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1.
Anal Chem ; 96(14): 5664-5668, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38530953

RESUMO

Per- and polyfluoroalkyl substances (PFAS) have caused widespread environmental concern in recent years. Among them, the levels of perfluoroalkane sulfonyl fluorides (PFASFs) in the environment have rarely been reported due to the lack of sensitive analytical methods. Herein, a novel liquid chromatography-microwave plasma torch ionization-mass spectrometry (LC-MPTI-MS) technique was designed for the direct analysis of PFASFs in the environment. The collaborative action of reactive oxygen species (such as hydroxyl radicals) and the elevated temperature within the ambient MPTI environment results in the replacement of the fluorine atom in sulfonyl fluoride by oxygen, leading to the detection of perfluoroalkanesulfonic acid (PFSA) ions by MS. Concurrently, LC was employed to separate other PFSAs that are present in the environment. Three PFASFs exhibited good linearity within the range of 1-500 µg/L with R2 > 0.994. The limit of detections (LODs) and the limit of quantifications (LOQs) were measured at 39.32-87.87 and 131.07-292.90 ng/L, respectively. The method was utilized for the direct detection of spiked perfluorooctane sulfonyl fluoride (PFOSF) in wastewater with recoveries of 77.16 to 124.81%. Our approach circumvents the laborious process of chemical derivatization and is anticipated to serve as a robust tool for determining the levels and behaviors of PFASFs in the environment.

2.
J Sep Sci ; 46(23): e2300415, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37802974

RESUMO

Sucrose esters (SEs) are crucial tobacco smoke flavor precursors and play a significant role in tobacco's functionality. Due to their structural complexity, the separation and analysis of SEs in tobacco remain a major challenge, and massive structures of SEs have not yet been fully identified. In this study, the fractions enriched in SEs were obtained from oriental and flue-cured tobacco through a series of pretreatments, and two types of SEs (Types I and II) were distinguished by liquid chromatography-tandem mass spectrometry (LC-MSn ) analysis, with Type II SEs newly characterized in tobacco. Five groups of main SEs were further purified using preparative high-performance LC (HPLC) coupled to an evaporative light scattering detector, and their structures were characterized by nuclear magnetic resonance spectrometry techniques including 1 H, 13 C, correlation spectroscopy, heteronuclear single quantum correlation, and heteronuclear multiple bond correlation. By combining LC-MSn and nuclear magnetic resonance spectrometry, the structures of eight SE isomers were finally proposed, of which four were newly identified. These findings further enhance the understanding of the structural diversity of SEs in tobacco, serving as a valuable reference for future research on the elucidation, synthesis, and metabolism of SEs.


Assuntos
Ésteres , Sacarose , Espectrometria de Massas , Cromatografia Líquida , Isomerismo , Cromatografia Líquida de Alta Pressão/métodos
3.
Chirality ; 32(8): 1080-1090, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32383525

RESUMO

Novel chiral selectors based on 3,5-dimethyl phenylcarbamoylated ß-cyclodextrin connecting quinine (QN) or quinidine (QD) moiety were synthesized and immobilized on silica gel. Their chromatographic performances were investigated by comparing to the 3,5-dimethyl phenylcarbamoylated ß-cyclodextrin (ß-CD) chiral stationary phase (CSP) and 9-O-(tert-butylcarbamoyl)-QN-based CSP (QN-AX). Fmoc-protected amino acids, chiral drug cloprostenol (which has been successfully employed in veterinary medicine), and neutral chiral analytes were evaluated on CSPs, and the results showed that the novel CSPs characterized as both enantioseparation capabilities of CD-based CSP and QN/QD-based CSPs have broader application range than ß-CD-based CSP or QN/QD-based CSPs. It was found that QN/QD moieties play a dominant role in the overall enantioseparation process of Fmoc-amino acids accompanied by the synergistic effect of ß-CD moiety, which lead to the different enantioseparation of ß-CD-QN-based CSP and ß-CD-QD-based CSP. Furthermore, new CSPs retain extraordinary enantioseparation of cyclodextrin-based CSP for some neutral analytes on normal phase and even exhibit better enantioseparation than the corresponding ß-CD-based CSP for certain samples.

4.
J Sep Sci ; 43(12): 2338-2348, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32216077

RESUMO

In this study, a series of chiral stationary phases based on N-[(4-methylphenyl)sulfonyl]-l-leucine amide, whose enantiorecognition property has never been studied, were synthesized. Their enantioseparation abilities were chromatographically evaluated by 67 enantiomers. The chiral stationary phase derived from N-[(4-methylphenyl)sulfonyl]-l-leucine showed much better enantioselectivities than that based on N-(4-methylbenzoyl)-l-leucine amide. The construction of C2 symmetric chiral structure greatly improved the enantiorecognition performance of the stationary phase. The C2 symmetric chiral stationary phase exhibited superior enantioresolutions to other chiral stationary phases for most of the chiral analytes, especially for the chiral analytes with C2 symmetric structures. By comparing the enantioseparations of the enantiomers with similar structures, the importance of hydrogen bond interaction, π-π interaction, and steric hindrance on enantiorecognition was elucidated. The enantiorecognition mechanism of trans-N,N'-(1,2-diphenyl-1,2-ethanediyl)bis-acetamide, which had an excellent separation factor on the C2 symmetric chiral stationary phase, was investigated by 1 H-NMR spectroscopy and 2D 1 H-1 H nuclear overhauser enhancement spectroscopy.


