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1.
Front Neurol ; 15: 1376216, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38606277

RESUMEN

Objectives: This study aimed to investigate the efficacy of using a newly formulated magnesium-rich artificial cerebrospinal fluid (MACSF) as an alternative to normal saline (NS) for intraoperative irrigation during aneurysm clipping in improving the prognosis of patients with Aneurysmal subarachnoid hemorrhage (aSAH). Methods: Patients with aSAH who underwent intraoperative irrigation with MACSF or NS during the clipping in the First Affiliated Hospital of Xi 'an Jiaotong University from March 2019 to March 2022 were selected as MACSF group and NS group, respectively. The primary prognostic indicators were the incidence of favorable outcomes (mRS 0-2). The secondary outcome measures included cerebral vasospasm (CVS), mortality, total hospital stay, and intensive care unit (ICU) stay. Safety was evaluated based on the occurrence rates of hypermagnesemia, meningitis, and hydrocephalus. Results: Overall, 34 and 37 patients were enrolled in the MACSF and NS groups, respectively. At 90 days after aSAH onset, the proportion of favorable prognosis in the MACSF group was significantly higher than that in the NS group (p = 0.035). The incidence of CVS within 14 days after surgery was significantly lower in the MACSF group than that in the NS group (p = 0.026). The mortality rate in the MACSF group was significantly lower than in the NS group (p = 0.048). The median lengths of hospital stay (p = 0.008) and ICU stay (p = 0.018) were significantly shorter in the MACSF group than in the NS group. No significant differences were observed in safety measures. Conclusion: Using MACSF as an irrigation fluid for aneurysm clipping can significantly improve the 90-day prognosis of patients with aSAH, which may be related to the reduced incidence of CVS. Clinical trial registration: https://www.clinicaltrials.gov, identifier NCT04358445.

2.
Environ Sci Pollut Res Int ; 31(7): 10887-10895, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38214859

RESUMEN

Dehydration with a plate and frame filter press is a common method for treating dredged silt from rivers and lakes. The silt is often conditioned by the addition of solidifying materials before plate and frame press filtration and, therefore, is subjected to the coupling effect of solidification and consolidation. In this study, consolidation tests of the silt with cement were carried out and compared with the silt after only solidification or only consolidation in terms of moisture content, unconfined compressive strength, and leaching concentration. The test results showed that the moisture content of the silt can be reduced to less than 60% under the coupling action of solidification and consolidation, which was 22% and 4% lower than with solidification only or consolidation only, respectively. The effect of consolidation improved the solidification process; the unconfined compressive strength increased rapidly in the early stage of curing and was 30-150% higher than that of solidified silt. The coupling effects of solidification and consolidation on the leaching concentrations of Ni and Cr in silt were the most significant, and the lowest leaching concentrations were 60% and 90% lower than those of solidified only and consolidated only silt, respectively.


Asunto(s)
Metales Pesados , Metales Pesados/análisis , Fuerza Compresiva , Filtración , Lagos
3.
Front Plant Sci ; 14: 1070674, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37324697

RESUMEN

Introduction: In natural systems, diverse plant communities tend to prevent a single species from dominating. Similarly, management of invasive alien plants may be achieved through various combinations of competing species. Methods: We used a de Wit replacement series to compare different combinations of sweet potato (Ipomoea batatas (L.) Lam), hyacinth bean (Lablab purpureus (L.) Sweet) and mile-a-minute (Mikania micrantha Kunth) through measures of photosynthesis, plant growth, nutrient levels in plant tissue and soil, and competitive ability. Results: Cultured alone sweet potato and hyacinth beans exhibited higher total biomass, leafstalk length, and leaf area than mile-a-minute. In mixed culture, either sweet potato or hyacinth bean or both together significantly suppressed the mile-a-minute parameters, i.e., plant height, branch, leaf, adventitious root, and biomass (P<0.05). Based on a significantly lower than 1.0 relative yield of the three plant species in mixed culture, we showed intraspecific competition to be less than interspecific competition. Calculated indices (relative yield, relative yield total, competitive balance index, and change in contribution) demonstrated a higher competitive ability and higher influence of either crop compared to mile-a-minute. The presence of sweet potato and hyacinth bean, especially with both species in combination, significantly reduced (P<0.05) mile-a-minute's net photosynthetic rate (Pn), antioxidant enzyme activities (superoxide dismutase, peroxidase, catalase, and malondialdehyde), chlorophyll content, and nutrient content (N, P, and K). In soil with mile-a-minute in monoculture soil organic matter, total and available N, total and available K, and available P were significantly greater (P<0.05) than in soil with sweet potato grown in monoculture, but less than in soil with hyacinth bean grown in monoculture soil. Nutrient soil content was comparatively reduced for plant mixtures. Plant height, leaf, biomass, Pn, antioxidant enzyme activities, and plant and soil nutrient contents of sweet potato and hyacinth bean tended to be much greater when grown with two crops compared to in mixture with just sweet potato or hyacinth bean. Discussion: Our results suggest that the competitive abilities of both sweet potato and hyacinth bean were greater than that of mile-a-minute, and also that mile-a-minute suppression was significantly improved via a combination of the two crops compared to either sweet potato or hyacinth bean alone.

