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1.
Nature ; 606(7913): 305-312, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35676429

RESUMEN

Li- and Mn-rich (LMR) cathode materials that utilize both cation and anion redox can yield substantial increases in battery energy density1-3. However, although voltage decay issues cause continuous energy loss and impede commercialization, the prerequisite driving force for this phenomenon remains a mystery3-6 Here, with in situ nanoscale sensitive coherent X-ray diffraction imaging techniques, we reveal that nanostrain and lattice displacement accumulate continuously during operation of the cell. Evidence shows that this effect is the driving force for both structure degradation and oxygen loss, which trigger the well-known rapid voltage decay in LMR cathodes. By carrying out micro- to macro-length characterizations that span atomic structure, the primary particle, multiparticle and electrode levels, we demonstrate that the heterogeneous nature of LMR cathodes inevitably causes pernicious phase displacement/strain, which cannot be eliminated by conventional doping or coating methods. We therefore propose mesostructural design as a strategy to mitigate lattice displacement and inhomogeneous electrochemical/structural evolutions, thereby achieving stable voltage and capacity profiles. These findings highlight the significance of lattice strain/displacement in causing voltage decay and will inspire a wave of efforts to unlock the potential of the broad-scale commercialization of LMR cathode materials.

2.
Pestic Biochem Physiol ; 203: 106009, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39084775

RESUMEN

Fall armyworm, Spodoptera frugiperda (J. E. Smith), is a widely recognized global agricultural pest that has significantly reduced crop yields all over the world. S. frugiperda has developed resistance to various insecticides. Insect cytochrome P450 monooxygenases (CYPs or P450s) play an important role in detoxifying insecticides, leading to increased resistance in insect populations. However, the function of the specific P450 gene for lambda-cyhalothrin resistance in S. frugiperda was unclear. Herein, the expression patterns of 40 P450 genes in the susceptible and lambda-cyhalothrin-resistant populations were analyzed. Among them, CYP321A7 was found to be overexpressed in the resistant population, specifically LRS (resistance ratio = 25.38-fold) derived from a lambda-cyhalothrin-susceptible (SS) population and FLRS (a population caught from a field, resistance ratio = 63.80-fold). Elevated enzyme activity of cytochrome P450 monooxygenases (P450s) was observed for LRS (2.76-fold) and the FLRS (4.88-fold) as compared to SS, while no significant differences were observed in the activities of glutathione S-transferases and esterases. Furthermore, the knockdown of CYP321A7 gene by RNA interference significantly increased the susceptibility to lambda-cyhalothrin. Remarkably, the knockdown of CYP321A7 reduced the enzymatic activity of P450 by 43.7%, 31.9%, and 22.5% in SS, LRS, and FLRS populations, respectively. Interestingly, fourth-instar larvae treated with lambda-cyhalothrin at the LC30 dosage had a greater mortality rate due to RNA interference-induced suppression of CYP321A7 (with increases of 61.1%, 50.0%, and 45.6% for SS, LRS, and FLRS populations, respectively). These findings suggest a link between lambda-cyhalothrin resistance and continual overexpression of CYP321A7 in S. frugiperda larvae, emphasizing the possible importance of CYP321A7 in lambda-cyhalothrin detoxification in S. frugiperda.


Asunto(s)
Sistema Enzimático del Citocromo P-450 , Resistencia a los Insecticidas , Insecticidas , Nitrilos , Piretrinas , Spodoptera , Animales , Piretrinas/farmacología , Piretrinas/toxicidad , Spodoptera/efectos de los fármacos , Spodoptera/genética , Nitrilos/toxicidad , Nitrilos/farmacología , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Insecticidas/farmacología , Insecticidas/toxicidad , Resistencia a los Insecticidas/genética , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Interferencia de ARN , Inactivación Metabólica , Larva/efectos de los fármacos , Larva/genética
3.
Sensors (Basel) ; 23(11)2023 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-37300063

