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1.
Small ; 20(5): e2305618, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37753872

RESUMO

Planar gliding along with anisotropic lattice strain of single-crystalline nickel-rich cathodes (SCNRC) at highly delithiated states will induce severe delamination cracking that seriously deteriorates LIBs' cyclability. To address these issues, a novel lattice-matched MgTiO3 (MTO) layer, which exhibits same lattice structure as Ni-rich cathodes, is rationally constructed on single-crystalline LiNi0.9 Co0.05 Mn0.05 O2 (SC90) for ultrastable mechanical integrity. Intensive in/ex situ characterizations combined with theoretical calculations and finite element analysis suggest that the uniform MTO coating layer prevents direct contact between SC90 and organic electrolytes and enables rapid Li-ion diffusion with depressed Li-deficiency, thereby stabilizing the interfacial structure and accommodating the mechanical stress of SC90. More importantly, a superstructure is simultaneously formed in SC90, which can effectively alleviate the anisotropic lattice changes and decrease cation mobility during successive high-voltage de/intercalation processes. Therefore, the as-acquired MTO-modified SC90 cathode displays desirable capacity retention and high-voltage stability. When paired with commercial graphite anodes, the pouch-type cells with the MTO-modified SC90 can deliver a high capacity of 175.2 mAh g-1 with 89.8% capacity retention after 500 cycles. This lattice-matching coating strategy demonstrate a highly effective pathway to maintain the structural and interfacial stability in electrode materials, which can be a pioneering breakthrough in commercialization of Ni-rich cathodes.

2.
Arch Microbiol ; 206(7): 307, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884653

RESUMO

Xylanase is the most important hydrolase in the xylan hydrolase system, the main function of which is ß-1,4-endo-xylanase, which randomly cleaves xylans to xylo-oligosaccharides and xylose. Xylanase has wide ranging of applications, but there remains little research on the cold-adapted enzymes required in some low-temperature industries. Glycoside hydrolase family 8 (GH8) xylanases have been reported to have cold-adapted enzyme activity. In this study, the xylanase gene dgeoxyn was excavated from Deinococcus geothermalis through sequence alignment. The recombinant xylanase DgeoXyn encodes 403 amino acids with a theoretical molecular weight of 45.39 kDa. Structural analysis showed that DgeoXyn has a (α/α)6-barrel fold structure typical of GH8 xylanase. At the same time, it has strict substrate specificity, is only active against xylan, and its hydrolysis products include xylobiose, xylotrinose, xytetranose, xylenanose, and a small amount of xylose. DgeoXyn is most active at 70 â„ƒ and pH 6.0. It is very stable at 10, 20, and 30 â„ƒ, retaining more than 80% of its maximum enzyme activity. The enzyme activity of DgeoXyn increased by 10% after the addition of Mn2+ and decreased by 80% after the addition of Cu2+. The Km and Vmax of dgeox were 42 mg/ml and 20,000 U/mg, respectively, at a temperature of 70 â„ƒ and pH of 6.0 using 10 mg/ml beechwood xylan as the substrate. This research on DgeoXyn will provide a theoretical basis for the development and application of low-temperature xylanase.


Assuntos
Deinococcus , Endo-1,4-beta-Xilanases , Estabilidade Enzimática , Xilanos , Deinococcus/enzimologia , Deinococcus/genética , Especificidade por Substrato , Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/metabolismo , Xilanos/metabolismo , Temperatura Baixa , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/química , Concentração de Íons de Hidrogênio , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Glicosídeo Hidrolases/química , Sequência de Aminoácidos , Hidrólise , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Alinhamento de Sequência , Clonagem Molecular , Cinética , Peso Molecular , Dissacarídeos
3.
Environ Res ; 261: 119700, 2024 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-39074770

