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2.
Phytochemistry ; 171: 112229, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31901474

RESUMO

Seven undescribed cycloartane triterpenoids, pseudolarnoids A-G, together with ten known ones, were isolated from the seeds of Pseudolarix amabilis (J. Nelson) Rehder. Their structures were elucidated on the basis of spectroscopic analysis, X-ray crystallography, and ECD data. Pseudolarnoids A-C are cycloartane triterpenoids with a unique 16S, 23R-spirolactone moiety. Pseudolarnoids F, G, and pseudolarolide C demonstrated potent antiviral effects on HSV-1 in vitro.

3.
Int J Cancer ; 146(1): 272-280, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31162842

RESUMO

Epstein-Barr virus (EBV)-associated gastric carcinomas (EBVaGCs) may account for 8-9% of all gastric cancer (GC) patients. All previous reports on EBVaGC were retrospective. Prospective study is warranted to evaluate the exact role of EBV status in predicting the prognosis of GC. It is of special interest to figure out whether dynamic detection of plasma EBV-DNA load could be a feasible biomarker for the monitor of EBVaGC. From October 2014 to September 2017, we consecutively collected GC patients (n = 2,760) from Sun Yat-sen University Cancer Center for EBER examination. We detected EBV-DNA load in plasma and tissue samples of EBVaGC patients at baseline. Subsequently, plasma EBV-DNA load was dynamically monitored in EBVaGC patients. The overall prevalence of EBVaGC is 5.1% (140/2,760). The incidence rate of EBVaGC decreased with advanced AJCC 7th TNM stage (p < 0.001), with the corresponding percentages of 9.3, 9.9, 6.7 and 1.4% for Stage I, II, III and IV patients. EBVaGC patients were predominately young males with better histologic differentiation and earlier TNM stage than EBV-negative GC (EBVnGC) patients. EBVaGC patients were confirmed to had a favorable 3-year survival rate (EBVaGC vs. EBVnGC: 76.8% vs. 58.2%, p = 0.0001). Though only 52.1% (73/140) EBVaGC patients gained detectable EBV-DNA and 43.6% (61/140) reached a positive cutoff of 100 copies/ml, we found the plasma EBV-DNA load in EBVaGC decreased when patients got response, while it increased when disease progressed. Our results suggested that plasma EBV-DNA is a good marker in predicting recurrence and chemotherapy response for EBVaGC patients.

4.
Oncogene ; 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31831835

RESUMO

The original version of this Article omitted the following from the Acknowledgements: Professor Stebbing sits on SABs for Celltrion, Singapore Biotech, Vor Biopharma, TLC Biopharmaceuticals and Benevolent AI, has consulted with Lansdowne partners, Vitruvian and Social Impact Capital and Chairs the Board of Directors for BB Biotech Healthcare Trust and Xerion Healthcare. This has now been corrected in both the PDF and HTML versions of the Article.

5.
Mol Oncol ; 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31670863

RESUMO

Hepatocellular carcinoma (HCC), with its ineffective therapeutic options and poor prognosis, represents a global threat. In the present study, we show that RAD52 motif 1 (RDM1), a key regulator of DNA double-strand break repair and recombination, is downregulated in HCC tissues and suppresses tumor growth. In clinical HCC samples, low expression of RDM1 correlates with larger tumor size, poor tumor differentiation, and unfavorable survival. In vitro and in vivo data demonstrate that knockdown of RDM1 increases HCC cell proliferation, colony formation, and cell population at G2/M phase, whereas RDM1 overexpression results in the opposite phenotypes. Mechanistically, RDM1 binds to the tumor suppressor p53 and enhances its protein stability. In the presence of p53, RDM1 suppresses the phosphorylation of Raf and ERK. Overexpression of p53 or treatment with ERK inhibitor significantly abolishes cell proliferation induced by the depletion of RDM1. In addition, overexpression of methyltransferase-like 3 markedly induces N6-methyladenosine modification of RDM1 mRNA and represses its expression. Taken together, our study indicates that RDM1 functions as a tumor suppressor and may be a potential prognostic and therapeutic factor for HCC.

