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2.
Phys Chem Chem Phys ; 26(11): 8695-8703, 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-37947451

ABSTRACT

Zintl-phase materials have attracted significant research interest owing to the interplay of magnetism and strong spin-orbit coupling, providing a prominent material platform for axion electrodynamics. Here, we report the single-crystal growth, structure, magnetic and electrical/thermal transport properties of the antiferromagnet layer Zintl-phase compound ß-EuIn2As2. Importantly, the new layered structure of ß-EuIn2As2, in rhombohedral (R3̄m) symmetry, contains triangular layers of Eu2+ ions. The in-plane resistivity ρ(H, T) measurements reveal metal behavior with an antiferromagnetic (AFM) transition (TN ∼ 23.5 K), which is consistent with the heat capacity Cp(H, T) and magnetic susceptibility χ(H, T) measurements. Negative MR was observed in the temperature range from 2 K to 20 K with a maximum MR ratio of 0.06. Unique 4f7J = S = 7/2 Eu2+ spins were supposed magnetically order along the c-axis. The Seebeck coefficient shows a maximum thermopower |Smax| of about 40 µV K-1. The kink around 23 K in the Seebeck coefficient originates from the effect of the antiferromagnetic phase on the electron band structure, while the pronounced thermal conductivity peak at around 10 K is attributed to the phonon-phonon Umklapp scattering. The results suggest that the Eu2+ spin arrangement plays an important role in the magnetic, electrical, and thermal transport properties in ß-EuIn2As2, which might be helpful for future potential technical applications.

3.
Zhonghua Wei Chang Wai Ke Za Zhi ; 26(12): 1179-1186, 2023 Dec 25.
Article in Chinese | MEDLINE | ID: mdl-38110280

ABSTRACT

Objective: To evaluate the efficacy and safety of cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) in the treatment of pseudomyxoma peritonei (PMP). Methods: In this descriptive case series study, we retrospective analyzed the records of PMP patients treated with CRS and HIPEC between January 2013 and June 2023 at Affiliated Cancer Hospital and Institute of Guangzhou Medical University. The inclusion criteria were as follows: (1) Aged 18 to 75 years and nonpregnant women. (2) Histologically confirmed diagnosis of pseudomyxoma peritonei. (3) Karnofsky Performance Scale (KPS)>70. (4) The functions of major organs such as the heart, liver, lungs, and kidneys can tolerate major surgery for long periods of time. (5) No evidence of extra-abdominal metastasis. Patients with extensive intra-abdominal adhesions or severe infectious diseases were excluded. The main outcomes were overall survival (OS) and postoperative major complications. The postoperative major complications were graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events (version 5.0). We used the peritoneal cancer index (PCI) score to quantitatively assess the peritoneal metastases and the completeness of cytoreduction (CCR) score at the end of surgery (CCR-0 and CCR-1 considered to be complete CRS). Results: A total of the 186 PMP patients with a median age of 56 (interquartile range extremes (IQRE), 48-64) years were included, 65 (34.9%) males and 121 (65.1%) females. The median peritoneal cancer index (PCI) score was 28 (20-34). Appendiceal origin accounted for 91.4%. Histological types were low grade in 99 patients (53.2%), high grade in 57 patients (30.6%), and 55 patients (29.6%) received complete cytoreduction (CCR-0/1). The median operative duration was 300 (211-430) minutes for all patients. Treatment-related 30-day mortality was 2.7%; 90-day mortality 4.3%; reoperation 1.6%; and severe morbidity 43.0%. Within the entire series, anemia(27.4%), electrolyte disturbance(11.6%), and hypoalbuminemia(7.5%) were the most frequent major complications (grade 3-4). The incidences of gastrointestinal anastomotic leakage, abdominal bleeding, and abdominal infection were 2.2%, 2.2%, and 4.3%, respectively. After a median follow-up of 38.1 (95%CI:31.2-45.1) months, the 5-year OS was 50.3% (95%CI: 40.7%-59.9%) with a median survival time of 66.1 (95%CI: 43.1-89.1) months. The survival analysis showed that patients with pathological low grade, low PCI, and low CCR score had better survival with statistically significant differences (all P<0.05). Further stratified into complete and incomplete CRS subgroups, the 5-year OS of the CCR-0 and CCR-1 subgroups was 88.9% (95%CI: 68.3%-100.0%) and 77.6% (95%CI: 62.7%-92.5%), respectively; and 42.0% (95%CI: 29.5%-54.5%) in the CCR-2/3 subgroup. Conclusions: CRS and HIPEC may result in a long-term survival benefit for PMP patients with acceptable perioperative morbidity and mortality. This strategy, when complete CRS is possible, could significantly prolong survival for strictly selected patients at experienced centers.