4.
Artículo en Inglés | MEDLINE | ID: mdl-36900964

RESUMEN

The essence of post-disaster reconstruction is the restoration and rebirth of the affected areas. The earthquake hitting Jiuzhaigou was the first earthquake that had its epicenter in the World Natural Heritage located in China. Ecological restoration and landscape reconstruction are essential for the sustainable development of tourism. This study uses high-resolution remote sensing images to monitor and evaluate the post-disaster restoration and reconstruction process of the leading lakes in Jiuzhaigou. It was found that the lake water quality, vegetation, and road facilities have undergone moderate reconstruction. However, the restoration and reconstruction still faced severe challenges. The ecological environment's stability and balance are prerequisites for the sustainable development of the World Natural Heritage sites. This paper combines the "Build Back Better" concept that advocates risk reduction, scenic spot restoration, and efficient implementation to ensure Jiuzhaigou's restoration and sustainable development. It comes up with specific measures for the resilience development of Jiuzhaigou from the eight principles of overall planning, structural resilience, disaster prevention and mitigation, landscape facilities, social psychology, management mechanisms, policies and regulations, and monitoring and evaluation to provide a reference for the sustainable development of tourism.


Asunto(s)
Desastres , Terremotos , Lagos , Desarrollo Sostenible , Turismo , China
5.
Int J Infect Dis ; 126: 136-144, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36343866

RESUMEN

OBJECTIVES: Rabies is an acute lethal infectious disease caused by a lyssavirus infection. In 2018, the World Health Organization proposed a global strategic plan to end human rabies deaths by 2030. However, systematic studies on the global rabies disease burden and epidemiological trends are scarce. METHODS: We extracted the disease burden and epidemiological data of rabies worldwide in the preceding 30 years from the Global Burden of Disease Study 2019 and performed a comprehensive analysis. RESULTS: In 2019, the incident cases of rabies worldwide were 14,075.51 (95% uncertainty interval: 6124.33-21,618.11), and the number of deaths was 13,743.44 (95% uncertainty interval: 6019.13-17,938.53), both of which were lower than that in 1990. With the improvement of the sociodemographic index, the incident cases, the number of deaths, age-standardized incidence rate, age-standardized incidence death rate, and disability-adjusted life years of rabies all showed downward trends. Adolescents and adults aged <50 years represented the majority of rabies cases worldwide. CONCLUSION: The global disease burden of rabies has declined over the past 30 years. Furthermore, the disease burden of rabies was closely related to the sociodemographic index level.


Asunto(s)
Carga Global de Enfermedades , Rabia , Adulto , Adolescente , Humanos , Rabia/epidemiología , Incidencia , Salud Global , Organización Mundial de la Salud , Años de Vida Ajustados por Calidad de Vida
6.
Jpn J Radiol ; 40(9): 903-913, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35507139