6.
Environ Monit Assess ; 191(11): 704, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31673801

RESUMO

In light of ongoing changes in how humans interact with the environment, it is of great importance to quantitatively assess the impact of land use and cover change (LUCC) on ecosystems. Using a variety of methods, we analyzed land-use patterns and ecosystem service values (ESV) in 1990, 2000, and 2010; normalized difference vegetation index (NDVI) from 1982 to 2010 in the arid region of Northwest China; and quantitatively assessed the effects of LUCC on changes in NDVI and ESV. The results indicate the following: (1) From 1990 to 2010, the rate of increase in the amount of cropland and urban land was highest at 19.13% and 18.25%, respectively, followed by the rate for water cover (5.10%) and forest land (3.55%), while grassland experienced a reduction of 2.25%. (2) From 1990 to 2010, the total ESV increased by 1.82%. Changes in the amount of water cover and cropland were responsible for an increase in ESV of 1.42% and 1.10%, respectively, while the change in the amount of grassland was responsible for a decrease of 1.09%. Based on this, it seems likely that climate variability is a substantial cause of change in ESV. (3) From 1982 to 2010, NDVI showed an overall increase, first increasing significantly between 1982 and 2002 and then decreasing somewhat from 2002 to 2010. From 1990 to 2010, the contribution rate of LUCC to change in total NDVI was 26.74%, indicating that the contribution rate of climate variability to NDVI change was up to 73.26%. Therefore, over those 20 years, climate warming and humidification had an important impact on the development of ecosystems in the arid region of Northwest China.


Assuntos
Conservação dos Recursos Naturais/tendências , Produtos Agrícolas/crescimento & desenvolvimento , Monitoramento Ambiental/métodos , Poaceae/crescimento & desenvolvimento , Urbanização/tendências , China , Mudança Climática , Ecossistema , Florestas , Humanos
7.
Oncogene ; 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31754213

RESUMO

EGFR-mutant non-small-cell lung cancer (NSCLC) patients inevitably develop drug resistance when treated with EGFR tyrosine kinase inhibitors (TKIs). Systematic genetic analysis is important to understand drug-resistant mechanisms; however, the clinical significance of co-occurring genetic alterations at baseline, co-acquired mutations at progressive disease (PD), and the clonal evolution remain underinvestigated. We performed targeted sequencing of pre-treatment and PD tumor samples from 54 EGFR-mutant NSCLC patients. Ten additional patients were sequenced using whole-exome sequencing to infer the clonal evolution patterns. We observed a domain-dependent effect of PIK3CA mutation at baseline on patient progression-free survival (PFS). In addition, at baseline, 9q34.3/19p13.3 (NOTCH1/STK11/GNA11) showed a co-deletion pattern, which was associated with a significantly worse PFS (p = 0.00079). T790M-postive patients with other concurrent acquired oncogenic mutations had a significantly shorter PFS (p = 0.005). Besides acquired T790M mutation, chromosomal instability (CIN) related genes, including AURKA and TP53 alterations, were the most frequently acquired events. CIN significantly increased during TKI treatment in T790M-negative patients and is a candidate resistance mechanism to the first-generation TKIs. Clonal evolution analyses suggest that the composition and relationship among resistant subclones, particularly relationship with T790M subclone, affect patients' outcomes. Overall, our findings of novel co-occurring alterations and clonal evolution patterns can be served as predictive biomarkers to stratify patients and help to better understand the drug-resistant mechanism to TKIs.

8.
Adv Mater ; 31(49): e1903480, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31617626

RESUMO

Most of the state-of-the-art thermoelectric (TE) materials exhibit high crystal symmetry, multiple valleys near the Fermi level, heavy constituent elements with small electronegativity differences, or complex crystal structure. Typically, such general features have been well observed in those well-known TE materials such as Bi2 X3 -, SnX-, and PbX-based compounds (X = S, Se, and Te). The performance is usually high in the materials with heavy constituent elements such as Te and Se, but it is low for light constituent elements such as S. However, there is a great abnormality in Cu2 X-based compounds in which Cu2 Te has much lower TE figure of merit (zT) than Cu2 S and Cu2 Se. It is demonstrated that the Cu2 Te-based compounds are also excellent TE materials if Cu deficiency is sufficiently suppressed. By introducing Ag2 Te into Cu2 Te, the carrier concentration is substantially reduced to significantly improve the zT with a record-high value of 1.8, 323% improvement over Cu2 Te and outperforms any other Cu2 Te-based materials. The single parabolic band model is used to further prove that all Cu2 X-based compounds are excellent TE materials. Such finding makes Cu2 X-based compounds the only type of material composed of three sequent main group elements that all possess very high zT  s above 1.5.