RESUMEN

Compared to fixed orthodontic appliances with brackets, thermoplastic invisible orthodontic aligners offer several advantages, such as high aesthetic performance, good comfort, and convenient oral health maintenance, and are widely used in orthodontic fields. However, prolonged use of thermoplastic invisible aligners may lead to demineralization and even caries in most patients' teeth, as they enclose the tooth surface for an extended period. To address this issue, we have created PETG composites that contain piezoelectric barium titanate nanoparticles (BaTiO3NPs) to obtain antibacterial properties. First, we prepared piezoelectric composites by incorporating varying amounts of BaTiO3NPs into PETG matrix material. The composites were then characterized using techniques such as SEM, XRD, and Raman spectroscopy, which confirmed the successful synthesis of the composites. We cultivated biofilms of Streptococcus mutans (S. mutans) on the surface of the nanocomposites under both polarized and unpolarized conditions. We then activated piezoelectric charges by subjecting the nanocomposites to 10 Hz cyclic mechanical vibration. The interactions between the biofilms and materials were evaluated by measuring the biofilm biomass. The addition of piezoelectric nanoparticles had a noticeable antibacterial effect on both the unpolarized and polarized conditions. Under polarized conditions, nanocomposites demonstrated a greater antibacterial effect than under unpolarized conditions. Additionally, as the concentration of BaTiO3NPs increased, the antibacterial rate also increased, with the surface antibacterial rate reaching 67.39% (30 wt% BaTiO3NPs). These findings have the potential for application in wearable, invisible appliances to improve clinical services and reduce the need for cleaning methods.


Asunto(s)
Nanocompuestos , Streptococcus mutans , Humanos , Biopelículas , Antibacterianos/farmacología , Antibacterianos/química , Nanocompuestos/química
4.
Angew Chem Int Ed Engl ; 62(10): e202218595, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36592112

RESUMEN

The cathode materials work as the host framework for both Li+ diffusion and electron transport in Li-ion batteries. The Li+ diffusion property is always the research focus, while the electron transport property is less studied. Herein, we propose a unique strategy to elevate the rate performance through promoting the surface electric conductivity. Specifically, a disordered rock-salt phase was coherently constructed at the surface of LiCoO2 , promoting the surface electric conductivity by over one magnitude. It increased the effective voltage (Veff ) imposed in the bulk, thus driving more Li+ extraction/insertion and making LiCoO2 exhibit superior rate capability (154 mAh g-1 at 10 C), and excellent cycling performance (93 % after 1000 cycles at 10 C). The universality of this strategy was confirmed by another surface design and a simulation. Our findings provide a new angle for developing high-rate cathode materials by tuning the surface electron transport property.

5.
Small ; 18(6): e2103499, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34850552

RESUMEN

Lithium-excess manganese layered oxide Li2 MnO3 , attracts much attention as a cathode in Li-ion batteries, due to the low cost and the ultrahigh theoretical capacity (≈460 mA h g-1 ). However, it delivers a low reversible practical capacity (<200 mA h g-1 ) due to the irreversible oxygen redox at high potentials (>4.5 V). Herein, heavy fluorination (9.5%) is successfully implemented in the layered anionic framework of a Li-Mn-O-F (LMOF) cathode through a unique ion-exchange route. F substitution with O stabilizes the layered anionic framework, completely inhibits the O2 evolution during the first cycle, and greatly enhances the reversibility of oxygen redox, delivering an ultrahigh reversible capacity of 389 mA h g-1 , which is 85% of the theoretical capacity of Li2 MnO3 . Moreover, it also induces a thin spinel shell coherently forming on the particle surface, which greatly improves the surface structure stability, making LMOF exhibit a superior cycling stability (a capacity retention of 91.8% after 120 cycles at 50 mA g-1 ) and excellent rate capability. These findings stress the importance of stabilizing the anionic framework in developing high-performance low-cost cathodes for next-generation Li-ion batteries.

