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1.
Front Microbiol ; 15: 1473441, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39351297

RESUMO

Background: We aim to establish a gestational diabetes mellitus (GDM) mouse model with mice fed with a high-fat diet (HFD) in comparison with pregnant mice with normal blood glucose levels to investigate the role of intestinal microbiota in the development of HFD-induced GDM. Methods: We divided healthy 6-week-old female C57BL mice into an HFD-induced GDM group and a normal diet group. Their bacterial flora and metabolites in intestinal fecal exosomes were co-analyzed using 16 s multi-region sequencing and compared. Findings: Alpha (α) diversity was lower within the model group compared to the control group. Beta (ß) diversity was significantly different between the two groups. The relative abundances of Lactobacillus, Actinomyces, Rothia, and Bacteroidetes were significantly different between the two groups. Fermentation and nitrate consumption were significantly higher in the GDM group. Multiple bacteria were associated with glycerophosphocholine, S-methyl-5'-thioadenosine, quinolinate, galactinol, deoxyadenosine, DL-arginine, and 2-oxoadenic acid. Interpretation: Imbalances in the production of Lactobacillus, Bacteroidetes, Actinomyces, and Rothia and their related metabolites may lead to metabolic disturbances in GDM. These indicators may be used to assess changes affecting the intestinal microbiota during pregnancy and thus help modulate diet and alter blood glucose.

2.
Sci Adv ; 10(39): eadq5299, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39331706

RESUMO

Cubic gauche nitrogen (cg-N) has received wide attention for its exceptionally high energy density and environmental friendliness. However, traditional synthesis methods for cg-N predominantly rely on high-pressure techniques or the utilization of nanoconfined effects using highly toxic and sensitive sodium azide as precursor, which substantially restrict its practical application. On the basis of the first-principles simulations, we found that adsorption of potassium on the cg-N surface exhibits superior stabilization compared to sodium. Then, we chose safer potassium azide as precursor for synthesizing cg-N. Through plasma-enhanced chemical vapor deposition treatment, the free-standing cg-N was successfully synthesized without the need for high-pressure and nanoconfined effects. It demonstrated excellent thermal stability up to 760 K, and then rapid and intense thermal decomposition occurred, exhibiting typical thermal decomposition behaviors of high-energy-density materials. The explosion parameters were also measured using laser-induced plasma spectroscopy. Our work has substantially promoted the practical application of cg-N as HEDMs.

3.
Cell Biosci ; 14(1): 112, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223689

RESUMO

Adamantinomatous craniopharyngioma (ACP) is a clinically aggressive tumor without effective treatment method. Previous studies proposed a paracrine tumorigenesis model, in which oncogenic ß-catenin induces senescence in pituitary stem cells and the senescent cells lead the formation of paracrine tumors through secretion of pro-tumorigenic factors. However, there lacks characterization on senescent cells in ACPs. Here, we profiled 12 ACPs with single-cell RNA and TCR-sequencing to elucidate the cellular atlas in ACPs and 3 of them were also subject to spatial sequencing to localize different subpopulations of the tumor cells. In total, we obtained the transcriptome profiles of 70,682 cells. Tumor cells, which were unambiguously identified through the cellular mutation status of the driver CTNNB1 mutations, were clustered into 6 subsets. The whorl-like cluster (WC) cells show distinct molecular features from the other tumor cells and the palisading epithelium (PE) cells consists of a proliferating subset. Other than typical PE and WC, we identified two novel subpopulations of the tumor cells. In one subpopulation, the cells express a high level of cytokines, e.g., FDCSP and S100A8/A9, and are enriched with the senescence-associated secretory phenotype (SASP) factors. Hematoxylin and eosin staining reveals that these SASP cells lack an ordered structures and their nuclei are elongated. In the other subpopulation, the cell sizes are small and they are tightly packed together with an unusual high density expressing a high level of mitochondrial genes (median 10.9%). These cells are the origin of the tumor developmental trajectories revealed by RNA velocity and pseudo-time analysis. Single-cell RNA and TCR analysis reveals that some ACPs are infiltrated with clonally expanded cytotoxic T cells. We propose a hypothesis that WC and PE are formed via different negative regulation mechanisms of the overactivated WNT/ß-catenin signaling which provides a new understanding on the tumorigenesis of ACPs. The study lays a foundation for future studies on targeting senescent cells in ACPs with senolytic compounds or other therapeutic agents.

