification temperatures of Pt- and Au-centered clusters. Four critical temperatures T1 (1153 K), T2 (1073 K), T3 (853 K) and T4 (753 K) are discovered during the liquid-solid transition, corresponding to the supercooled liquid, Pt-centered atom nucleation, Pt-centered cluster growth, Au-centered atom nucleation and grain growth process, respectively, which is observably different to the solidification process of other alloys. The Pt atoms begin to gather together in the high-temperature liquid before the liquid-solid transition. It is also found that the CTIM proposed by us would provide an effective tool to investigate the GB segregation process.

[Pathological features and clinicopathological significance of TERT promoter mutation in breast fibroepithelial tumors without definite diagnosis].

Objective: To investigate the pathological features and the clinicopathological significance of TERT detection in those tumors that were difficult to diagnosis. Methods: A total of 93 cases of fibroepithelial tumors without definite diagnosis were collected from the Affiliated Hospital of Qigndao University between 2013 and 2021. The clinical details such as patients' age and tumor size were collected. All slides were re-reviewed and the pathologic parameters, including stromal cellularity, stromal cell atypia, stromal cell mitoses, and stromal overgrowth were re-interpreted. Sanger sequencing was used to detect TERT promoter status, and immunohistochemistry was performed to detect TERT protein expression. The relationship between TERT promoter mutation as well as protein expression levels and the clinicopathological parameters were also analyzed. Results: The patients' ages ranged from 30 to 71 years (mean of 46 years); the tumor size ranged from 1.2 to 8.0 cm (mean 3.8 cm). These tumors showed the following morphologic features: leafy structures in the background of fibroadenoma, or moderately to severely abundant stromal cells. The interpretations of tumor border status were ambiguous in some cases. The incidence of TERT promoter mutation was high in patients of age≥50 years, tumor size≥4 cm, and stromal overgrowth at ×4 or ×10 objective, and these clinicopathologic features were in favor of diagnosis of phyllodes tumors. TERT protein expression levels was not associated with the above clinicopathologic parameters and its promoter mutation status. Conclusions: The diagnostic difficulty for the breast fibroepithelial tumors is due to the difficulty in recognition of the leafy structures or in those cases with abundant stromal cells. A comprehensive evaluation combined with morphologic characteristics and molecular parameters such as TERT promoter may be helpful for the correct diagnosis and better evaluating recurrence risk.

[Significance of TERT promoter mutation in differential diagnosis of non-invasive inverted urothelial lesions of bladder].

Objective: To investigate the gene mutation of telomerase reverse transcriptase (TERT) promoter in inverted urothelial lesions of the bladder and its significance in differential diagnosis. Methods: From March 2016 to February 2022, a total of 32 patients with inverted urothelial lesions diagnosed in Department of Pathology at Qingdao Chengyang People's Hospital and 24 patients at the Affiliated Hospital of Qingdao University were collected, including 7 cases of florid glandular cystitis, 13 cases of inverted urothelial papilloma, 8 cases of inverted urothelial neoplasm with low malignant potential, 17 cases of low-grade non-invasive inverted urothelial carcinoma, 5 cases of high-grade non-invasive inverted urothelial carcinoma, and 6 cases of nested subtype of urothelial carcinoma were retrospectively analyzed for their clinical data and histopathological features. TERT promoter mutations were analyzed by Sanger sequencing in all the cases. Results: No mutations in the TERT promoter were found in the florid glandular cystitis and inverted urothelial papilloma. The mutation rates of the TERT promoter in inverted urothelial neoplasm with low malignant potential, low grade non-invasive inverter urothelial carcinoma, high grade non-invasive inverted urothelial carcinoma and nested subtype urothelial carcinoma were 1/8, 8/17, 2/5 and 6/6, respectively. There was no significant difference in the mutation rate of TERT promoter among inverted urothelial neoplasm with low malignant potential, low-grade non-invasive inverted urothelial carcinoma, and high-grade non-invasive inverted urothelial carcinoma (P>0.05). All 6 cases of nested subtype of urothelial carcinoma were found to harbor the mutation, which was significantly different from inverted urothelial neoplasm with low malignant potential and non-invasive inverted urothelial carcinoma (P<0.05). In terms of mutation pattern, 13/17 of TERT promoter mutations were C228T, 4/17 were C250T. Conclusions: The morphology combined with TERT promoter mutation detection is helpful for the differential diagnosis of bladder non-invasive inverted urothelial lesions.