RESUMEN

PURPOSE: To evaluate the potential of intravoxel incoherent motion (IVIM) and apparent diffusion coefficient (ADC) in the prediction of tumor grade, lymph node metastasis and pleural invasion of non-small cell lung cancer (NSCLC) before surgery. MATERIALS AND METHODS: 65 patients diagnosed with NSCLC by surgery were enrolled. IVIM-DWI (10 b-values, 0-1000 s/mm2) was performed before surgery. The mean and minimum ADC (ADCmean, ADCmin) and IVIM parameters D, D* and f were independently measured and calculated by 2 radiologists by drawing regions of interest (ROIs) including the solid component of the whole tumor. Intraclass correlation coefficients (ICCs) were analysed. Spearman analysis was used to determine the correlation between IVIM parameters and tumor differentiation. Independent sample t-tests (normal distribution) or Mann-Whitney U tests (non-normal distribution) were used to compare the differences between the parameters in moderately-well and poorly differentiated groups, with and without lymph node metastasis and pleural invasion groups. Receiver operating characteristic (ROC) curves were generated. RESULTS: The ADCmean, ADCmin, D and f values were negatively correlated with the pathological grades of tumor (P < 0.05). The ADCmean and D values of patients with poor differentiation and lymph node metastasis were significantly lower than that of patients with moderately-well differentiation and without lymph node metastasis (P < 0.001-0.012). The D value was significantly lower and f value was significantly higher among patients with pleural invasion than those without (P = 0.033 and < 0.001). ROC analysis showed that the area under the ROC curve (AUC) was larger for D in predicting the degree of differentiation (0.832) and lymph node metastasis (0.806), and higher for f in predicting pleural invasion (0.832). CONCLUSIONS: IVIM is useful for predicting the tumor differentiation, lymph node metastasis and pleural invasion in NSCLC patients before surgery.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/cirugía , Imagen de Difusión por Resonancia Magnética/métodos , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/cirugía , Metástasis Linfática/diagnóstico por imagen , Movimiento (Física)
7.
Front Plant Sci ; 13: 823947, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35498714

RESUMEN

Sweet potato [Ipomoea batatas (L.) Lam] is grown as important cash and food crop worldwide and has been shown to exhibit allelopathic effects on other plants. However, its metabolome has not been studied extensively, particularly with respect to the production of phytotoxic bioactive secondary products. In this study, the chemical composition of petroleum ether extract of sweet potato was characterized, and the morphological and physiological effects of some individual components against four invasive alien weeds Bidens pilosa L., Galinsoga parviflora Cav., Lolium multiflorum Lam., and Phalaris minor Retz. were determined. Twenty-one components were identified by GS-MS, constituting 96.08% of petroleum ether extract in sweet potato. The major components were palmitic acid (PA) (17.48%), ethyl linoleate (EL) (13.19%), linoleic acid (LA) (12.55%), ethyl palmitate (EP) (11.77%), ethyl linolenate (ELL) (8.29%) oleic acid (5.82%), ethyl stearate (4.19%), and 3-methylphenol acetate (3.19%). The five most abundant compounds exhibited strong inhibition activity against the four invasive weeds tested. The highest inhibition rates were seen for LA, followed by PA and EP, respectively. Catalase (CAT), malondialdehyde (MDA), and peroxidase (POD) content of L. multiflorum were increased by the three allelochemicals, i.e., LA, PA and EP, but superoxide dismutase (SOD), chlorophyll-a and chlorophyll-b levels declined. Overall, the combined impact of all five compounds could be quite effective in suppressing the invasive weeds of concern.

8.
J Comput Assist Tomogr ; 46(3): 406-412, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35405718

RESUMEN

OBJECTIVE: We aimed to prospectively investigate intravoxel incoherent motion parameters to predict the response to chemotherapy in locally advanced non-small cell lung cancer (NSCLC) patients. METHODS: From July 2016 to March 2018, 30 advanced NSCLC patients were enrolled and underwent chest intravoxel incoherent motion-diffusion-weighted imaging at Siemens 3T magnetic resonance imaging before and at the end of the first cycle of chemotherapy. Regions of interest were drawn including the whole tumor volume to derive the apparent diffusion coefficient value, D, D*, and f, respectively. Time-dependent receiver operating characteristic curves were generated to evaluate the cutoff values of continuous variables. A Cox proportional hazards model was used to assess the independent predictors of progression-free survival (PFS) and overall survival (OS). Kaplan-Meier curves and log-rank test were generated. RESULTS: Among the 30 patients, 28 cases (93.3%) died and 2 cases (6.7%) survived till the closeout date. Univariate Cox regression analyses revealed that the significant predictors of PFS and OS were the tumor size reduction rate, the change rates of D and apparent diffusion coefficient values, and the D value before therapy (PFS: P = 0.015, hazard ratio [HR] = 2.841; P < 0.001, HR = 5.840; P = 0.044, HR = 2.457; and P = 0.027, HR = 2.715; OS: P = 0.008, HR = 2.987; P < 0.001, HR = 4.357; P = 0.006, HR = 3.313; and P = 0.013, HR = 2.941, respectively). Multivariate Cox regression analysis suggested that △D% was identified as independent predictors of both PFS and OS (P = 0.003, HR = 9.200 and P = 0.016, HR = 4.617). In addition, the cutoff value of △D% was 21.06% calculated by receiver operating characteristic curve analysis. In the Kaplan-Meier analysis, the PFS and OS were significantly greater in the group of patients with △D% larger than 21.06% (log-rank test, χ2 = 16.453, P < 0.001; χ2 = 13.952, P < 0.001). CONCLUSIONS: Intravoxel incoherent motion-diffusion-weighted imaging was preferred for predicting the prognosis of advanced NSCLC patients treated with chemotherapy. A D increase more than 21.06% at 1 month was associated with a lower rate of disease progression and death.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Imagen de Difusión por Resonancia Magnética/métodos , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/tratamiento farmacológico , Imagen por Resonancia Magnética , Movimiento (Física)
9.
Front Cardiovasc Med ; 9: 1062258, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36588558