RESUMO

The proliferation of nitrile mixtures has significantly exacerbated environmental pollution. This study employed metagenomic analysis to investigate the short-term effects of nitrile mixtures on soil microbial communities and their metabolic functions. It also examined the responses of indigenous microorganisms and their functional metabolic genes across various land use types to different nitrile stressors. The nitrile compound treatments in this study resulted in an increase in the abundance of Proteobacteria, Actinobacteria, and Firmicutes, while simultaneously reducing overall microbial diversity. The key genes involved in the denitrification process, namely, nirK, nosZ, and hao, were down-regulated, and NO3--N, NO2--N, and NH4+-N concentrations decreased by 7.7%-12.3%, 11.1%-21.3%, and 11.3%-30.9%, respectively. Notably, pond sludge samples exhibited a significant increase in the abundance of nitrogen fixation-related genes nifH, vnfK, vnfH, and vnfG following exposure to nitrile compounds. Furthermore, the fumarase gene fumD, which is responsible for catalyzing fumaric acid into malic acid in the tricarboxylic acid cycle, showed a substantial increase of 7.2-10.6-fold upon nitrile addition. Enzyme genes associated with the catechol pathway, including benB-xylY, dmpB, dmpC, dmpH, and mhpD, displayed increased abundance, whereas genes related to the benzoyl-coenzyme A pathway, such as bcrA, dch, had, oah, and gcdA, were notably reduced. In summary, complex nitrile compounds were found to significantly reduce the species diversity of soil microorganisms. Nitrile-tolerant microorganisms demonstrated the ability to degrade and adapt to nitrile pollutants by enhancing functional enzymes involved in the catechol pathway and fenugreek conversion pathway. This study offers insights into the specific responses of microorganisms to compound nitrile contamination, as well as valuable information for screening nitrile-degrading microorganisms and identifying nitrile metabolic enzymes.


Assuntos
Metagenoma , Nitrilas , Microbiologia do Solo , Poluentes do Solo , Nitrilas/toxicidade , Poluentes do Solo/toxicidade , Metagenoma/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Bactérias/genética
4.
J Magn Reson Imaging ; 57(5): 1594-1604, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36053805

RESUMO

BACKGROUND: Ocular adnexal lymphoma (OAL) and idiopathic orbital inflammation (IOI) are malignant and benign lesions for which radiotherapy and corticosteroids are indicated, but similar clinical manifestations make their differentiation difficult. PURPOSE: To develop and validate an MRI-based radiomics nomogram for individual diagnosis of OAL vs. IOI. STUDY TYPE: Retrospective. POPULATION: A total of 103 patients (46.6% female) with mean age of 56.4 ± 16.3 years having OAL (n = 58) or IOI (n = 45) were divided into an independent training (n = 82) and a testing dataset (n = 21). FIELD STRENGTH/SEQUENCE: A 3-T, precontrast T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), and postcontrast T1WI (T1 + C). ASSESSMENT: Radiomics features were extracted and selected from segmented tumors and peritumoral regions in MRI before-and-after filtering. These features, alone or combined with clinical characteristics, were used to construct a radiomics or joint signature to differentiate OAL from IOI, respectively. A joint nomogram was built to show the impact of the radiomics signature and clinical characteristics on individual risk of developing OAL. STATISTICAL TESTS: Area under the curve (AUC) and accuracy (ACC) were used for performance evaluation. Mann-Whitney U and Chi-square tests were used to analyze continuous and categorical variables. Decision curve analysis, kappa statistics, DeLong and Hosmer-Lemeshow tests were also conducted. P < 0.05 was considered statistically significant. RESULTS: The joint signature achieved an AUC of 0.833 (95% confidence interval [CI]: 0.806-0.870), slightly better than the radiomics signature with an AUC of 0.806 (95% CI: 0.767-0.838) (P = 0.778). The joint and radiomics signatures were comparable to experienced radiologists referencing to clinical characteristics (ACC = 0.810 vs. 0.796-0.806, P > 0.05) or not (AUC = 0.806 vs. 0.753-0.791, P > 0.05), respectively. The joint nomogram gained more net benefits than the radiomics nomogram, despite both showing good calibration and discriminatory efficiency (P > 0.05). DATA CONCLUSION: The developed radiomics-based analysis might help to improve the diagnostic performance and reveal the association between radiomics features and individual risk of developing OAL. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: 3.


Assuntos
Neoplasias Oculares , Linfoma , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Masculino , Nomogramas , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Inflamação
5.
Biotechnol Lett ; 45(9): 1199-1207, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37439931

RESUMO

OBJECTIVES: The lipase gene lipSR1 isolated from oil-contaminated soil exhibits high hydrolytic activity for short-chain fatty acid substrates. A single calcium ion is required to anchor the lid of LipSR1 in an open conformation by coordination with two aspartate residues and three other residues in the lid. The lid of LipSR1 is anchored by Ca2+, which is coordinated by side-chain carboxyl oxygens of Asp153 and Asp157, carbonyl oxygens of Thr118 and Ser144, and the side chain of Gln120. RESULTS: D157A, D153R, Q120A, S144A, and T118A mutants were produced by site-directed mutagenesis in this study. Analyses of hydrolytic activity and thermostability showed that the properties of D157A, D153R, Q120A, and S144A were almost lost, suggesting that Asp157, Asp153, Gln120, and Ser144 are important residues for LipSR1. However, the catalytic performance of T118A was clearly maintained. Moreover, the thermostability of mutant T118A was higher than that of wild-type LipSR1. CONCLUSIONS: These results indicated that mutation of threonine at position 118 improved the stability of the enzyme at high temperature.