9.
Br J Cancer ; 121(8): 640-646, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31523058

RESUMO

BACKGROUND: Small-cell lung cancer (SCLC) remains an aggressive cancer with short-term survival due to limited therapeutic options. Apatinib is a small-molecule tyrosine kinase inhibitor that selectively inhibits vascular endothelial growth factor receptor-2. This study aimed to investigate the efficacy and safety of apatinib in patients with extensive-stage (EC) SCLC who had progressed after two or three previous therapies. METHODS: Eligible patients were histologically confirmed ES-SCLC after two or three previous treatments, including a platinum-based regimen. Patients received apatinib at an initial dose of 500 mg once daily. The primary endpoint was the objective response rate. RESULTS: Forty patients were enrolled. At the data cut-off time (November 15, 2018), the median follow-up was 7.4 months; no patients remained on treatment, and five were still in follow-up. An objective response was achieved in 7 of 40 patients (17.5%) in the intention-to-treat population, and 7 of 38 patients (18.4%) in the per-protocol population. The median progression-free survival and overall survival were 3.0 months and 5·8 months, respectively. The most commonly observed grade 3 or greater treatment-related adverse events were hypertension, hand-foot syndrome, increased L-gamma-glutamyltransferase. CONCLUSIONS: Apatinib exhibited efficacy and an acceptable safety profile in previously heavily-treated ES-SCLC patients. Further exploration of apatinib in phase III trials is warranted. TRIAL REGISTRATION: NCT02945852.

10.
ACS Appl Mater Interfaces ; 11(35): 32151-32158, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31403765

RESUMO

ß-FeSi2 has been considered a promising material for thermoelectric applications, but its thermoelectric performance is greatly limited by the overhigh lattice thermal conductivity. In thermoelectrics, alloying an effective method to reduce the lattice thermal conductivity. In this study, we chose the Co-doped ß-FeSi2 (Fe0.94Co0.06Si2) as the matrix and then prepared a series of Ru alloyed Fe0.94-xRuxCo0.06Si2 (x = 0, 0.005, 0.01, 0.02, and 0.05). X-ray characterizations show that all samples crystallize in the ß-FeSi2 structure. The elemental mappings detect an inhomogeneous Ru distribution in Fe0.89Ru0.05Co0.06Si2, which is attributed to the different Ru solution contents in ε-FeSi and α-FeSi2+δ before the formation of ß-FeSi2 and the slow diffusion behavior of Ru during the annealing process. The Ru-alloying obviously reduces the lattice thermal conductivity via introducing the mass and strain field fluctuations to interrupt the phonon transports, while it has a weak effect on electrical transport properties. Finally, a maximum zT value of 0.33 at 900 K has been obtained for Fe0.89Ru0.05Co0.06Si2, which is about 27% higher than that for Fe0.94Co0.06Si2.