Assuntos
Leucina/química , Leucina/análogos & derivados , Leucina/síntese química , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Estereoisomerismo
5.
Clin Rehabil ; 34(12): 1497-1505, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32602373

RESUMO

OBJECTIVE: To investigate the effect of small needle-knife therapy in people with painful knee osteoarthritis. DESIGN: Pilot randomised, controlled trial. SETTING: Rehabilitation hospital. SUBJECTS: In-patients with osteo-arthritis of the knee. INTERVENTIONS: Either 1 to 3 small needle-knife treatments over seven days or oral Celecoxib. All patients stayed in hospital three weeks, receiving the same mobility-focused rehabilitation. MEASURES: Oxford Knee Score (OKS), gait speed and kinematics were recorded at baseline, at three weeks (discharge) and at three-months (OKS only). Withdrawal from the study, and adverse events associated with the small needle knife therapy were recorded. RESULTS: 83 patients were randomized: 44 into the control group, of whom 10 were lost by three weeks and 12 at 3 months; 39 into the experimental group of whom eight were lost at three weeks and three months. The mean (SE) OKS scores at baseline were Control 35.86 (1.05), Exp 38.38 (0.99); at three weeks 26.64 (0.97) and 21.94 (1.23); and at three months 25.83 (0.91) and 20.48 (1.14) The mean (SE) gait speed at baseline was 1.07 (0.03) m/sec (Control) and 0.98 (0.03), and at three weeks was 1.14 (0.03) and 1.12 (0.03) (P < 0.05). Linear mixed model statistical analysis showed that the improvements in the experimental group were statistically significant for total OKS score at discharge and three months. CONCLUSIONS: Small needle-knife therapy added to standard therapy for patients with knee osteoarthritis, was acceptable, safe and reduced pain and improved global function on the Oxford Knee Score. Further research is warranted.


Assuntos
Terapia por Acupuntura , Microcirurgia , Osteoartrite do Joelho/terapia , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Projetos Piloto , Velocidade de Caminhada
6.
Chirality ; 31(10): 855-864, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31423667

RESUMO

As an important intermediate of prostaglandins and entecavir, optically pure Corey lactone diol (CLD) has great value in the pharmaceutical industry. In this work, the enantioseparation of (±)-CLD was evaluated using high-performance liquid (HPLC) and supercritical fluid chromatography (SFC). In HPLC, the separations of CLD enantiomers on polysaccharide-based chiral stationary phases with both normal phase and polar organic phase were screened. And the conditions for the enantioseparation were optimized in HPLC and SFC, including the selection of mobile phase, temperature, back-pressure, and other conditions. More important, it was found that the chiral resolutions were greatly enhanced by the increase of the coating amount of ADMPC (amylose tris-(3,5-dimethylphenylcarbamate)) under both HPLC and SFC conditions, which can lead to the increase of the productivity and the decrease of the solvent consumption. The preparations of optically pure CLD were evaluated on a semi-preparative (2 × 25 cm) column packed with 30% ADMPC-coated CSP under HPLC and SFC conditions. Preparative performances in terms of kkd are 1.536 kg racemate/kg CSP/day and 1.248 kg racemate/kg CSP/day in HPLC and SFC, respectively.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia com Fluido Supercrítico/métodos , Lactonas/química , Lactonas/isolamento & purificação , Amilose/análogos & derivados , Amilose/química , Fenilcarbamatos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Estereoisomerismo , Temperatura
7.
J Nanosci Nanotechnol ; 18(12): 7983-8002, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30189916

RESUMO

Nanotechnology is an emerging science in food production and processing sector, yet the role of nanotechnology in food safety has not been comprehensively reviewed. This study reviewed the types, sources and mode of actions of the nanoparticles used in the food systems. Additionally, the effect of nanoparticles on animal health and safety of the products of animal origin was evaluated. Moreover, retention of nutritionally important nanoparticle minerals in the animal systems and foods of animal origins was analyzed. Furthermore, food safety was critically evaluated in terms of antioxidative ability, antibacterial properties, and toxicological studies. Finally, the scope of nanoparticle-based functional foods and shelf-life enhancement using active packaging was discussed. The article concluded that although significant research has been done on the use of nanoparticles in food systems, yet commercialization of nanoparticle-based foods needs further investigation.