Assuntos
Cálcio , Lipase , Lipase/química , Sítios de Ligação , Mutagênese Sítio-Dirigida , Mutação , Estabilidade Enzimática
6.
BMC Musculoskelet Disord ; 24(1): 625, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37532980

RESUMO

BACKGROUND: The risks associated with deep vein thrombosis (DVT) have gained significant recognition over time. A prevalent form of distal DVT is isolated calf muscular venous thrombosis (ICMVT). Despite its common clinical occurrence, data on ICMVT subsequent to tibial plateau fracture (TPF) surgery are scarce. This study aimed to examine the epidemiological characteristics and associated risk factors (RFs) of ICMVT following TPF surgery. METHODS: For this retrospective analysis, we included patients from our hospital, who underwent TPF surgery between March 2017 and March 2021. Patients' electronic medical records were reviewed, including admission details, fracture classification, surgical procedures, and laboratory biomarkers. The HSS (The American Hospital for Special Surgery) and Rasmussen scores were employed to evaluate the clinical effect. A Color Duplex Flow Imager (CDFI) was regularly used to detect pre- and postoperative venous thrombosis in the lower limbs. Finally, uni- and multivariate logistic regression analyses were used to identify independent RFs associated with ICMVT. RESULTS: Overall, 481 participants were recruited for analysis. Postoperative ICMVT occurred in 47 patients. All ICMVTs occurred on the affected side. Four of the 47 ICMVT patients exhibited sudden postoperative swelling in the affected limb. The HSS and Rasmussen scores in the non-ICMVT cohort (87.6 ± 8.2, 16.0 ± 1.7) were markedly different from the ICMVT cohort (84.8 ± 8.2, 15.5 ± 1.6) (p = 0.014, p = 0.031). This study finally identified five postoperative ICMVT-related RFs, which were age (> 55 years old) (OR 3.06; 95% CI 1.47-6.37; p = 0.003), gender (female) (OR 2.67; 95% CI 1.37-5.22; p = 0.004), surgical duration (> 114 min) (OR 3.14; 95% CI 1.44-6.85; p = 0.004), elevated white blood cell content (OR 2.85; 95% CI 1.47-5.51; p = 0.002), and hyponatremia (OR 2.31; 95% CI 1.04-5.12; p = 0.040). CONCLUSION: The epidemiological findings of this study may help predict ICMVT risk after surgery thus facilitating the development of individualized clinical assessments and targeted prevention programs.


Assuntos
Trombose , Fraturas da Tíbia , Fraturas do Planalto Tibial , Trombose Venosa , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Incidência , Perna (Membro) , Trombose Venosa/diagnóstico por imagem , Trombose Venosa/epidemiologia , Trombose Venosa/etiologia , Fatores de Risco , Fraturas da Tíbia/epidemiologia , Fraturas da Tíbia/cirurgia , Fraturas da Tíbia/complicações
7.
Int J Mol Sci ; 24(4)2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36834856

RESUMO

Deinococcus radiodurans is a microorganism that can adjust, survive or thrive in hostile conditions and has been described as "the strongest microorganism in the world". The underlying mechanism behind the exceptional resistance of this robust bacterium still remains unclear. Osmotic stress, caused by abiotic stresses such as desiccation, salt stress, high temperatures and freezing, is one of the main stresses suffered by microorganisms, and it is also the basic response pathway by which organisms cope with environmental stress. In this study, a unique trehalose synthesis-related gene, dogH (Deinococcus radiodurans orphan glycosyl hydrolase-like family 10), which encodes a novel glycoside hydrolase, was excavated using a multi-omics combination method. The content accumulation of trehalose and its precursors under hypertonic conditions was quantified by HPLC-MS. Ours results showed that the dogH gene was strongly induced by sorbitol and desiccation stress in D. radiodurans. DogH glycoside hydrolase hydrolyzes α-1,4-glycosidic bonds by releasing maltose from starch in the regulation of soluble sugars, thereby increasing the concentration of TreS (trehalose synthase) pathway precursors and trehalose biomass. The maltose and alginate content in D. radiodurans amounted to 48 µg mg protein-1 and 45 µg mg protein-1, respectively, which were 9 and 28 times higher than those in E. coli, respectively. The accumulation of greater intracellular concentrations of osmoprotectants may be the true reason for the higher osmotic stress tolerance of D. radiodurans.


