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1.
Langmuir ; 40(3): 1892-1901, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38192235

RESUMO

Polyelectrolyte complexes (PECs) have emerged as an attractive category of materials for their water processability and some similarities to natural biopolymers. Herein, we employ the intrinsic hydroplasticity of PEC materials to enable the generation of porous structures with the aid of gas foaming. Such foamable materials are fabricated by simply mixing polycation, polyanion, and a UV-initiated chemical foaming agent in an aqueous solution, followed by molding into thin films. The gas foaming of the PEC films can be achieved upon exposure to UV illumination under water, where the films are plasticized and the gaseous products from the photolysis of foaming agents afford the formation, expanding, and merging of numerous bubbles. The porosity and morphology of the resulting porous films can be customized by tuning film composition, foaming conditions, and especially the degree of plasticizing effect, illustrating the high flexibility of this hydroplastic foaming method. Due to the rapid initiation of gas foaming, the present method enables the formation of porous structures via an instant one-step process, much more efficient than those existing strategies for porous PEC materials. More importantly, such a pore-forming mechanism might be extended to other hydroplastic materials (e.g., biopolymers) and help to yield hydroplasticity-based processing strategies.

2.
Environ Res ; 243: 117852, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38065385

RESUMO

Large quantities of sediments in urban sewer systems pose significant risk of pipe clogging and corrosion. Owing to their gel-like structure, sewer sediments have strong resistance to hydraulic shear stress. This study proposed a novel approach to weaken the erosion resistance of sewer sediments by destroying viscous gel-like biopolymers in sediments with low doses of calcium peroxide (CaO2). After treatment with 10-50 mg g-1 TS of CaO2, the critical erosion shear stress was significantly reduced by 25.7%-59.9%. The sediment aggregates gradually disintegrated into small diameter particles with increasing CaO2 dosage. Further analysis showed that the strong oxidizing and alkaline environment induced by CaO2 treatment led to cell lysis and changes in the composition and property of extracellular polymeric substances (EPS). After CaO2 treatment, aromatic proteins and humic acid-like substances associated with adhesion translocated from the inner EPS layers to outer layers while being disintegrated into small organic molecules. Concomitantly, CaO2 treatment disrupted the main functional groups (-OH, COO-, C-N, CO, and CN) in inner EPS layers, thus weakening EPS adhesion. Analysis of protein secondary structure and zeta potential reflected the reduced aggregation capacity of sediment microorganisms and loosening of sediment structure after CaO2 treatment. Thus, CaO2 treatment facilitated fragmentation and disaggregation of the gelatinous structure of sewer sediments. Such green strategy decreased the cost of sewer sediment disposal by 42.10-68.95% when compared to water flushing, and it would improve the self-cleaning capacity of sewer system and efficiency of dredging equipment.


Assuntos
Sedimentos Geológicos , Esgotos , Peróxidos , Alimentos
3.
Small ; 19(4): e2205003, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36424182

RESUMO

Two-dimensional nanofluidic membranes offer great opportunities for developing efficient and robust devices for ionic/water-nexus energy harvesting. However, low counterion concentration and long pathway through limited ionic flux restrict their output performance. Herein, it is demonstrated that rapid diffusion kinetics can be realized in two-dimensional nanofluidic membranes by introducing in-plane holes across nanosheets, which not only increase counterion concentration but also shorten pathway length through the membranes. Thus, the holey membranes exhibited an enhanced performance relative to the pristine ones in terms of osmotic energy conversion. In particular, a biomimetic multilayered membrane sequentially assembled from pristine and holey sections offers an optimized combination of selectivity and permeability, therefore generating a power density up to 6.78 W m-2 by mixing seawater and river water, superior to the majority of the state-of-the-art lamellar nanofluidic membranes. This work highlights the importance of channel morphologies and presents a general strategy for effectively improving ion transport through lamellar membranes for high-performance nanofluidic devices.