4.
BMC Bioinformatics ; 25(1): 259, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39112940

RESUMO

BACKGROUND: Effective identification of differentially expressed genes (DEGs) has been challenging for single-cell RNA sequencing (scRNA-seq) profiles. Many existing algorithms have high false positive rates (FPRs) and often fail to identify weak biological signals. RESULTS: We present a novel method for identifying DEGs in scRNA-seq data called RankCompV3. It is based on the comparison of relative expression orderings (REOs) of gene pairs which are determined by comparing the expression levels of a pair of genes in a set of single-cell profiles. The numbers of genes with consistently higher or lower expression levels than the gene of interest are counted in two groups in comparison, respectively, and the result is tabulated in a 3 × 3 contingency table which is tested by McCullagh's method to determine if the gene is dysregulated. In both simulated and real scRNA-seq data, RankCompV3 tightly controlled the FPR and demonstrated high accuracy, outperforming 11 other common single-cell DEG detection algorithms. Analysis with either regular single-cell or synthetic pseudo-bulk profiles produced highly concordant DEGs with the ground-truth. In addition, RankCompV3 demonstrates higher sensitivity to weak biological signals than other methods. The algorithm was implemented using Julia and can be called in R. The source code is available at https://github.com/pathint/RankCompV3.jl . CONCLUSIONS: The REOs-based algorithm is a valuable tool for analyzing single-cell RNA profiles and identifying DEGs with high accuracy and sensitivity.


Assuntos
Algoritmos , Perfilação da Expressão Gênica , Análise de Sequência de RNA , Análise de Célula Única , Análise de Célula Única/métodos , Perfilação da Expressão Gênica/métodos , Análise de Sequência de RNA/métodos , Transcriptoma/genética , Humanos , Software
5.
Neuroimage Clin ; 43: 103641, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39032208

RESUMO

OBJECTIVE: The pathogenesis of depression in patients with Parkinson's disease (PD) is poorly understood. Therefore, this study aimed to explore the changes in γ-aminobutyric acid (GABA) and glutamate plus glutamine (Glx) levels in patients with PD with or without depression determined using MEscher-GArwood Point Resolved Spectroscopy (MEGA-PRESS). MATERIALS AND METHODS: A total of 83 patients with primary PD and 24 healthy controls were included. Patients with PD were categorized into depressed PD (DPD, n = 19) and nondepressed PD (NDPD, n = 64) based on the 17-item Hamilton Depression Rating Scale. All participants underwent T1-weighted imaging and MEGA-PRESS sequence to acquire GABA+ and Glx values. The MEGA-PRESS sequence was conducted using 18.48 mL voxels in the left thalamus and medial frontal cortex. The GABA+, Glx, and creatine values were quantified using Gannet 3.1 software. RESULTS: The GABA+ and Glx values were not significantly disparate between patients with PD and controls in the thalamus and medial frontal cortex. However, the levels of N-acetyl aspartate/creatine and choline/creatine in the left thalamus were significantly lower in patients with PD than in controls (P = .031, P = .009). The GABA+/Water and GABA+/Creatine in the medial frontal cortex were higher in DPD than in NDPD (P = .001, P = .004). The effects of depression on Glx or other metabolite levels were not evident, and no significant difference in metabolite values was noted in the left thalamus among all groups (P > .05). CONCLUSIONS: GABA+ levels increased in the medial frontal cortex in DPD, which may be more closely related to depressive pathology. Thus, alterations in GABAergic function in special brain structures may be related to the clinical manifestations of PD symptoms, and hence mediating this function might help in treating depression in PD.