11.
J Psychopharmacol ; 33(12): 1491-1500, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31432769

RESUMO

PURPOSE: The transient receptor potential vanilloid 1 (TRPV1) is a nonselective cation channel that mediates synaptic modification in the nucleus accumbens (NAc). However, no study has yet examined the mechanism of TRPV1 in the NAc on cocaine reinstatement. We investigated the mechanism of TRPV1 in NAc on cocaine reinstatement using the conditioned place preference (CPP) test in mice. METHODS: We examined the effect of capsazepine (5 mg/kg, a TRPV1 antagonist, administered intraperitoneally (i.p.)), capsaicin (0.3 mg/kg, a TRPV1 agonist, administered i.p.), and genetic deletion of TRPV1 on the reinstatement of cocaine-induced CPP (15 mg/kg, administered i.p.). The expression of TRPV1 and Ca2+/calmodulin-mediated kinase II (CaMKII) in the NAc were determined after cocaine reinstatement. Microinjection of SB366791 (0.2 ng, a selective TRPV1 antagonist) in the NAc was assessed on SKF-81297 (1 µg, D1-like dopamine (DA) receptor agonist) primed cocaine reinstatement. RESULTS: Capsazepine suppressed and capsaicin potentiated cocaine CPP in the reinstatement phase. In addition, genetic deletion of TRPV1 inhibited cocaine-priming reinstatement. Cocaine reinstatement was mediated by increased TRPV1 expression in the NAc, which involves CaMKII. Microinjection of SB366791 in the NAc prevented the cocaine reinstatement evoked by microinjection of SKF-81297 in the NAc. CONCLUSIONS: These findings suggest that activation of TRPV1 mediates the stimulation of D1-like DA receptors and CaMKII in the NAc, resulting in the facilitation of cocaine reinstatement behaviors. Thus, our findings reveal a previously unknown TRPV1 mechanism in the reinstatement to drugs of abuse.

12.
ACS Appl Mater Interfaces ; 11(37): 34046-34052, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31454228

RESUMO

As one of the state-of-the-art phase-change materials, the stable Ge2Sb2Te5 hexagonal compound also exhibits decent thermoelectric performance with high electrical conductivity and low thermal conductivity. Nonetheless, the excessively high carrier concentration and low Seebeck coefficient are the bottlenecks to achieve high zT values. In this work, with the intention to optimize the electrical properties, indium was introduced as a potentially donor-like dopant in a series of Ge2-xInxSb2Te5 samples. The substitution of indium for germanium lowers the density of hole carriers and enhances the Seebeck coefficient. Noticeably, the room-temperature Seebeck coefficient of the doped samples can be three times as large as that of the pristine one, which obviously departures from the theoretically predicted Pisarenko relation based on the single parabolic band model. By virtue of DFT calculations and modeling, the remarkable enhancement of Seebeck coefficient was attributed to the doping-induced local distortion in the electronic density of states. Further insight reveals that indium doping amplifies the bonding character of Ge-Te adjacent to indium and enhances the atomic interaction along the c-axis. Due to the optimized electrical properties as well as the suppressed thermal conductivity, a maximal zT value of 0.78 was achieved in Ge1.85In0.15Sb2Te5 at 700 K, which is about 40% higher than that of the pristine sample.

13.
Adv Mater ; 31(29): e1807916, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31148307

RESUMO

The urgent need for ecofriendly, stable, long-lifetime power sources is driving the booming market for miniaturized and integrated electronics, including wearable and medical implantable devices. Flexible thermoelectric materials and devices are receiving increasing attention, due to their capability to convert heat into electricity directly by conformably attaching them onto heat sources. Polymer-based flexible thermoelectric materials are particularly fascinating because of their intrinsic flexibility, affordability, and low toxicity. There are other promising alternatives including inorganic-based flexible thermoelectrics that have high energy-conversion efficiency, large power output, and stability at relatively high temperature. Herein, the state-of-the-art in the development of flexible thermoelectric materials and devices is summarized, including exploring the fundamentals behind the performance of flexible thermoelectric materials and devices by relating materials chemistry and physics to properties. By taking insights from carrier and phonon transport, the limitations of high-performance flexible thermoelectric materials and the underlying mechanisms associated with each optimization strategy are highlighted. Finally, the remaining challenges in flexible thermoelectric materials are discussed in conclusion, and suggestions and a framework to guide future development are provided, which may pave the way for a bright future for flexible thermoelectric devices in the energy market.

