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1.
Nature ; 569(7754): 99-103, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31043727

RESUMEN

Since their discovery in 19601, metallic glasses based on a wide range of elements have been developed2. However, the theoretical prediction of glass-forming compositions is challenging and the discovery of alloys with specific properties has so far largely been the result of trial and error3-8. Bulk metallic glasses can exhibit strength and elasticity surpassing those of conventional structural alloys9-11, but the mechanical properties of these glasses are critically dependent on the glass transition temperature. At temperatures approaching the glass transition, bulk metallic glasses undergo plastic flow, resulting in a substantial decrease in quasi-static strength. Bulk metallic glasses with glass transition temperatures greater than 1,000 kelvin have been developed, but the supercooled liquid region (between the glass transition and the crystallization temperature) is narrow, resulting in very little thermoplastic formability, which limits their practical applicability. Here we report the design of iridium/nickel/tantalum metallic glasses (and others also containing boron) with a glass transition temperature of up to 1,162 kelvin and a supercooled liquid region of 136 kelvin that is wider than that of most existing metallic glasses12. Our Ir-Ni-Ta-(B) glasses exhibit high strength at high temperatures compared to existing alloys: 3.7 gigapascals at 1,000 kelvin9,13. Their glass-forming ability is characterized by a critical casting thickness of three millimetres, suggesting that small-scale components for applications at high temperatures or in harsh environments can readily be obtained by thermoplastic forming14. To identify alloys of interest, we used a simplified combinatorial approach6-8 harnessing a previously reported correlation between glass-forming ability and electrical resistivity15-17. This method is non-destructive, allowing subsequent testing of a range of physical properties on the same library of samples. The practicality of our design and discovery approach, exemplified by the identification of high-strength, high-temperature bulk metallic glasses, bodes well for enabling the discovery of other glassy alloys with exciting properties.

2.
Proc Natl Acad Sci U S A ; 119(19): e2116380119, 2022 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-35500124

RESUMEN

SignificanceThere is a common consensus that lode gold deposits mostly precipitated from metamorphic fluids via fluid boiling and/or fluid-rock interaction, but whether magmatic hydrothermal fluids and the mixing of such fluids with an external component have played a vital role in the formation of lode gold deposits remains elusive. We use garnet secondary ion mass spectrometry oxygen isotope analysis to demonstrate that the world-class Dongping lode gold deposit has been formed by multiple pulses of magmatic hydrothermal fluids and their mixing with large volumes of meteoric water. This study opens an opportunity to tightly constrain the origin of lode gold deposits worldwide and other hydrothermal systems that may have generated giant ore deposits in the Earth's crust.

3.
J Stroke Cerebrovasc Dis ; 33(6): 107682, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38522758

RESUMEN

OBJECTIVE: To assess the correlation between lesion location and swallowing function characteristics in post-stroke dysphagia (PSD) patients. MATERIALS AND METHODS: We enrolled 133 PSD. The patients were divided into supratentorial and infratentorial stroke groups. We compared the measurements in the videofluoroscopic swallowing study (VFSS) with 3ml and 5 ml of diluted and thickened barium liquid data between supratentorial and brainstem stroke groups. We further compared the difference of VFSS measurements between patients with left hemispheric or right hemispheric lesions (further divided into unilateral hemispheric cortical and subcortical subgroups) and brianstem leison stroke group.To explore the lesion location's effect on different bolus volume, the VFSS measurements of 3ml and 5ml in each subgroups were compared respectively. The measurements of VFSS included the oral transit time, soft palate elevation duration, hyoid bone movement duration (HMD), UES opening duration, pharyngeal transit duration (PTD), stage of ansition duration, and laryngeal closure duration (LCD), the upper esophageal sphincter opening (UESO), hyoid bone superior horizontal displacement, and hyoid bone anterior horizontal displacement. General swallowing function was assessed using the Penetration Aspiration Scale (PAS) and Functional Oral Intake Scale (FOIS). We performed the paired t-test, Spearman's correlation, and Kruskal-Wallis test analysis to characterize the parameters among the groups. RESULTS: Fifty-eight patients were assessed in the final analysis. The HMD (p = 0.019), PTD (p = 0.048) and LCD (p = 0.013) were significantly different between the supratentorial and brainstem lesion groups in 5ml volume. The HMD was significantly different (p = 0.045) between the left cortical and brainstem lesion groups. Significant differences in the HMD (p = 0.037) and LCD (p = 0.032) between the left subcortical and brainstem lesion groups were found in 5ml volume bolus. There was no group different when taking the 3ml volume bolus. Regarding the relationship between food bolus volume and swallowing functions, only the UESO demonstrated a significant difference in the subcortical lesion of the right hemisphere (p = 0.0032) compared the 3 ml and 5 ml volume bolus. The PTD demonstrated a moderate correlation with the PAS scores (r = 0.38, p = 0.0044). The HMD (r = 0.32, p = 0.018) and LCD (r = 0.29, p = 0.039) demonstrated weak correlations with the PAS scores. We did not identify any correlation between the VFSS parameters and FOIS scores in each subgroup level. CONCLUSION: The PSD with brainstem lesion shows more sever dysfunction in the pharyngeal phases. The left hemisphere was engaged in both the oral and pharyngeal phases. Lesions in the bilateral cortical, subcortical, and brainstem regions may impair sensory input.