Assuntos
Depressão , Ácido Glutâmico , Glutamina , Espectroscopia de Ressonância Magnética , Doença de Parkinson , Ácido gama-Aminobutírico , Humanos , Masculino , Feminino , Doença de Parkinson/metabolismo , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/complicações , Pessoa de Meia-Idade , Ácido gama-Aminobutírico/metabolismo , Idoso , Depressão/metabolismo , Depressão/etiologia , Depressão/diagnóstico por imagem , Glutamina/metabolismo , Ácido Glutâmico/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Tálamo/metabolismo , Tálamo/diagnóstico por imagem
6.
J Colloid Interface Sci ; 667: 175-183, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38636219

RESUMO

Compared with layered materials such as graphite and transition metal disulfide compounds with highly anisotropic in-plane covalent bonds, it is inherently more challenging to obtain independent metallic two-dimensional films with atomic thickness. In this study, PtNi layered metallene nanobowls (LMBs) with multilayer atomic-scale nanosheets and bowl-like structures have been synthesized in one step using structural and electronic effects. The material has the advantage of catalyzing pH-universal hydrogen evolution reaction (HER). Compared with Pt/C, PtNi LMBs exhibited excellent HER activity and stability under all pH conditions. The overpotentials of 10 mA cm-2 at 0.5 M H2SO4, 1.0 M phosphate buffer and 1.0 M KOH were 14.8, 20.3, and 34.0 mV, respectively. Under acidic, neutral and alkaline conditions, the HER Faraday efficiencies reach 98.97%, 98.85%, and 99.04%, respectively. This study provides an example for the preparation of unique multilayer nanobowls, and also provides a basic research platform for the development of special HER materials.

7.
Small ; 20(32): e2310409, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38477694

RESUMO

Electrochemical nitrite reduction reaction ( NO 2 - RR ${\mathrm{NO}}_{\mathrm{2}}^{\mathrm{ - }}{\mathrm{RR}}$ ), as a green and sustainable ammonia synthesis technology, has broad application prospects and environmental friendliness. Herein, an unconventional p-d orbital hybridization strategy is reported to realize the fabrication of defect-rich CuSb porous nanonetwork (CuSb PNs) electrocatalyst for NO 2 - RR ${\mathrm{NO}}_{\mathrm{2}}^ - {\mathrm{RR}}$ . The crystalline/amorphous heterophase structure is cleverly introduced into the porous nanonetworks, and this defect-rich structure exposes more atoms and activated boundaries. CuSb PNs exhibit a large NH3 yield ( r N H 3 ${{r}_{{\mathrm{N}}{{{\mathrm{H}}}_{\mathrm{3}}}}}$ ) of 946.1 µg h-1 m cat - 1 ${\mathrm{m}}_{{\mathrm{cat}}}^{ - {\mathrm{1}}}$ and a high faradaic efficiency (FE) of 90.7%. Experimental and theoretical studies indicate that the excellent performance of CuSb PNs results from the defect-rich porous nanonetworks structure and the p-d hybridization of Cu and Sb elements. This work describes a powerful pathway for the fabrication of p-d orbital hybrid defect-rich porous nanonetworks catalysts, and provides hope for solving the problem of nitrogen oxide pollution in the field of environment and energy.