RESUMEN

Objective: Myocardial fibrosis leads to systolic dysfunction in hypertrophic cardiomyopathy (HCM) patients. This study aims to investigate the relationship between cardiac magnetic resonance mechanical parameters for evaluating the left ventricular function in HCM with preserved left ventricular ejection fraction (LVEF ≥50%) and the association between myocardial fibrosis defined by late gadolinium enhancement (LGE). Methods: This study was a retrospective analysis of CMR images of 93 patients with HCM with preserved ejection fraction (HCMpEF) and 96 controls diagnosed by cardiac magnetic resonance (CMR) at our hospital from July 2019 to January 2022. The myocardial contraction fraction (MCF) was calculated, and myocardial mechanical parameters, including global myocardial longitudinal strain (GLS), circumferential strain (GLS), and myocardial strain (GLS), were obtained by tissue tracking and LGE quantitative modules of dedicated software, respectively. The correlation between myocardial strain and LGE was analyzed, and a multivariate logistic regression model was developed to discuss the risk predictors of LGE. Results: Compared to the control group, the left ventricular mechanical parameters GLS (-13.90 ± 3.80% versus -18.20 ± 2.10%, p < 0.001), GCS (-16.62 ± 3.50% versus -18.4 ± 2.69%, p < 0.001), GRS (28.99 ± 10.38% versus 33.02 ± 6.25%, p < 0.01), and MCF (64 ± 16% versus 99 ± 18%, p < 0.001) were found significantly lower in HCM group. Moreover, even in LGE-negative HCM patients, GLS (-16.3 ± 3.9%) and MCF (78 ± 19%) were significantly lower compared to the control group. Left ventricular GLS [OR = 1.61, (1.29, 2.02), p = 0.001] and MCF [OR = 0.90, (0.86, 0.94), p = 0.001] independently predicted myocardial late gadolinium enhancement (LGE). Conclusion: In participants of HCM with preserved ejection fraction, the early onset of reduced left ventricular GLS and MCF in patients with HCMpEF may provide new evidence for evaluating impaired myocardial systolic function. The reduction of myocardial mechanical indexes may reflect the presence and extent of myocardial fibrosis, and the more significant the reduction, the more severe the myocardial fibrosis; GLS and MCF may be ideal predictors for LGE.

10.
J Magn Reson Imaging ; 54(5): 1529-1540, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34291852

RESUMEN

BACKGROUND: T1 mapping can potentially quantitatively assess the intrinsic properties of tumors. B1 correction can reduce the magnetic field inhomogeneity. PURPOSE: To assess the repeatability and reproducibility of B1 -corrected T1 mapping for lung cancer and the ability to identify pathological types. STUDY TYPE: Prospective reproducibility study. POPULATION: Sixty lung cancer patients (22 with emphysema) with a total of 60 lesions (adenocarcinoma [n = 23], squamous cell carcinoma [n = 19], and small-cell lung cancer [SCLC] [n = 18]). FIELD STRENGTH/SEQUENCE: A 3 T/B1 -corrected 3D variable flip angle T1 mapping and free-breathing diffusion-weighted imaging. ASSESSMENT: Intraobserver, interobserver, and test-retest reproducibility of minimum, maximum, mean, and SD of lung tumor T1 values were assessed. The correlation between mean T1 and apparent diffusion coefficient (ADC) and differences between different histological types of lung cancer were evaluated. STATISTICAL TESTS: Intraclass correlation coefficients (ICCs), within-subject coefficients of variation (WCVs), Bland-Altman plots, Pearson's correlation coefficient (r), and analysis of variance (ANOVA). A P value <0.05 was considered to be statistically significant. RESULTS: No significant differences were found in minimum, maximum, mean, and SD T1 values for repeated measurements (intraobserver and interobserver) and repeated examinations (P = 0.103-0.979). All parameters showed good intraobserver, interobserver and test-retest reproducibility (ICC, 0.780-0.978), except the maximum T1 value (ICC, 0.645-0.922). The mean T1 exhibited the best reproducibility and repeatability, with an average difference <6% for repeated measurements, <8% for repeated scans in lung cancer patients, and<10% for repeated scans in those with emphysema. The mean T1 correlated moderately with ADC (r = -0.580, -0.516, and -0.511 for observers A, B, and C). Both mean T1 and mean ADC were significantly different in SCLC patients compared with those in adenocarcinoma and squamous cell carcinoma patients. DATA CONCLUSION: The mean T1 from B1 -corrected T1 mapping is a repeatable parameter with the potential to identify histological types of lung cancer and thus may be a promising imaging biomarker for characterizing lung cancer. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 2.