6.
Minim Invasive Ther Allied Technol ; 31(2): 262-268, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32677486

RESUMEN

BACKGROUND: Using self-gripping mesh eliminates the need for additional mechanical fixation in laparoscopic groin hernia repair when surgeons plan to fix it. However, the mesh's 'self-gripping' characteristic makes it much more difficult to unfold and place. Here, the novel "Swiss-roll" placement method of folding self-gripping mesh is introduced and compared to the common folding placement method. MATERIAL AND METHODS: The cohort of this prospective randomized controlled study included 100 patients who underwent transabdominal preperitoneal (TAPP) groin hernia repair in the Department of Hernia and Abdominal Wall Surgery of Shanghai East Hospital between January and December 2018. The patients were randomly assigned to the "Swiss-roll" folding group or the common folding group. The time required for mesh placement, total surgical duration, and the incidences of postoperative pain and complications were compared. RESULTS: The times required for mesh placement in the "Swiss-roll" and common folding groups were 155.10 ± 48.66 and 202.80 ± 61.05 sec, respectively. The "Swiss-roll" folding method significantly shortened the time required for mesh placement (p = 0.000). There were no significant differences in total surgical duration and the incidences of postoperative pain and complications between the two groups. CONCLUSIONS: The "Swiss-roll" folding method facilitates self-gripping mesh placement without increasing the incidence of complications and recurrences in TAPP.


Asunto(s)
Hernia Inguinal , Laparoscopía , China , Hernia Inguinal/cirugía , Herniorrafia , Humanos , Estudios Prospectivos , Recurrencia , Mallas Quirúrgicas
7.
Ann Plast Surg ; 87(5): 580-588, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34139739

RESUMEN

BACKGROUND: The advantages of good biocompatibility, low degradation and low antigenicity of collagen, and the osteogenic differentiation characteristics of bone mesenchymal stem cells (BMSCs) were used to promote the recovery of bone defects using partially deproteinized bone (PDPB) by bone tissue engineering (BTE). METHODS: The BMSCs were identified by examining their potential for osteogenic, lipogenic, and chondrogenic differentiation. The prepared pure PDPB was ground into bone blocks 4 × 2 × 2 mm in size, which were divided into the following groups: PDPB group, PDPB + collagen group, PDPB + collagen + BMSC group, PDPB with a composite collagen nanofilm, and BMSCs injected into the tail vein. At 2, 4, 6, and 8 weeks after surgery, the effects of the implants in the different groups on bone defect repair were continuously and dynamically observed through x-ray examination, gross specimen observation, histological evaluation, and microvascularization detection. RESULTS: Postoperative x-ray examination and gross specimen observation revealed that, after 4 to 8 weeks, the external contour of the graft was gradually weakened, and the transverse comparison showed that the absorption of the graft and fusion of the defect were more obvious in PDPB + collagen + BMSC group than in PDPB group and PDPB + collagen group, and the healing was better (P < 0.05). Hematoxylin and eosin staining of histological sections showed very active proliferation of trabecular hematopoietic cells in groups PDPB + collagen + BMSC and PDPB + collagen. Masson's trichrome staining for evaluation of bone defect repair showed that the mean percent area of collagen fibers was greater in PDPB + collagen + BMSC group than in the PDPB group, with degradation of the scaffold material and the completion of repair. Immunofluorescence staining showed significantly enhanced expression of the vascular marker CD31 in group C (P < 0.05). CONCLUSIONS: The proposed hybrid structure of the collagen matrix and PDPB provides an ideal 3-dimensional microenvironment for patient-specific BTE and cell therapy applications. The results showed that collagen appeared to regulate MSC-mediated osteogenesis and increase the migration and invasion of BMSCs. The combination of collagen nanofilm and biological bone transplantation with BMSC transplantation enhanced the proliferation and potential of the BMSCs for bone regeneration, successfully promoting bone repair after implantation at the defect site. This method may provide a new idea for treating clinical bone defects through BTE.