Asunto(s)
Trastornos de Deglución , Deglución , Accidente Cerebrovascular , Grabación en Video , Humanos , Trastornos de Deglución/fisiopatología , Trastornos de Deglución/etiología , Trastornos de Deglución/diagnóstico , Trastornos de Deglución/diagnóstico por imagen , Masculino , Femenino , Anciano , Persona de Mediana Edad , Accidente Cerebrovascular/fisiopatología , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico , Fluoroscopía , Valor Predictivo de las Pruebas , Anciano de 80 o más Años , Factores de Tiempo , Factores de Riesgo , Estudios Retrospectivos
4.
J Am Chem Soc ; 145(14): 8261-8270, 2023 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-36976930

RESUMEN

The photocatalytic conversion of CO2 into C2+ products such as ethylene is a promising path toward the carbon neutral goal but remains a big challenge due to the high activation barrier for CO2 and similar reduction potentials of many possible multi-electron-transfer products. Herein, an effective tandem photocatalysis strategy has been developed to support conversion of CO2 to ethylene by construction of the synergistic dual sites in rhenium-(I) bipyridine fac-[ReI(bpy)(CO)3Cl] (Re-bpy) and copper-porphyrinic triazine framework [PTF(Cu)]. With these two catalysts, a large amount of ethylene can be produced at a rate of 73.2 µmol g-1 h-1 under visible light irradiation. However, ethylene cannot be obtained from CO2 by use of either component of the Re-bpy or PTF(Cu) catalysts alone; with a single catalyst, only monocarbon product CO is produced under similar conditions. In the tandem photocatalytic system, the CO generated at the Re-bpy sites is adsorbed by the nearby Cu single sites in PTF(Cu), and this is followed by a synergistic C-C coupling process which ultimately produces ethylene. Density functional theory calculations demonstrate that the coupling process between PTF(Cu)-*CO and Re-bpy-*CO to form the key intermediate Re-bpy-*CO-*CO-PTF(Cu) is vital to the C2H4 production. This work provides a new pathway for the design of efficient photocatalysts for photoconversion of CO2 to C2 products via a tandem process driven by visible light under mild conditions.

5.
J Neurosci Res ; 101(2): 245-255, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36345215

RESUMEN

Seizures are a frequent symptom of unruptured brain arteriovenous malformations (bAVMs). However, the brain regions responsible for these seizures remain unclear. To identify the brain regions causally involved in bAVM-related seizures, we retrospectively reviewed 220 patients with unruptured bAVMs. Using voxel-based lesion-symptom mapping (VLSM) analyses, we tested whether individual brain regions were associated with unruptured bAVM-related seizures. The result revealed that unruptured bAVMs causing seizures are anatomically heterogeneous at the voxel level. Subsequently, lesion network mapping (LNM) analyses was performed to determine whether bAVMs causing seizures belonged to a distributed brain network. LNM analyses indicated that these lesions were located in a functional network characterized by connectivity to the left caudate and precuneus. Moreover, the discrimination performance of the identified seizure network was evaluated in discovery set by calculating the individualized network damage score and was tested in validation set. Based on the calculated network damage scores, patients were divided into low-, medium-, and high-risk groups. The prevalence of seizures significantly differed among the three risk categories in both discovery (p = .003) and validation set (p = .004). Finally, we calculated the percentage of voxels in the canonical resting-state networks that overlapped with the seizure-susceptible brain regions to investigate the involvement of resting-state networks. With an involvement percentage over 50%, the frontoparietal control (82.9%), limbic function (76.7%), and default mode network (69.3%) were considered to be impacted in bAVM-related seizures. Our study identified the seizure-susceptible brain regions for unruptured bAVMs, which could be a plausible neuroimaging biomarker in predicting possible seizures.