4.
Environ Res ; 232: 116422, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37327839

RESUMO

Algal blooms are regarded as a significant source of CH4 emissions. Ultrasound has been gradually employed as a fast and efficient algae removal technology in recent years. However, the changes in water environment and potential ecological effects caused by ultrasonic algae removal are not fully clear. Here, a 40-day microcosm study was performed to simulate the collapse of Microcystis aeruginosa blooms after ultrasonic treatment. The results showed that low-frequency ultrasound at 29.4 kHz for 15 min removed 33.49% of M. aeruginosa and contributed to the destruction of cell structure, but it intensified the leakage of intracellular algal organic matter and microcystins. The accelerated collapse of M. aeruginosa blooms after ultrasonication promoted the rapid formation of anaerobic and reductive methanogenesis conditions, and elevated dissolved organic carbon content. Moreover, the release of labile organics, including tyrosine, tryptophan, protein-like compositions, and aromatic proteins, was facilitated by the collapse of M. aeruginosa blooms after ultrasonic treatment, and they supported the growth of anaerobic fermentation bacteria and hydrogenotrophic Methanobacteriales. This was also demonstrated by the increase in methyl-coenzyme M reductase (mcrA) genes in sonicated algae added treatments at the end of incubation. Finally, the CH4 production in sonicated algae added treatments was 1.43-fold higher than that in non-sonicated algae added treatments. These observations suggested that ultrasound for algal bloom control potentially increased the toxicity of treated water and its greenhouse gas emissions. This study can provide new insights and guidance to evaluate environmental effects of ultrasonic algae removal.


Assuntos
Proliferação Nociva de Algas , Microcystis , Microcystis/metabolismo , Microcistinas , Metano
5.
Int J Mol Sci ; 24(14)2023 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-37511199

RESUMO

Silicosis is a refractory pneumoconiosis of unknown etiology that is characterized by diffuse lung fibrosis, and microRNA (miRNA) dysregulation is connected to silicosis. Emerging evidence suggests that miRNAs modulate pulmonary fibrosis through autophagy; however, its underlying molecular mechanism remains unclear. In agreement with miRNA microarray analysis, the qRT-PCR results showed that miR-29a-3p was significantly decreased in the pulmonary fibrosis model both in vitro and in vivo. Increased autophagosome was observed via transmission electron microscopy in lung epithelial cell models and lung tissue of silicosis mice. The expression of autophagy-related proteins LC3α/ß and Beclin1 were upregulated. The results from using 3-methyladenine, an autophagy inhibitor, or rapamycin, an autophagy inducer, together with TGF-ß1, indicated that autophagy attenuates fibrosis by protecting lung epithelial cells. In TGF-ß1-treated TC-1 cells, transfection with miR-29a-3p mimics activated protective autophagy and reduced alpha-smooth muscle actin and collagen I expression. miRNA TargetScan predicted, and dual-luciferase reporter experiments identified Akt3 as a direct target of miR-29a-3p. Furthermore, Akt3 expression was significantly elevated in the silicosis mouse model and TGF-ß1-treated TC-1 cells. The mammalian target of rapamycin (mTOR) is a central regulator of the autophagy process. Silencing Akt3 inhibited the transduction of the mTOR signaling pathway and activated autophagy in TGF-ß1-treated TC-1 cells. These results show that miR-29a-3p overexpression can partially reverse the fibrotic effects by activating autophagy of the pulmonary epithelial cells regulated by the Akt3/mTOR pathway. Therefore, targeting miR-29a-3p may provide a new therapeutic strategy for silica-induced pulmonary fibrosis.