Assuntos
Deinococcus , Maltose , Maltose/metabolismo , Deinococcus/genética , Glicosídeo Hidrolases/metabolismo , Amido/metabolismo , Escherichia coli/metabolismo , Trealose/metabolismo , Proteínas de Bactérias/metabolismo
8.
Int Wound J ; 20(9): 3690-3698, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37257885

RESUMO

Nutritional markers for adverse clinical outcomes following total joint arthroplasty (TJA) remain controversial. This study attempted to explore the validity of the albumin-to-fibrinogen ratio (AFR) in nutritional assessment and assess its predictive value for adverse postoperative outcomes in patients receiving TJA. 2137 patients who underwent primary TJA between January 2016 and June 2021 were screened. We performed receiver operating characteristic curves and area under the curve (AUC) to assess predictive value and establish optimal thresholds. Multivariate regression models were then used to assess potential associations between AFR and adverse postoperative outcomes. AFR might predict postoperative deep surgical site infections (AUC = 0.699, P = .023). The optimal threshold for wound complications, determined by the Youden index, was 12.96. Compared with patients with reduced AFR, patients with high AFR exhibited an enhanced risk of adverse postoperative outcomes (adjusted OR: 4.010-8.832, all P < .05). Using multivariate Cox regression analysis, we further confirmed a higher risk of adverse postoperative outcomes in patients with low AFR (adjusted HR: 3.733-7.335, all P < .05). Reduced preoperative AFR markedly enhanced adverse postoperative outcomes. Hence, AFR may serve as a potential biomarker for nutritional assessment, and may predict postoperative wound complications following primary TJA.


Assuntos
Albuminas , Fibrinogênio , Humanos , Fibrinogênio/análise , Estudos Retrospectivos , Artroplastia , Biomarcadores , Complicações Pós-Operatórias , Fatores de Risco
9.
HPB (Oxford) ; 25(1): 45-53, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36085261

RESUMO

BACKGROUND: Microvascular invasion (MVI) is an adverse factor for the prognosis of patients with hepatocellular carcinoma (HCC). We aimed to construct a preoperative prediction model for MVI, thereby providing a reference for clinicians in formulating treatment options for HCC. METHODS: A total of 360 patients with non-metastatic HCC were retrospectively enrolled. We used logistic regression analysis to screen out independent risk factors for MVI and further constructed a predictive model for MVI. The performance of the model was evaluated by receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA). RESULTS: Logistic regression analysis revealed that fibrinogen (>4 g/L) (OR: 6.529), alpha-fetoprotein (≥ 400 ng/mL) (OR: 2.676), cirrhosis (OR: 2.25), tumor size (OR: 1.239), and poor tumor border (OR: 3.126) were independent risk factors of MVI. The prediction model of MVI had C-index of 0.746 and 0.772 in the training and validation cohorts, respectively. The calibration curves showed good agreement between actual and predicted MVI risk. Finally, DCA reveals that this model has good clinical utility. CONCLUSION: The nomogram-based model we established can predict the preoperative MVI well and provides reference for surgeons to make clinical treatment decisions.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Invasividade Neoplásica/patologia , Prognóstico
10.
Environ Sci Technol ; 56(14): 10530-10542, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35772808

RESUMO

Terrestrial export of nitrogen is a critical Earth system process, but its global dynamics remain difficult to predict at a high spatiotemporal resolution. Here, we use deep learning (DL) to model daily riverine nitrogen export in response to hydrometeorological and anthropogenic drivers. Long short-term memory (LSTM) models for the daily concentration and flux of dissolved inorganic nitrogen (DIN) were built in a coastal watershed in southeastern China with a typical subtropical monsoon climate. The DL models exhibited excellent accuracy for both DIN concentration and flux, with Nash-Sutcliffe efficiency coefficients (NSEs) up to 0.67 and 0.92, respectively, a performance unlikely to be achieved by generic process-based models with comparable data quality. The flux model ensemble, without retraining, performed well (mean NSE = 0.32-0.84) in seven distinct watersheds in Asia, Europe, and North America, and retraining with multi-watershed data further improved the lowest NSE from 0.32 to 0.68. DL interpretation confirmed that interbasin consistency of riverine nitrogen export exists across different continents, which stems from the similarities in rainfall-runoff relationships. The multi-watershed flux model projects 0.60-12.4% increases in the nitrogen export to oceans from the studied watersheds under a 20% increase in fertilizer consumption, which rises to 6.7-20.1% with a 10% increase in runoff, indicating the synergistic effect of human activities and climate change. The DL-based method represents a successful case of explainable artificial intelligence in environmental science, providing a potential shortcut to a consistent understanding of the global daily-resolution dynamics of riverine nitrogen export under the currently limited data conditions.