Asunto(s)
Malformaciones Arteriovenosas , Convulsiones , Humanos , Estudios Retrospectivos , Convulsiones/diagnóstico por imagen , Convulsiones/etiología , Encéfalo/diagnóstico por imagen
6.
BMC Womens Health ; 23(1): 559, 2023 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-37891576

RESUMEN

BACKGROUND: Ovarian remnant syndrome (ORS) is a rare complication that occurs after oophorectomy, characterized by residual ovarian tissue causing pelvic pain, masses, and various symptoms. The clinical manifestations of ORS are nonspecific, and its diagnosis relies on histological examination. Since ORS typically represents a benign ovarian lesion, there have been few reported cases of malignant transformation. In this report, we presented a unique case of ovarian clear cell carcinoma (OCCC) arising from an ovarian remnant following salpingo-oophorectomy. CASE PRESENTATION: Our patient was a 47-year-old female initially diagnosed with uterine myoma. She had previously undergone cesarean section and unilateral salpingo-oophorectomy. Transvaginal ultrasound and computed tomography (CT) scans revealed a soft tissue mass adjacent to the right lateral wall of the myometrium. The patient opted for transabdominal hysterectomy, left adnexal resection, laparoscopic omentectomy, appendectomy, and pelvic and abdominal lymphadenectomy. The final pathology results confirmed the diagnosis of OCCC, consistent with ORS. The patient subsequently received six cycles of intravenous chemotherapy using the carboplatin/paclitaxel (TC) regimen (paclitaxel liposomes 175 mg/m², carboplatin AUC 5). After 3 years of follow-up, the patient's condition remained normal. CONCLUSION: ORS can significantly impact patients' quality of life and pose challenges for clinicians. Complete excision of ovarian tissue during the initial surgery is crucial in preventing ORS recurrence and potential malignant transformation of ovarian remnants.


Asunto(s)
Carcinoma , Neoplasias Ováricas , Humanos , Embarazo , Femenino , Persona de Mediana Edad , Neoplasias Ováricas/patología , Carboplatino/uso terapéutico , Cesárea , Calidad de Vida , Paclitaxel/uso terapéutico
7.
Glob Chang Biol ; 28(6): 2041-2052, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34935251

RESUMEN

Direct measuring of CO2  flux remains challenging for global lakes. The traditional sampling and gas transfer models used to estimate lake CO2  fluxes are variable and uncertain, and ice-covered periods are often excluded from the annual carbon budget. Here, the first longtime (2013-2017) direct measurement of CO2  flux by eddy covariance system over the largest saline lake (Qinghai lake) in the Qinghai-Tibet Plateau (QTP) revealed that ice-covered period draws large amounts of CO2 from the atmosphere (-0.87 ± 0.38 g C m-2 d-1 ), a value more than twice the CO2  flux rate during the ice-free period (-0.41 ± 0.35 g C m-2 d-1 ). The total CO2 uptake by all saline lakes on the QTP was estimated to -10.28 ± 1.65 Tg C yr-1 , an equivalent to approximately one third of the net terrestrial ecosystems carbon sink in QTP. Our results indicate large sink for CO2 in winter is controlled by both seasonal hydrochemistry processes and lake ice absorption in saline lakes. This research also demonstrates decreasing CO2 uptake from the atmosphere by saline lakes on the QTP, which may turn carbon sinks to carbon sources with future warming.


Asunto(s)
Dióxido de Carbono , Lagos , Dióxido de Carbono/análisis , Ecosistema , Estaciones del Año , Tibet
8.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 44(3): 433-439, 2022 Jun.
Artículo en Zh | MEDLINE | ID: mdl-35791941

RESUMEN

Objective To improve the understanding and diagnostic accuracy of pulmonary mucoepidermoid carcinoma(PMEC) by analyzing the imaging and clinical characteristics.Methods The clinical and CT data of 27 cases of PMEC confirmed by histopathology in the First Medical Center of Chinese PLA General Hospital from January 2016 to December 2020 were retrospectively analyzed,including the location,size,margin,density,enhancement characteristics,accompanying signs,and pathological grade.Results The 27 cases included 6(6/27,22.2%) of large airway type,14(14/27,51.9%) of hilar type,and 7(7/27,26.9%) of peripheral type.The CT manifestations of 20 cases of large airway and hilar PMEC were soft-tissue nodules or mass with clear boundary in the lumen of the trachea and main bronchi,including 6 cases of mild enhancement,4 cases of moderate enhancement,5 cases of marked enhancement,and 5 cases of uneven enhancement.Three of the 20 cases showed calcification.The 7 cases of peripheral PMEC showed soft-tissue nodules or masses in the lungs,including 3 cases of mild enhancement,1 case of moderate enhancement,and 3 cases of marked enhancement. Obstructive pneumonia or atelectasis and bronchiectasis with mucus plug formation occurred in 16(16/27,59.3%) cases,lymph node metastasis in 9(9/27,33.3%) cases,and multiple organ metastasis in 8(8/27,29.6%) cases.Age(t=-3.132,P=0.005),enlarged lymph node (χ2=9.281,P=0.003),and distant metastasis(χ2=7.816,P=0.008) were statistically significant in the low-grade group and high-grade group. Conclusion PMEC have some unique imaging features,and recognizing these signs is conducive to the differential diagnosis and the improvement of the diagnostic accuracy.


