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1.
Artigo em Inglês | MEDLINE | ID: mdl-33949212

RESUMO

The outcomes of coronavirus disease 2019 (COVID-19) vary between men and women. Some statistical reports have shown that men have a higher risk of developing COVID-19 and suffer from worse outcomes than females. While there are many factors that can explain the high prevalence of COVID-19 in men, such as lifestyle habits and the different profile of comorbidities among sexes, the distinctions between male and female immune systems cannot be ignored. It has been sufficiently shown that sex differences have a critical influence on the shaping of immune response, which then leads to different pathogenesis in infectious diseases. Compared with males, females typically have a more effective innate and adaptive immune response to viral infections in COVID-19. What's more, there is a growing body of evidence showing that estrogen exerts an effect on the regulation of immune response. This article examines the effect and mechanism of estrogen on COVID-19.

2.
Int Psychogeriatr ; : 1-10, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33966685

RESUMO

OBJECTIVE: To examine the association between sleep duration in different stages of life and amnestic mild cognitive impairment (aMCI). DESIGN, SETTING, AND PARTICIPANTS: A total of 2472 healthy elderly and 505 patients with aMCI in China were included in this study. The study analyzed the association between aMCI and sleep duration in different stages of life. MEASUREMENTS: We compared sleep duration in different stages of life and analyzed the association between Montreal Cognitive Assessment scores and sleep duration by curve estimation. Logistic regression was used to evaluate the association between aMCI and sleep duration. RESULTS: In the analysis, there were no results proving that sleep duration in youth (P = 0.719, sleep duration < 10 hours; P = 0.999, sleep duration ≥ 10 hours) or midlife (P = 0.898, sleep duration < 9 hours; P = 0.504, sleep duration ≥ 9 hours) had a significant association with aMCI. In the group sleeping less than 7 hours in late life, each hour more of sleep duration was associated with approximately 0.80 of the original risk of aMCI (P = 0.011, odds ratio = 0.80, 95% confidence interval = 0.68-0.95). CONCLUSIONS: Among the elderly sleeping less than 7 hours, there is a decreased risk of aMCI for every additional hour of sleep.

3.
J Clin Lab Anal ; : e23780, 2021 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-33942366

RESUMO

BACKGROUND: Recent studies have revealed that super-enhancer-associated long noncoding RNAs (SE-LncRNAs) act pivotal roles in carcinogenesis. This study aimed to report the identification of a novel SE-LncRNA, RP11-569A11.1, and its functional role in colorectal cancer (CRC) progression. METHODS: Arraystar human SE-LncRNA microarray was performed to detect differentially expressed SE-LncRNAs in CRC tissues. RT-qPCR was conducted to detect the expression level of RP11-569A11.1 in CRC tissues and cells. The ROC curve was used to analyze the sensitivity and specificity of RP11-569A11.1 in CRC diagnosis. CCK-8 assay, colony formation assay, flow cytometry assay, and transwell assay were used to study the function of RP11-569A11.1. RNA-seq array was performed to analyze the potential downstream target gene of RP11-569A11.1. Western blot assay was conducted to measure the protein level of interferon-induced protein with tetratricopeptide repeat 2 (IFIT2). RESULTS: A total of 23 (15 up- and 8 downregulated) significantly expressed SE-LncRNAs were identified in CRC tissues. The top 8 upregulated SE-LncRNAs were RP11-893F2.9, PTCSC1, RP11-803D5.4, AC005592.2, LINC00152, LINC01232, AC017002.1, and RP4-673M15.1, and the top 8 downregulated SE-LncRNAs were RP11-569A11.1, RP11-245G13.2, RP11-556N21.1, U91328.19, AX748340, CTD-2337J16.1, CATG00000108830.1, and RP11-670E13.2. Of which, RP11-569A11.1 was found to be significantly downregulated in CRC tissues and cells. ROC curve analysis showed the area under the curve (AUC) of 0.77 [95% confidence interval (CI), 0.660-0.884, p < 0.001], and the diagnostic sensitivity and specificity were 74.29% and 71.43%, respectively. Functionally, overexpression of RP11-569A11.1 inhibited CRC cell proliferation, migration and invasion, and induced cell apoptosis, while knockdown of RP11-569A11.1 generated an opposite effect. Mechanistically, RP11-569A11.1 positively regulated IFIT2 expression in CRC cells. CONCLUSION: RP11-569A11.1 inhibited CRC tumorigenesis by IFIT2-dependent and could serve as a promising diagnostic biomarker in CRC.