Subject(s)
Appendiceal Neoplasms , Hyperthermia, Induced , Peritoneal Neoplasms , Pseudomyxoma Peritonei , Male , Humans , Female , Pseudomyxoma Peritonei/drug therapy , Pseudomyxoma Peritonei/pathology , Hyperthermic Intraperitoneal Chemotherapy/adverse effects , Cytoreduction Surgical Procedures/adverse effects , Peritoneal Neoplasms/secondary , Retrospective Studies , Combined Modality Therapy , Postoperative Complications/etiology , Survival Rate
4.
J Phys Condens Matter ; 35(30)2023 May 05.
Article in English | MEDLINE | ID: mdl-37094581

ABSTRACT

The trigonal CaAl2Si2-type structure CaMn2P2has been reported undergoing an exotic first order phase transition at the critical temperatureTN=69.5K. In this paper, we present the optical spectra for theab-plane of CaMn2P2single crystal from 300 K to 10 K for the first time. In the real part of the optical conductivity spectraσ1(ω), a direct gap could be determined at all temperatures without any Drude term visible, i.e., the sample goes through the first order phase transition from one insulator state to the other insulator state. At higher energy, an asymmetric sharp interband transition peak appears in allσ1(ω) spectra, which indicates a divergence of the joint density of states. This sharp peak could be well described by the two dimensional van Hove singularity function. In particular, this peak is very sensitive to the first order phase transition, especially the peak positionEtwhose the most prominent blue shift occurs only when the first order transition happens. Our data and analysis reveal that the first order phase transition leads to a weak partial re-normalization of the band structure. Our study will be useful in further investigations about the mechanism of the first order phase transition in the insulator.

5.
Zhonghua Wei Chang Wai Ke Za Zhi ; 22(12): 1115-1117, 2019 Dec 25.
Article in Chinese | MEDLINE | ID: mdl-31874525

ABSTRACT

Hyperthermic intraperitoneal chemotherapy (HIPEC) has a unique effect on the prevention and treatment of peritoneal metastasis from malignancies. Recently, the first prospective, multicenter, randomized controlled clinical trial of HIPEC to prevent the development of peritoneal metastasis after curative surgery for patients with locally advanced colon cancer was published in the "Lancet Gastroenterol Hepatol" (COLOPEC). Regrettably, no significant difference was observed in 18-month peritoneal metastasis-free survival between postoperative adjuvant HIPEC and standard systemic chemotherapy for patients with T4 stage or perforated colon cancer. However, we wonder whether we might achieve better outcomes by further optimizing the following issues: (1) We propose that the inclusion criteria for that trial may not be entirely reasonable, which included pT4N0-2M0 and perforation. Additionally, we found that 91% of patients underwent HIPEC 5-8 weeks after primary tumor resection. (2) The imbalance in starting time of postoperative systemic chemotherapy between the two groups may have a negative impact.(3) Nine patients with peritoneal metastasis preceding HIPEC might weaken the potential efficacy of HIPEC. (4) We wonder whether HIPEC using high-dese oxaliplatin (460 mg/m(2)) perfusing 30 minutes for one cycle is the optimal regimen. Therefore, we are planning to conduct a randomized controlled trial (HIPEC-06) in accordcance with the characteristics of Chinese patients, to explore the clinical efficacy of curative surgery combined with HIPEC in the treatment of cT4 colorectal cancer.