Assuntos
MicroRNAs , Fibrose Pulmonar , Silicose , Animais , Camundongos , Autofagia/genética , Fibrose/genética , Fibrose/metabolismo , Mamíferos/metabolismo , MicroRNAs/metabolismo , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/genética , Fibrose Pulmonar/metabolismo , Dióxido de Silício/farmacologia , Silicose/etiologia , Silicose/genética , Silicose/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Humanos
6.
Mol Biotechnol ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38780825

RESUMO

Osteoporosis is a common chronic bone metabolism disorder characterized by decreased bone mass and reduced bone density in the bone tissue. Osteoporosis can lead to increased fragility of the skeleton, making it prone to brittle fractures. Osteoclasts are macrophage-like cells derived from hematopoietic stem cells, and their excessive activity in bone resorption leads to lower bone formation than absorption during bone remodeling, which is one of the important factors inducing osteoporosis. Therefore, how to inhibit osteoclast formation and reducing bone loss is an important direction for treating osteoporosis. Sophoraflavanone G, derived from Sophora flavescens Alt and Rhizoma Drynariae, is a flavonoid compound with various biological activities. However, there have been few studies on osteoporosis and osteoclasts so far. Therefore, we hypothesize that genistein G can inhibit osteoclast differentiation, alleviate bone loss phenomenon, and conduct in vitro and in vivo experiments for research and verification purposes.

7.
Heliyon ; 10(9): e29955, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38726195

RESUMO

Purpose: The study investigates the value of the BRAFV600E mutation in determining the aggressiveness of papillary thyroid cancer (PTC) and its correlation with ultrasound features. Methods: The study selected 176 patients with BRAFV600E mutation and 80 without the mutation who underwent surgery at Guangxi Medical University Cancer Hospital. Clinical and pathological data were collected, focusing on BRAFV600E mutations and associated ultrasonic features. Correlation analysis, as well as univariate and multivariate logistic regression analysis, were conducted to identify independent risk factors for BRAFV600E mutation. The results were verified using a nomogram model. Results: The analysis results indicate that the BRAFV600E mutation correlates with tumor size, nodule size, taller-than-wide shape, margin, and shape of papillary thyroid cancer. The receiver operating characteristic curve was used to analyze the diagnostic effect of these features on BRAFV600E mutation. The results showed that nodule size had the most significant area under the curve (AUC = 0.665). Univariate and multivariate logistic regression analyses revealed that taller-than-wide shape ≥1, ill-defined margin, irregular shape, nodule size (≤1.40 cm), TT4 (>98.67 nmol/L), and FT3 (<4.14 pmol/L) were independent risk factors for BRAFV600E mutation. While considering all these factors in the nomogram, the Concordance index (C-index) remained high at 0.764. This suggests that the model has a good predictive effect. Conclusion: Ultrasound features including nodule size, taller-than-wide shape ≥1, ill-defined margins, irregular shape, higher TT4 levels, and lower FT3 levels were associated with papillary thyroid cancer aggressiveness and BRAFV600E mutation.

8.
Biomed Pharmacother ; 171: 116166, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38244329

RESUMO

Osteoporosis is a systemic disease characterized by an imbalance in bone homeostasis, where osteoblasts fail to fully compensate for the bone resorption induced by osteoclasts. Corylifol A, a flavonoid extracted from Fructus psoraleae, has been identified as a potential treatment for this condition. Predictions from network pharmacology and molecular docking studies suggest that Corylifol A exhibits strong binding affinity with NFATc1, Nrf2, PI3K, and AKT1. Empirical evidence from in vivo experiments indicates that Corylifol A significantly mitigates systemic bone loss induced by ovariectomy by suppressing both the generation and activation of osteoclasts. In vitro studies further showed that Corylifol A inhibited the activation of PI3K-AKT and MAPK pathways and calcium channels induced by RANKL in a time gradient manner, and specifically inhibited the phosphorylation of PI3K, AKT, GSK3 ß, ERK, CaMKII, CaMKIV, and Calmodulin. It also diminishes ROS production through Nrf2 activation, leading to a decrease in the expression of key regulators such as NFATcl, C-Fos, Acp5, Mmp9, and CTSK that are involved in osteoclastogenesis. Notably, our RNA-seq analysis suggests that Corylifol A primarily impacts mitochondrial energy metabolism by suppressing oxidative phosphorylation. Collectively, these findings demonstrate that Corylifol A is a novel inhibitor of osteoclastogenesis, offering potential therapeutic applications for diseases associated with excessive bone resorption.