8.
iScience ; 27(2): 108993, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38327786

RESUMO

The rapid development of nuclear energy posed a great threat to the environment and human health. Herein, two hydroxyl-functionalized hyper-crosslinked polymers (PIHCP-1 and PIHCP-2) containing different electron active sites have been synthesized via Friedel-Crafts alkylation reaction of the polyimides. The resulting polymers showed a micro/mesoporous morphology and good thermal and chemical stability. Rely on the high porosity and multi-active sites, the PIHCPs show an ultrahigh iodine uptake capacity reached 6.73 g g-1 and the iodine removal efficiency from aqueous solution also reaches 99.7%. Kinetic analysis demonstrates that the iodine adsorption on PIHCPs was happened on the heterogeneous surfaces in the form of multilayer chemisorption. Electrostatic potential (ESP) calculation proves the great contribution of hydroxyl groups on the iodine capture performance. In addition, the iodine capture efficiency of both adsorbents can be maintained over 91% after four cyclic experiments which ensures their good recyclability for further practical applications.

9.
Chin Med J (Engl) ; 137(7): 859-870, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37565822

RESUMO

BACKGROUND: Adamantinomatous craniopharyngioma (ACP) is the commonest pediatric sellar tumor. No effective drug is available and interpatient heterogeneity is prominent. This study aimed to identify distinct molecular subgroups of ACP based on the multi-omics profiles, imaging findings, and histological features, in order to predict the response to anti-inflammatory treatment and immunotherapies. METHODS: Totally 142 Chinese cases diagnosed with craniopharyngiomas were profiled, including 119 ACPs and 23 papillary craniopharyngiomas. Whole-exome sequencing (151 tumors, including recurrent ones), RNA sequencing (84 tumors), and DNA methylome profiling (95 tumors) were performed. Consensus clustering and non-negative matrix factorization were used for subgrouping, and Cox regression were utilized for prognostic evaluation, respectively. RESULTS: Three distinct molecular subgroups were identified: WNT, ImA, and ImB. The WNT subgroup showed higher Wnt/ß-catenin pathway activity, with a greater number of epithelial cells and more predominantly solid tumors. The ImA and ImB subgroups had activated inflammatory and interferon response pathways, with enhanced immune cell infiltration and more predominantly cystic tumors. Mitogen-activated protein kinases (MEK/MAPK) signaling was activated only in ImA samples, while IL-6 and epithelial-mesenchymal transition biomarkers were highly expressed in the ImB group, mostly consisting of children. The degree of astrogliosis was significantly elevated in the ImA group, with severe finger-like protrusions at the invasive front of the tumor. The molecular subgrouping was an independent prognostic factor, with the WNT group having longer event-free survival than ImB (Cox, P = 0.04). ImA/ImB cases were more likely to respond to immune checkpoint blockade (ICB) therapy than the WNT group ( P <0.01). In the preliminary screening of subtyping markers, CD38 was significantly downregulated in WNT compared with ImA and ImB ( P = 0.01). CONCLUSIONS: ACP comprises three molecular subtypes with distinct imaging and histological features. The prognosis of the WNT type is better than that of the ImB group, which is more likely to benefit from the ICB treatment.


Assuntos
Craniofaringioma , Neoplasias Hipofisárias , Humanos , Criança , Craniofaringioma/genética , Craniofaringioma/metabolismo , Craniofaringioma/patologia , Prognóstico , Multiômica , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/patologia , Via de Sinalização Wnt
10.
Plast Reconstr Surg ; 153(3): 539e-548e, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-37010462

RESUMO

BACKGROUND: According to the volume restoration theory, lower facial fat compartments tend to selectively atrophy or hypertrophy with age. The aim of this study was to demonstrate age-related changes in lower facial fat compartments using computed tomography, with strict control of the body mass index and underlying diseases. METHODS: This study included 60 adult women in three age-based categories. The thicknesses of the jowl, labiomandibular, and chin fat compartments were measured using computed tomographic images. The distribution and arrangement of facial blood vessels were further analyzed to provide evidence of the safety of rejuvenation strategies based on the facial volumetric theory. RESULTS: The inferior part of the superficial jowl fat compartment and deep jowl fat compartment thickened with age. The deep layer of the labiomandibular fat compartment thinned with age, and the superficial layer thickened with age. The deep and superficial layers of the chin compartments thickened with age. The facial vein passes through the lower mandibular border at the anterior edge of the masseter muscle and moves upward, perpendicular to the lower mandibular border. The high-risk area of the facial artery had an angle of approximately 45 degrees to the lower mandibular border. CONCLUSIONS: This study suggests that with age, selective thickening or thinning occurs in different lower facial fat compartments. The mandible and masseter muscle were used as reference markers to analyze the courses of the facial artery and facial vein, which can help clinicians to reduce vascular injury.