4.
Int J Legal Med ; 2021 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-33950286

RESUMO

The MinION nanopore sequencing device (Oxford Nanopore Technologies, Oxford, UK) is the smallest commercially available sequencer and can be used outside of conventional laboratories. The use of the MinION for forensic applications, however, is hindered by the high error rate of nanopore sequencing. One approach to solving this problem is to identify forensic genetic markers that can consistently be typed correctly based on nanopore sequencing. In this pilot study, we explored the use of nanopore sequencing for single nucleotide polymorphism (SNP) and short tandem repeat (STR) profiling using Verogen's (San Diego, CA, USA) ForenSeq DNA Signature Prep Kit. Thirty single-contributor samples and DNA standard material 2800 M were genotyped using the Illumina (San Diego, CA, USA) MiSeq FGx and MinION (with R9.4.1 flow cells) devices. With an optimized cutoff for allelic imbalance, all 94 identity-informative SNP loci could be genotyped reliably using the MinION device, with an overall accuracy of 99.958% (1 error among 2926 genotypes). STR typing was notably error prone, and its accuracy was locus dependent. We developed a custom-made bioinformatics workflow, and finally selected 13 autosomal STRs, 14 Y-STRs, and 4 X-STRs showing high consistency between nanopore and Illumina sequencing among the tested samples. These SNP and STR loci could be candidates for panel design for forensic analysis based on nanopore sequencing.

5.
Phys Rev Lett ; 126(15): 156401, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33929224

RESUMO

Higher-order topological insulators (HOTIs), a new horizon of topological phases of matter, host lower-dimensional corner or hinge states, providing important stepping stones to the realization of robust topological waveguides in higher dimensions. The nontrivial band topology that gives rise to the corner or hinge states is usually enabled by certain crystalline symmetries. As a result, higher-order topological boundary states are tied to specific corners or hinges, lacking the flexibility of switching and selecting. Here, we report the experimental realization of topologically switchable and valley-selective corner states in a two-dimensional sonic crystal. Such intriguing properties are enabled by exploiting the higher-order topology assisted with the valley degree of freedom. For this purpose, we realize a valley HOTI of second-order topology characterized by the nontrivial bulk polarization. Interestingly, the hosted corner states are found to be valley dependent and therefore enable flexible control and manipulation on the wave localization. Topological switch on or off and valley selection of the corner states are directly observed through spatial scanning of the sound field. We further design an arbitrary structure of complex patterns containing corners with various intersection angles, among which selected corners can be illuminated or darkened upon valley selection. The reported valley HOTI and the valley-selective corner states provide fundamental understanding on the interplay between higher-order topology and valley degree of freedom and pave the way for lower-dimensional valleytronics, which may find potential applications in integrated acoustics and photonics.

6.
Nanoscale ; 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33929480

RESUMO

Atherosclerotic thrombosis is the leading cause of most life-threatening cardiovascular diseases (CVDs), particularly as a result of rupture or erosion of vulnerable plaques. Rupture or erosion-prone plaques are quite different in cellular composition and immunopathology, requiring different treatment strategies. The current imaging technology cannot distinguish the types of vulnerable plaques, and thus empirical treatment is still applied to all without a tailored and precise treatment. Herein, we propose a novel strategy called "Multifunctional Pathology-mapping Theranostic Nanoplatform (MPmTN)" for the tailored treatment of plaques based on the pathological classification. MPmTNs are made up of poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs), containing contrast imaging materials Fe3O4 and perfluoropentane (PFP), and coated with specific plaque-targeted peptides PP1 and cyclic RGD. The PFP encapsulated inside the MPmTN can undergo a phase change from nanodroplets to gas microbubbles under therapeutic ultrasound (TUS) exposure. The acoustic and biological effects induced by TUS and disruption of microbubbles may further promote therapeutic effects. Hypothetically, MPmTN NPs can target the rupture-prone plaque via the binding of PP1 to class A scavenger receptors (SR-A) on macrophages, induce the apoptosis due to TUS exposure and thus reduce the chronic soakage of inflammatory cells. The MPmTN NPs can also target the erosion-prone plaque through the binding of cRGD to glycoprotein (GP) IIb/IIIa on activated platelets and promote platelet disaggregation under TUS exposure. Therefore, MPmTNs may work as a multifunctional pathology-mapping therapeutic agent. Our in vitro results show that the MPmTN with PP1 and cRGD peptides had a high binding affinity both for activated macrophages and blood clots. Under TUS exposure, the MPmTN could effectively induce macrophage apoptosis, destroy thrombus and exhibit good imaging properties for ultrasound (US) and MRI. In apoE-/- mice, MPmTNs can selectively accumulate at the plaque site and reduce the T2-weighted signal. The apoptosis of macrophages and disaggregation of activated platelets on the plaques were also confirmed in vivo. In summary, this study provides a potential strategy for a tailored treatment of vulnerable plaques based on their pathological nature and a multimodal imaging tool for the risk stratification and assessment of therapeutic efficacy.

