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1.
Artigo em Inglês | MEDLINE | ID: mdl-34637269

RESUMO

Practical applications of carbon anodes in high-power potassium-ion batteries (PIBs) were hampered by their limited rate properties, due to the sluggish K+ transport kinetics in the bulk. Constructing convenient ion/electron transfer channels in the electrode is of great importance to realize fast charge/discharge rates. Here, cross-linked porous carbon nanofibers (inner porous carbon nanotubes and outer soft carbon layer) modified with oxygen-containing functional groups were well designed as anodes to realize robust de-/potassiation kinetics. The novel anode delivered excellent rate capabilities (107 mAh g-1 at 20 A g-1 and 78 mAh g-1 at 40 A g-1) and superior cycling stability (76% capacity retention after 14,000 cycles at 2 A g-1). In situ XRD measurement, in situ Raman spectra, and galvanostatic intermittent titration verified its surface-dominated potassium storage behavior with fast de-/potassiation kinetics, excellent reversibility, and rapid ion/electron transport. Moreover, theoretical investigation revealed that the carboxyl groups in the carbon offered additional capacitive adsorption sites for K+, thus significantly enhancing the reversible capacity. Surprisingly, a full cell using the anode and perylene-3,4,9,10-tetracarboxylic dianhydride cathode achieved an outstanding power density of 23,750 W kg-1 and superior fast charge/slow discharge performance.

2.
Adv Mater ; : e2104761, 2021 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-34632640

RESUMO

Elastomeric dielectrics are crucial for reliably governing the carrier densities in semiconducting channels during deformation in soft/stretchable field-effect transistors (FETs). Uncontrolled stacking of polymeric chains renders elastomeric dielectrics poorly insulated at nanoscale thicknesses, thereby thick films are usually required, leading to high voltage or power consumption for on/off operations of FETs. Here, layer-by-layer assembly is exploited to build 15-nm-thick elastomeric nanodielectrics through alternative adsorption of oppositely charged polyurethanes (PUs) for soft and hysteresis-free FETs. After mild thermal annealing to heal pinholes, such PU multilayers offer high areal capacitances of 237 nF cm-2 and low leakage current densities of 3.2 × 10-8 A cm-2 at 2 V. Owing to the intrinsic ductility of the elastomeric PUs, the nanofilms possess excellent dielectric properties at a strain of 5% or a bending radius of 1.5 mm, while the wrinkled counterparts show mechanical stability with negligible changes of leakage currents after repeated stretching to a strain of 50%. Besides, these nanodielectrics are immune to high humidity and conserve their properties when immersed into water, despite their assembly occurs aqueously. Furthermore, the PU dielectrics are implemented in carbon nanotube FETs, demonstrating low-voltage operations (< 1.5 V) and negligible hysteresis without any encapsulations.

3.
J Nat Prod ; 2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34644092

RESUMO

Characterization of cryptic biosynthetic gene clusters (BGCs) from microbial genomes has been proven to be a powerful approach to the discovery of new natural products. However, such a genome mining approach to the discovery of bioactive plant metabolites has been muted. The plant BGCs characterized to date encode pathways for antibiotics important in plant defense against microbial pathogens, providing a means to discover such phytoalexins by mining plant genomes. Here is reported the discovery and characterization of a minimal BGC from the medicinal plant Catharanthus roseus, consisting of an adjacent pair of genes encoding a terpene synthase (CrTPS18) and cytochrome P450 (CYP71D349). These two enzymes act sequentially, with CrTPS18 acting as a sesquiterpene synthase, producing 5-epi-jinkoheremol (1), which CYP71D349 further hydroxylates to debneyol (2). Infection studies with maize revealed that 1 and 2 exhibit more potent fungicidal activity than validamycin. Accordingly, this study demonstrates that characterization of such cryptic plant BGCs is a promising strategy for the discovery of potential agrochemical leads. Moreover, despite the observed absence of 1 and 2 in C. roseus, the observed transcriptional regulation is consistent with their differential fungicidal activity, suggesting that such conditional coexpression may be sufficient to drive BGC assembly in plants.