Asunto(s)
Carcinoma Mucoepidermoide , Neoplasias Pulmonares , Carcinoma Mucoepidermoide/diagnóstico por imagen , Preescolar , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Metástasis Linfática , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos
9.
Chem Biodivers ; 18(5): e2001023, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33721383

RESUMEN

In this study, Dendrobium officinale polysaccharide (named DOPS-1) was isolated from the stems of Dendrobium officinale by hot-water extraction and purified by using Sephadex G-150 column chromatography. The structural characterization, antioxidant and cytotoxic activity were carried out. Based on the results of HPLC, GC, Congo red experiment, together with periodate oxidation, Smith degradation, SEM, FT-IR, and NMR spectral analysis, it expressed that DOPS-1 was largely composed of mannose, glucose and galacturonic acid in a molar ratio of 3.2 : 1.3 : 1. The molecular weight of DOPS-1 was 1530 kDa and the main chain was composed of (1→4)-ß-D-Glcp, (1→4)-ß-D-Manp and 2-O-acetyl-(1→4)-ß-D-Manp. The measurement results of antioxidant activity showed that DOPS-1 had the strong scavenging activities on hydroxyl radicals, DPPH radicals and superoxide radicals and the high reducing ability in vitro. Moreover, DOPS-1 was cytotoxic to all three human cancer cells of MDA-MB-231, A549 and HepG2.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Antioxidantes/farmacología , Dendrobium/química , Extractos Vegetales/farmacología , Polisacáridos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Compuestos de Bifenilo/antagonistas & inhibidores , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Picratos/antagonistas & inhibidores , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Tallos de la Planta/química , Polisacáridos/química , Polisacáridos/aislamiento & purificación
10.
BMC Genomics ; 21(1): 245, 2020 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-32188400

RESUMEN

BACKGROUND: Sheath blight (SB), caused by Rhizoctonia solani, is a common rice disease worldwide. Currently, rice cultivars with robust resistance to R. solani are still lacking. To provide theoretic basis for molecular breeding of R. solani-resistant rice cultivars, the changes of transcriptome profiles in response to R. solani infection were compared between a moderate resistant cultivar (Yanhui-888, YH) and a susceptible cultivar (Jingang-30, JG). RESULTS: In the present study, 3085 differentially express genes (DEGs) were detected between the infected leaves and the control in JG, with 2853 DEGs in YH. A total of 4091 unigenes were significantly upregulated in YH than in JG before infection, while 3192 were significantly upregulated after infection. Further analysis revealed that YH and JG showed similar molecular responses to R. solani infection, but the responses were earlier in JG than in YH. Expression levels of trans-cinnamate 4-monooxygenase (C4H), ethylene-insensitive protein 2 (EIN2), transcriptome factor WRKY33 and the KEGG pathway plant-pathogen interaction were significantly affected by R. solani infection. More importantly, these components were all over-represented in YH cultivar than in JG cultivar before and/or after infection. CONCLUSIONS: These genes possibly contribute to the higher resistance of YH to R. solani than JG and were potential target genes to molecularly breed R. solani-resistant rice cultivar.


Asunto(s)
Oryza/genética , Oryza/microbiología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/microbiología , Hojas de la Planta/genética , Hojas de la Planta/microbiología , Rhizoctonia , Transcriptoma/genética , Resistencia a la Enfermedad/genética , Regulación de la Expresión Génica de las Plantas
11.
Small ; 16(52): e2005254, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33258281

RESUMEN

The electroreduction of CO2 to value-added chemicals such as CO is a promising approach to realize carbon-neutral energy cycle, but still remains big challenge including low current density. Covalent organic frameworks (COFs) with abundant accessible active single-sites can offer a bridge between homogeneous and heterogeneous electrocatalysis, but the low electrical conductivity limits their application for CO2 electroreduction reaction (CO2 RR). Here, a 2D conductive Ni-phthalocyanine-based COF, named NiPc-COF, is synthesized by condensation of 2,3,9,10,16,17,23,24-octa-aminophthalocyaninato Ni(II) and tert-butylpyrene-tetraone for highly efficient CO2 RR. Due to its highly intrinsic conductivity and accessible active sites, the robust conductive 2D NiPc-COF nanosheets exhibit very high CO selectivity (>93%) in a wide range of the applied potentials of -0.6 to -1.1 V versus the reversible hydrogen electrode (RHE) and large partial current density of 35 mA cm-2 at -1.1 V versus RHE in aqueous solution that surpasses all the conventional COF electrocatalysts. The robust NiPc-COF that is bridged by covalent pyrazine linkage can maintain its CO2 RR activity for 10 h. This work presents the implementation of the conductive COF nanosheets for CO2 RR and provides a strategy to enhance energy conversion efficiency in electrocatalysis.