Subject(s)
Antineoplastic Agents/administration & dosage , Colorectal Neoplasms/therapy , Hyperthermia, Induced/methods , Oxaliplatin/administration & dosage , Peritoneal Neoplasms/therapy , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/pathology , Colorectal Neoplasms/surgery , Combined Modality Therapy , Humans , Peritoneal Neoplasms/drug therapy , Peritoneal Neoplasms/secondary , Peritoneal Neoplasms/surgery
6.
Beijing Da Xue Xue Bao Yi Xue Ban ; 51(6): 1178-1181, 2019 Dec 18.
Article in Chinese | MEDLINE | ID: mdl-31848526

ABSTRACT

A 58-year-old female was referred to our department with intermittent suffocation for 1.5 years, aggravated for a month. 1.5 years before she developed oral ulcer, raynaud phenomenon, proteinuria, bilateral pleural effusion, ANA and anti-dsDNA positive. This patient was diagnosed with systemic lupus erythematosus (SLE). After given hormones, hydroxychloroquine sulfate (HCQ), her symptom relieved soon. The patient stopped her pills 1 year ago. One month ago, she had chest tightness, increased urine foam, and suffered from oliguria. Her admission medical examination: blood pressure (BP) 130/80 mmHg, conjunctiva pale, and lower lung breath sounds reduced. There was no tenderness, rebound pain and abdominal muscle tension in the abdomen. Liver and spleen rib inferior, mobile dullness negative, and lower extremity edema. Blood routine tests were performed with hemoglobin (HGB) 57 g/L. Urine routine: BLD (3+). 24-hour urinary protein 3.2 g. serum albumin 20.5 g/L, C-reactive protein (CRP) 12.85 mg/L, erythrocyte sedimentation rate (ESR) 140 mm/h. Antinuclear antibody (ANA) (H)1:10 000, anti-dsDNA antibody 1:3 200; anti-Smith antibody, anti-U1-snRNP/Sm antibody were positive, blood complement 3(C3) 0.43 g/L, complement 4(C4) 0.07 g /L. Anticardiolipin antibody (ACL), anti-ß2-GP1, lupus anticoagulant (LA) were negative; HRCT suggested bilateral medial pleural cavity product liquid. Admission diagnosis: SLE lupus nephritis, anemia, pleural effusion, and hypoproteinemia. We treated her with methylprednisolone 1 000 mg×3 d, late to 48 mg/d and cyclophosphamide 1.0 g, HCQ 0.2 g bid, gamma globulin 10 g×5 d. Day 2 of treatment, this patient developed acute right upper quadrant pain, not accompanied by nausea, vomiting, blood stool and diarrhea. Antipyretic antispasmodic treatment was invalid, after the morning to ease their own abdominal pain. Day 4 of treatment, daytime blood HGB 77 g/L. Bilateral renal vascular ultrasound: bilateral renal artery blood flow velocity was reduced. The abdominal pain of the above symptoms recurred at night, BP was 120/80 mmHg, and no positive signs were found on abdominal examination. No abnormality was found in the vertical abdominal plain film. Blood routine examination: HGB 53 g/L, Plasma D dimer 2 515 µg/L, amylase in hematuria was normal, the stool occult blood was negative. Abdominal computed tomography (CT): normal structure of right adrenal gland disappeared, irregular mass shadow could be seen in adrenal region, CT value was about 50 HU. Morphological density of left adrenal gland was not abnormal. The retroperitoneum descended along the inferior vena cava to the right iliac blood vessel and showed a bolus shadow. The density of some segments increased. The lesion involved the right renal periphery and reached the left side of abdominal aorta. Most lesions surrounded the inferior vena cava, the right renal vein and part of the small intestine. The boundary between the upper lesion and the vena cava was unclear. Iodinecontaining contrast agent was taken orally. No sign of contrast agent overflowing was found in the abdominal cavity. Hematoma and exudative changes were considered in retroperitoneum. CONCLUSION of contrast-enhanced ultrasound of blood vessels: The retroperitoneal inferior vena cava (volume 3.5 cm×3.5 cm×1.5 cm) was hypoechoic and had no blood flow lesion. The adrenal gland had a high possibility of origin. Left renal vein thrombosis extended to inferior vena cava. According to the above data, it was analyzed that the cause of retroperitoneal hematoma of the patient was left adrenal vein thrombosis caused by hypercoagulable state, which led to vascular rupture and hemorrhage caused by increased vascular pressure in adrenal gland. Therefore, on the basis of continuing to actively treat the primary disease, and on the basis of dynamic observation of no active hemorrhage for 3 days, the anticoagulant therapy was continued with 10 mg/d of apixaban. Clinical symptoms were gradually eased, HGB did not decrease. Two weeks later, the ultrasonic examination showed that the irregular cluster hypoechoic range behind the inferior vena cava was significantly smaller than that before (1.8 cm×1.2 cm×0.7 cm). Abdominal CT examination after 1 month showed that there was no abnormal morphological density of bilateral adrenal glands and basic absorption of retroperitoneal exudation. Adrenal hemorrhage is uncommon. SLE with adrenal hemorrhage is rarer. In SLE patients, especially those complicated with APS, if abdominal pain accompanied by HGB decrease occurs, except after gastrointestinal hemorrhage, the possibility of adrenal hemorrhage should be warned.