4.
Eur Spine J ; 2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34601626

RESUMO

OBJECTIVE: To evaluate the effect of homogeneous spinal-shortening axial decompression procedure (HSAD) on bladder function in patients with spina bifida tethered syndrome. METHODS AND MATERIALS: Patients with tethered spinal cord syndrome were collected prospectively, and all patients were treated with lumbar HSAD. Patients' urodynamic evaluation mainly included detrusor function, sphincter function, sphincter coordination (Ig TLR, ratio of tension and loose of urethral sphincter), and bladder compliance. Meanwhile, all patients were followed up with ICI-Q-SF, SF-12, and Rantala scores. RESULTS: Twenty-four patients were included, with the average age of 27 ± 16 years. At the final follow-up, patients' detrusor function, sphincter function, sphincter coordination, and bladder compliance, were all improved dramatically (all P < 0.01). The preoperative SF-12 score, ICQ, and Rantala score were [52.16 ± 5.64, 14.11 ± 5.25, 7.84 ± 4.87], whereas the postoperative mean was [33.53 ± 3.53, 9.05 ± 4.89, 15 ± 3.77] (P < 0.01, respectively). According to objective evaluation, 16.7% of them recovered to normal. According to the subjective evaluation, 25% of the patients returned to normal. Only one patient (4.2%) deteriorated. Limitations include none-randomized controlled design and limited patient samples. CONCLUSIONS: The HSAD can significantly restore the bladder function in patients with long-term urinary incontinence.

5.
Planta ; 254(5): 98, 2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34657208

RESUMO

MAIN CONCLUSION: Mota Maradi is a sorghum line that exhibits holistic salinity tolerance mechanisms, making it a viable potential donor in breeding efforts for improved sorghum lines. High soil salinity is one of the global challenges for crop growth and productivity. Understanding the salinity tolerance mechanisms in crops is necessary for genetic breeding of salinity-tolerant crops. In this study, physiological and molecular mechanisms in sorghum were identified through a comparative analysis between a Nigerien salinity-tolerant sorghum landrace, Mota Maradi, and the reference sorghum line, BTx623. Significant differences on physiological performances were observed, particularly on growth and biomass gain, photosynthetic rate, and the accumulation of Na+, K+, proline, and sucrose. Transcriptome profiling of the leaves, leaf sheaths, stems, and roots revealed contrasting differentially expressed genes (DEGs) in Mota Maradi and BTx623 which supports the physiological observations from both lines. Among the DEGs, ion transporters such as HKT, NHX, AKT, HAK5, and KUP3 were likely responsible for the differences in Na+ and K+ accumulation. Meanwhile, DEGs involved in photosynthesis, cellular growth, signaling, and ROS scavenging were also identified between these two genotypes. Functional and pathway analysis of the DEGs has revealed that these processes work in concert and are crucial in elevated salinity tolerance in Mota Maradi. Our findings indicate how different complex processes work synergistically for salinity stress tolerance in sorghum. This study also highlights the unique adaptation of landraces toward their respective ecosystems, and their strong potential as genetic resources for future plant breeding endeavors.


Assuntos
Tolerância ao Sal , Sorghum , Ecossistema , Perfilação da Expressão Gênica , Melhoramento Vegetal , Salinidade , Tolerância ao Sal/genética , Sorghum/genética , Estresse Fisiológico , Transcriptoma
6.
BMC Endocr Disord ; 21(1): 204, 2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34663293