7.
Front Immunol ; 12: 609700, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33868230

RESUMO

Objectives: Gut dysbiosis is associated with chronic kidney disease (CKD), and serum free immunoglobulin light chains (FLCs) are biomarkers for CKD. This study aims to assess the CKD gut microbiome and to determine its impact on serum FLC levels. Methods: To control for confounders, 100 patients and sex- and age-matched healthy controls (HCs) were recruited. The gut microbiome was assessed by sequencing 16S rRNA gene V3-V4 hypervariable regions. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States was applied to infer functional metabolic pathways. When observing group differences in the microbiome and predicted metabolic pathways, demographic confounders were adjusted using binary logistic regression; when examining impacts of the gut microbiome and metabolic pathways on serum FLCs, factors influencing FLC levels were adjusted using multiple regression. Results: Principal coordinate analysis revealed a significantly different bacterial community between the CKD and HC groups (P < 0.05). After adjusting for confounders, lower Chao 1, observed species and Shannon indices based on binary logistic regression predicted CKD prevalence. Actinobacteria, Alistipes, Bifidobacterium and Bifidobacterium longum enrichment, upregulation of metabolic pathways of bacterial toxin, chloroalkane and chloroalkene degradation, and Staphylococcus aureus infection also predicted CKD prevalence (P < 0.05). Furthermore, depletion of Actinobacteria and Bifidobacterium and reduced chloroalkane and chloroalkene degradation predicted high levels of FLC λ (P < 0.05). Conclusions: Gut dysbiosis in CKD patients was confirmed by controlling for confounders in the present study. Additionally, the association between gut dysbiosis and FLC λ levels demonstrates the existence of crosstalk between the microbiome and immune response in CKD.

8.
Neuron ; 109(7): 1070-1071, 2021 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-33831360

RESUMO

Striatal dopamine and acetylcholine are thought to be imbalanced in Parkinson's disease. In this issue of Neuron, Cai et al. report that restoration of nigral glutamate co-transmission, acting on dorsolateral striatal cholinergic interneuron mGluR1s, can rescue motor dysfunction in a mouse model of Parkinson's.


Assuntos
Transtornos Motores , Doença de Parkinson , Acetilcolina , Animais , Colinérgicos , Corpo Estriado , Crime , Dopamina , Ácido Glutâmico , Interneurônios , Camundongos
9.
J Neurol ; 2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33885974

RESUMO

BACKGROUND: To assess whether stroke patients admitted to stroke units (SU) have a better short-term outcome than those treated in conventional wards (CW). METHODS: A total of 20 hospitals from 16 provinces in China were initially selected in this study. Finally, 24,090 consecutive admissions in 2013-2015 treated in CW and 21,332 consecutive entries in 2017-2019 treated in SU were included. The primary endpoint of this study was the all-cause death or dependency condition three months after admission. RESULTS: Patients in the SU group were more likely receiving thrombolytic therapy (3.9 vs 2.1%) and intravascular treatment (1.2 and 0.7%). In-hospital death were lower in the SU group than the CW group (SU vs CW: 2.93 vs 4.58% [absolute difference, - 2.28% {95% CI, - 3.32% to - 0.93%}, odd ratio {OR}, 0.72{95% CI, 0.61 to 0.82}]. Death after discharge was also lower in the SU group than the CW (SU vs CW: 5.07 vs 6.72% [absolute difference, - 2.33% {95% CI, - 3.39% to - 0.90%}, odd ratio {OR}, 0.75{95% CI, 0.68 to 0.84}]. In addition, patients who received SU care were less likely to be dead or disabled than those patients who received CW care after adjusting for other variability (SU vs CW: 36.20 vs 44.33% [absolute difference, - 11.33% {95% CI, - 15.32% to - 7.14%}, odd ratio {OR}, 0.78{95% CI, 0.80 to 0.85}]. CONCLUSIONS: Among patients with stroke, admission to a designated SU was associated with modestly lower mortality at discharge, reduced probability of death, or being disabled at the end of follow-up.