Subject(s)
Antiphospholipid Syndrome , Lupus Erythematosus, Systemic , Antibodies, Anticardiolipin , Aorta, Abdominal , Female , Hemorrhage , Humans , Middle Aged
7.
Eur Rev Med Pharmacol Sci ; 23(18): 8058-8067, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31599431

ABSTRACT

OBJECTIVE: Due to the increase in human life expectancy, a higher number of individuals are experiencing age-related cognitive impairments. Therefore, it is important to investigate the methods to tackle the effects of aging. MATERIALS AND METHODS: The mice were divided into the following groups: the aging mice (male, 20 months) and young mice (male, 2 months) were pairing-housed together in the same cage and lasted for at least one month (Aging-Young). The following tests were performed for the mice in different groups: Open field test, Morris water maze (MWM) test, Contextual fear conditioning test, Novel Object Recognition (NOR) test, Pain threshold test, Olfactory habituation/dishabituation test, T-maze test, Electrophysiological recordings. RESULTS: In this study, we housed aging and young mice together, and found that the paired housing for one-month improved the learning and memory of the aging mice. These mice exhibited better performance on the Morris water maze (MWM) test, a longer freezing duration in the contextual fear conditioning test, a higher alternation rate in the T-maze test, and an increased preference for novel objects in the novel object recognition (NOR) test. The paired housing with young mice also improved the impaired long-term potentiation (LTP) in aging mice. CONCLUSIONS: Our results suggest that the paired housing with young mice has beneficial effects on learning and memory of aging mice. The manipulation of the systemic environment may, therefore, provide a new strategy for aging rejuvenation.