Assuntos
Reabsorção Óssea , Flavonas , Osteogênese , Feminino , Humanos , Animais , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Simulação de Acoplamento Molecular , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Osteoclastos/metabolismo , Reabsorção Óssea/metabolismo , Ovariectomia , Ligante RANK/metabolismo , Fatores de Transcrição NFATC/metabolismo , Camundongos Endogâmicos C57BL , Diferenciação Celular
9.
Environ Sci Pollut Res Int ; 30(2): 4010-4022, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35963965

RESUMO

In this study, diatomite, activated carbon, and iron-carbon (Fe-C) were used as biological carriers for the integrated fixed-film activated sludge process. Biomass, pollutant removal efficiency, and extracellular polymer were tested, and the effect of nitrogen and phosphorus removal, enzyme activity, and microbial diversity were studied after the sludge retention time was changed. The mechanism of carrier enriching microorganism and promoting pollutant degradation was studied. The results showed that the addition of these three carriers contributed to the enrichment of nitrifying bacteria in the system, and the NH4+-N removal efficiency was above 98%. Diatomite and Fe-C could improve pollutant removal by increasing the activity of the electron transfer system. The abundance of denitrogenation-related reductases and the enzymes synthesizing poly-ß-hydroxybutyrate was increased in activated carbon. The addition of Fe-C increased the abundance of denitrifying phosphate-accumulating organisms by approximately 25% and the removal efficiency of total phosphorus by 12.61-14.88% at the end of the long-term operation.


Assuntos
Poluentes Ambientais , Microbiota , Esgotos/microbiologia , Fósforo/metabolismo , Eliminação de Resíduos Líquidos/métodos , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Pós , Desnitrificação , Nitrogênio/metabolismo , Carvão Vegetal , Redes e Vias Metabólicas , Reatores Biológicos/microbiologia
10.
Water Res ; 233: 119776, 2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-36848849

RESUMO

Organic matter (OM) recovery from sewage sludge is critical for sustainable development. Extracellular organic substances (EOS) are the main organic components of sludge, and the release of EOS from sludge is usually the rate-limiting step for OM recovery. However, a poor understanding of the intrinsic characteristics of binding strength (BS) of EOS usually restricts the release of OM from sludge. To reveal the underlying mechanism that how the intrinsic characteristics of EOS limit its release, in this study, the BS of EOS in sludge was quantitatively characterised by 10 rounds of energy input (Ein) with the same magnitude per round; the corresponding changes in the main components, floc structures and rheological properties of sludge after different numbers of Ein were also explored. Results showed that relationships between the release of EOS and the main multivalent metals, median diameters, fractal dimensions, elastic modulus and viscous modulus in the linear viscoelastic region of sludge versus the number of Ein, highlighted that the power-law distribution of BS in EOS was responsible for the occurrence state of organic molecules, stability of floc structures and maintenance of rheological properties. The result of hierarchical cluster analysis (HCA) further revealed three BS levels of the EOS in sludge, indicating that the release or recovery of OM from sludge occurred in three stages. To the best of our knowledge, this is the first study that explores the release profiles of EOS in sludge by repeated Ein for assessing the BS. Our findings may provide an important theoretical basis for the development target methods about the release and recovery of OM from sludge.