Asunto(s)
Regeneración Ósea , Células Madre Mesenquimatosas , Ingeniería de Tejidos , Animales , Colágeno , Osteogénesis , Ratas , Andamios del Tejido
8.
Small ; 15(47): e1904545, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31588653

RESUMEN

Aqueous Zn-MnO2 batteries using mild electrolyte show great potential in large-scale energy storage (LSES) application, due to high safety and low cost. However, structure collapse of manganese oxides upon cycling caused by the conversion mechanism (e.g., from tunnel to layer structures for α-, ß-, and γ-phases) is one of the most urgent issues plaguing its practical applications. Herein, to avoid the phase conversion issue and enhance battery performance, a structurally robust novel phase of manganese oxide MnO2 H0.16 (H2 O)0.27 (MON) nanosheet with thickness of ≈2.5 nm is designed and synthesized as a promising cathode material, in which a nanosheet structure combined with a novel H+ /Zn2+ synergistic intercalation mechanism is demonstrated and evidenced. Accordingly, a high-performance Zn/MON cell is achieved, showing a high energy density of ≈228.5 Wh kg-1 , impressive cyclability with capacity retention of 96% at 0.5 C after 300 cycles, as well as exhibiting rate performance of 115.1 mAh g-1 at current rate of 10 C. To the best current knowledge, this H+ /Zn2+ synergistic intercalation mechanism is first reported in an aqueous battery system, which opens a new opportunity for development of high-performance aqueous Zn ion batteries for LSES.

9.
Org Biomol Chem ; 17(22): 5509-5513, 2019 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-31112197

RESUMEN

A copper nitrate-mediated [2 + 2 + 1] cycloaddition reaction was developed for the expedient synthesis of pharmacologically interesting 3-aryl substituted isoxazolines and isoxazoles through C[double bond, length as m-dash]C bond cleavage. Copper nitrate is employed as a reaction promoter and precursor of nitrile oxides. The given approach features a new mode of cycloaddition from olefinic azlactones, copper nitrate and unsaturated compounds with wide substrate scope, good functional group tolerance and operational simplicity.

10.
Molecules ; 24(12)2019 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-31242597

RESUMEN

Colorectal cancer (CRC) is a leading cause of cancer-related deaths worldwide. Isoxazoline and isoxazole derivatives represent an important class of five-membered heterocycles, which play a pivotal role in drug discovery. In our previous study, we developed a series of isoxazole derivatives with an efficient method. In this study, we evaluated their effects on tumor cell growth. HCT116 cells were treated with isoxazole derivatives; an cholecystokinin octapeptide (CCK-8) assay was used to calculate the IC50 (half maximal inhibitory concentration) of each derivative. Compound SHU00238, which was obtained by the copper nitrate-mediated [2+2+1] cycloaddition reaction of olefinic azlactone with naphthalene-1,4-dione, has a lower IC50; we analyzed its inhibitory activity in further assays. Cell apoptosis was estimated by flow cytometry analysis in vitro. SHU00238 injection was used to treat tumor-bearing mice. We found that SHU00238 suppressed cell viability and promoted cell apoptosis in vitro. SHU00238 treatment significantly inhibited colonic tumor growth in vivo. Furthermore, we compared the miRNAs expression changes in HCT116 cells before and after SHU00238 treatment. MiRNA profiling revealed that SHU00238 treatment affected cell fate by regulating a set of miRNAs. In conclusion, SHU00238 impedes CRC tumor cell proliferation and promotes cell apoptosis by miRNAs regulation.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias Colorrectales/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Isoxazoles/farmacología , MicroARNs/genética , Animales , Antineoplásicos/química , Apoptosis , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Biología Computacional , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Perfilación de la Expresión Génica , Humanos , Isoxazoles/química , Ratones , Estructura Molecular , Interferencia de ARN , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Eur J Nutr ; 57(3): 1157-1168, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28324208