12.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 42(4): 477-484, 2020 Aug 30.
Artículo en Zh | MEDLINE | ID: mdl-32895099

RESUMEN

Objective To make a preliminary pathological classification of lung adenocarcinoma with pure ground glass nodules(pGGN)on CT by using a deep learning model. Methods CT images and pathological data of 219 patients(240 lesions in total)with pGGN on CT and pathologically confirmed adenocarcinoma were collected.According to pathological subtypes,the lesions were divided into non-invasive lung adenocarcinoma group(which included atypical adenomatous hyperplasia and adenocarcinoma in situ and micro-invasive adenocarcinoma)and invasive lung adenocarcinoma group.First,the lesions were outlined and labeled by two young radiologists,and then the labeled data were randomly divided into two datasets:the training set(80%)and the test set(20%).The prediction Results of deep learning were compared with those of two experienced radiologists by using the test dataset. Results The deep learning model achieved high performance in predicting the pathological types(non-invasive and invasive)of pGGN lung adenocarcinoma.The accuracy rate in pGGN diagnosis was 0.8330(95% CI=0.7016-0.9157)for of deep learning model,0.5000(95% CI=0.3639-0.6361)for expert 1,0.5625(95% CI=0.4227-0.6931)for expert 2,and 0.5417(95% CI=0.4029-0.6743)for both two experts.Thus,the accuracy of the deep learning model was significantly higher than those of the experienced radiologists(P=0.002).The intra-observer agreements were good(Kappa values:0.939 and 0.799,respectively).The inter-observer agreement was general(Kappa value:0.667)(P=0.000). Conclusion The deep learning model showed better performance in predicting the pathological types of pGGN lung adenocarcinoma compared with experienced radiologists.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Pulmonares , Aprendizaje Profundo , Humanos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
13.
Biochim Biophys Acta Gen Subj ; 1861(7): 1715-1728, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28300638

RESUMEN

BACKGROUND: Myocardial fibrosis contributes to cardiac dysfunction. Astaxanthin (AST), a member of the carotenoid family, is a well-known antioxidant, but its effect on and underlying mechanisms in myocardial fibrosis are poorly understood. METHODS: In vivo, myocardial fibrosis and cardiac dysfunction were induced using transverse aortic constriction (TAC). AST was administered to mice for 12weeks post-surgery. In vitro, transforming growth factor ß1 (TGF-ß1) was used to stimulate human cardiac fibroblasts (HCFs). EX-527 (6-chloro-2, 3, 4, 9-tetrahydro-1H-carbazole-1-carboxamide) and SIRT1 siRNA were used to inhibit SIRT1 in vivo and in vitro, respectively. The effects of AST on cardiac function and fibrosis were determined. SIRT1 expression and activity were measured to explore the mechanisms underlying its effects. RESULTS: AST improved cardiac function and attenuated fibrosis. Receptor activated-SMADs (R-SMADs), including SMAD2 and SMAD3, played important roles in these processes. The TAC surgery-induced increases in the expression of phosphorylated and acetylated R-SMADs were attenuated by treatment with AST, the translocation and transcriptional activity of R-SMADs were also restrained. These effects were accompanied by an increase in the expression and activity of SIRT1. Inhibiting SIRT1 attenuated the acetylation and transcriptional activity of R-SMADs, but not their phosphorylation and translocation. CONCLUSIONS: Our data demonstrate that AST improves cardiac function and attenuates fibrosis by decreasing phosphorylation and deacetylation of R-SMADs. SIRT1 contributes to AST's protective function by reducing acetylation of R-SMADs. GENERAL SIGNIFICANCE: These data suggest that AST may be useful as a preventive/therapeutic agent for cardiac dysfunction and myocardial fibrosis.