Asunto(s)
Imagen de Difusión por Resonancia Magnética , Neoplasias Pulmonares , Biomarcadores , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Estudios Prospectivos , Reproducibilidad de los Resultados
11.
Physiol Plant ; 173(3): 911-919, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34164817

RESUMEN

Mikania micrantha Kunth is a serious invasive alien plant characterized by the formation of an adventitious root system in its prostrate growth form. Unlike the initial roots from seed germination, adventitious roots gradually appear above the stem and branch nodes. Little is known about adventitious roots play on plant growth and population expansion of M. micrantha. We hypothesized that adventitious roots provide an advantage for plant growth and nutrient availability. To test this hypothesis, plant growth, physiology, and nutrition characteristics of M. micrantha were measured under four soil surface conditions allowing various plant parts to touch the soil to stimulate variable adventitious root formation. The results showed that the biomass, stem length, branch number, and adventitious root biomass of M. micrantha were significantly increased (P < 0.05) with increasing nodes bearing adventitious roots. As the number of nodes with adventitious roots increased, the net photosynthetic rate, antioxidant enzyme activities like superoxide dismutase, catalase, peroxidase, and malondialdehyde, chlorophyll content, and plant nutrient contents (N, P, and K) of M. micrantha were increased (P < 0.05), with higher values in main stem leaves than in those of branch leaves. The concentrations of soil organic matter, total N, total P, total K, available N, available P, and available K were greater (P < 0.05) in initial soil (CK) than in treatment soil (with M. micrantha) and were significantly reduced by adventitious roots. Our study was the first to show that plant growth, physiology and nutrition status of M. micrantha were strongly promoted by adventitious roots in the prostrate growth form.


Asunto(s)
Mikania , Biomasa , Fotosíntesis , Hojas de la Planta , Raíces de Plantas , Suelo
12.
BMC Ecol Evol ; 21(1): 85, 2021 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-33993871

RESUMEN

BACKGROUND: An ecological approach for managing biological invasions in agroecosystems is the selection of alternative crop species to manage the infestation of invasive alien plants through competition. In the current study, plant growth, photosynthesis, and competitive ability of the crop Helianthus tuberosus L. (Jerusalem artichoke) and the invasive alien plant Ageratina adenophora (Spreng.) R. M. King and H. Rob were compared under varying shade levels by utilizing a de Wit replacement series method. We hypothesized that H. tuberosus had higher competitive ability than A. adenophora even under shaded conditions. RESULTS: The results showed the main stem, leafstalk length, leaf area, underground biomass, and aboveground biomass of A. adenophora were significantly lower compared to H. tuberosus in monoculture although A. adenophora had a greater number of branches that were longer on average. Under full sunlight, the total shoot length (stem + branch length), main stem length and branch length of A. adenophora were significantly suppressed (P < 0.05) by increasing proportions of H. tuberosus, and the same morphological variables of H. tuberosus were significantly higher with decreasing proportions of H. tuberosus. With increasing shade rates and plant ratios, the plant height, branch, leaf, and biomass of both plants were significantly suppressed, but to a greater degree in the case of A. adenophora. The net photosynthetic rate (Pn) of H. tuberosus and A. adenophora increased gradually from July to September, then decreased in October. The Pn of H. tuberosus was consistently higher than that of A. adenophora. Although the Pn for both species was significantly reduced with increasing shade rates and plant ratios, A. adenophora experienced greater inhibition than H. tuberosus. The relative yield (RY) of A. adenophora was significantly less than 1.0 (P < 0.05) in mixed culture under all shade levels, indicating that the intraspecific competition was less than interspecific competition. The RY of H. tuberosus was significantly less than 1.0 under 40-60% shade and greater than 1.0 (P < 0.05) under 0-20% shade in mixed culture, respectively, showing that intraspecific competition was higher than interspecific competition under low shade, but the converse was true under high shade. The relative yield total (RYT) of A. adenophora and H. tuberosus was less than 1.0 in mixed culture, indicating that there was competition between the two plants. The fact that the competitive balance (CB) index of H. tuberosus was greater than zero demonstrated a higher competitive ability than A. adenophora even at the highest shade level (60%). CONCLUSIONS: Our results suggest that H. tuberosus is a promising replacement control candidate for managing infestations of A. adenophora, and could be widely used in various habitats where A. adenophora invades.