Observation of a Strongly Isospin-Mixed Doublet in

ß decay of proton-rich nuclei plays an important role in exploring isospin mixing. The ß decay of ^{26}P at the proton drip line is studied using double-sided silicon strip detectors operating in conjunction with high-purity germanium detectors. The T=2 isobaric analog state (IAS) at 13 055 keV and two new high-lying states at 13 380 and 11 912 keV in ^{26}Si are unambiguously identified through ß-delayed two-proton emission (ß2p). Angular correlations of two protons emitted from ^{26}Si excited states populated by ^{26}P ß decay are measured, which suggests that the two protons are emitted mainly sequentially. We report the first observation of a strongly isospin-mixed doublet that deexcites mainly via two-proton decay. The isospin mixing matrix element between the ^{26}Si IAS and the nearby 13 380-keV state is determined to be 130(21) keV, and this result represents the strongest mixing, highest excitation energy, and largest level spacing of a doublet ever observed in ß-decay experiments.

Probing

The isomer depletion of ^{93m}Mo was recently reported [Chiara et al., Nature (London) 554, 216 (2018)NATUAS0028-083610.1038/nature25483] as the first direct observation of nuclear excitation by electron capture (NEEC). However, the measured excitation probability of 1.0(3)% is far beyond the theoretical expectation. In order to understand the inconsistency between theory and experiment, we produce the ^{93m}Mo nuclei using the ^{12}C(^{86}Kr,5n) reaction at a beam energy of 559 MeV and transport the reaction residues to a detection station far away from the target area employing a secondary beam line. The isomer depletion is expected to occur during the slowdown process of the ions in the stopping material. In such a low γ-ray background environment, the signature of isomer depletion is not observed, and an upper limit of 2×10^{-5} is estimated for the excitation probability. This is consistent with the theoretical expectation. Our findings shed doubt on the previously reported NEEC phenomenon and highlight the necessity and feasibility of further experimental investigations for reexamining the isomer depletion under low γ-ray background.

New α-Emitting Isotope

A new α-emitting isotope ^{214}U, produced by the fusion-evaporation reaction ^{182}W(^{36}Ar,4n)^{214}U, was identified by employing the gas-filled recoil separator SHANS and the recoil-α correlation technique. More precise α-decay properties of even-even nuclei ^{216,218}U were also measured in the reactions of ^{40}Ar, ^{40}Ca beams with ^{180,182,184}W targets. By combining the experimental data, improved α-decay reduced widths δ^{2} for the even-even Po-Pu nuclei in the vicinity of the magic neutron number N=126 are deduced. Their systematic trends are discussed in terms of the N_{p}N_{n} scheme in order to study the influence of proton-neutron interaction on α decay in this region of nuclei. It is strikingly found that the reduced widths of ^{214,216}U are significantly enhanced by a factor of two as compared with the N_{p}N_{n} systematics for the 84≤Z≤90 and N<126 even-even nuclei. The abnormal enhancement is interpreted by the strong monopole interaction between the valence protons and neutrons occupying the π1f_{7/2} and ν1f_{5/2} spin-orbit partner orbits, which is supported by the large-scale shell model calculation.