RESUMO

BACKGROUND: Atrial natriuretic peptide (ANP) is a cardiovascular and metabolic hormone that has been identified recently as being associated with chronic kidney disease (CKD) without diabetes. Cytokines such as interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and adiponectin (ADP) contribute to the development of type 2 diabetes (T2DM). The aim here was to investigate the relationships of ANP with cytokine levels and clinical variables in T2DM nephropathy patients. METHODS: A total of 81 participants with T2DM were recruited, including 37 patients with normoalbuminuria, 23 patients with microalbuminuria and 21 patients with macroalbuminuria. Serum concentrations of ANP and cytokines were measured using enzyme-linked immunosorbent assay (ELISA) kits. The correlations between ANP and clinical variables were analyzed. Multiple linear regression and logistic regression models were constructed to test the associations between ANP and the severity and presence of albuminuria. RESULTS: The macroalbuminuria patients exhibited higher plasma levels of ANP, TNF-α, IL-6, and ADP; higher serum creatinine (Cr) and blood urea nitrogen (BUN); and longer duration of diabetes mellitus (DM) than the patients with normoalbuminuria and microalbuminuria. Plasma ANP level was significantly associated with TNF-α (r = 0.876, p < 0.001), IL-6 (r = 0.816, p < 0.001) and ADP (r = 0.772, p < 0.001), independent of the duration of DM or the BUN concentration. CONCLUSION: ANP is higher in type 2 diabetes mellitus nephropathy subjects, especially those who have macroalbuminuria, which is associated with compensatory responses to inflammation.

7.
Technol Cancer Res Treat ; 20: 15330338211043975, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34632869

RESUMO

Objective: To investigate the features of helical tomotherapy and co-planar dual Arcs volumetric-modulated arc therapy during prophylactic cranial irradiation associated with bilateral hippocampal tissue sparing. Materials and methods: Helical tomotherapy and co-planar dual arcs volumetric-modulated arc therapy treatment plans were generated with a dose of 30 Gy/10 fractions in 16 patients treated with prophylactic cranial irradiation. The dose to the bilateral hippocampal tissues, organs at risk, and planning target volume were determined when the average dose of bilateral hippocampal tissues was reduced by approximately 4 Gy as an observation point. Changes in dosimetry when sparing the bilateral hippocampal tissues were determined for both modalities. Results: When bilateral hippocampal tissues were restricted to 8 Gy, D40%mean-bilateral hippocampal tissues = 7.64 ± 0.41 Gy in helical tomotherapy, while D40%mean-bilateral hippocampal tissues = 10.96 ± 0.38 Gy in co-planar dual arcs volumetric-modulated arc therapy volumetric-modulated arc therapy. Helical tomotherapy was associated with significantly lower doses to organs at risk, including Dmean-bilateral hippocampal tissues (P = .03), D98%-bilateral hippocampal tissues (P = .01), D2%-bilateral hippocampal tissues (P = .01), Dmean-inner ear (P = .02), Dmean-parotid glands (P = .02), Dmax-lens (P = .02), and Dmax-brainstem (P = .02), but not Dmax-optic nerves (P = .87). Helical tomotherapy provided better target coverage, with lower average D2%-PTV (P = .02), higher average D98%-PTV (P = .02), and better conformal index (0.87 vs 0.84, P = .02) and homogeneity index (0.15 vs 0.21, P = .05). With smaller bilateral hippocampal tissues doses, the planning target volume dose changed across 3 dosimetry regions for both modalities; the plateau region (>20.0 Gy for helical tomotherapy versus >16.0 Gy for co-planar dual arcs volumetric-modulated arc therapy), gradient region (20.0-12.0 Gy vs 16.0-11.0 Gy), and falling region (<12.0 Gy vs <11.0 Gy). The average delivery duration of helical tomotherapy was almost 7.7 times longer than that of co-planar dual arcs volumetric-modulated arc therapy. Conclusions: Helical tomotherapy was better at sparing the bilateral hippocampal tissues and organs at risk and had better target coverage but a significantly longer treatment duration than co-planar dual arcs volumetric-modulated arc therapy. Further dose decreases in the bilateral hippocampal tissues would yield worse target dose coverage.