Assuntos
Face , Mandíbula , Adulto , Humanos , Feminino , Face/diagnóstico por imagem , Queixo , Tomografia Computadorizada por Raios X , Músculo Masseter
11.
Phys Chem Chem Phys ; 25(29): 19824-19833, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37455551

RESUMO

Hydrogen, as the smallest atom and a key component of water, can penetrate into materials in various forms (e.g., atoms, molecules), which has significant effects on their properties; hence, the diffusion behavior of hydrogen has aroused widespread attention. One of the major compositions in the Earth's interior is MgO. Thus, the diffusion behavior of hydrogen in MgO under high pressure is vital for understanding the water cycle in the Earth's interior. However, the hydrogen diffusion behavior in MgO under high pressure is still poorly understood. Herein, the hydrogen diffusion behaviors in MgO with increasing pressure are systematically investigated in the framework of first-principles methods. Our results show that separated H atoms tend to converge to form H2 molecules, and H2 molecules tend to gather together. The energy barriers of both H and H2 diffusion in MgO increase with pressure. Notably, our results illustrate that hydrogen prefers to diffuse in solid MgO in its molecular state even under high pressure. Furthermore, the attempt frequency of hydrogen in MgO increases with temperature, while it decreases with pressure. This study will deepen our understanding of hydrogen diffusion behavior in MgO under high pressure and provide guidance for studies on particle diffusion in solid materials under extreme conditions.

12.
Sci Rep ; 13(1): 3049, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36810626

RESUMO

The molecular biological differences between cyst walls and those in solid bodies are the foundation of the outcomes. In this study, the CTNNB1 mutations were confirmed by DNAsequencing; CTNNB1 expression levels were detected by PCR; the differences between solid bodies and cyst walls in proliferative capacity and tumor stem cell niches were assessed by immunohistochemistry; the effect of the residual cyst wall on recurrence was assessed by follow-up. Mutations in the CTNNB1 in the cyst wall and the solid body were identical in each case. No differences were found in the transcriptional level of CTNNB1 between the cyst walls and the solid bodies (P = 0.7619). The cyst wall showed a pathological structure similar to the solid body. Proliferative capacity of cyst walls was stronger than that of solid body (P = 0.0021), and ß-catenin nuclear positive cells (cell clusters) in cyst walls were more than that in solid tumor (P = 0.0002). The retrospective 45 ACPs showed residual cyst wall was significantly associated with tumor recurrence or regrowth (P = 0.0176). Kaplan-Meier analysis showed there was a significant difference in the prognosis between GTR and STR (P < 0.0001).The cyst wall of ACP contained more tumor stem cell niches which could lead to the recurrence. According to the above-mentioned, a special attention to the management of the cyst wall should be paid.


Assuntos
Craniofaringioma , Cistos , Neoplasias Hipofisárias , Humanos , Estudos Retrospectivos , Craniofaringioma/genética , Neoplasias Hipofisárias/patologia , beta Catenina/metabolismo , Mutação
13.
Magn Reson Imaging ; 96: 50-59, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36403863