Direct Measurement of the Astrophysical

Fluorine is one of the most interesting elements in nuclear astrophysics, where the ^{19}F(p,α)^{16}O reaction is of crucial importance for Galactic ^{19}F abundances and CNO cycle loss in first generation Population III stars. As a day-one campaign at the Jinping Underground Nuclear Astrophysics experimental facility, we report direct measurements of the essential ^{19}F(p,αγ)^{16}O reaction channel. The γ-ray yields were measured over E_{c.m.}=72.4-344 keV, covering the Gamow window; our energy of 72.4 keV is unprecedentedly low, reported here for the first time. The experiment was performed under the extremely low cosmic-ray-induced background environment of the China JinPing Underground Laboratory, one of the deepest underground laboratories in the world. The present low-energy S factors deviate significantly from previous theoretical predictions, and the uncertainties are significantly reduced. The thermonuclear ^{19}F(p,αγ)^{16}O reaction rate has been determined directly at the relevant astrophysical energies.

[Clinical outcomes for young patients with muscular invasive bladder cancer who received robot-assisted radical cystectomy].

Objective: To evaluate the clinical features, surgical effects and factors that may affect prognosis of muscular invasive bladder cancer in young people. Methods: The clinical data of young (aged 44 and below) patients with muscle invasive bladder cancer who underwent robot-assisted radical cystectomy at the First Affiliated Hospital of Zhengzhou University from October 1st, 2014 to October 31st, 2018 were retrospectively analyzed, which included age, gender, body mass index (BMI), tumor discovery method, tumor location, tumor size, comorbid diseases, operation time, intraoperative blood loss, urinary diversion method, postoperative complications, postoperative hospital stay, postoperative pathology and follow-up results. Results: A total of 24 patients were enrolled in this study, and 18(75%) were male and 6(25%) were female. The age was (40.4±3.5) years and the BMI was (24.7±2.5) kg/m2. At initial visit, there were 19(79%) patients who presented with hematuria, 4 (17%) with lower urinary tract symptoms, and 1(4%) was discovered by routine examination. Fifteen (62%) patients had single tumor, and 9(38%) had multiple tumors. The tumor diameter of 14(58%) patients were ≥3 cm and 3(13%) patients were combined with hydronephrosis. All patients received robot-assisted radical cystectomy successfully. The operative time was (325.8±57.2) min, and the blood loss during operation was 200(162,300) ml. The duration of postoperative hospital stay was 11(9,22) days. And according to different urinary diversion methods, 17(80%) patients had ileal orthotopic neobladder and 7(20%) had ileal conduit. For patients whose sexual nerves were preserved, 6(6/9) recovered their sexual function after one year of the surgery. The final pathological results showed that 16(67%) patients were in T2 stage, 7(29%) patients were in T3 stage and that 1(4%) patient in T4 stage. There were 6 (25%) patients with lymphatic metastasis, 8(33%) with low-grade papillary urothelial carcinoma, 14(58%) with high-grade papillary urothelial carcinoma, 1(4%) with adenocarcinoma and 1(4%) with small cell neuroendocrine carcinoma. Early complications of the patients were mostly slight, and only 2(8%) patients had Clavien Ⅲdegree complications, while few patients had late complications. The follow-up time was (26±12) months. During the follow-up time, there was 1(4%) patient who died because of liver and kidney failure. Distant metastasis occurred in 4(17%) cases and 1(4%) patient had urothelial carcinoma on one side of the ureter. Lymphatic metastasis (P=0.018) and ≥ T3 (P=0.038) stage were associated with the prognosis. Conclusions: For young patients with muscular invasive bladder cancer, the major initial presentation is hematuria, and most of them have advanced tumor stage and high malignant degree. Robot-assisted radical cystectomy is a safe and effective operation method with less postoperative complications, and protecting sexual nerve contributes to the recovery of sexual function. Advanced tumor stage (≥T3) and lymphatic metastasis are associated with distant metastasis and recurrence.

Large Isospin Asymmetry in

ß-delayed one-proton emissions of ^{22}Si, the lightest nucleus with an isospin projection T_{z}=-3, are studied with a silicon array surrounded by high-purity germanium detectors. Properties of ß-decay branches and the reduced transition probabilities for the transitions to the low-lying states of ^{22}Al are determined. Compared to the mirror ß decay of ^{22}O, the largest value of mirror asymmetry in low-lying states by far, with δ=209(96), is found in the transition to the first 1^{+} excited state. Shell-model calculation with isospin-nonconserving forces, including the T=1, J=2, 3 interaction related to the s_{1/2} orbit that introduces explicitly the isospin-symmetry breaking force and describes the loosely bound nature of the wave functions of the s_{1/2} orbit, can reproduce the observed data well and consistently explain the observation that a large δ value occurs for the first but not for the second 1^{+} excited state of ^{22}Al. Our results, while supporting the proton-halo structure in ^{22}Al, might provide another means to identify halo nuclei.