Assuntos
Nitrogênio , Rios , Inteligência Artificial , China , Monitoramento Ambiental , Fertilizantes , Humanos , Nitrogênio/análise
11.
Eur Radiol ; 31(1): 24-33, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32789530

RESUMO

OBJECTIVES: To evaluate the effectiveness of bag-of-features (BOF)-based radiomics for differentiating ocular adnexal lymphoma (OAL) and idiopathic orbital inflammation (IOI) from contrast-enhanced MRI (CE-MRI). METHODS: Fifty-six patients with pathologically confirmed IOI (28 patients) and OAL (28 patients) were randomly divided into training (n = 42) and testing (n = 14) groups. One hundred sixty texture features extracted from the CE-MR image were encoded into the BOF representation with fewer features. The support vector machine (SVM) with a linear kernel was used as the classifier. Data augmented was performed by cropping orbital lesions in different directions to alleviate the over-fitting problem. Student's t test and the Holm-Bonferroni method were employed to compare the performance of different analysis methods. The chi-square test was used to compare the analysis with MRI and human radiological diagnosis. RESULTS: In the independent testing group, the differentiation by the BOF features with augmentation achieved an area under the curve (AUC) of 0.803 (95% CI: 0.725-0.880), which was significantly higher than that of the BOF features without augmentation and that of the texture features (p < 0.05). In addition, the same radiomic analysis with pre-contrast MRI obtained an AUC of 0.618 (95% CI: 0.560-0.677), which was significantly lower than that with CE-MRI. The diagnostic performance of the analysis with CE-MRI was significantly better than the radiology resident (p < 0.05) but had no significant difference with the experienced radiologist, even though there was less consistency between the radiomic analysis and the human visual diagnosis. CONCLUSIONS: The BOF-based radiomics may be helpful for the differentiation between OAL and IOI. KEY POINTS: • It is challenging to differentiate OAL from IOI due to the similar clinical and image features. • Radiomics has great potential for the noninvasive diagnosis of orbital diseases. • The BOF representation from patch to image may help the differentiation of OAL and IOI.


Assuntos
Linfoma , Imageamento por Ressonância Magnética , Área Sob a Curva , Humanos , Inflamação/diagnóstico por imagem , Linfoma/diagnóstico por imagem , Máquina de Vetores de Suporte
12.
Int J Mol Sci ; 22(9)2021 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-33923104

RESUMO

Most late embryogenesis abundant group 3 (G3LEA) proteins are highly hydrophilic and disordered, which can be transformed into ordered α-helices to play an important role in responding to diverse stresses in numerous organisms. Unlike most G3LEA proteins, DosH derived from Dinococcus radiodurans is a naturally ordered G3LEA protein, and previous studies have found that the N-terminal domain (position 1-103) of DosH protein is the key region for its folding into an ordered secondary structure. Synthetic biology provides the possibility for artificial assembling ordered G3LEA proteins or their analogues. In this report, we used the N-terminal domain of DosH protein as module A (named DS) and the hydrophilic domains (DrHD, BnHD, CeHD, and YlHD) of G3LEA protein from different sources as module B, and artificially assembled four non-natural hydrophilic proteins, named DS + DrHD, DS + BnHD, DS + CeHD, and DS + YlHD, respectively. Circular dichroism showed that the four hydrophile proteins were highly ordered proteins, in which the α-helix contents were DS + DrHD (56.1%), DS + BnHD (53.7%), DS + CeHD (49.1%), and DS + YLHD (64.6%), respectively. Phenotypic analysis showed that the survival rate of recombinant Escherichia coli containing ordered hydrophilic protein was more than 10% after 4 h treatment with 1.5 M NaCl, which was much higher than that of the control group. Meanwhile, in vivo enzyme activity results showed that they had higher activities of superoxide dismutase, catalase, lactate dehydrogenase and less malondialdehyde production. Based on these results, the N-terminal domain of DosH protein can be applied in synthetic biology due to the fact that it can change the order of hydrophilic domains, thus increasing stress resistance.