10.
J Plant Physiol ; 261: 153419, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33915366

RESUMO

Zinc (Zn) is an essential micronutrient for plants and animals. Because of its low availability in arable soils worldwide, Zn deficiency is becoming a serious agricultural problem resulting in decreases of crop yield and nutritional quality. Plants have evolved multiple responses to adapt to low levels of soil Zn supply, involving biochemical and physiological changes to improve Zn acquisition and utilization, and defend against Zn deficiency stress. In this review, we summarize the physiological and biochemical adaptations of plants to Zn deficiency, the roles of transporters and metal-binding compounds in Zn homeostasis regulation, and the recent progresses in understanding the sophisticated regulatory mechanisms of Zn deficiency responses that have been made by molecular and genetic analyses, as well as diverse 'omics' studies. Zn deficiency responses are tightly controlled by multiple layers of regulation, such as transcriptional regulation that is mediated by transcription factors like F-group bZIP proteins, epigenetic regulation at the level of chromatin, and post-transcriptional regulation mediated by small RNAs and alternative splicing. The insights into the regulatory network underlying Zn deficiency responses and the perspective for further understandings of molecular regulation of Zn deficiency responses have been discussed. The understandings of the regulatory mechanisms will be important for improving Zn deficiency tolerance, Zn use efficiency, and Zn biofortification in plants.

11.
Medicine (Baltimore) ; 100(16): e25517, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33879689

RESUMO

RATIONALE: Primary schwannoma of the thyroid gland is very rare, and its preoperative diagnosis is difficult. PATIENT CONCERNS: We report the case of a thyroid nodule in an 18-year-old woman, who presented with a mass in her left neck with stiffness and normal thyroid function. However, the patient complained of numbness in her left upper extremity, and ultrasound (US) features were suspicious of malignancy. DIAGNOSES: Multimodal US imaging was performed using B-mode, color doppler, ultrasonic elastography (UE), and contrast-enhanced ultrasound (CEUS). CEUS revealed heterogeneous enhancement and "target sign" within the tumor. The nodule was suspicious for malignancy and classified as TI-RADS 4b, while the elasticity values measured by UE indicated a benign lesion. Fine needle aspiration (FNA) was subsequently performed in the markedly contrast-enhanced area for biopsy. Cytological results revealed a benign schwannoma. INTERVENTION: The patient underwent left lobe resection. Postoperative pathology confirmed it to be a primary benign schwannoma of the thyroid. OUTCOMES: After thyroidectomy, the patient was followed-up with US. At present, all laboratory tests and thyroid imaging are normal, and the numbness of the left upper limb has disappeared. LESSONS: The combination of different US modalities is useful for the diagnosis of thyroid lesions. FNA performed under CEUS guidance improves the accuracy of biopsy sampling.


Assuntos
Técnicas de Imagem por Elasticidade/métodos , Neurilemoma/diagnóstico , Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/diagnóstico , Ultrassonografia Doppler em Cores/métodos , Adolescente , Biópsia por Agulha Fina , Meios de Contraste/administração & dosagem , Feminino , Humanos , Imagem Multimodal/métodos , Neurilemoma/patologia , Neurilemoma/cirurgia , Glândula Tireoide/patologia , Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Resultado do Tratamento
12.
Mol Ecol Resour ; 2021 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-33817972