[Clinicopathological features and gene phenotypes of benign metastasizing leiomyoma].

Objective: To study the clinicopathological features, immunophenotypes and MED12 gene status in benign metastasizing leiomyoma (BML). Methods: Nine cases of BML diagnosed at the Affiliated Hospital of Qingdao University from 2012 to 2018 were collected, and the radiologic and histologic features were analyzed. The protein expression of leiomyosarcoma-related driver genes, including RB1, PTEN,ATRX,p16,p53, as well as ER,PR,CD34,FH, and Ki-67 were detected using immunohistochemistry, and the mutation status of MED12 gene exon 2 was detected by Sanger sequencing. Results: All the nine patients with BML were female, and the age range was 48 to 64 years (median 55 years). All patients had history of uterine fibroids. The morphologic features of BML were similar to a benign uterine leiomyoma and did not exhibit malignant characteristics. All cases were positive for ER and PR, and negative for CD34. In addition, RB1, PTEN, ATRX, and FH were positive in all cases (wild type), while p16 showed a focally positive pattern. P53 positive index was less than 5% (wild type), and Ki-67 positive index was less than 1%. Sanger sequencing was done in six BML samples; one sample harbored a nonsense mutation c. 142_144delinsTAA (p.Glu48Ter), and another exhibited a synonymy mutation (c.192C>T, p.Phe64=)and one missense mutation c.196C>T (p.Pro66Ser). Conclusions: The present study suggests that BML is a unique leiomyoma entity that is pathologically and genetically different from leiomyosarcomas and conventional uterine leiomyomas. Evaluating the genetic phenotype of BML, especially the expression of leiomyosarcoma-related driver genes protein and MED12 gene status, may be helpful in understanding the pathogenesis of BML and in its differentiation from leiomyosarcoma.

[CD20-positive T cell lymphoma: clinicopathological features of five cases].

Objective: To investigate the clinicopathological characteristics of the T cell lymphomas with CD20 expression, and to better understand this rare entity. Methods: Two-hundred cases of T-cell lymphoma diagnosed in the Department of Pathology of the Affiliated Hospital of Qingdao University from November 2016 to February 2020 were examined, and 5 cases of CD20-positive T-cell lymphomas were identified and included. Combined with clinical data and review of the literature, the clinicopathological characteristics of the disease were analyzed. Results: The five patients were all male, and had an average age of 56 years (range, 47 to 64 years). There were 2 cases of monomorphic epitheliotropic intestinal T-cell lymphoma, 2 cases of mycosis fungoides (1 case was plaque stage and the other was tumor stage) and 1 case of indolent T-cell lymphoproliferative disorder of the gastrointestinal tract. Immunohistochemistry showed that all 5 cases expressed multiple T cell markers (CD3/CD4/CD5/CD7/CD8) and only one of B cell markers (CD20). Three of the 5 cases were negative for CD20 at the first diagnosis, while CD20 was diffusely positive on the second biopsy from the recurrence or progression of the disease, without expression of CD79a or PAX5. Epstein-Barr encoding region (EBER) in situ hybridization was negative in all 5 cases. T-cell receptor gene analysis showed monoclonal rearrangement of ß or/and δ chains;Ig rearrangements were all polyclonal. None of the five patients were treated with rituximab, and 4 patients survived with disease and 1 patient survived without disease at the end of follow-up. Among them, the patient with mycosis fungoides at the cancerous stage has progressed rapidly and had poor quality of life. Conclusions: CD20-positive T-cell lymphoma is extremely rare. Its prognosis is closely related to the type of T-cell lymphoma, clinical stage and initial therapeutic effect. However, the expression of CD20 indicates the recurrence or progression of the disease, and the prognosis is relatively poor. When CD3 expression is absent in T-cell lymphoma, it is easy to be misdiagnosed as B-cell lymphoma. The combination of multiple immunohistochemical antibodies and molecular detection can improve the accuracy of diagnosis.