Asunto(s)
Ageratina , Helianthus , Biomasa , Fotosíntesis , Hojas de la Planta
13.
Phys Rev Lett ; 125(15): 157402, 2020 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-33095598

RESUMEN

In many atomically thin materials, their optical absorption is dominated by excitonic transitions. It was recently found that optical selection rules in these materials are influenced by the band topology near the valleys. We propose that gate-controlled band ordering in a single atomic monolayer, through changes in the valley winding number and excitonic transitions, can be probed in helicity-resolved absorption and photoluminescence. This predicted tunable band topology is confirmed by combining an effective Hamiltonian and a Bethe-Salpeter equation for an accurate description of excitons, with first-principles calculations suggesting its realization in Sb-based monolayers.

14.
Br J Radiol ; 93(1110): 20190400, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32163295

RESUMEN

OBJECTIVES: The objective is to compare the efficacy of diffusion-weighted imaging (DWI) parameters of mean and minimum apparent diffusion coefficient (ADCmean and ADCmin) and intravoxel incoherent motion (IVIM) in the differentiation of benign and malignant lung nodules and masses. METHODS: Lung lesions measured larger than 1.5 cm on CT were included between August 2015 and September 2018. DWI (10 b-values, 0-1000 s/mm2) scans were performed, and the data were post-processed to derive the ADCmean, ADCmin and IVIM parameters of true diffusion coefficient (D), pseudodiffusion coefficient (D*) and perfusion fraction (f). An independent sample t-test or Mann-Whitney U test was used to compare benign and malignant parameters. Receiver operating characteristic curves were generated and a Z test was used. RESULTS: 121 patients were finally enrolled, each with one lesion. Examined 121 lesions were malignant in 88 (72.7%) and benign in 33 (27.3%). The ADCmean of malignant pulmonary nodules was significantly lower than that of benign pulmonary nodules (t = 3.156, p = 0.006), whereas the other parameters revealed no significant differences (p = 0.162-0.690). Receiver operating characteristic curve analysis revealed that an ADCmean threshold value of 1.43 × 10-3 mm2/s yielded 88.57% sensitivity and 64.29% specificity. While for lung masses, the ADCmean, ADCmin, D and D* values in malignant pulmonary masses were significantly lower (P﹤0.001-0.011). Among them, the D value exhibited the best diagnostic performance when the threshold of D was 1.23 × 10-3mm2/s, which yielded a sensitivity of 90.57% and a specificity of 89.47% (Z = 2.230, 3.958, 2.877 and p = 0.026, ﹤0.001 and 0.004, respectively). CONCLUSION: ADC is the most robust parameter to differentiate benign and malignant lung nodules, whereas D is the most robust parameter to differentiate benign and malignant lung masses. ADVANCES IN KNOWLEDGE: This is the first study to compare all the quantitative parameters of DWI and IVIM mentioned in the literatures for assessing lung lesions; Second, we divided the lesions into lung nodules and lung masses with the size of 3 cm as the boundary.