8.
Med Ultrason ; 2021 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-34508616

RESUMO

AIMS: To investigate the positional relationship between the ovary and Fallopian tube and the relationship between the ovarian position and tubal morphology. MATERIAL AND METHODS: A total of 195 patients with 338 fallopian tubes were enrolled in this retrospective study. The ovarian and tubal positions were defined relative to the uterus in all directions. Tubal morphology was classified as smooth or tortuous. RESULTS: The distribution of the Fallopian tubes corresponded to the positions of the ipsilateral ovaries in the superoinferior direction (χ2 =197.653, p<0.001), mediolateral direction (χ2 =237.447, p <0.001) and anteroposterior direction (χ2 =109.746, p<0.001). Tubal morphology differed according to ovarian position in the superoinferior (χ2 =21.804, p<0.001), mediolateral directions (χ2 =4.679, p=0.031) but not in the anteroposterior direction (χ2 =0.793, p=0.373). CONCLUSIONS: Evaluating the ovarian position can provide preliminary information on the distribution and shapeof the Fallopian tube, helping the operator choose the appropriate initial plane and the necessary approaches for inspection.

9.
Ann Palliat Med ; 10(8): 8701-8708, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34488359

RESUMO

BACKGROUND: There is a lack of data on drug-related problems (DRPs) occurring in nephrology department in China. The objective of this study was to identify and categorize the types and causes of DRPs and to assess their severity. DRPs were examined by clinical pharmacists and the results of their interventions were rated. METHODS: Clinical pharmacists reviewed all medication orders for patients and documented clinical pharmacy services within a nine-month study period. The Pharmaceutical Care Network Europe (PCNE) classification (Version 9.00) was used to identify DRPs. Our Primary outcomes measured the number, causes, types, potential hazards of DRPs and the types and success rate of intervention. RESULTS: Admission medication reconciliation data of 113 patients with chronic kidney disease (CKD) were collected and all of the medications were reviewed retrospectively. Exclude 26 patients who did not occurred DRPs, 87 patients (77%) identified 101 DRPs. The average DRP number per patient was 1.16. The most common type of problem was "treatment effectiveness P1" (84.16%; 85/101). The most common causes were "drug selection C1" (36.00%; 45/125), "dose selection C3" (29.60%; 37/125), and "patient related C7" (26.40%; 33/125). Clinical pharmacists totally proposed 249 interventions, of which 190 (76.31%) were fully accepted and implemented. CONCLUSIONS: DRPs are common among CKD patients in the nephrology department. Hence the necessity for pharmaceutical care to be improved to ensure the ongoing safety of patients.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Nefrologia , Preparações Farmacêuticas , Humanos , Farmacêuticos , Estudos Retrospectivos , Centros de Atenção Terciária
10.
Artigo em Inglês | MEDLINE | ID: mdl-34559308

RESUMO

BACKGROUND: Lenvatinib is regarded as the first-line therapy for patients with unresectable hepatocellular carcinoma (HCC). This study assessed the efficacy and safety of lenvatinib with or without immune checkpoint inhibitors (ICIs) in patients with unresectable HCC. METHODS: In this multicentric retrospective study, patients with unresectable HCC who treated with lenvatinib with or without ICIs would be enrolled. Overall survival, progression-free survival, objective response rate, and disease control rate were calculated to assess the antitumor response. RESULTS: Between January 2019 and August 2020, 65 patients received lenvatinib plus ICIs while other 45 patients received lenvatinib. The baseline characteristics were comparable between the two groups. Lenvatinib plus ICIs provided significantly higher overall survival (hazard ratio = 0.47, 95% CI 0.26-0.85; p = 0.013) and progression-free survival (hazard ratio = 0.35, 95% CI 0.20-0.63; p < 0.001) than lenvatinib monotherapy. Moreover, patients with lenvatinib plus ICIs had significantly higher objective response rate (41.5% vs 20.0%, p = 0.023) and disease control rate (72.3% vs 46.7%, p = 0.009) per RECIST v1.1 than those with lenvatinib. No treatment-related deaths were observed. Grade 3 or greater adverse events occurring in 10% or more of patients in either treatment group were hypertension [13 (20.0%) of 65 patients treated with lenvatinib plus ICIs vs 8 (17.8%) of 45 patients treated with lenvatinib], and palmar-plantar erythrodysesthesia [seven (10.8%) vs two (4.4%)]. CONCLUSIONS: In this real-world study, lenvatinib combined with ICIs showed significantly promising efficacy and manageable safety than lenvatinib alone in patients with unresectable HCC.