14.
Mod Pathol ; 32(11): 1646-1656, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31231126

RESUMO

Programmed death ligand 1 (PD-L1) protein expression by immunohistochemistry is a promising biomarker for PD-1/PD-L1 blockade in hepatocellular carcinoma. There are a number of commercially available PD-L1 assays. Our study aimed to compare the analytical performance of different PD-L1 assays and evaluate the reliability of pathologists in PD-L1 scoring. Consecutive sections from tumor samples from 55 patients with surgically resected primary hepatocellular carcinoma were stained with four standardized PD-L1 assays (22C3, 28-8, SP142, and SP263). We also correlated the PD-L1 protein level by immunohistochemistry with the mRNA level of those genes associated with tumor immune microenvironment by the NanoString platform. Five pathologists independently assessed PD-L1 expression on tumor cells [tumor proportion score] together with tumor-infiltrating immune cells (combined positive score). The 22C3, 28-8, and SP263 assays had comparable sensitivity in detecting PD-L1 expression, whereas the SP142 assay was the least sensitive assay. The inter-assay agreement measured by intraclass correlation coefficients for the tumor proportion score and combined positive score were 0.646 and 0.780, respectively. The inter-rater agreement was good to excellent (the overall intraclass correlation coefficient for the tumor proportion score and combined positive score was 0.946 and 0.809, respectively). Pathologists were less reliable in scoring combined positive score than tumor proportion score, particularly when using the SP142 assay. Up to 18% of samples were misclassified by individual pathologists in comparison to the consensus score at the cutoff of combined positive score ≥ 1. The combined positive score by the 22C3 assay demonstrated the strongest correlation with immune-related gene mRNA signatures, closely followed by combined positive scores by the 28-8 and SP263 assays. In conclusion, the 22C3, 28-8, and SP263 assays are highly concordant in PD-L1 scoring and suggest the interchangeability of these three assays. Further improvement of the accuracy in assessing PD-L1 expression at a low cutoff is still necessary.

15.
J Mol Med (Berl) ; 97(8): 1213-1214, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31203376

RESUMO

In Figure 7f the panel for c-myc of MDA-MB-468 was erroneously duplicated. The corrected version of the figure is shown in this paper. This correction does not influence the conclusion of the study and we sincerely apologize for this oversight.

16.
Huan Jing Ke Xue ; 40(4): 1871-1877, 2019 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-31087931

RESUMO

Using artificial water, the simultaneous partial nitrification, ANAMMOX (anaerobic ammonium oxidation), and denitrification (SNAD) granular sludge process was started in a sequencing batch reactor (SBR), and then the ammonia concentration in the influent was reduced gradually. After stable operation for a period of time under the low ammonia concentration, sewage treated by a pre-precipitation process was used as a substrate to investigate the performance and stability of the SNAD granular sludge process. The results show that after the SNAD process was successfully started, the ammonia removal rate was greater than 98%, and total the nitrogen removal rate was about 89%. As the influent ammonia concentration decreased, the nitride-oxidizing bacteria (NOB) activity was increased and the total nitrogen removal rate gradually decreased to 75%. When the pre-precipitated domestic sewage (NH4+-N 52-63 mg·L-1, COD 99-123 mg·L-1) was used as the inflow, the average effluent removal rate of the total effluent was 73.2%, the effluent COD concentration was below 35 mg·L-1, and the maximum effluent ammonia nitrogen and total nitrogen concentration were 0.7 mg·L-1 and 12.8 mg·L-1. The ammonia and total nitrogen concentration in the continuous 30 day effluent reached the 1A level of the integrated discharge standard of water pollutants for municipal wastewater treatment, indicating that the removal of organics and nitrogen from domestic sewage was achieved efficiently and synchronously.