Assuntos
Escherichia coli/fisiologia , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Tolerância ao Sal/fisiologia , Antioxidantes/metabolismo , Catalase/metabolismo , Dicroísmo Circular , Simulação por Computador , Deinococcus/química , Interações Hidrofóbicas e Hidrofílicas , Malondialdeído/metabolismo , Viabilidade Microbiana , Microrganismos Geneticamente Modificados , Proteínas Recombinantes/genética , Superóxido Dismutase/metabolismo
13.
BMC Musculoskelet Disord ; 21(1): 21, 2020 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-31926554

RESUMO

BACKGROUND: The direct anterior approach for total hip arthroplasty (THA) has specific advantages, but injury to the tensor fasciae lata muscle (TFLM) remains a concern. This injury in part negates some of the advantages of the intermuscular approach, because injury of the muscle fibers of the TFLM can lead to less satisfactory clinical results. Thus, in this study, we propose an intraoperative method to protect the TFLM and demonstrate its feasibility. METHODS: Fifty-six patients undergoing THA by the direct anterior approach were divided randomly into two groups. In group A, the TFLM was protected by an autogenous tissue "pad" created from the anterior capsule of the joint which protect the TFLM from direct contact with the retractors. In group B, the operation was carried out with no protection of the TFLM except the attempt by the surgeons to consciously avoid injury of the TFLM. We evaluated magnitude of changes in the muscle cross-sectional area (MSCA) and fatty atrophy (FA) by magnetic resonance imaging. The differences in blood hemoglobin and serum levels of myoglobin, lactate dehydrogenase (LDH), and creatine phosphokinase (CPK) were compared at different time, postoperatively. The Harris hip score, postoperative drainage volume and visual analogue scores (VAS) were compared between the two groups. RESULTS: LDH, CPK and myoglobin in group B were significantly higher than group A at 8, 24, and 48 h after the surgery. (p < 0.05) Compared to the group A, the decrease of hemoglobin in group B displayed significantly at 24 and 48 h after surgery. (P < 0.05) The significantly increased MSCA and FA of TFLM were demonstrated in group B. The PDV and VAS in group B were significantly higher than group A. (P < 0.05) The Harris score in group A was significantly higher than group B (P < 0.05) one month after surgery, but there was no significant difference six months later. CONCLUSIONS: Using the anterior capsule of the hip joint as an autogenous, protective capsular tissue pad to limit the trauma to the TFLM during a direct anterior approach to THA is an effective method to protect the TFLM and improve the clinical effect. TRIAL REGISTRATION: ChiCTR: ChiCTR1900025173. Retrospectively registered August 15, 2019.


Assuntos
Artroplastia de Quadril/métodos , Fraturas do Colo Femoral/cirurgia , Idoso , Artroplastia de Quadril/estatística & dados numéricos , Fascia Lata , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tratamentos com Preservação do Órgão , Estudos Prospectivos
14.
Int J Mol Sci ; 20(22)2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31717497

RESUMO

Deinococcus radiodurans is best known for its extraordinary resistance to diverse environmental stress factors, such as ionizing radiation, ultraviolet (UV) irradiation, desiccation, oxidation, and high temperatures. The heat response of this bacterium is considered to be due to a classical, stress-induced regulatory system that is characterized by extensive transcriptional reprogramming. In this study, we investigated the key functional genes involved in heat stress that were expressed and accumulated in cells (R48) following heat treatment at 48 °C for 2 h. Considering that protein degradation is a time-consuming bioprocess, we predicted that to maintain cellular homeostasis, the expression of the key functional proteins would be significantly decreased in cells (RH) that had partly recovered from heat stress relative to their expression in cells (R30) grown under control conditions. Comparative transcriptomics identified 15 genes that were significantly downregulated in RH relative to R30, seven of which had previously been characterized to be heat shock proteins. Among these genes, three hypothetical genes (dr_0127, dr_1083, and dr_1325) are highly likely to be involved in response to heat stress. Survival analysis of mutant strains lacking DR_0127 (a DNA-binding protein), DR_1325 (an endopeptidase-like protein), and DR_1083 (a hypothetical protein) showed a reduction in heat tolerance compared to the wild-type strain. These results suggest that DR_0127, DR_1083, and DR_1325 might play roles in the heat stress response. Overall, the results of this study provide deeper insights into the transcriptional regulation of the heat response in D. radiodurans.