11.
Nat Rev Genet ; 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34561623

RESUMO

Plants cannot move, so they must endure abiotic stresses such as drought, salinity and extreme temperatures. These stressors greatly limit the distribution of plants, alter their growth and development, and reduce crop productivity. Recent progress in our understanding of the molecular mechanisms underlying the responses of plants to abiotic stresses emphasizes their multilevel nature; multiple processes are involved, including sensing, signalling, transcription, transcript processing, translation and post-translational protein modifications. This improved knowledge can be used to boost crop productivity and agricultural sustainability through genetic, chemical and microbial approaches.

12.
Small ; : e2103406, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34561967

RESUMO

The controlled assembly of nanowires is one of the key challenges in the development of a range of functional 3D aerogels with unique physicochemical properties for practical applications. However, the deep understanding of the dynamic assemble process for fabricating nanowire aerogels remains elusive. Herein, a facile strategy is presented for the metallic ion-induced assembly of nanowires into macroscopic aerogels via a solution-based process. This method enables the interconnecting between polymer-decorated nanowires via metallic coordination, resulting in plenty of nanowire bundles with the same orientation. Besides, the coordinated binding strength of nanowires with different metallic ions is also discussed. The assembly mechanism that the metallic ions induced dynamic behavior of nanowires is revealed via molecular dynamics theoretical evaluation. These findings benefit for constructing nanowire-based aerogels with unique structural features and multi-function, which pave new opportunities for other material systems.

13.
Chin J Nat Med ; 19(9): 666-674, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34561077

RESUMO

Plant-derived labdane-related diterpenoids (LRDs) represent a large group of terpenoids. LRDs possess either a labdane-type bicyclic core structure or more complex ring systems derived from labdane-type skeletons, such as abietane, pimarane, kaurane, etc. Due to their various pharmaceutical activities and unique properties, many of LRDs have been widely used in pharmaceutical, food and perfume industries. Biosynthesis of various LRDs has been extensively studied, leading to characterization of a large number of new biosynthetic enzymes. The biosynthetic pathways of important LRDs and the relevant enzymes (especially diterpene synthases and cytochrome P450 enzymes) were summarized in this review.

15.
J Inorg Biochem ; 225: 111603, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34564032

RESUMO

Two iridium (III) polypyridine complexes [Ir(ppy)2(BIP)]PF6 (ppy = 2-phenylpyridine, BIP = 2-biphenyl-1H-imidazo[4,5-f][1,10]phenanthroline, Ir1), [Ir(piq)2(BIP)]PF6 (piq = 1-phenylisoquinoline, Ir2) and their liposomes Ir1lipo and Ir2lipo were synthesized and characterized. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to evaluate cytotoxic activity against several cancer cells (A549, HepG2, SGC-7901, Bel-7402, HeLa) and non-cancer cell (mouse embryonic fibroblast, NIH3T3). The results showed that Ir1lipo displays the high cytotoxicity toward SGC-7901 with IC50 value of 5.8 ± 0.2 µM, while the complexes have no cytotoxicity toward A549, HepG2, Bel-7402 and HeLa cells. The cell colony demonstrated that the iridium (III) complexes-loaded liposomes can inhibit cell proliferation, induce cell cycle arrest at G0/G1 phase. Moreover, they also cause autophagy, induce a decrease of mitochondrial membrane potential and increase intracellular reactive oxygen species (ROS) content. These results suggest that the complexes encapsulated liposomes Ir1lipo and Ir2lipo inhibit the growth of SGC-7901 cells through a ROS-mediated mitochondrial dysfunction and activating the PI3K (phosphoinositide-3 kinase)/ AKT (protein kinase B) signaling pathways.