Asunto(s)
Imagen de Difusión por Resonancia Magnética/métodos , Neoplasias Pulmonares/diagnóstico por imagen , Nódulos Pulmonares Múltiples/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Aumento de la Imagen/métodos , Enfermedades Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Nódulos Pulmonares Múltiples/patología , Variaciones Dependientes del Observador , Curva ROC , Sensibilidad y Especificidad , Estadísticas no Paramétricas , Carga Tumoral , Adulto Joven
15.
Neurol Res ; 41(11): 1015-1023, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31559927

RESUMEN

Objectives Cerebral vasospasm after subarachnoid haemorrhage (SAH) is associated with cerebrovascular contractile receptor upregulation resulted from haemolysis in the subarachnoid space. This study developed a new magnesium-rich artificial cerebrospinal fluid (MACSF) formula and investigated its effects on receptor-mediated contraction in rat basilar arteries. Methods Clear and haemorrhagic cerebrospinal fluid (CSF) were collected from patients with hydrocephalus or SAH. MACSF was freshly prepared using clinical intravenous injections. Rat basilar arteries were segmented and incubated with clear CSF, haemorrhagic CSF or MACSF. The contractile responses were studied by myograph. The messenger ribonucleic acid (mRNA) and protein expression of 5-hydroxytryptamine 1B (5-HT1B), endothelin subtype B (ETB) and endothelin subtype A (ETA) receptors were evaluated by real-time polymerase chain reaction (PCR) and Western blot analyses. Results Haemorrhagic CSF exposure shifted the contractile curves induced by 5-hydroxytryptamine (5-HT), sarafotoxins 6c (S6c) and endothelin-1 (ET-1) leftward with increased maximal contraction values. Furthermore, mRNA and protein expression were markedly elevated for 5-HT1B, ETB and ETA receptors on arteries exposed to haemorrhagic CSF. However, the contractile responses to 5-HT, S6c or ET-1 and expression of 5-HT1B, ETB and ETA receptors in rat cerebral arteries exposed to MACSF remained unaffected compared to those exposed to clear CSF. Besides, unlike normal saline which can inactive in-vitro vessels, MACSF can maintain their physiological activity. Conclusion Haemorrhagic CSF induces upregulation of 5-HT1B, ETB and ETA receptors in rat cerebral arteries. However, MACSF can maintain in-vitro rat basilar arteries in good physiological activity and normal expression of contractile 5-HT and ET receptors.


Asunto(s)
Arterias Cerebrales/efectos de los fármacos , Magnesio/metabolismo , Receptores de Endotelina/metabolismo , Serotonina/metabolismo , Hemorragia Subaracnoidea/tratamiento farmacológico , Animales , Femenino , Masculino , Contracción Muscular/efectos de los fármacos , Hemorragia Subaracnoidea/inducido químicamente , Hemorragia Subaracnoidea/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Vasoespasmo Intracraneal/metabolismo
16.
Bioresour Technol ; 286: 121392, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31075663

RESUMEN

The sugarcane bagasse (SCB) was pretreated by the sequential Fenton oxidation and sulfomethylation pretreatment (FSP) for reducing the lignin inhibition in enzymatic saccharification. The FSP showed the delignification of 67.76% and the glucan retention in pretreated solid of 97.81%. Compared with sulfomethylation pretreated SCB (SP-SCB), the lignin surface coverage and surface hydrophobicity of FSP-SCB decreased by 1.84 and 4.84 times, respectively, led to enzymatic accessibility increased by 20%. Using the cellulase loading of 20 FPU/g glucan, the 72 h yields of glucose and xylose were 76.24% and 64.83%, respectively, which was 1.3-2.0 times higher than that of sulfomethylation treated SCB alone. Fenton oxidative reaction as a pre-step will help sulfomethyl group to easily and more introduce on aromatic ring, thereby accelerating the delignification.


Asunto(s)
Celulasa , Saccharum , Celulosa , Hidrólisis , Lignina
17.
Int J Biol Macromol ; 133: 964-970, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31004636

RESUMEN

Porous grafted copolymer with excellent thermal stability and swelling capacity was synthesized from water soluble Prunus cerasifera gum polysaccharide (PG) and acrylamide (AM). The monosaccharide compositions and the structure of Prunus cerasifera tree gum were detected by a high-performance anion exchange chromatography (HPAEC) system and 1H NMR and 13C NMR, and the obtained PG-AM copolymer was characterized by Fourier transform infrared (FT-IR), scanning electron microscope (SEM), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), respectively. The results indicated that the water soluble polysaccharides obtained from Prunus cerasifera tree gum were mainly composed of l-arabinose (39.78%) and d-galactose (40.59%) with minor amount of xylose, mannose and uronic acids. The maximum percent and the grafting efficiency of grafting acrylamide (AM) onto PG to form PG-AM were obtained by copolymerization between polysaccharide and 3 times (weight) acrylamide with 3 mmol/L potassium persulfate initiator at 50 °C for 1 h. In addition, lots of isolated and conjoint pores were observed in the prepared PG-AM materials, with a diameters distribution between 2 and 10 µm. Compared with PG, the synthesized copolymer PG-AM showed an excellent performance in thermal stability and swelling capacity. The detailed structural characteristic together with excellent thermal stability and swelling properties will benefit efficient utilization of the synthesized copolymer as a precursor for preparation of large-scale environmentally friendly advanced materials with various potential applications.