RESUMO

PURPOSE: To evaluate the performance of different chemical exchange saturation transfer (CEST) metrics for grading gliomas with semiautomatically defined regions of interest (ROIs). METHODS: Thirty-eight adult subjects were included, including 23 high-grade gliomas and 15 low-grade gliomas confirmed by histopathology. The B0-corrected CEST z-spectra were first calculated with magnetization transfer ratio asymmetry (MTRasym) analysis at frequency offsets of 3.5, 3, 2.5, 2, 1.5, and 1 ppm to obtain the fit-free metrics and subsequently fitted with three Lorentzian functions denoting direct water saturation (DS), amide proton transfer (APT), and combined semisolid magnetization transfer and nuclear Overhauser enhancement (MT & NOE) effects to derive the fit-based metrics. Wilcoxon rank-sum test was performed to determine if a statistically significant difference was present in the CEST metrics between low- and high-grade gliomas. Receiver operating characteristic (ROC) curves were used to evaluate the differentiation of CEST metrics between low- and high-grade gliomas. Pearson correlation coefficients were employed to evaluate the correlations of CEST metrics. RESULTS: For the fit-free metrics, the highest areas under the curve (AUCs) of 0.85, 0.88, and 0.88, corresponding to MTRasym, MTRnormref (normalization by the reference scan), and MTRRex (subtraction of inverse z-spectra), respectively, were obtained at 3 ppm across various frequency offsets. In addition, the AUCs generated from the fit-based metrics (0.88-0.90) were higher than those generated from the fit-free metrics at 3 ppm. CONCLUSION: The results of this preliminary study indicate that fit-free CEST metrics at 3 ppm are superior to the other frequency offsets for grading human brain gliomas. The fit-based metrics manifested improved differentiation between low- and high-grade gliomas compared to the fit-free CEST metrics.


Assuntos
Neoplasias Encefálicas , Glioma , Adulto , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/patologia , Imageamento por Ressonância Magnética/métodos , Glioma/diagnóstico por imagem , Glioma/patologia , Prótons , Curva ROC , Convulsões , Amidas
14.
Eur Urol Open Sci ; 46: 88-95, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36506256

RESUMO

Background: Ductal carcinoma of the prostate (DCP) is a rare type of prostate cancer (PCa) with a higher degree of infiltration and worse prognosis than acinar adenocarcinoma of the prostate (ACP). Previous reports comparing DCP and ACP have not been very reliable and involved small sample sizes. Objective: To assess differences in mortality between ACP and DCP in a large-scale study. Design setting and participants: Data were downloaded from the Surveillance, Epidemiology, and End Results database in June 2022. Data for 823 939 patients diagnosed with PCa from 2004 to 2019 were examined, excluding cases with survival data missing or pathological types other than DCP and ACP. Outcome measurements and statistical analysis: Prognostic and risk factors for DCP were analyzed by generating a propensity score-matched cohort of DCP and ACP cases (1:5). Adjusted Cox models were constructed to determine hazard ratios (HRs) with 95% confidence intervals (CIs) for cancer-specific mortality (CSM) and overall mortality (OM). Results and limitations: A total of 822 607 cases (99.8%) has ACP and 1332 (0.2%) had DCP. In comparison to ACP, age at diagnosis was significantly lower for DCP (≤66 yr: 38.0% vs 50.7%; p < 0.001) and a higher proportion of DCP patients distant metastases (13.7% vs 5.1%; p < 0.001). In comparison to the ACP group, significantly higher proportions of the DCP group underwent surgery (66.1% vs 38.1%; p < 0.001), radiotherapy (13.7% vs 3.1%; p < 0.001), or systemic therapy (18.2% vs 3.3%; p < 0.001). However, the median overall survival time was significantly shorter for DCP patients (44.0 vs 73.0 mo; p < 0.001). DCP patients also had higher risk of CSM (HR 2.07, 95% CI 1.68-2.56; p < 0.001) and OM (HR 2.73 95% CI 2.42-3.08; p < 0.001) after propensity score matching to adjust for the influence of baseline variables. Subgroup analysis showed that DCP patients who had surgical treatment had better CSM than those without surgery, while DCP patients with regional and lower stage had better OM than those with distant stage (both p < 0.05 for interaction). Conclusions: The risk of CSM and OM is significantly higher for DCP than for ACP. Earlier detection (lower stage) and surgical treatment are beneficial factors for DCP prognosis. Patient summary: We studied survival rates for two different types of prostate cancer. We found that survival is worse for the rarer ductal carcinoma of the prostate (DCP) than for the more common acinar adenocarcinoma of the prostate. Both early diagnosis when the cancer is at a lower stage and surgical treatment are beneficial for survival in patients with DCP.