RESUMEN

PURPOSE: This study examined the effect of soy proteins with depletion of different subunits of the two major storage proteins, ß-conglycinin and glycinin, on hepatic lipids and proteins involved in lipid metabolism in rats, since the bioactive component of soy responsible for lipid-lowering is unclear. METHODS: Weanling Sprague Dawley rats were fed diets containing either 20% casein protein in the absence (casein) or presence (casein + ISF) of isoflavones or 20% alcohol-washed soy protein isolate (SPI) or 20% soy protein concentrates derived from a conventional (Haro) or 2 soybean lines lacking the α' subunit of ß-conglycinin and the A1-3 (1TF) or A1-5 (1a) subunits of glycinin. After 8 weeks, the rats were necropsied and liver proteins and lipids were extracted and analysed. RESULTS: The results showed that soy protein diets reduced lipid droplet accumulation and content in the liver compared to casein diets. The soy protein diets also decreased the level of hepatic mature SREBP-1 and FAS in males, with significant decreases in diets 1TF and 1a compared to the casein diets. The effect of the soy protein diets on female hepatic mature SREBP-1, FAS, and HMGCR was confounded since casein + ISF decreased these levels compared to casein alone perhaps muting the decrease by soy protein. A reduction in both phosphorylated and total STAT3 in female livers by ISF may account for the gender difference in mechanism in the regulation and protein expression of the lipid modulators. CONCLUSIONS: Overall, soy protein deficient in the α' subunit of ß-conglycinin and A1-5 subunits of glycinin maintain similar hypolipidemic function compared to the conventional soy protein. The exact bioactive component(s) warrant identification.


Asunto(s)
Antígenos de Plantas/uso terapéutico , Globulinas/uso terapéutico , Hiperlipidemias/prevención & control , Metabolismo de los Lípidos , Hígado/metabolismo , Proteínas de Vegetales Comestibles/uso terapéutico , Subunidades de Proteína/uso terapéutico , Proteínas de Almacenamiento de Semillas/uso terapéutico , Proteínas de Soja/uso terapéutico , Animales , Antígenos de Plantas/química , Antígenos de Plantas/genética , Antígenos de Plantas/metabolismo , Caseínas/efectos adversos , Dieta Alta en Grasa/efectos adversos , Femenino , Alimentos Modificados Genéticamente , Globulinas/química , Globulinas/genética , Globulinas/metabolismo , Hiperlipidemias/etiología , Hiperlipidemias/metabolismo , Hiperlipidemias/patología , Gotas Lipídicas/metabolismo , Gotas Lipídicas/patología , Hígado/enzimología , Hígado/patología , Masculino , Fosforilación , Proteínas de Vegetales Comestibles/química , Proteínas de Vegetales Comestibles/genética , Proteínas de Vegetales Comestibles/metabolismo , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/metabolismo , Procesamiento Proteico-Postraduccional , Subunidades de Proteína/química , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Ratas Sprague-Dawley , Factor de Transcripción STAT3/metabolismo , Proteínas de Almacenamiento de Semillas/química , Proteínas de Almacenamiento de Semillas/genética , Proteínas de Almacenamiento de Semillas/metabolismo , Caracteres Sexuales , Proteínas de Soja/química , Proteínas de Soja/genética , Proteínas de Soja/metabolismo , Vacuolas/patología , Destete
13.
Chemistry ; 21(24): 8867-73, 2015 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-25955825

RESUMEN

New BN-embedded, thiophene-fused, polycyclic aromatic compounds with planar geometry were designed and synthesized. The molecules showed excellent stability and chemical robustness. Postfunctionalization on this skeleton was demonstrated with a series of electrophilic bromination, palladium-catalyzed cross-coupling, and Knoevenagel condensation reactions. The π skeleton remained intact during these late-stage transformations. The optical and electronic properties have been well tuned through incorporation of electron-rich and -deficient groups on the backbone. This work shows the great advantage of the postfunctionalization strategy on BN-containing polycyclic aromatic compounds for fast diversification and materials screening.