Assuntos
Deinococcus/genética , Regulação Bacteriana da Expressão Gênica , Resposta ao Choque Térmico , Transcriptoma , Proteínas de Bactérias/genética , Deinococcus/fisiologia , Extremófilos/genética , Extremófilos/fisiologia , Perfilação da Expressão Gênica , Análise de Sequência de RNA
15.
Int J Syst Evol Microbiol ; 64(Pt 6): 2108-2112, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24682704

RESUMO

A Gram-reaction-negative, rod-shaped, non-motile, red-pigmented, radiation-resistant, aerobic bacterium designated T-3(T) was isolated from a soil sample from the Qinghai-Tibet Plateau in Tibet, China, after exposure to 10 kGy gamma radiation. Phylogenetic analysis based on 16S rRNA sequences indicated that this isolate represented a novel member of the genus Hymenobacter. Sequence identities of the 16S rRNA gene of strain T-3(T) with the type strains of species of the genus Hymenobacter with validly published names range from 89% to 97%, and the most closely related species is Hymenobacter psychrotolerans Tibet-IIU11(T) (97%). The DNA-DNA relatedness between strain T-3(T) and H. psychrotolerans is 59.10%. The major fatty acids of strain T-3(T) were iso-C(15 : 0) (27.66%), summed feature 4 (iso-C(17 : 1)I and/or anteiso-C(17 : 1)B, 15.84%), anteiso-C(15 : 0) (14.08%) and summed feature 3 (C(16 : 1)ω7c and/or C(16 : 1)ω6c, 12.38%). The major menaquinone of strain T-3(T) was MK-7. Phosphatidylethanolamine (PE) was predominant in the polar lipid profile. The G+C content of the DNA of strain T-3(T) was 69.17 mol%. On the basis of the results of the polyphasic characterization presented in this study, it is concluded that strain T-3(T) represents a novel species of the genus Hymenobacter, for which the name Hymenobacter kanuolensis is proposed. The type strain is T-3(T) ( = ACCC 05760(T) = KCTC 32407(T)).


Assuntos
Cytophagaceae/classificação , Cytophagaceae/efeitos da radiação , Filogenia , Tolerância a Radiação , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Composição de Bases , China , Cytophagaceae/genética , Cytophagaceae/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Raios gama , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fosfatidiletanolaminas/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Vitamina K 2/análogos & derivados , Vitamina K 2/química
16.
Int J Syst Evol Microbiol ; 64(Pt 1): 248-253, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24052628

RESUMO

A novel, Gram-stain-negative, non-motile, non-spore-forming, short rod-shaped, aerobic bacterium designated H-12(T) was isolated from a mixed sandy soil sample collected from Xinjiang, China. Strain H-12(T) grew at 20-37 °C (optimum, 30 °C), pH 7.0-11.0 (optimum, pH 8.5) on TGY medium with 0-5 % NaCl (w/v). 16S rRNA gene sequence analysis indicated that strain H-12(T) shared sequence similarities with Sphingobacterium composti DSM 18850(T) (90.0 %). Strain H-12(T) showed a low level of DNA-DNA relatedness to Sphingobacterium composti DSM 18850(T) (45.5 %). The predominant isoprenoid quinone of strain H-12(T) was MK-7 and the major polar lipid was phosphatidylethanolamine. The predominant cellular fatty acids were C16:1ω7c and/or C16 : 1ω6c, iso-C15 : 0, iso-C17 : 0 3-OH, C16 : 0, C16 : 0 3-OH and iso-C15 : 0 3-OH. DNA G+C content of strain H-12(T) was 44.15 mol%. On the basis of phenotypic, genetic and phylogenetic data, strain H-12(T) is proposed to be a representative of a novel species of the genus Sphingobacterium, for which the name Sphingobacterium arenae sp. nov. is suggested and the type strain is H-12(T) ( = ACCC 05758(T) = KCTC 32294(T)).


Assuntos
Filogenia , Microbiologia do Solo , Sphingobacterium/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácidos Graxos/química , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fosfatidiletanolaminas/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Dióxido de Silício , Sphingobacterium/genética , Sphingobacterium/isolamento & purificação , Vitamina K 2/análogos & derivados , Vitamina K 2/química
17.
Sci Adv ; 10(13): eadl4005, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38536931

RESUMO

Estimating river flood risks under climate change is challenging, largely due to the interacting and combined influences of various flood-generating drivers. However, a more detailed quantitative analysis of such compounding effects and the implications of their interplay remains underexplored on a large scale. Here, we use explainable machine learning to disentangle compounding effects between drivers and quantify their importance for different flood magnitudes across thousands of catchments worldwide. Our findings demonstrate the ubiquity of compounding effects in many floods. Their importance often increases with flood magnitude, but the strength of this increase varies on the basis of catchment conditions. Traditional flood analysis might underestimate extreme flood hazards in catchments where the contribution of compounding effects strongly varies with flood magnitude. Overall, our study highlights the need to carefully incorporate compounding effects in flood risk assessment to improve estimates of extreme floods.