RESUMO

Manchurian walnut (Juglans mandshurica Maxim.) is a synonym of J. cathayensis, a diploid, vulnerable, temperate deciduous tree valued for its wood and nut. It is also valued as a rootstock for Juglans regia because of its reported tolerance of lesion nematode. Reference genomes are available for several Juglans species, our goal was to produce a de novo, chromosome-level assembly of the J. mandshurica genome. Here, we reported an improved assembly of J. mandshurica with a contig N50 size of 6.49 Mb and a scaffold N50 size of 36.1 Mb. The total genome size was 548 Mb encoding 29,032 protein coding genes which were annotated. The collinearity analysis showed that J. mandshurica and J. regia originated from a common ancestor, with both species undergoing two WGD events. A genomic comparison showed that J. mandshurica was missing 1657 genes found in J. regia, and J. mandshurica includes 2827 genes not found in of the J. regia genome. The J. mandshurica contained 1440 unique paralogues that were highly enriched for flavonoid biosynthesis, phenylpropanoid biosynthesis, and plant-pathogen interaction. Four gene families related to disease resistance notable contraction (rapidly evolving; LEA, WAK, PPR, and PR) in J. mandshurica compared to eight species. JmaPR10 and JmaPR8 contained three orthologous gene pairs with J. regia that were highly expressed in root bark. JmaPR10 is a strong candidate gene for lesion nematodes resistance in J. mandshurica. The J. mandshurica genome should be a useful resource for study of the evolution, breeding, and genetic variation in walnuts (Juglans).

13.
Transl Stroke Res ; 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33852132

RESUMO

Neuroinflammation is closely associated with poor prognosis in patients with subarachnoid hemorrhage (SAH). The purpose of this study was to investigate the role of neutrophil extracellular traps (NETs), which are important regulators of sterile inflammation, in SAH. In this study, markers of NET formation, quantified by the level of citrullinated histone H3 (CitH3), were significantly increased after SAH and correlated with SAH severity. CitH3 peaked at 12 h in peripheral blood and at 24 h in the brain. Administration of the peptidyl arginine deiminase 4 (PAD4) selective antagonist GSK484 substantially attenuated SAH-induced brain edema and neuronal injury. Moreover, the benefit of NET inhibition was also confirmed by DNAse I treatment and neutrophil depletion. Mechanistically, NETs markedly exacerbated microglial inflammation in vitro. NET formation aggravated neuroinflammation by promoting microglial activation and increased the levels of TNF-α, IL-1ß, and IL-6, while inhibiting NETs demonstrated anti-inflammatory effects by decreasing the levels of these proinflammatory factors. Moreover, neurogenic pulmonary edema (NPE), a severe nonneurological complication after SAH, is associated with a high level of NET formation. However, GSK484 effectively inhibited the formation of NETs in the lungs of NPE mice, thereby preventing the diffusion of neutrophilic infiltration and attenuating the swelling of the alveolar interstitium. In conclusion, NETs promoted neuroinflammation after SAH, while pharmacological inhibition of PAD4-NETs could reduce the inflammatory damage caused by SAH. These results supported the idea that NETs might be potential therapeutic targets for SAH.

14.
Virol Sin ; 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33835391

RESUMO

The ongoing coronavirus disease 2019 (COVID-19) pandemic caused more than 96 million infections and over 2 million deaths worldwide so far. However, there is no approved vaccine available for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the disease causative agent. Vaccine is the most effective approach to eradicate a pathogen. The tests of safety and efficacy in animals are pivotal for developing a vaccine and before the vaccine is applied to human populations. Here we evaluated the safety, immunogenicity, and efficacy of an inactivated vaccine based on the whole viral particles in human ACE2 transgenic mouse and in non-human primates. Our data showed that the inactivated vaccine successfully induced SARS-CoV-2-specific neutralizing antibodies in mice and non-human primates, and subsequently provided partial (in low dose) or full (in high dose) protection of challenge in the tested animals. In addition, passive serum transferred from vaccine-immunized mice could also provide full protection from SARS-CoV-2 infection in mice. These results warranted positive outcomes in future clinical trials in humans.