14.
Zool Stud ; 62: e5, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39355318

RESUMEN

larifying the effects of continuous cotton cropping (CC) on soil biological communities is essential for maintaining agricultural productivity. In this study, high-throughput sequencing was used to study the effects of different CC durations (0-yr, 5-yr, 10-yr, 15-yr, 20-yr, and 25-yr CC treatments) on soil microbial and nematode communities. The results showed that the dominant bacterial phyla were Actinobacteria and Proteobacteria, and the dominant nematode genus was Helicotylenchus in all CC treatments. The richness indexes (ACE and Chao1 index) and diversity index (Shannon index) of bacterial and nematode communities were the highest in the 15-yr and 10-yr CC treatments, respectively. Bacterial community was significantly correlated with soil pH and available potassium (AK), and nematode abundance was significantly correlated with microbial biomass carbon (MBC). Soil bacterial PICRUSt analysis results showed that carbon metabolism and amino acid metabolism were the main metabolic functions of bacteria in the CC treatments. The composition and diversity of soil nematode communities were significantly related to the structure of soil bacterial communities, and the niche breadth of soil bacteria was negatively correlated with that of nematodes. Panagrolaimus and Acrobeles were the main genera of bacterialfeeding nematodes affecting bacterial communities, and their relative abundances were significantly positively correlated with the relative abundance of bacterial communities. Overall, long-term (10-15 years) continuous cotton cropping negatively impacts soil biota and the microecological environment of cotton fields in arid regions.

15.
ACS Omega ; 9(24): 26596-26606, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38911806

RESUMEN

Developing high-performance solvents for extraction and optimizing process technologies is crucial for efficient extractive distillation (ED) separation of azeotrope mixtures. In this paper, computer-aided screening was used to study the ED of azeotrope mixtures in ethyl acetate and ethanol systems using organic solvent dimethyl sulfoxide (DMSO) and ionic liquid (IL) ([EMIM][Ac]). The structural relationship between the ILs and the azeotrope mixture was analyzed by σ-profile, molecular surface electrostatic potential, interaction energy, and separation gradient. Subsequently, process simulation was carried out using Aspen Plus software and global optimization was performed with genetic algorithm, which found that both traditional organic solvents and ILs have good separation effects. But considering the high volatility of organic solvents and low saturation vapor pressure of ILs, it is considered to combine them to further explore the cost and carbon emission advantages in extractive distillation separation. Compared with pure organic solvent and pure ILs separation processes, the TAC of the process using an IL-based mixed solvent process decreased by 5.11 and 21.98%, respectively. The carbon emissions of the mixed extractant process were slightly higher than those of the pure organic solvent process, but the addition of ILs made very little volatilization of organic solvents, saving a charge for extractant use. By improving the process, waste heat is effectively recovered, which can save most of the utility engineering costs, and compared with the previous process, the total alkali consumption and carbon dioxide emissions are reduced by 9.43 and 27.17%, respectively. This exploration provides a theoretical reference for the development application and industrial research of ED processes using IL-based mixed solvents.

16.
Adv Mater ; 36(27): e2403307, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38630907

RESUMEN

Lithium-rich layer oxide cathodes are promising energy storage materials due to their high energy densities. However, the oxygen loss during cycling limits their practical applications. Here, the essential role of Li content on the topological inhibition of oxygen loss in lithium-rich cathode materials and the relationship between the migration network of oxygen ions and the transition metal (TM) component are revealed. Utilizing first-principles calculations in combination with percolation theory and Monte Carlo simulations, it is found that TM ions can effectively encage the oxidized oxygen species when the TM concentration in TM layer exceeds 5/6, which hinders the formation of a percolating oxygen migration network. This study demonstrates the significance of rational compositional design in lithium-rich cathodes for effectively suppressing irreversible oxygen release and enhancing cathode cycling performance.