Genomic and transcriptional heterogeneity of multifocal hepatocellular carcinoma.

BACKGROUND: Hepatocellular carcinoma (HCC) often presents with multiple nodules within the liver, with limited effective interventions. The high genetic heterogeneity of HCC might be the major cause of treatment failure. We aimed to characterize genomic heterogeneity, infer clonal evolution, investigate RNA expression pattern and explore tumour immune microenvironment profile of multifocal HCC. PATIENTS AND METHODS: Whole-exome sequencing and RNA sequencing were carried out in 34 tumours and 6 adjacent normal liver tissue samples from 6 multifocal HCC patients. Protein expression of Ki67, AFP, P53, Survivin and CD8 was detected by immunohistochemistry. Fluorescence in situ hybridization was carried out to validate the amplification status of sorafenib-targeted genes. RESULTS: We deciphered genomic and transcriptional heterogeneity among tumours in each multifocal HCC patient including mutational profiles, copy number alterations, tumour evolutionary trajectory and tumour immune microenvironment profiles. Of note, sorafenib-targeted alterations were identified in the trunk of phylogenetic tree in only one out of the six patients, which may explain the relative low treatment response rate to sorafenib in clinical practice. Moreover, we demonstrated RNA expression patterns and tumour immune microenvironment profiles of all nodules. We found that RNA expression pattern was associated with Edmondson-Steiner grading. Based on the differential expression of 66 reported immune markers, unsupervised hierarchical clustering analysis of 34 nodules identified immune subsets: one low expression cluster with seven nodules and one high expression cluster with 11 nodules. CD8+ T cells were more enriched in nodules of the high expression cluster. CONCLUSIONS: Our study provided a detailed view of genomic and transcriptional heterogeneity, clonal evolution and immune infiltration of multifocal HCC. The heterogeneity of druggable targets and immune landscape might help interpret the clinical responsiveness to targeted drugs and immunotherapy for multifocal HCC patients.

Double Electron Capture in H

We have investigated the double electron capture process in the H^{+}+H^{-} collision system for energies from 60 eV to 20 keV. Despite the apparent simplicity of this highly correlated system, all previous calculations fail to reproduce the experimental total cross sections. Moreover, the latter exhibit oscillations that have been previously attributed to quantum interferences between the gerade and ungerade ionic states of the transient molecule formed during the collision. For this process, we present the absolute cross sections obtained from a fully correlated two-active-electron semiclassical atomic-orbital close-coupling approach. Our results reproduce well the experimental data in both magnitude and shape. Furthermore, we demonstrate that the oscillations stem from coherence effects between double electron capture and other two-electron inelastic channels, namely the transfer-excitation processes. This alternative interpretation is supported by a Rosenthal-like model based on a molecular treatment of the collision. Our results shed new light on this old but challenging problem.

A theoretical study of Ar8+-acetylene collisions at 1.2 MeV: Ionization and dissociation dynamics.

We theoretically study Ar8+-induced dissociation of C2H2 molecule at 1.2 MeV using the time-dependent density-functional theory non-adiabatically coupled to nuclear dynamics. We find that molecular dissociation depends strongly on the ionization at the initial stage and the collision configuration. A detailed analysis shows a correspondence between the charge state of [C2H2]q+ and the final fragments. A remarkable impact parameter effect provides deep insights of bond breakup and electronic transport. We analyze two typical sequential dissociation channels reported in experiments by tracking structural and electronic dynamics in real time. Our results provide better understanding of experiments. Moreover, the comparison between various exchange-correlation functionals reveals that electrons' correlation and self-interaction do not significantly impact the initial ionization and fragment distribution in the present study.