15.
Nutr Metab Cardiovasc Dis ; 31(5): 1391-1400, 2021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-33812733

RESUMO

BACKGROUND AND AIMS: Obesity has been linked to the development of hypertension, but the comparison of relationships between different obesity parameters with hypertension are scarcely studied with nationally representative Chinese adults samples. We sought to compare the predictive strengths of different obesity indicators to hypertension. METHODS AND RESULTS: Data in this study were obtained from the Chinese National Stroke Prevention Project with a nationally representative sample of Chinese aged 40 years and older. A total of 162,880 individuals were included. Multi-level analyses and Receiver Operating Characteristic (ROC) curves were used to examine the risk of hypertension in relation to different obesity parameters, including body mass index (BMI), waist circumference (WC), lipid accumulation product index (LAP), visceral adiposity index (VAI), and body adiposity index (BAI). As results, the BMI, WC, LAP, VAI, and BAI were positively associated with the risk of hypertension (P < 0.001). In total, BMI had the strongest association with hypertension when compared with other obesity indicators, and one SD up of BMI would increase the risk of hypertension by 53.9% (95% CI: 1.514-1.566). For men, WC was most associated with hypertension, and one SD up of WC would increase the risk of hypertension by 73.3% (95% CI: 1.685-1.782). For women, BMI showed the strongest predictive power, one SD up of BMI would increase the risk of hypertension by 51.0% (95% CI: 1.479-1.543). CONCLUSIONS: BMI, WC, LAP, VAI, and BAI are all positively corrected to hypertension, but gender disparities should be considered in predicting hypertension by obesity indicators.

16.
Ying Yong Sheng Tai Xue Bao ; 32(3): 1054-1060, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33754572

RESUMO

Both biodiversity conservation and the construction of biological habitat networks are key components of territorial spatial planning in China. Improving the landscape functional connectivity of biological habitat networks plays a vital role in biodiversity conservation. Although biological habitat network planning is a hot topic in literature, there is still lack of operable technological and methodological support in practical planning. According to the graph theory, the following three different aspects of biodiversity conservation and ecological network construction should be addressed in territorial spatial planning. First, the importance of biological habitat patches should be evaluated to determine the priority of patch protection. Second, the best locations for adding new elements should be identified to increase landscape functional connectivity of biological habitat network. Third, the impacts of construction projects should be judged and the potential impact of new construction projects according to the reduction of landscape function connectivity should be evaluated. We applied such framework to the network planning of amphibian (Pelophylax nigromaculata) habitat in Xiong'an New Area. The results showed that graph theory approach effectively met the requirements of those three aspects. The identification of the five optimal locations of new habitats of P. nigromaculata improved the overall landscape functional connectivity of habitat network by 19%. Four optimal locations of cross passage were identified to reduce the impacts of G45 expressway by assessing its impacts on functional connectivity of the amphibian habitat network.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Biodiversidade , China , Ranidae
17.
Orthop Surg ; 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33749146

RESUMO

OBJECTIVE: To describe a surgical technique using suture tape for reconstruction of the medial patellofemoral ligament (MPFL). This technique restores the stability of the reconstructed ligament and has excellent postoperative outcomes. METHOD: This is a retrospective analysis. From January 2016 to June 2018, 17 patients underwent MPFL reconstruction using high-strength suture (FiberTape; Arthrex) augmentation, with at least 12 months of follow up. There were 11 female and 6 male patients. The mean age at the time of MPFL reconstruction was 22.1 years (range 13-34 years). Clinical outcomes included pain level, knee range of motion, passive patellar hypermobility, and maltracking at follow-up. The lateral patellofemoral angles, congruence angles, and patellar tilt angles were measured in a skyline view by CT at 30° of knee flexion at 12 months. Functional outcomes were assessed using the Lysholm knee scoring scale, the SF-12 score, the Tegner score, and the Crosby and Insall grading system at yearly follow-up. RESULT: No patients were lost at the last follow up. One patient had recurrence of patellar dislocation and none of the others had serious complications. The success rate of MPFL repair for preventing recurrent dislocations was 94.1% (16 of 17 knees). Fifteen knees had full range of motion of more than 130°. At follow-up, 2 knees were judged to have mild hypermobility and none had severe hypermobility or maltracking. Using the Crosby and Insall grading system, 12 knees (70.6%) were graded as excellent, 4 knees (23.5%) as good, 1 knee (5.9%) as fair to poor, and none as worse at the last follow-up assessment. In all patients, the Lysholm knee score (55.12 ± 13.52 vs 79.88 ± 7.50, P < 0.01), the SF-12 score (47 ± 9.53 vs 65.24 ± 12.82, P < 0.01), and the Tegner score (2.76 ± 1.39 vs 6.53 ± 1.70, P < 0.01) had improved at their 12-month follow up. Compared with preoperative radiological findings, there was a significant improvement in lateral patellofemoral angle (-10.24 ± 7.10 vs 6 ± 5.43, P < 0.01), patellar tilt angle (26.53 ± 7.23 vs 9.88 ± 4.24, P < 0.01), and congruence angle (29.59 ± 11.95 vs -8.65 ± 4.86, P < 0.01). CONCLUSION: The use of FiberTape in MPFL reconstruction can improve the stability of the knee following surgery and has good midterm clinical results and low complication rates.