Asunto(s)
Cardiopatías/tratamiento farmacológico , Miocardio/patología , Sirtuina 1/fisiología , Acetilación , Animales , Fibrosis , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Fosforilación , Presión , Sirtuina 1/antagonistas & inhibidores , Proteína Smad2/fisiología , Proteína smad3/fisiología , Xantófilas/uso terapéutico
14.
Eur Radiol ; 27(10): 4037-4043, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28386719

RESUMEN

OBJECTIVE: To evaluate CT and histopathologic features of lung adenocarcinoma with pure ground-glass nodule (pGGN) ≤10 mm in diameter. METHODS: CT appearances of 148 patients (150 lesions) who underwent curative resection of lung adenocarcinoma with pGGN ≤10 mm (25 atypical adenomatous hyperplasias, 42 adenocarcinoma in situs, 38 minimally invasive adenocarcinomas, and 45 invasive pulmonary adenocarcinomas) were analyzed for lesion size, density, bubble-like sign, air bronchogram, vessel changes, margin, and tumour-lung interface. CT characteristics were compared among different histopathologic subtypes. Univariate and multivariate analysis were used to assess the relationship between CT characteristics of pGGN and lesion invasiveness, respectively. RESULTS: There were statistically significant differences among histopathologic subtypes in lesion size, vessel changes, and tumour-lung interface (P<0.05). Univariate analysis revealed significant differences of vessel changes, margin and tumour-lung interface between preinvasive and invasive lesions (P<0.05). Logistic regression analysis showed that the vessel changes, unsmooth margin and clear tumour-lung interface were significant predictive factors for lesion invasiveness, with odds ratios (95% CI) of 2.57 (1.17-5.62), 1.83 (1.25-2.68) and 4.25 (1.78-10.14), respectively. CONCLUSION: Invasive lesions are found in 55.3% of subcentimeter pGGNs in our cohort. Vessel changes, unsmooth margin, and clear lung-tumour interface may indicate the invasiveness of lung adenocarcinoma with subcentimeter pGGN. KEY POINTS: • Invasive lesions were found in 55.3% of lung adenocarcinomas with subcentimeter pGGNs • Lesion size, vessel changes, and tumour-lung interface showed different among histopathologic subtypes • Vessel changes, unsmooth margin and clear tumour-lung interface were predictors for lesion invasiveness.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Neoplasias Pulmonares/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adenocarcinoma/patología , Adenocarcinoma del Pulmón , Adulto , Anciano , Análisis de Varianza , Femenino , Humanos , Hiperplasia/diagnóstico por imagen , Hiperplasia/patología , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Análisis Multivariante , Invasividad Neoplásica/diagnóstico por imagen , Invasividad Neoplásica/patología , Oportunidad Relativa , Lesiones Precancerosas/diagnóstico por imagen , Lesiones Precancerosas/patología
15.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 38(2): 182-6, 2016 Apr.
Artículo en Zh | MEDLINE | ID: mdl-27181895

RESUMEN

OBJECTIVE: To investigate the correlations between vessel changes and the histopathologic subtypes of lung adenocarcinoma with pure ground-glass nodule (pGGN) on computed tomography (CT). METHODS: Totally 107 patients (116 lesions) with lung adenocarcinomas with pGGN who had undergone curative resection were included. Vessel changes included vascular convergence and/or vessel dilation or distortion within the pGGN. According to the vessel appearances within the pGGN, all patients were categorized into two groups: no change group and change group. Pearson chi-square test was used to analyze the relationships between vessel changes and histopathologic subtypes. Mann-Whitney rank test and t-test were used to identify the relationship of vessels changes with pGGN density and diameter. RESULTS: Among these 116 pGGNs, there were 21 without vessel changes and 4 with vessel changes in 25 preinvasive lesions; 14 without vessel changes and 15 with vessel changes in 29 minimally invasive adenocacinomas; 16 without vessel changes and 46 with vessel changes in 62 invasive lung adenocarcinomas. There were statistically significant differences of vessel changes (P=0.000) among histopathologic subtypes. The lesion diameter was significantly different between these two groups (P=0.000), while the lesion density showed no significant difference (P=0.826). CONCLUSION: Vessel changes may indicate the invasiveness of lung adenocarcinoma with pGGNs and are related with the lesion diameter.


Asunto(s)
Adenocarcinoma/patología , Neoplasias Pulmonares/patología , Tomografía Computarizada por Rayos X , Adenocarcinoma/clasificación , Adenocarcinoma del Pulmón , Distribución de Chi-Cuadrado , Humanos , Neoplasias Pulmonares/clasificación , Estudios Retrospectivos
16.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 38(4): 371-7, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27594146