Subject(s)
Aging/psychology , Alzheimer Disease/psychology , Behavior, Animal , Cognitive Aging/psychology , Housing, Animal , Prefrontal Cortex/physiopathology , Social Environment , Aging/physiology , Alzheimer Disease/physiopathology , Animals , Cognitive Aging/physiology , Conditioning, Psychological , Excitatory Postsynaptic Potentials , Exploratory Behavior , Habituation, Psychophysiologic , Long-Term Potentiation , Maze Learning , Mice , Pain Threshold
8.
J Phys Condens Matter ; 31(40): 405701, 2019 Oct 09.
Article in English | MEDLINE | ID: mdl-31242466

ABSTRACT

We report magnetic susceptibility, resistivity and optical spectroscopy study on single crystal sample DySb. It exhibits extremely large magnetoresistance (XMR), and a magnetic phase transition from paramagnetic (PM) to antiferromagnetic (AFM) state at about 10 K. A 'screened' plasma edge at about 4000 cm-1 is revealed by optical measurement, which suggests that the material has a low carrier density. With decreasing temperature, the 'screened' plasma edge shows a blue shift, possibly due to a decrease of the effective mass of carriers. Notably, an anomalous temperature dependent midinfrared absorption feature is observed in the vicinity of the 'screened' plasma edge. In addition, it can be connected to the inflection point in the real part of the dielectric function [Formula: see text], the frequency of which exactly tracks the temperature dependent 'screened' plasma frequency. This phenomena can be explained by the appearance of a coupled electron-plasmon 'plasmaron' feature.

9.
Beijing Da Xue Xue Bao Yi Xue Ban ; 50(6): 986-990, 2018 Dec 18.
Article in Chinese | MEDLINE | ID: mdl-30562769

ABSTRACT

OBJECTIVE: To investigate the clinical characteristics of rheumatoid arthritis (RA) patients with malignant tumor. METHODS: Retrospective summary was made of 1 562 in patients of RA from January 2011 to June 2017. In the study, 74 RA patients with malignant tumor were reviewed and analyzed, and the general conditions, tumor types, RA and tumor onset sequence, and the medication situation were analyzed. RESULTS: The incidence of malignant tumor in the patients with rheumatoid arthritis in our center was 4.16%. The 74 patients were complicated with malignant tumor, of whom 53 were female, and 21 male. The age of RA at presentation was (52.6±17.8) years. The average disease duration of malignant tumor was (63.4 ± 12.7) years. The onset time of rheumatoid arthritis was earlier than that of malignant tumors in 51 cases (51/74), with an average of (17.2±14.2) years between 2 and 60 years. The incidence of malignant tumor was earlier than that of rheumatoid arthritis in 16 cases (16/74), with an average of (6.2±5.9) years between 1 and 21 years, of which 10 cases were sex hormone related tumors. Seven cases (7/74) were diagnosed with RA at the same time, and the time interval between the two diseases was within 1 year. All the patients were over 60 years old with digestive tract tumors. All the 7 patients showed polyarthritis, significantly increased erythrocyte sedimentation rate and C-reactive protein, including 4 rheumatoid factor positive cases and 2 anti-CCP antibody positive cases. The effect of non-steroidal anti-inflammatory drugs and traditional drugs to improve the condition of the disease was poor in the 7 patients, and the condition was relieved after using low-dose glucocorticoids. Gastrointestinal tumors, breast and reproductive system tumors were the most common, followed by respiratory, urological and blood system tumors. CONCLUSION: The risk in patients of rheumatoid arthritis complicated with malignant tumor is higher than that of the general population. A variety of factors play an important role in cancer risk of RA, including disease activity, some estrogen metabolites, the use of drugs and so on. Therefore, all RA patients should be screened for malignant tumor during diagnosis, and malignant tumor surveillance is mandatory for all rheumatoid arthritis patients after diagnosis.