18.
Environ Sci Technol ; 55(8): 5236-5247, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33779159

RESUMO

Solid amine adsorbents are among the most promising CO2 adsorption technologies for biogas upgrading due to their high selectivity toward CO2, low energy consumption, and easy regeneration. However, in most cases, these adsorbents undergo severe chemical inactivation due to urea formation when regenerated under a realistic CO2 atmosphere. Herein, we demonstrated a facile and efficient synthesis route, involving the synthesis of nano-Al2O3 support derived from coal fly ash with a CO2 flow as the precipitant and the preparation of polyethylenimine (PEI)-impregnated Al2O3-supported adsorbent. The optimal 55%PEI@2%Al2O3 adsorbent showed a high CO2 uptake of 139 mg·g-1 owing to the superior pore structure of synthesized nano-Al2O3 support and exhibited stable cyclic stability with a mere 0.29% decay per cycle even under the realistic regenerated CO2 atmosphere. The stabilizing mechanism of PEI@nano-Al2O3 adsorbent was systematically demonstrated, namely, the cross-linking reaction between the amidogen of a PEI molecule and nano-Al2O3 support, owing to the abundant Lewis acid sites of nano-Al2O3. This cross-linking process promoted the conversion of primary amines into secondary amines in the PEI molecule and thus significantly enhanced the cyclic stability of PEI@nano-Al2O3 adsorbents by markedly inhibiting the formation of urea compounds. Therefore, this facile and efficient strategy for PEI@nano-Al2O3 adsorbents with anti-urea properties, which can avoid active amine content dilution from PEI chemical modification, is promising for practical biogas upgrading and various CO2 separation processes.


Assuntos
Biocombustíveis , Polietilenoimina , Adsorção , Dióxido de Carbono , Ureia
19.
Molecules ; 26(4)2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33670156

RESUMO

Recently, metal-coordinated orthogonal self-assembly has been used as a feasible and efficient method in the construction of polymeric materials, which can also provide supramolecular self-assembly complexes with different topologies. Herein, a cryptand with a rigid pyridyl group on the third arm derived from BMP32C10 was synthesized. Through coordination-driven self-assembly with a bidentate organoplatinum(II) acceptor or tetradentate Pd(BF4)2•4CH3CN, a di-cryptand complex and tetra-cryptand complex were prepared, respectively. Subsequently, through the addition of a di-paraquat guest, linear and cross-linked supramolecular polymers were constructed through orthogonal self-assembly, respectively. By comparing their proton nuclear magnetic resonance (1H NMR) and diffusion-ordered spectroscopy (DOSY) spectra, it was found that the degrees of polymerization were dependent not only on the concentrations of the monomers but also on the topologies of the supramolecular polymers.


Assuntos
Complexos de Coordenação/química , Éteres Cíclicos/química , Metais/química , Paraquat/química , Bases de Schiff/química , Substâncias Macromoleculares/química , Estrutura Molecular , Polímeros/química
20.
Nat Commun ; 12(1): 1636, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33712623

RESUMO

We in-situ observe the ultrafast dynamics of trapped carriers in organic methyl ammonium lead halide perovskite thin films by ultrafast photocurrent spectroscopy with a sub-25 picosecond time resolution. Upon ultrafast laser excitation, trapped carriers follow a phonon assisted tunneling mechanism and a hopping transport mechanism along ultra-shallow to shallow trap states ranging from 1.72-11.51 millielectronvolts and is demonstrated by time-dependent and independent activation energies. Using temperature as an energetic ruler, we map trap states with ultra-high energy resolution down to < 0.01 millielectronvolt. In addition to carrier mobility of ~4 cm2V-1s-1 and lifetime of ~1 nanosecond, we validate the above transport mechanisms by highlighting trap state dynamics, including trapping rates, de-trapping rates and trap properties, such as trap density, trap levels, and capture-cross sections. In this work we establish a foundation for trap dynamics in high defect-tolerant perovskites with ultra-fast temporal and ultra-high energetic resolution.

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