Assuntos
Esgotos , Eliminação de Resíduos Líquidos , Esgotos/química , Eliminação de Resíduos Líquidos/métodos , Viscosidade , Fractais , Reologia
11.
Chemosphere ; 337: 139353, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37414297

RESUMO

This study provides a comparative investigation of phosphorus removal between anaerobic-anoxic-oxic (AAO) and high-concentration powder carrier bio-fluidized bed (HPB) in the same full-scale wastewater treatment plant. The results showed that the total phosphorus removal of HPB was 71.45%-96.71%. Compared with AAO, the total phosphorus removal of HPB can be increased by a maximum of 15.73%. The mechanisms of enhanced phosphorus removal by HPB include the followings. Biological phosphorus removal was significant. The anaerobic phosphorus release capacity of HPB was enhanced and polyphosphate (Poly-P) in the excess sludge of HPB was 1.5 times higher than that of AAO. The relative abundance of Candidatus Accumulibacter was 5 times higher than that of AAO, and oxidative phosphorylation and butanoate metabolism were enhanced. The analysis of phosphorus distribution showed that cyclone separation increased the chemical phosphorus precipitation (Chem-P) in the excess sludge by 16.96% to avoid accumulation in the biochemical tank. The phosphorus adsorbed by extracellular polymeric substance (EPS) in the recycled sludge was stripped, and the EPS bound-P in the excess sludge increased by 1.5 times. This study demonstrated the feasibility of HPB to improve the phosphorus removal efficiency for domestic wastewater.


Assuntos
Tempestades Ciclônicas , Esgotos , Esgotos/química , Pós , Fósforo/análise , Metagenômica , Matriz Extracelular de Substâncias Poliméricas/química , Desnitrificação , Reatores Biológicos , Nitrogênio/análise , Eliminação de Resíduos Líquidos/métodos
12.
Bioresour Technol ; 388: 129739, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37696333

RESUMO

This study posed a novel biomimetic flocculation approach, aiming to efficiently harvest high-quality biomass of Scenedesmus quadricauda cultured with anaerobic digestate. Here, that poly(diallyldimethylammonium chloride) (PDADMAC) could serve as mimetic silicified proteins to spontaneously incorporate nanosilica onto microalgal cells, imparting diatom-like characteristics to S. quadricauda. Compared to the exponential growth phase (day 3), the highest harvesting efficiency (93.49%) was obtained at a lower dosage of PDADMAC (5 mg/g) in the stationary phase (day 6), which was attributed to changes in properties and composition of microalgal LB-EPS. On day 6, the hydrophobic functional groups in LB-EPS provided more binding sites during the flocculation process and formed a network structure of microalgal cells-flocculants-nanosilica. The resulting larger and more stable biomimetic silica shell promoted microalgal flocculation and sedimentation. Compared to conventional harvesting methods (centrifugation, polyacrylamide, alkaline flocculation), this method had the minimal negative impact on harvested biomass, with 9.95% of cell membranes damaged.


Assuntos
Microalgas , Biomassa , Floculação
13.
Sci Total Environ ; 841: 156666, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35705129

RESUMO

This study provides a side-by-side comparative investigation between the full-scale conventional activated sludge (CAS) and the high-concentration powder carrier bio-fluidized bed (HPB) processes. The results showed that the HPB total nitrogen removal efficiency increased by 10.86 % more than CAS. The anammox pathway increased by 6.92 %, while the simultaneous nitrification-denitrification pathway increased by 4.27 %. Also, the effluent's total nitrogen of the HPB process was stabilized below 10 mg/L, which can withstand the impact of industrial wastewater better. More energy and substance (protein) were consumed to attach to the carriers and resist external selective pressure to produce extracellular polymeric substance rather than sludge production in the HPB process. For a 10,000 m3/d HPB wastewater treatment plant, lowering the total nitrogen and sludge production saved $110,369.64 in annual operating costs.