18.
Biomimetics (Basel) ; 9(5)2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38786480

RESUMO

The traditional golden jackal optimization algorithm (GJO) has slow convergence speed, insufficient accuracy, and weakened optimization ability in the process of finding the optimal solution. At the same time, it is easy to fall into local extremes and other limitations. In this paper, a novel golden jackal optimization algorithm (SCMGJO) combining sine-cosine and Cauchy mutation is proposed. On one hand, tent mapping reverse learning is introduced in population initialization, and sine and cosine strategies are introduced in the update of prey positions, which enhances the global exploration ability of the algorithm. On the other hand, the introduction of Cauchy mutation for perturbation and update of the optimal solution effectively improves the algorithm's ability to obtain the optimal solution. Through the optimization experiment of 23 benchmark test functions, the results show that the SCMGJO algorithm performs well in convergence speed and accuracy. In addition, the stretching/compression spring design problem, three-bar truss design problem, and unmanned aerial vehicle path planning problem are introduced for verification. The experimental results prove that the SCMGJO algorithm has superior performance compared with other intelligent optimization algorithms and verify its application ability in engineering applications.

19.
Pest Manag Sci ; 80(3): 1348-1360, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37915287

RESUMO

BACKGROUND: During unmanned aerial vehicles (UAVs) spraying, downwash and crosswind generate back pressure in comprehensive, which changes in spatial atomization characteristics of spraying droplets. However, the process of such atomization characteristics needs to be clarified. This study focuses on the effect of rotor speed and crosswind speed on spatial atomization characteristics. The computational fluid dynamics (CFD) models of the distributions of airflow, back pressure and atomization characteristics were established, and verification was conducted by developing a validation platform. RESULTS: The CFD results indicated that small droplets of 65-130 µm atomized by negative pressure would be coalesced near the nozzle, while large droplets of 390-520 µm atomized by positive pressure would be aggregated further away. Crosswind caused atomization stratification with droplet sizes of approximately 90 µm, 320 µm and 390 µm. When crosswind speed increased from 3 m/s to 6 m/s, the spraying drifted from 0.5 m to 1 m. When rotor speed increased from 2000 RPM to 3000 RPM, droplet distribution was expanded and droplet particle size was more uniform. Verification results demonstrated that the spraying distribution and the droplet size variation were consistent with the CFD. CONCLUSIONS: Spatial atomization characteristics were highly correlated with airflow and back pressure. Moreover, as crosswind generated droplet drift and atomization stratification and downwash could improve the uniformity of droplet distribution, spraying performance was superior by enhancing downwash to restrain the adverse effect of crosswind in real applications. © 2023 Society of Chemical Industry.


Assuntos
Hidrodinâmica , Tamanho da Partícula
20.
ChemSusChem ; : e202401391, 2024 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-39305467

RESUMO

Perfluorooctanoic acid (PFOA) is currently one of the most important chemicals posing environmental risks, and there is an urgent need to find methods to efficiently remove PFOA from environmental media. Here, two decaamino-pillar[5]arene-based fluorine-rich polymer networks, called FA2P-P and FA6P-P, were constructed using a convenient method. FA6P-P had an excellent ability to take up PFOA, and had a capacity of 1423 (mg PFOA) (g FA6P-P) -1, which is the second highest adsorption capacity reported for any PFOA sorbent. FA6P-P removed >99% of the PFOA from a solution and decreased the PFOA concentration from 1000 µg L-1 in 5 min at an exceedingly low adsorbent loading of 0.7 mg L-1, giving a final PFOA concentration <4 ng L-1, which is lower than the most recent enforceable maximum concentration set by the United States Environmental Protection Agency. A high rate constant (kobs) of 55.8 g mg-1 h-1 was observed. Pillar[5]arene gives the material hydrophobic properties and also amino sites and hydrophobic chains, which are synergistic PFOA binding sites. The polymer was very stable and readily regenerated. The results indicated that pillar[5]arene-based porous organic polymer sorbents are excellent candidates for capturing PFOA.

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