17.
Lung Cancer ; 131: 62-68, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31027700

RESUMO

PURPOSE: Anaplastic lymphoma kinase (ALK) is now a validated kinase target in non-small cell lung cancer (NSCLC). We implemented three ALK laboratory methodologies: fluorescence in situ hybridization (FISH), immunohistochemistry (IHC) and next-generation sequencing (NGS) to detect EML4-ALK fusions and compared the predictive value for Crizotinib efficacy in ALK-positive patients. METHODS: 55 ALK positive patients confirmed by at least one method were enrolled in the present study, of whom 45 cases were assessed by FISH, IHC and NGS concurrently, and another 10 cases only received IHC and NGS assessment for ALK status. RESULTS: IHC presented the uppermost positive rate (94.5%), followed by NGS (92.7%) and FISH(82.4%), among which IHC and NGS had the highest concordance rate of 87.3%. No difference was detected in ORR, DCR and PFS of ALK positive cases defined in three groups. Notably, NGS positive patients were correlated with a higher DCR and longer PFS compared to NGS negative cases (P = 0.02 and P = 0.09), while FISH and IHC status were not distinguishing in predicting the outcome of Crizotinib. TP53 concurrent mutation might reduce responsiveness to Crizotinib and worsen prognosis in ALK-rearranged NSCLC. CONCLUSION: FISH present a certain false-negative rate although considered the gold standard. Ventana-D5F3 IHC is qualified as a screening tool, while NGS positive may predict clinical benefit of Crizotinib more accurately, allowing efficient test for specific variants and concurrent genomic alterations.

18.
ACS Appl Mater Interfaces ; 11(13): 12632-12638, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30908005

RESUMO

Ag4SSe, named as aguilarite in mineralogy, belongs to the family of liquid-like superionic compounds at middle temperature, but its thermoelectric (TE) properties are rarely investigated so far. In this study, a series of Ag-deficient Ag4SSe samples have been synthesized by the melting-annealing method. Their crystal structures, phase transition features, and electrical and thermal transport properties have been systematically investigated. It is found that Ag4SSe allows a small amount of Ag deficiency inside the lattice without altering the initial crystal structure and phase transition feature. The stoichiometric Ag4SSe has a low TE figure of merit ( zT) of 0.24 at 613 K because of the overhigh carrier concentration. Introducing Ag deficiency in Ag4SSe significantly lowers the carrier concentration, yielding a greatly enhanced Seebeck coefficient and suppressed carrier thermal conductivity throughout the entire measured temperature range. A maximum TE zT of 0.53 is achieved at 493 K for Ag3.96SSe, about two times that for the stoichiometric Ag4SSe. The present study suggests that aguilarite Ag4SSe is a promising TE material applied at the middle temperature range.

19.
ACS Appl Mater Interfaces ; 11(14): 13433-13440, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30875476

RESUMO

Liquid-like binary Cu2-δX (X = S, Se, and Te) chalcogenides and their ternary solid solutions have gained notable attention in thermoelectrics due to their interesting and abnormal thermal and electrical transport properties. However, previous studies mainly focus on a single element alloying at either an anion or cation site whereas the investigation on cation/anion co-alloying is very rare so far. Here, a series of quaternary Cu2-2 xAg2 xSe1- xS x ( x = 0.01, 0.03, 0.05, 0.1, 0.15) liquid-like copper chalcogenide materials have been fabricated and the effects of Ag/S co-alloying on the thermoelectric properties of Cu2Se have been systematically studied. It is found that all compounds are mixed phases at room temperature but single cubic phase at high temperatures. The introduction of Ag and S in Cu2Se brings about a large mass fluctuation rather than strain field fluctuation that effectively suppresses the lattice thermal conductivity. Furthermore, on increasing the Ag and S contents, the high electrical conductivity of pristine Cu2Se is well tuned to the optimal range derived from the single parabolic band model analysis. Consequently, a peak zT of 1.6 at 900 K is achieved in Cu1.8Ag0.2Se0.9S0.1, which is about 33% higher than that of binary Cu2Se.

20.
Sci Adv ; 5(3): eaav4449, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30838333

RESUMO

Quantum materials represent one of the most promising frontiers in the quest for faster, lightweight, energy-efficient technologies. However, their inherent complexity and rich phase landscape make them challenging to understand or manipulate. Here, we present a new ultrafast electron calorimetry technique that can systematically uncover new phases of quantum matter. Using time- and angle-resolved photoemission spectroscopy, we measure the dynamic electron temperature, band structure, and heat capacity. This approach allows us to uncover a new long-lived metastable state in the charge density wave material 1T-TaSe2, which is distinct from all the known equilibrium phases: It is characterized by a substantially reduced effective total heat capacity that is only 30% of the normal value, because of selective electron-phonon coupling to a subset of phonon modes. As a result, less energy is required to melt the charge order and transform the state of the material than under thermal equilibrium conditions.

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