Assuntos
Nitrogênio , Esgotos , Reatores Biológicos , Desnitrificação , Matriz Extracelular de Substâncias Poliméricas/metabolismo , Metagenômica , Nitrificação , Nitrogênio/metabolismo , Oxirredução , Águas Residuárias
14.
Chemosphere ; 307(Pt 2): 135827, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35944692

RESUMO

Actual low-C/N domestic wastewater was treated using the high-concentration powder carrier bio-fluidized bed (HPB) process comparing diatomite and Fe-C as the carriers. The total nitrogen removal efficiencies were increased from 50.08% to 65.40% and 78.58%, respectively. The diatomite HPB process increased the relative abundance of autotrophic N-cycle bacteria to more than twofold and the sludge size. Therefore, the contributions for nitrogen removal by anammox and simultaneous nitrification-denitrification were increased. The Fe-C HPB process improved the nitrogen removal efficiency mainly by increasing the biodegradability and activities of electron transfer system and key enzymes. The key device (hydrocyclone separator) of the HPB process significantly improved the recovery efficiency of the carriers. It also improved the capacity of microbial aggregations for adsorbing pollutants. Furthermore, it reduced the relative abundance of filamentous bacteria. This study demonstrated the feasibility and mechanism of the HPB process for improving the nitrogen removal efficiency for low-C/N wastewater.


Assuntos
Poluentes Ambientais , Águas Residuárias , Bactérias , Reatores Biológicos/microbiologia , Desnitrificação , Terra de Diatomáceas , Nitrificação , Nitrogênio , Oxirredução , Pós , Esgotos/microbiologia
15.
ACS Omega ; 7(16): 13853-13860, 2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35559176

RESUMO

Macroporous structures can be developed within polyelectrolyte multilayer films for efficient drug loading, but these structures tend to collapse or fracture during conventional drying procedures. Herein, a facile dehydrating method for macroporous polyelectrolyte multilayer films is proposed using solvent exchange to ethanol and then spontaneous evaporation. During these processes, the collapse of the macroporous structures can be effectively avoided, which can be ascribed to a combined effect of two factors. On one hand, capillary pressure during ethanol evaporation is relatively small since the surface tension of ethanol is much lower than that of water. On the other hand, solvent exchange suppresses the interdiffusion of polyelectrolytes and substantially increases the mechanical strength of the macroporous films, more than three orders of magnitude, making the pore walls highly tolerant of the capillary pressure. The stability of macroporous polyelectrolyte films to ethanol enables the repeated wicking from the ethanol solution of drugs, leading to a higher loading beyond previous studies. Such a high loading is favorable for the long-term release of drugs from the surfaces of modified substrates and maintaining a local drug concentration above the minimum effective concentration.

16.
Bioresour Technol ; 351: 127015, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35306133

RESUMO

The nitrogen removal mechanism of the high concentration powder carrier bio-fluidized bed (HPB) process was investigated with actual domestic wastewater. The micron-size (10-70 µm) powder carriers were diatomite and Fe-C. Results showed diatomite enriched the relative abundances of ammonia-oxidizing bacteria and nitrite-oxidizing bacteria, accordingly increasing the rate of nitrification. Even a 100% increase of genes associated with the ammonia oxidation was achieved. Fe-C enhanced the rate of substrate utilization mainly by increasing the activity of the electron transfer system. Hydrocyclone separator, as a key device of HPB, was able to recover the carriers with high efficiency (recovery efficiency of 72.66 ─ 82.50% after 75 days), thus, indirectly improving the functionality of the carriers. Furthermore, it could renew the surface of microbial aggregations, consequently improving the adsorption capacity to substrates. HPB could provide the feasibility of shortening the hydraulic retention time and expanding the capacity of wastewater treatment plants.