Subject(s)
Arthritis, Rheumatoid , Neoplasms , Adult , Aged , Arthritis, Rheumatoid/blood , Arthritis, Rheumatoid/complications , Autoantibodies , C-Reactive Protein/analysis , Female , Humans , Male , Middle Aged , Neoplasms/complications , Neoplasms/immunology , Peptides, Cyclic , Retrospective Studies , Rheumatoid Factor/blood
11.
Clin Lab ; 63(11): 1949-1953, 2017 Nov 01.
Article in English | MEDLINE | ID: mdl-29226653

ABSTRACT

BACKGROUND: Early detection and management of colorectal cancer (CRC) and colorectal adenoma (CRA) reduces the mortality and morbidity of CRC, but there is a lack of ideal circulation biomarkers. METHODS: A total of 80 patients with early-stage CRC and CRA and 30 healthy controls were included in this preliminary study. Plasma samples were collected before colonoscopy and prepared for measurement of microRNA193b and soluble uPAR. RESULTS: Plasma level of miR-193b was decreased through the normal-adenoma-carcinoma sequence with no significant difference between patients with CRC and advanced CRA. The AUC of ROC curve evaluating the value of miR-193b in discriminating patients with early stage CRC or advanced CRA from patients with non-advanced CRA or normal control subjects was 0.849 (95% CI 0.773 - 0.923, p < 0.001). Significant alteration of plasma suPAR is only observed in CRC group (p < 0.001). CONCLUSIONS: Plasma miR-193b may be a novel candidate biomarker for screening patients with early-stage CRC and advanced CRA.


Subject(s)
Adenoma/blood , Carcinoma/blood , Colorectal Neoplasms/blood , MicroRNAs/blood , Receptors, Urokinase Plasminogen Activator/blood , Adenoma/diagnosis , Aged , Biomarkers, Tumor/blood , Carcinoma/diagnosis , Case-Control Studies , Colorectal Neoplasms/diagnosis , Female , Humans , Male , Mass Screening , Middle Aged , Pilot Projects
12.
J Nutr Health Aging ; 21(9): 943-953, 2017.
Article in English | MEDLINE | ID: mdl-29083434

ABSTRACT

OBJECTIVES: The associations between nutritional status and lifestyle factors have not been well established. This study aimed to investigate the prevalence of poor nutrition and to examine the relationships between nutritional status and unhealthy lifestyle and other related factors among the elderly. METHODS: This cross-sectional study was conducted in Liaobu Town, Dongguan city, China. A total of 708 community-dwelling older adults aged ≥60 years were recruited by stratified random sampling. Data on sociodemographic characteristics, health and lifestyle factors, and the Mini Nutritional Assessment (MNA) scores were collected using structured questionnaires via face-to-face interviews. A multivariate logistic regression model was constructed to identify the risk factors of poor nutrition. RESULTS: The prevalence of malnutrition among the elderly adults in this study was 1.3%, and 24.4% were at risk of malnutrition (RM). Poor nutrition was significantly associated with female gender, older age, lower education, a high number of self-reported chronic diseases, and hospitalization in the last year. Unhealthy lifestyle factors associated with poor nutrition included current smoking status, higher alcohol consumption, lack of physical activity, longer duration of sitting, negative attitude towards life, and a poor family relationship. CONCLUSIONS: While the prevalence of malnutrition was low, RM was high in the elderly population in China. The determinants of malnutrition were explored and the relationships between nutritional status and unhealthy lifestyle factors were examined. The results of this study provide information for future longitudinal studies with multi-factorial interventional design in order to determine the effects of the causal relationships.


Subject(s)
Life Style , Nutritional Status/physiology , Aged , Aged, 80 and over , China/epidemiology , Cross-Sectional Studies , Female , Geriatric Assessment/methods , Humans , Male , Middle Aged , Prevalence , Risk Factors
13.
Sci Rep ; 7(1): 14178, 2017 10 27.
Article in English | MEDLINE | ID: mdl-29079790

ABSTRACT

Unconventional superconductivity often emerges at the border of long-range magnetic orders. Understanding the low-energy charge dynamics may provide crucial information on the formation of superconductivity. Here we report the unpolarized/polarized optical conductivity study of high quality MnP single crystals at ambient pressure. Our data reveal two types of charge carriers with very different lifetimes. In combination with the first-principles calculations, we show that the short-lifetime carriers have flat Fermi sheets which become gapped in the helimagnetic phase, causing a dramatic change in the low-frequency optical spectra, while the long-lifetime carriers are anisotropic three-dimensional like which are little affected by the magnetic transitions and provide major contributions to the transport properties. This orbital-dependent charge dynamics originates from the special crystal structure of MnP and may have an influence on the unconventional superconductivity and its interplay with helimagnetism at high pressures.