17.
Orthop Surg ; 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-39219035

RESUMEN

BACKGROUND: Early femoral neck shortening after femoral neck system (FNS) fixation for displaced femoral neck fractures can occur in 22.3%-39.1% of cases, leading to decreased hip joint function. This study aimed to investigate the effectiveness of using an anti-shortening screw (ASS) in FNS fixation to prevent postoperative femoral neck shortening in displaced femoral neck fractures. METHODS: We retrospectively analyzed 106 cases of displaced femoral neck fractures treated with FNS at the Hospital from April 2020 to April 2023. Patients were divided into two groups based on the use of an ASS: the traditional group and the ASS group, each consisting of 53 cases. The ASS group was age-matched with the traditional group treated during the same period without an ASS. The study variables included age, sex, body mass index (BMI), smoking and drinking history, injury mechanism, side of injury, fracture type, surgical time, intraoperative blood loss, Harris Hip Score (HHS) at the final follow-up, radiographic assessment (femoral neck shortening), and complications (infection, femoral head necrosis, nonunion, and secondary surgery). Statistical analysis was performed using SPSS software, with continuous and categorical variables analyzed using appropriate parametric (t-test) and nonparametric (Mann-Whitney U test) tests, and chi-square or Fisher's exact tests, respectively. A p-value <0.05 was considered significant. RESULTS: There were no significant differences in background characteristics between the traditional and ASS groups. The shortening distance at postoperative day 1 did not differ significantly between the two groups (0 vs. 0 mm, p = 0.120). However, at 1, 3 months, and 1 year postoperatively, the femoral neck shortening in the ASS group was significantly less than that in the traditional group (1 month: 2.3 vs. 3.1 mm, p = 0.007; 3 months: 2.6 vs. 3.5 mm, p = 0.005; 1 year: 2.6 vs. 3.5 mm, p = 0.002). The ASS group also had a significantly lower shortening distance during the fracture healing process (0.9 vs. 2.7 mm, p = 0.005). The incidence of moderate to severe shortening (≥5 mm) at 1 year postoperatively was lower in the ASS group compared with the traditional group (15.1% vs. 37.7%, p = 0.001). The ASS group had a longer surgical time (63.0 ± 13.4 vs. 73.0 ± 23.2 min, p = 0.008) and a higher HHS (90.7 vs. 94.8, p = 0.008). There was no significant difference in fracture healing time or postoperative complications between the two groups. The traditional group had 3.8% cutouts, 7.5% nonunions, 5.7% avascular necrosis, and 7.5% secondary hip replacements. The ASS group saw 0% cutouts, 1.9% nonunions, 3.8% avascular necrosis, and 3.8% hip replacements. No significant differences in complication rates (p > 0.05). CONCLUSION: The use of an ASS in FNS fixation for displaced femoral neck fractures can reduce the degree of postoperative shortening and improve hip joint function.

18.
J Orthop Surg Res ; 19(1): 690, 2024 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-39456012

RESUMEN

BACKGROUND: Displaced femoral neck fractures frequently result in considerable patient morbidity, with complications such as postoperative femoral neck shortening occurring in up to 39.1% of cases. This shortening is associated with reduced hip function and mobility. The Femoral Neck System (FNS), which allows for controlled sliding to facilitate fracture reduction and healing, may mitigate these issues. However, the ideal sliding distance to balance fracture healing and minimize complications is not well defined. METHODS: We performed a retrospective cohort study of 179 patients who underwent FNS fixation for displaced femoral neck fractures at our institution from September 2019 to September 2023. Patients were categorized into three groups based on the intraoperative sliding distance allowed by the FNS: the Minimal Slide group (≤ 5 mm), the Moderate Slide group (> 5 to ≤ 10 mm), and the Extensive Slide group (> 10 to 20 mm). Primary outcomes included postoperative femoral neck shortening, the incidence of moderate to severe shortening, time to fracture union, and hip joint function as assessed by the Harris Hip Score (HHS) and the Parker Mobility Score. Secondary outcomes included complication rates such as implant cut-out, nonunion, avascular necrosis of the femoral head, and the need for secondary surgery. RESULTS: The Extensive Slide group of moderate to severe shortening at 32.31%, which was 1.59-fold and 8.88-fold that of the Moderate Slide (20.34%) and Minimal Slide group's (3.64%), respectively (P < 0.01). The sliding predominantly occurred within the first three months postoperatively and had substantially ceased by six months. At one year postoperatively, the median shortening was 2.7 mm (IQR, 0.7 to 3.5 mm) for the Minimal Slide group, a value that was notably lower compared to the 3.2 mm (IQR, 2.4 to 4.6 mm) for the Moderate Slide group and the 3.5 mm (IQR, 1.3 to 8.1 mm) for the Extensive Slide group. The average time to achieve union was similar across all groups, with no significant differences. Functional outcomes, as assessed by the Harris Hip Score (HHS) and the Parker Mobility Score, the Harris Hip Score (HHS) demonstrated statistical significance, the Parker Mobility Score did not reach statistical significance. CONCLUSIONS: Restricting FNS slide to ≤ 5 mm in surgery may reduce shortening, improve hip function, and not hinder fracture healing or implant stability. Considering the key 3-month sliding timeline postoperatively is advisable in clinical practice. Further research with a broader patient cohort is vital to confirm these findings and to anchor them in evidence-based practice.