Assuntos
Reatores Biológicos , Purificação da Água , Amônia , Reatores Biológicos/microbiologia , Nitrificação , Nitrogênio , Oxirredução , Pós , Águas Residuárias
17.
Am J Sports Med ; 50(11): 2961-2971, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35914270

RESUMO

BACKGROUND: Individuals with anterior cruciate ligament (ACL) reconstruction (ACLR) are a population that has a higher risk for ACL injury compared with the general population. To reduce the reinjury rate and improve the rehabilitation outcome after ACLR, risk factors for ACL injury have to be addressed. PURPOSE: To compare the knee biomechanics during side-cutting and isokinetic strength of the thigh muscle of the reconstructed leg with those of the contralateral leg and healthy controls and investigate the knee movement asymmetries in individuals with ACLR. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 16 participants with ACLR (ACLR group; 11.8 ± 1.1 months after reconstruction) and 16 healthy controls (control group) were recruited. Landmark coordinates and ground-reaction forces during side-cutting and isokinetic strength of hamstring and quadriceps were collected. Two-way analysis of variance with the mixed design was performed to compare each dependent variable between groups and across legs. RESULTS: The reconstructed leg had a significantly smaller knee flexion angle (P = .004) and less quadriceps strength (P = .003) than the contralateral leg. The knee extension moment and knee external rotation angle were decreased compared with both the contralateral leg (P = .001, P = .003, respectively) and the healthy control leg (P = .001, P = .001, respectively). The ACLR group showed greater knee abduction angles (P = .004) and smaller knee external rotation moments (P = .006) than the control group. The ACLR group also demonstrated greater asymmetries of knee flexion angle (P = .015), knee external rotation angle (P = .001), knee extension moment (P = .013), knee abduction moment (P = .001), and quadriceps strength (P = .046) than the control group. CONCLUSION: Knee biomechanics in the leg with ACLR were altered mainly in the sagittal plane during side-cutting compared with the contralateral leg. The altered movement patterns between the ACLR and control groups were primarily observed in the frontal and transverse planes. The ACLR group also demonstrated greater asymmetries of sagittal knee movement and concentric quadriceps strength than the control group. CLINICAL RELEVANCE: Individuals with ACLR showed different alterations in the reconstructed and contralateral leg compared with healthy controls. These results suggest that rehabilitation programs after ACLR should further focus on restoring the knee flexion angle and quadriceps strength. Injury prevention programs need to be further targeted in the altered movement patterns observed between the ACLR and the healthy groups.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/reabilitação , Fenômenos Biomecânicos , Humanos , Joelho/cirurgia , Articulação do Joelho/fisiologia , Articulação do Joelho/cirurgia , Força Muscular/fisiologia , Músculo Quadríceps/fisiologia
18.
Bioengineering (Basel) ; 9(11)2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36421117

RESUMO

There is little known about kinetic changes in anterior cruciate ligament deficiency (ACLD) combined with meniscal tears during jogging. Therefore, 29 male patients with injured ACLs and 15 healthy male volunteers were recruited for this study to investigate kinetic abnormalities in male patients after ACL deficiency combined with a meniscal injury during jogging. Based on experimental data measured by an optical tracking system, a subject-specific musculoskeletal model was employed to estimate the tibiofemoral joint kinetics during jogging. Between-limb and interpatient differences were compared by the analysis of variance. The results showed that decreased knee joint forces and moments of both legs in ACLD patients were detected during the stance phase compared to the control group. Meanwhile, compared with ACLD knees, significantly fewer contact forces and flexion moments in ACLD combined with lateral and medial meniscal injury groups were found at the mid-stance, and ACLD with medial meniscal injury group showed a lower axial moment in the loading response (p < 0.05). In conclusion, ACLD knees exhibit reduced tibiofemoral joint forces and moments during jogging when compared with control knees. A combination of meniscus injuries in the ACLD-affected side exhibited abnormal kinetic alterations at the loading response and mid-stance phase.