14.
J Phys Condens Matter ; 29(45): 455603, 2017 11 15.
Article in English | MEDLINE | ID: mdl-29049031

ABSTRACT

K2Cr3As3 is a newly discovered quasi-1D superconductor with a T c = 6.1 K and an upper critical field µ 0 H c2(0) ≈ 40 T three times larger than the Pauli paramagnetic limit µ 0 H p that is suggestive of a spin-triplet Cooper pairing. In this paper, we have investigated the effects of hydrostatic pressure on its T c and µ 0 H c2 by measuring the ac magnetic susceptibility χ'(T) under magnetic fields at various hydrostatic pressures up to 7.5 GPa. The major findings include: (1) T c is suppressed gradually to below 2 K at 7.5 GPa; (2) the estimated µ 0 H c2(0) decreases dramatically to below µ 0 H p above ~2 GPa and becomes slight lower than the orbital limiting field [Formula: see text] estimated from the initial slope of upper critical field via [Formula: see text] = -0.73T cdH c2/[Formula: see text] in the clean limit; (3) the estimated Maki parameter α = √2[Formula: see text]/H p drops from 4 at ambient pressure to well below 1 at P > 2 GPa, suggesting the crossover from Pauli paramagnetic limiting to orbital limiting in the pair breaking process upon increasing pressure. These observations suggested that the application of hydrostatic pressure could drive K2Cr3As3 away from the ferromagnetic instability and lead to a breakdown of the spin-triplet pairing channel. We have also made a side-by-side comparison and discussed the distinct effects of chemical and physical pressures on the superconducting properties of K2Cr3As3.

15.
J Phys Condens Matter ; 29(40): 405603, 2017 Oct 11.
Article in English | MEDLINE | ID: mdl-28695842

ABSTRACT

We report resistivity, specific heat and optical spectroscopy measurements on single crystal samples of [Formula: see text] [Formula: see text] [Formula: see text] and [Formula: see text] [Formula: see text] [Formula: see text]. We observed clear temperature-induced spectral weight suppression below 4000 [Formula: see text] for both compounds in the conductivity spectra [Formula: see text], indicating the progressive formation of gap-like features with decreasing temperature. The suppressed spectral weight transfers mostly to the higher energy region. This observation reflects the presence of the correlation effect in the compounds. We attribute the correlation effect to the Co 3d electrons.

16.
Cell Death Differ ; 24(6): 1133, 2017 06.
Article in English | MEDLINE | ID: mdl-27636105

ABSTRACT

Retraction to: Cell Death Differ 2016;23(9):1471­1482. doi:10.1038/cdd.2016.32

17.
Phys Rev Lett ; 117(12): 127204, 2016 Sep 16.
Article in English | MEDLINE | ID: mdl-27689296

ABSTRACT

By combining angle-resolved photoemission spectroscopy and quantum oscillation measurements, we performed a comprehensive investigation on the electronic structure of LaSb, which exhibits near-quadratic extremely large magnetoresistance (XMR) without any sign of saturation at magnetic fields as high as 40 T. We clearly resolve one spherical and one intersecting-ellipsoidal hole Fermi surfaces (FSs) at the Brillouin zone (BZ) center Γ and one ellipsoidal electron FS at the BZ boundary X. The hole and electron carriers calculated from the enclosed FS volumes are perfectly compensated, and the carrier compensation is unaffected by temperature. We further reveal that LaSb is topologically trivial but shares many similarities with the Weyl semimetal TaAs family in the bulk electronic structure. Based on these results, we have examined the mechanisms that have been proposed so far to explain the near-quadratic XMR in semimetals.