15.
J Phys Chem Lett ; 13(32): 7448-7453, 2022 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-35930621

RESUMO

Superionic ice with oxygen in a face-centered cubic (fcc) sublattice is ascribed to the origin of magnetic fields of Uranus and Neptune, since the melting temperature (Tm) of fcc-superionic ice is believed to be higher than the isentropes of ice giants. However, precisely measuring the fcc-superionic phase experimentally remains a difficult task. The majority of the systematic investigations of its Tm were performed using perfect oxygen fcc-sublattice computations, which could result in superheating and overestimation of Tm. On the basis of the ab initio molecular dynamics method and the model with H2O vacancy, we avoid superheating and obtain a much lower Tm than previous reports, indicating that fcc-superionic ice cannot exist in the interiors of Uranus and Neptune. Further simulations with the two-phase method justify the conclusion. The results suggest that superheating should be seriously treated when simulating the phase diagram of other hydrogen-related superionic states, which are widely used to understand the properties of ice giants, Earth, and Venus.

17.
Phys Chem Chem Phys ; 24(30): 18179-18184, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35861250

RESUMO

Based on the hybrid functional, we find that at 0 GPa, pristine CsV3Sb5 has a magnetic moment of 0.28 µB per vanadium atom, which is suppressed at a pressure of 2.5 GPa resulting in a spin-crossover. Since the ground state of CsV3Sb5 with charge density wave (CDW) distortion is a non-magnetic state, the magnetic moment of V atoms in pristine CsV3Sb5 will be suppressed by the temperature-induced CDW transition at 94 K. The schematic evolution of magnetic moments as functions of pressure and temperature is presented. At low temperature, CsV3Sb5 is a rare example of materials hosting a pressure-induced magnetic moment, and we suggest that the effects of magnetic moments of V atoms should be considered for understanding its properties.

18.
World Neurosurg ; 165: e148-e158, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35660482

RESUMO

OBJECTIVE: Papillary craniopharyngioma (PCP) was previously believed to occur only in adults. Sporadic pediatric PCP (PPCP) confirmed by detection of BRAF V600E mutation has been reported since 2018, but is often misdiagnosed before being diagnosed definitively. We aimed to evaluate PPCP characteristics and propose diagnostic criteria for prompt diagnosis, seeking to reduce patient morbidity and mortality and reduce costs linked to misdiagnosis. METHODS: This study included 5 patients with PPCPs whose data were retrieved retrospectively from among 1032 patients with craniopharyngiomas admitted to Sanbo Brain Hospital Management Group from March 2017 to May 2021. Patients' demographics, clinical presentation, tumor imaging characteristics, histopathologic results, surgical approaches, and postoperative outcomes were analyzed. RESULTS: PPCP was misdiagnosed intraoperatively as sellar abscess (n = 4) or Rathke cleft cyst (n = 1). Preoperative magnetic resonance imaging showed that all tumors were under the saddle diaphragm, and the cyst wall was enhanced (n = 5). Computed tomography scans showed scattered high-density signs (n = 4). No recurrence was noted after complete resection. Postoperative hypothalamic dysfunction was mild. BRAF V600E mutation was confirmed in all cases by sequencing and immunohistochemistry. Immunohistochemistry showed granulation and inflammation and MPO, CD3, CD20, CD38, CD68, and CD163 were positively expressed. CONCLUSIONS: Misdiagnosis of PPCP is responsible for failed surgical treatment. We propose that prompt diagnosis of PPCP can be achieved if preoperative magnetic resonance images show the tumor under saddle diaphragm with tumor wall enhancement and computed tomography scans show high-density signs scattered in the tumor, which leads to safe, effective tumor resection. Our proposed diagnosis and treatment strategy for PPCP reduces morbidity and mortality.