16.
Plant Biotechnol J ; 2021 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-34555248

RESUMO

Bacterial-derived CRISPR/Cas systems are versatile platforms to engineer site-specific gene editing tools. Compared to the canonical Cas9-mediated DNA cleavage systems, which induce a high-proportion of frame-shift mutations, the recently developed base editing (BE) tools allow more precise and predictable base substitutions within a CRISPR/Cas9-defined editing window. Initially, such tools made use of engineered cytosine deaminases or evolved adenine deaminases to catalyze base deamination when fused to a Cas9 nickase (nCas9) (Rees and Liu, 2018).

17.
Endocr J ; 2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34588386

RESUMO

The receptors of chemokines play a significance role in the aggressiveness of tumor. CXCR4/CXCR7 promote metastasis of papillary thyroid carcinoma (PTC). This study examined the expresssion of chemokine receptors CXCR4/CXCR7 in human tissue specimens of PTC and peritumoral nonmalignant tissues. The correlation between CXCR4/CXCR7 and the clinicopathological factors in PTC was also determined. CXCR4/CXCR7 were examined in 115 PTC tissues from 115 patients using immunohistochemistry. Staining intensity was compared with patients and tumor characteristics including gender, age, tumor size, capsule invasion, multifocality, lymph node metastasis, and nature of paracancerous tissue. [Statistics: rank sum test, Spearman rank order correlation test; p < 0.05]. Higher expression rates of CXCR4/CXCR7 exhibited in PTC compared with peritumoral nonmalignant tissues. The expression of them was correlated in cancer and paracancerous specimens. A trend toward higher CXCR4/CXCR7 expression was found among tumors showing positive lymph nodes and capsule invasion, while no association with sex, age, tumor size, and nature of paracancerous tissue. Number of lymph nodes was associated with higher intensity IHC staining for CXCR4/CXCR7. Intense staining for CXCR4 was also associated with multifocality. Expression of CXCR4/CXCR7 by PTCs was correlated with lymph node metastasis and capsule invasion. Although multiple bias, they were thought to play a significance role in the aggressiveness of PTC, which provides potential targets for therapeutic interventions.

18.
Andrology ; 2021 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-34536053

RESUMO

BACKGROUND: Currently, there is no consensus on the effect of obstructive sleep apnea on male serum testosterone levels. This systematic review and meta-analysis aimed to determine the association between obstructive sleep apnea and male serum testosterone level. METHODS: The literature related to obstructive sleep apnea and male serum testosterone in the PubMed, Embase, and Cochrane Library databases were searched from their inception to June 10, 2021. Data were pooled using the Stata 15 software. We performed a subgroup analysis of studies after matching the age and body mass index, as well as according to the severity of obstructive sleep apnea. RESULTS: Eighteen studies involving 1823 men were included in the systematic review and meta-analysis. A significant inverse association between obstructive sleep apnea and male serum testosterone (SMD = -0.76; 95% CI: -1.18, -0.33; p = 0.001) was found. After adjusting for age and body mass index, this inverse association still existed (SMD = -0.8; 95% CI = -1.41, -0.18, p = 0.012). According to the subgroup analysis of obstructive sleep apnea severity, our results showed that serum testosterone was not significantly decreased in mild (SMD = -0.58; 95% CI = -1.88, 0.73, p = 0.386) and moderate obstructive sleep apnea patients (SMD = -0.94; 95% CI = -2.04, 0.15, p = 0.092), whereas it was significantly reduced in patients with severe obstructive sleep apnea (SMD = -1.21; 95% CI = -2.02, -0.41, p = 0.003). CONCLUSIONS: Obstructive sleep apnea is inversely associated with male serum testosterone levels, independent of body mass index and age. Notably, the severity of obstructive sleep apnea is also correlated with male serum testosterone, which is significantly reduced in patients with severe obstructive sleep apnea.