19.
J Rehabil Med ; 52(3): jrm00035, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32152642

RESUMO

OBJECTIVE: To examine the effects of combining whey protein isolate supplement with preoperative isokinetic eccentric training on quadriceps mass and strength following anterior cruciate ligament rupture. DESIGN: Randomized controlled trial. SUBJECTS: A total of 37 male subjects with anterior cruciate ligament rupture. METHODS: Participants were randomly assigned to an isokinetic eccentric training group (n = 19) or an isokinetic eccentric training + whey protein isolate group (n = 18). Both groups received isokinetic eccentric training for 6 weeks. The isokinetic eccentric training + whey protein isolate group received 22 g whey protein isolate daily. RESULTS: After the intervention, the cross-sectional area of the affected quadriceps had increased only in the isokinetic eccentric training + whey protein isolate group (7.6 ± 6.8%; p = 0.012), whereas there was no change in the isokinetic eccentric training group (3.7 ± 4.5%; p = 0.11). Both groups showed increased quadriceps strength; however, there were no further effects for the isokinetic eccentric training + whey protein isolate group. Lysholm and IKDC 2000 knee function scores increased only in the isokinetic eccentric training + whey protein isolate group (p < 0.01). CONCLUSION: Although the study showed numerically better outcomes for the combination of whey protein isolate supplement with isokinetic eccentric training compared with isokinetic eccentric training alone, no statistically significant differences were demonstrated between the groups.


Assuntos
Lesões do Ligamento Cruzado Anterior/terapia , Ligamento Cruzado Anterior/efeitos dos fármacos , Músculo Quadríceps/fisiopatologia , Ensino/tendências , Proteínas do Soro do Leite/uso terapêutico , Adulto , Ligamento Cruzado Anterior/patologia , Humanos , Masculino , Proteínas do Soro do Leite/farmacologia
20.
Orthop J Sports Med ; 8(5): 2325967120919058, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32548180

RESUMO

BACKGROUND: Patients with anterior cruciate ligament-deficient (ACLD) knees with medial meniscal posterior horn tears (MMPHTs) have been reported to demonstrate a combined stiffening and pivot-shift gait pattern compared with healthy controls. Movement asymmetries are implicated in the development and progression of osteoarthritis. PURPOSE: To investigate the knee kinematics and kinetic asymmetries in ACLD patients with (ACLD + MMPHT group) and without (ACLD group) MMPHTs while walking on level ground. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: A total of 15 patients with isolated unilateral ACL ruptures, 10 with unilateral ACL ruptures and MMPHTs, and 22 healthy controls underwent gait testing between January 2014 and December 2016. Between-leg differences (BLDs) in knee kinematics and kinetics were compared among participants in all groups. RESULTS: The ACLD + MMPHT group demonstrated significantly greater BLDs in knee moments in the sagittal plane during the loading response phase than the ACLD and control groups. Compared with the control group, the ACLD and ACLD + MMPHT groups demonstrated significantly greater BLDs in knee angles in the sagittal plane during the midstance and terminal stance phases. Compared with the control group, significantly greater BLDs in knee rotation moments were found throughout the stance phase in both the ACLD and the ACLD + MMPHT groups. BLDs in lateral ground-reaction forces (GRFs) in the ACLD + MMPHT and ACLD groups were both significantly greater than the control group during the loading response phase. BLDs in anterior GRFs in the ACLD + MMPHT and ACLD groups were both significantly greater than the control group during the loading response phase. Only the ACLD + MMPHT group demonstrated greater BLDs in vertical GRFs than the control group during the loading response phase, while no significant differences were observed between the ACLD and control groups. CONCLUSION: The ACLD + MMPHT group demonstrated significantly more knee flexion moment asymmetries than the ACLD and control groups during the loading response phase. Both the ACLD + MMPHT and the ACLD groups demonstrated significant knee angle and moment asymmetries in the sagittal plane during the terminal stance phase than the control group. Both the ACLD + MMPHT and the ACLD groups demonstrated knee rotation moment asymmetries during the midstance and terminal stance phases compared with the control group. A rehabilitation program for ACLD patients both with and without MMPHTs should take into consideration these asymmetric gait patterns.

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