Assuntos
Cistos do Sistema Nervoso Central , Craniofaringioma , Neoplasias Hipofisárias , Adulto , Cistos do Sistema Nervoso Central/diagnóstico por imagem , Cistos do Sistema Nervoso Central/genética , Criança , Craniofaringioma/diagnóstico por imagem , Craniofaringioma/genética , Humanos , Imageamento por Ressonância Magnética , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/genética , Proteínas Proto-Oncogênicas B-raf/genética , Estudos Retrospectivos
19.
Front Mol Biosci ; 9: 806727, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35495630

RESUMO

Background: Telomerase reverse transcriptase promoter (TERT-p) mutation has been frequently found, but associated with contrary prognosis, in both low-grade gliomas and glioblastomas. For the low-grade gliomas (Grades II-III), TERT-p mutant patients have a better prognosis than the wildtype patients, whereas for the GBMs (Grade IV), TERT-p mutation is related to a poor prognosis. We hypothesize that there exist high-risk patients in LGGs who share GBM-like molecular features, including TERT-p mutation, and need more intensive treatment than other LGGs. A molecular signature is needed to identify these high-risk patients for an accurate and timely treatment. Methods: Using the within-sample relative expression orderings of gene pairs, we identified the gene pairs with significantly stable REOs, respectively, in both the TERT-p mutant LGGs and GBMs but with opposite directions in the two groups. These reversely stable gene pairs were used as the molecular signature to stratify the LGGs into high-risk and low-risk groups. Results: A signature consisting of 21 gene pairs was developed, which can classify LGGs into two groups with significantly different overall survival. The high-risk group has a similar genetic mutation profile and a similar survival profile as GBMs, and these high-risk tumors may progress to a more malignant state. Conclusion: The 21 gene-pair signature based on REOs is capable of identifying high-risk patients in LGGs and guiding the clinical choice for appropriate and timely intervention.

20.
Brief Bioinform ; 23(3)2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35368072

RESUMO

Liquid chromatography-mass spectrometry-based quantitative proteomics can measure the expression of thousands of proteins from biological samples and has been increasingly applied in cancer research. Identifying differentially expressed proteins (DEPs) between tumors and normal controls is commonly used to investigate carcinogenesis mechanisms. While differential expression analysis (DEA) at an individual level is desired to identify patient-specific molecular defects for better patient stratification, most statistical DEP analysis methods only identify deregulated proteins at the population level. To date, robust individualized DEA algorithms have been proposed for ribonucleic acid data, but their performance on proteomics data is underexplored. Herein, we performed a systematic evaluation on five individualized DEA algorithms for proteins on cancer proteomic datasets from seven cancer types. Results show that the within-sample relative expression orderings (REOs) of protein pairs in normal tissues were highly stable, providing the basis for individualized DEA for proteins using REOs. Moreover, individualized DEA algorithms achieve higher precision in detecting sample-specific deregulated proteins than population-level methods. To facilitate the utilization of individualized DEA algorithms in proteomics for prognostic biomarker discovery and personalized medicine, we provide Individualized DEP Analysis IDEPAXMBD (XMBD: Xiamen Big Data, a biomedical open software initiative in the National Institute for Data Science in Health and Medicine, Xiamen University, China.) (https://github.com/xmuyulab/IDEPA-XMBD), which is a user-friendly and open-source Python toolkit that integrates individualized DEA algorithms for DEP-associated deregulation pattern recognition.


Assuntos
Neoplasias , Proteoma , Humanos , Espectrometria de Massas/métodos , Neoplasias/genética , Proteoma/análise , Proteômica/métodos , Software
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