18.
Nat Commun ; 7: 13037, 2016 10 06.
Article in English | MEDLINE | ID: mdl-27708255

ABSTRACT

Magnetic and superconducting ground states can compete, cooperate and coexist. MnP provides a compelling and potentially generalizable example of a material where superconductivity and magnetism may be intertwined. Using a synchrotron-based non-resonant X-ray magnetic diffraction technique, we reveal a spiral spin order in MnP and trace its pressure evolution towards superconducting order via measurements in a diamond anvil cell. Judging from the magnetostriction, ordered moments vanish at the quantum phase transition as pressure increases the electron kinetic energy. Spins remain local in the disordered phase, and the promotion of superconductivity is likely to emerge from an enhanced coupling to residual spiral spin fluctuations and their concomitant suppression of phonon-mediated superconductivity. As the pitch of the spiral order varies across the 3d transition metal compounds in the MnP family, the magnetic ground state switches between antiferromagnet and ferromagnet, providing an additional tuning parameter in probing spin-fluctuation-induced superconductivity.

19.
Cell Death Differ ; 23(9): 1471-82, 2016 Sep 01.
Article in English | MEDLINE | ID: mdl-27058318

ABSTRACT

Radioresistance is a major obstacle in successful clinical cancer radiotherapy, and the underlying mechanisms are not clear. Here we show that IKKα-mediated miR-196a biogenesis via interaction with Drosha regulates the sensitivity of nasopharyngeal carcinoma (NPC) cells to radiotherapy. Phosphorylation of IKKα at T23 site (p-IKKαT23) promotes the binding of IKKα to Drosha that accelerates the processing of miR-196a primary transcripts, leading to increased expressions of both precursor and mature miR-196a. Dephosphorylation of p-IKKαT23 downregulates miR-196a expression and promotes the resistance of NPC cells to radiation treatment. The miR-196a mimic suppresses while its inhibitor promotes the resistance of NPC to radiation treatment. Importantly, the expression of p-IKKαT23 is positively related to the expression of miR-196a in human NPC tissues, and expression of p-IKKαT23 and miR-196a is inversely correlated with NPC clinical radioresistance. Thus, our studies establish a novel mechanistic link between the inactivation of IKKαT23-Drosha-miR-196a pathway and NPC radioresistance, and de-inactivation of IKKαT23-Drosha-miR-196a pathway would be an efficient way to restore the sensitivity of radioresistant NPC to radiotherapy.

20.
Oncogene ; 35(12): 1483-92, 2016 Mar 24.
Article in English | MEDLINE | ID: mdl-26096930

ABSTRACT

Inhibition of the chaperone heat-shock protein 90 (HSP90) induces apoptosis, and it is a promising anti-cancer strategy. The mechanisms underpinning apoptosis activation following HSP90 inhibition and how they are modified during acquired drug resistance are unknown. We show for the first time that, to induce apoptosis, HSP90 inhibition requires the cooperation of multi BH3-only proteins (BID, BIK, PUMA) and the reciprocal suppression of the pro-survival BCL-2 family member MCL1, which occurs via inhibition of STAT5A. A subset of tumour cell lines exhibit dependence on MCL1 expression for survival and this dependence is also associated with tumour response to HSP90 inhibition. In the acquired resistance setting, MCL1 suppression in response to HSP90 inhibitors is maintained; however, a switch in MCL1 dependence occurs. This can be exploited by the BH3 peptidomimetic ABT737, through non-BCL-2-dependent synthetic lethality.


Subject(s)
HSP90 Heat-Shock Proteins/antagonists & inhibitors , Myeloid Cell Leukemia Sequence 1 Protein/genetics , Cell Line, Tumor , Humans , Peptidomimetics , STAT5 Transcription Factor/genetics , Tumor Suppressor Proteins/genetics
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