Asunto(s)
Fracturas del Cuello Femoral , Fijación Interna de Fracturas , Humanos , Fracturas del Cuello Femoral/cirugía , Estudios Retrospectivos , Masculino , Femenino , Anciano , Persona de Mediana Edad , Fijación Interna de Fracturas/métodos , Estudios de Cohortes , Anciano de 80 o más Años , Resultado del Tratamiento , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Curación de Fractura , Cuello Femoral/cirugía , Cuello Femoral/diagnóstico por imagen , Adulto
19.
J Biomed Mater Res A ; 112(6): 941-955, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38230575

RESUMEN

Pro-inflammatory response impairs the constructive repair of abdominal wall defects after mesh implantation. Electrospinning-aid functionalization has the potential to improve the highly orchestrated response by attenuating the over-activation of foreign body reactions. Herein, we combined poly(L-lactic acid-co-caprolactone) (PLLA-CL) with gelatin proportionally via electrospinning, with Ibuprofen (IBU) incorporation to fabricate a bilayer mesh for the repair improvement. The PLLA-CL/gelatin/IBU (PGI) mesh was characterized in vitro and implanted into the rat model with a full-thickness defect for a comprehensive evaluation in comparison to the PLLA-CL/gelatin (PG) and off-the-shelf small intestinal submucosa (SIS) meshes. The bilayer PGI mesh presented a sustained release of IBU over 21 days with degradation in vitro and developed less-intensive intraperitoneal adhesion along with a histologically weaker inflammatory response than the PG mesh after 28 days. It elicited an M2 macrophage-dominant foreign body reaction within the process, leading to a pro-remodeling response similar to the biological SIS mesh, which was superior to the PG mesh. The PGI mesh provided preponderant mechanical supports over the SIS mesh and the native abdominal wall with similar compliance. Collectively, the newly developed mesh advances the intraperitoneal applicability of electrospun meshes by guiding a pro-remodeling response and offers a feasible functionalization approach upon immunomodulation.


Asunto(s)
Pared Abdominal , Ibuprofeno , Ratas , Animales , Ibuprofeno/farmacología , Pared Abdominal/cirugía , Gelatina/farmacología , Mallas Quirúrgicas , Prótesis e Implantes
20.
Materials (Basel) ; 17(14)2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39063798

RESUMEN

Flexible electrothermal heaters have attracted abundant attention in recent years due to their wide applications, but their preparation with high efficiency remains a challenge. Here in this work, a highly stable and bending-tolerant flexible heater was fabricated with graphite nanosheets and cellulose fibers through a scalable papermaking procedure. Its electrothermal property can be enhanced by a hot-pressing treatment and introduction of cationic polyacrylamide (CPAM) during the papermaking protocol. The flexible heater may quickly reach its maximum temperature of 239.8 °C in around 1 min at a voltage of 9 V. The power density was up to 375.3 °C cm2 w-1. It appeared to have a high tolerance for bending deformation with various curvatures, and the temperature remained stable even under 100 bending with frequency of around 0.17 Hz. Over 100 alternatively heating and cooling cycles, it worked stably as well. It was proved to be used as wearable heating equipment, soft heaters, and aircraft deicing devices, suggesting its great prospect in the field of heat management.

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