19.
Ecotoxicol Environ Saf ; 225: 112745, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34481349

RESUMO

In the present work, hematite-boron-carbonitride (Fe2O3-BCN) nanosheets were synthesized by a simple hydrothermal reaction and the following high temperature treatment. The morphology, structure and chemical composition of the as-prepared material were carefully characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The Fe2O3-BCN nanosheets were used to modified on the surface of the glassy carbon electrode to fabricate an electrochemical sensor for lead ions (Pb(II)) via differential pulse anodic stripping voltammetry (DPASV). At the same time, the influence of the modification concentration, solution acidity, deposition potential and deposition time on response peak current of Pb(II) at the Fe2O3-BCN-based electrochemical sensor was well investigated. Under the optimized conditions, the electrochemical signal and concentration of Pb(II) show two-stage linear relationship in the range of 0.5 - 40 µg/L and 40 -140 µg/L, with a limit of detection (LOD) of 0.129 µg/L. The Fe2O3-BCN-based electrochemical sensor shows excellent selectivity and anti-interference ability in the anti-interference experiments and actual sample analysis experiments, revealing its broad application in environmental monitoring of Pb(II).


Assuntos
Nanopartículas , Água , Compostos Férricos , Íons , Chumbo
20.
J Orthop Surg Res ; 16(1): 544, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34470653

RESUMO

OBJECTIVE: We aimed to evaluate risk factors and develop a nomogram for reoperation after internal fixation of nondisplaced femoral neck fractures (FNFs) in elderly patients. METHODS: We conducted a retrospective study involving a total of 255 elderly patients who underwent closed reduction and internal fixation with cannulated screw system for nondisplaced FNFs between January 2016 and January 2019. We collected data on demographics, preoperative radiological parameters, surgery, serum biochemical markers, and postoperative rehabilitation. In addition, we performed univariate and multivariate logistic regression analyses to determine independent risk factors for reoperation, and then developed a nomogram to assess the risks of reoperation. Besides, discriminative ability, calibration, and clinical usefulness of the nomogram were evaluated using the concordance index (C-index), the receiver operating characteristic (ROC) curve, calibration curve and decision curve analysis (DCA), respectively. We employed bootstrap method to validate the performance of the developed nomogram. RESULTS: Our analysis showed that among the 255 patients, 28 (11.0%) underwent reoperation due to osteonecrosis of the femoral head (14 cases), mechanical failure (8 cases) or nonunion (6 cases). All of the 28 patients underwent conversion surgery to arthroplasty. The multivariate logistic regression analysis demonstrated that preoperative posterior tilt angle ≥ 20°, Pauwel's III type, younger patients, preoperative elevated levels of alkaline phosphatase (ALP), preoperative hypoalbuminemia, and early postoperative weight-bearing were independent risk factors for reoperation. In addition, the C-index and the bootstrap value of the developed nomogram was 0.850 (95% CI = 0.803-0.913) and 0.811, respectively. Besides, the calibration curve showed good consistency between the actual diagnosed reoperation and the predicted probability, while the DCA indicated that the nomogram was clinically valuable. CONCLUSIONS: Our analysis showed we successfully developed and validated a nomogram for personalized prediction of reoperation after internal fixation of nondisplaced FNFs in elderly patients. This model would help in individualized evaluation of the need for reoperation and inform strategies aimed at eliminating the need for the reoperation.

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