Asunto(s)
Gomas de Plantas/química , Polimerizacion , Polisacáridos/química , Polisacáridos/síntesis química , Prunus domestica/química , Acrilamida/química , Técnicas de Química Sintética , Monosacáridos/análisis , Porosidad , Temperatura , Ácidos Urónicos/análisis
18.
Nature ; 568(7751): 212-215, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30944471

RESUMEN

Lasers have both ubiquitous applications and roles as model systems in which non-equilibrium and cooperative phenomena can be elucidated1. The introduction of novel concepts in laser operation thus has potential to lead to both new applications and fundamental insights2. Spintronics3, in which both the spin and the charge of the electron are used, has led to the development of spin-lasers, in which charge-carrier spin and photon spin are exploited. Here we show experimentally that the coupling between carrier spin and light polarization in common semiconductor lasers can enable room-temperature modulation frequencies above 200 gigahertz, exceeding by nearly an order of magnitude the best conventional semiconductor lasers. Surprisingly, this ultrafast operation of the resultant spin-laser relies on a short carrier spin relaxation time and a large anisotropy of the refractive index, both of which are commonly viewed as detrimental in spintronics3 and conventional lasers4. Our results overcome the key speed limitations of conventional directly modulated lasers and offer a prospect for the next generation of low-energy ultrafast optical communication.

19.
Oncol Lett ; 17(2): 2516-2522, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30719120

RESUMEN

Being biomarkers that reflect host nutritional and immune status, prognostic nutritional index (PNI) and neutrophil/lymphocyte ratio (NLR) have been identified to be independent prognostic factors in various malignancies. The aim of the present study was to determine the predictive value of these parameters for the prognosis of patients with glioma. Hematological and clinicopathological data were retrospectively analyzed from 128 patients with glioma who underwent brain tumor resection between January 2008 and December 2012. Receiver operating characteristic (ROC) analysis was used to determine the optimal cut-offs for PNI and NLR. Kaplan-Meier survival analysis, and univariate and multivariate analyses based on Cox proportional hazards regression model were used to determine whether NLR and PNI were associated with the prognosis of patients with glioma. R software was used to develop nomograms with all the independent prognostic factors included. Kaplan-Meier analysis followed by log-rank tests indicated that NLR ≥2.8 and PNI <45 were significantly associated with decreased overall survival time. The subsequent multivariate analysis indicated that age ≥50 years [hazard ratio (HR), 2.328; 95% confidence interval (CI), 1.386-3.908; P<0.001], high-grade glioma (HR, 3.088; 95% CI, 1.893-5.037; P<0.001), gross total resection (HR, 0.606; 95% CI, 0.380-0.965; P=0.035) and NLR ≥2.8 (HR, 2.037; 95% CI, 1.264-3.281; P=0.003) were independent prognostic factors. The results of the present study indicated that high NLR was an independent risk factor for overall survival rates in patients with glioma, which indicated its value in improving the current prognostic model.

20.
Artículo en Inglés | MEDLINE | ID: mdl-30609854

RESUMEN

The high-speed economic growth of mega city-regions in China has been characterized by rapid urbanization accompanied by a series of environmental issues ranging from widespread soil contamination to groundwater depletion. This article begins with an analysis of the interaction between urbanization and the ecological system and reviews existing frameworks for analyzing urban and ecological systems. By taking the Beijing-Tianjin-Hebei region as an example, the article introduces a conceptual framework to analyze mega city-regions and forecast possible interactions between urbanization and eco-environment by applying simulation model. The proposed framework and its components can provide guidance to identify the impacts of urbanization and external forces such as globalization on eco-environment by integrating the internal and external factors, synthesize the complex components of mega city-regions in databases, understand and diagnose the casual relationship between urban policies and ecological consequences.


Asunto(s)
Ecosistema , Urbanización , China , Ciudades , Desarrollo Económico , Contaminación Ambiental
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