RESUMEN

Objective To explore the risk factors of the progression of persistent pure ground-glass nodule (pGGN) and make the risk stratification for pGGN 10 mm or less in diameter. Methods From June 2008 to April 2015,100 patients (108 lesions) with persistent pGGN≤10 mm in diameter were included in this study. Patients were followed up at least 1 year using thin-section computed tomography (CT). Patients' baseline clinical data and CT characteristics of pGGN were compared between progression group (size increased or/and solid component appeared) and non-progression group. Cox regression analysis was used to assess the relationship between clinical data,CT characteristics of pGGN,and lesion progression. The risk indices of lesion progression were calculated according to the results of Cox regression analysis and the relative factors of lung adenocarcinoma in previous studies. Logistic regression analysis was used to assess the relationship between risk indices and lesion progression. The optimal cutoff value was decided on receiver operating characteristic curve of risk indices and verified for predicting lesion progression. Results Fifteen of 108 lesions showed progression. The mean follow-up duration was (1016.36±486.00) days. There were statistically significant differences of lesion size,air bronchogram,and vessel changes between progression group and non-progression group (P=0.040,P=0.003,P=0.030,respectively).Lesion density (CT value≥-542.5 HU) and air bronchogram were the risk factors of lesion progression (P=0.003,P=0.021,respectively). The optimal cutoff value of total risk indices on predicting lesion progression was 4.25,with the sensitivity of 46.7%,specificity of 89.2%,and consistency of 83.3%. Conclusions CT value ≥-542.5 HU of pGGN and air bronchogram within lesion may predict lesion progression in persistent pGGN 10 mm or less in diameter. A risk index of less than 4.25 often suggests small probability of disease progression and thus a longer follow-up interval is recommended.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Progresión de la Enfermedad , Neoplasias Pulmonares/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adenocarcinoma del Pulmón , Humanos , Curva ROC , Análisis de Regresión , Factores de Riesgo , Sensibilidad y Especificidad
17.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(2): 310-5, 2016 Feb.
Artículo en Zh | MEDLINE | ID: mdl-27209721

RESUMEN

Passive microwave remote sensing offers its all-weather work capabilities, but atmospheric influences on satellite microwave brightness temperature were different under different atmospheric conditions and environments. In order to clarify atmospheric influences on Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E), atmospheric radiation were simulated based on AMSR-E configuration under clear sky and cloudy conditions, by using radiative transfer model and atmospheric conditions data. Results showed that atmospheric water vapor was the major factor for atmospheric radiation under clear sky condition. Atmospheric transmittances were almost above 0.98 at AMSR-E's low frequencies (< 18.7 GHz) and the microwave brightness temperature changes caused by atmosphere can be ignored in clear sky condition. Atmospheric transmittances at 36.5 and 89 GHz were 0.896 and 0.756 respectively. The effects of atmospheric water vapor needed to be corrected when using microwave high-frequency channels to inverse land surface parameters in clear sky condition. But under cloud cover or cloudy conditions, cloud liquid water was the key factor to cause atmospheric radiation. When sky was covered by typical stratus cloud, atmospheric transmittances at 10.7, 18.7 and 36.5 GHz were 0.942, 0.828 and 0.605 respectively. Comparing with the clear sky condition, the down-welling atmospheric radiation caused by cloud liquid water increased up to 75.365 K at 36.5 GHz. It showed that the atmospheric correction under different clouds covered condition was the primary work to improve the accuracy of land surface parameters inversion of passive microwave remote sensing. The results also provided the basis for microwave atmospheric correction algorithm development. Finally, the atmospheric sounding data was utilized to calculate the atmospheric transmittance of Hailaer Region, Inner Mongolia province, in July 2013. The results indicated that atmospheric transmittances were close to 1 at C-band and X-band. 89 GHz was greatly influenced by water vapor and its atmospheric transmittance was not more than 0.7. Atmospheric transmittances in Hailaer Region had a relatively stable value in summer, but had about 0.1 fluctuations with the local water vapor changes.

18.
Eur Radiol ; 25(9): 2532-40, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25725775

RESUMEN

OBJECTIVES: To analyze the CT characteristics and pathological classification of early lung adenocarcinoma (T1N0M0) with pure ground-glass opacity (pGGO). METHODS: Ninety-four lesions with pGGO on CT in 88 patients with T1N0M0 lung adenocarcinoma were selected from January 2010 to December 2012. All lesions were confirmed by pathology. CT appearances were analyzed including lesion location, size, density, uniformity, shape, margin, tumour-lung interface, internal and surrounding malignant signs. Lesion size and density were compared using analysis of variance, lesion size also assessed using ROC curves. Gender of patients, lesion location and CT appearances were compared using χ²-test. RESULTS: There were no significant differences in gender, lesion location and density with histological invasiveness (P > 0.05). The ROC curve showed that the possibility of invasive lesion was 88.73% when diameter of lesion was more than 10.5 mm. There was a significant difference between lesion uniformity and histological invasiveness (P = 0.01). There were significant differences in margin, tumour-lung interface, air bronchogram with histological invasiveness ( P = 0.02,P = 0.00,P = 0.048). The correlation index of lesion size and uniformity was r = 0.45 (P = 0.00). CONCLUSIONS: The lesion size and uniformity, tumour-lung interface and the air bronchogram can help predict invasive extent of early stage lung adenocarcinoma with pGGO. KEY POINTS: • CT characteristics and pathological classification of pGGO lung adenocarcinoma smaller than 3 cm • The optimal cut-off value for discriminating preinvasive from invasive lesions was 10.5 mm • Uniformity was significant difference between histological subtypes and correlated with lesion size • Tumour margin, tumour-lung interface and air bronchogram showed different between histological types • No significant difference in gender, lesion location and density with histological subtypes.


Asunto(s)
Adenocarcinoma/diagnóstico por imagen , Detección Precoz del Cáncer/métodos , Neoplasias Pulmonares/diagnóstico por imagen , Pulmón/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adenocarcinoma del Pulmón , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Curva ROC
19.
Beijing Da Xue Xue Bao Yi Xue Ban ; 47(1): 42-6, 2015 Feb 18.
Artículo en Zh | MEDLINE | ID: mdl-25686327

RESUMEN

OBJECTIVE: To investigate the expression patterns of E-cadherin and P-cadherin in murine-tooth germs at early developmental stages. METHODS: Mandible samples of CD1 mice from embryonic day 12.5 to postnatal day 3.5 were collected. The expressions of E-cadherin and P-cadherin in murine mandibular first molar germs were detected by immunofluorescence and observed under confocal fluorescence microscope. HE staining was performed for tissue morphology. RESULTS: Both E-cadherin and P-cadherin were widely expressed in the epithelial tissues through early developmental stages. The E-cadherin expression was increased in polarizing pre-ameloblasts, whereas the P-cadherin expression declined. The expression of the P-cadherin could be detected in epithelial tissues before bud stage, and expressed in mature ameloblasts at secretory stage. CONCLUSION: The E-cadherin and P-cadherin expressed in different spatiotemporal expression patterns, indicating their individual functions during tooth development. P-cadherin might function in the secretion and mineralization of enamel.


Asunto(s)
Cadherinas/metabolismo , Odontogénesis , Germen Dentario/metabolismo , Ameloblastos/metabolismo , Animales , Esmalte Dental , Expresión Génica , Ratones , Diente Molar
20.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 37(2): 163-70, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25936704

RESUMEN

OBJECTIVE: To discuss the correlation of pathologic subtypes and immunohistochemical implication with CT features of lung adenocarcinoma 1 cm or less in diameter with focal ground-glass opacity (fGGO). METHODS: CT appearances of 59 patients who underwent curative resection of lung adenocarcinoma ≤ 1 cm with fGGO were analyzed in terms of lesion location, size, density, shape (round, oval, polygonal, irregular), margin (smooth, lobular, spiculated, lobular and spiculated), bubble-like sign, air bronchogram, pleural tag, and tumor-lung interface. Histopathologic subtypes were classified according to International Association for the Study of Lung Cancer/ American Thoracic Society/European Respiratory Society classification of lung adenocarcinoma. Common molecular markers in immunohistochemical study included human epidermal growth factor receptor (HER)-1,HER-2,Ki-67, vascular endothelial growth factor (VEGF) and DNA topoisomerase 2Α.Patients' age and lesions' size and density were compared with pathologic subtypes using analysis of variance or nonparametric Wilcoxon tests. Patients' gender, lesion location, shape and margin, bubble-like sign, air bronchogram, pleural tag, and tumor-lung interface were compared with histopathologic subtypes and immunohistochemical implication using ψ² test or Fisher's exact test. RESULTS: The patients' gender, age, lesion location, shape, air bronchogram, pleural tag, and tumor-lung interface were not significantly different among different histopathologic subtypes (P=0.194, 0.126, 0.609, 0.678, 0.091, 0.374, and 0.339, respectively), whereas the lesion size,density,bubble-like sign, and margin showed significant differences (P=0.028, 0.002, 0.003, 0.046, respectively). The expression of Ki-67 significantly differed among nodules with different shapes(P=0.015). Statistically significant difference also existed between tumor-lung interface and HER-1 expression (P=0.019) and between bubble sign and HER-2 expression (P=0.049). CONCLUSIONS: Of lung adenocarcinoma ≤ 1 cm with fGGO,bubble-like sign occurs more frequently in invasive pulmonary adenocarcinoma and less frequently in atypical adenomatous hyperplasia. In addition, preinvasive lesions (atypical adenomatous hyperplasia and adenocarcinoma in situ) more frequently demonstrates smooth margin,while invasive lesions (minimally invasive adenocarcinoma and invasive pulmonary adenocarcinoma) more frequently demonstrates lobular and spiculated margin. Some CT features are associated with immunohistochemical implication of lung adenocarcinoma ≤ 1 cm with fGGO.


Asunto(s)
Adenocarcinoma , Neoplasias Pulmonares , Adenocarcinoma del Pulmón , Humanos , Hiperplasia , Pulmón , Factor A de Crecimiento Endotelial Vascular
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