Assuntos
Inocuidade dos Alimentos , Nanopartículas , Nanotecnologia , Animais , Embalagem de Alimentos , Nanopartículas/toxicidade
8.
ScientificWorldJournal ; 2014: 451919, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25097877

RESUMO

A new multicylinder microchamber reactor is designed on autothermal reforming of methane for hydrogen production, and its performance and thermal behavior, that is, based on the reaction mechanism, is numerically investigated by varying the cylinder radius, cylinder spacing, and cylinder layout. The results show that larger cylinder radius can promote reforming reaction; the mass fraction of methane decreased from 26% to 21% with cylinder radius from 0.25 mm to 0.75 mm; compact cylinder spacing corresponds to more catalytic surface and the time to steady state is decreased from 40 s to 20 s; alteration of staggered and aligned cylinder layout at constant inlet flow rates does not result in significant difference in reactor performance and it can be neglected. The results provide an indication and optimize performance of reactor; it achieves higher conversion compared with other reforming reactors.


Assuntos
Hidrogênio/química , Metano/química , Microquímica/instrumentação , Catálise , Microquímica/métodos
9.
Nat Prod Res ; : 1-9, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38770927

RESUMO

The Marsdenia tenacissima, has been used as traditional Chinese medicine for six hundred years. Our chemical investigation on the stem of Marsdenia tenacissima led to the isolation of one new pregnane glycoside, namely, marsdeoside J (compound 1) and twelve known compounds. The structure of the new compound was elucidated by spectroscopic analysis including 1D and 2D NMR, HRESIMS, IR, and UV. The absolute configurations of the sugar moiety were identified by comparing the specific optical rotations and Rf values with those of the commercially available standards and the data reported in the literature. Compound 1 showed cytotoxicities against five human cancer cell lines, with IC50 values ranging from 6.5 to 18.1 µM and certain inhibitory activities on NO production.

10.
Artigo em Inglês | MEDLINE | ID: mdl-38770602

RESUMO

Objective: To evaluate the efficacy and safety of ultrasound-guided acupotomy (UgA) for the treatment of thoracodorsal myofascial pain syndrome (TDMPS) and monitor its mid-term efficacy at 3 months after treatment. Methods: A 3-week, evaluator-blinded randomized clinical trial was conducted among 100 patients with TDMPS (visual analogue scale [VAS] score > 3) in the outpatient clinic of the Department of Orthopaedics of the Second Affiliated Hospital of Anhui University of Traditional Chinese Medicine, with a 3-month follow-up starting after completion of treatment. These patients were randomly assigned to receive UgA (n = 50) or oral celecoxib (n = 50). Recruitment was conducted between January 2021 and July 2022. The primary outcome was the VAS score, and the secondary outcomes included the Oswestry Disability Index (ODI), Pain Anxiety Symptoms Scale (PASS), and TNF-α and IL-1ß levels. Outcome data were collected at baseline, week 3 (post-treatment) and week 15 (follow-up). Results: Compared with that in the celecoxib group, the pain in the UgA group was alleviated more strongly, with an adjusted mean group difference of -0.69 (95% CI,-1.07 to -0.31 after multiple imputation) at week 3 and -1.96 (95% CI,-2.33 to -1.59 after multiple imputation) at week 15 (p < 0.001 for overall group × time interaction). Both groups exhibited improvements in the ODI and PASS scores at weeks 3 and 15, but these improvements were significantly greater in the UgA group (p < 0.05). At week 3, the TNF-α and IL-1 levels were significantly lower in both groups, but celecoxib was more effective (p < 0.05). Results from analyses with multilevel multiple imputation for missingness were similar. Conclusion: UgA led to greater and safer alleviation of pain, dysfunction, and pain anxiety in patients treated with TDMPS than did celecoxib and had a durable 3-month efficacy but was inferior to celecoxib in reducing the level of inflammatory factors. These findings may prompt clinicians to recommend UgA as an alternative and supplementary therapy for pain management in patients with TDMPS.

11.
Materials (Basel) ; 17(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38793417

RESUMO

The fatigue behavior of a high-strength bearing steel tempered under three different temperatures was investigated with ultrasonic frequency and conventional frequency loading. Three kinds of specimens with various yield strengths exhibited obvious higher fatigue strengths under ultrasonic frequency loading. Then, a 2D crystal plasticity finite element method was adopted to simulate the local stress distribution under different applied loads and loading frequencies. Simulations showed that the maximum residual local stress was much smaller under ultrasonic frequency loading in contrast to that under conventional frequency at the same applied load. It was also revealed that the maximum local stress increases with the applied load under both loading frequencies. The accumulated plastic strain was adopted as a fatigue indicator parameter to characterize the frequency effect, which was several orders smaller than that obtained under conventional loading frequencies when the applied load was fixed. The increment of accumulated plastic strain and the load stress amplitude exhibited a linear relationship in the double logarithmic coordinate system, and an improved fatigue life prediction model was established.

12.
Front Med (Lausanne) ; 11: 1400757, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38863886

RESUMO

Background: Some cohort studies have explored the effects and safety of polymyxin B (PMB) in comparison to other antibiotics for the treatment of nosocomial infections, yielding inconsistent results. This systematic review aims to explore the effectiveness and safety of PMB and compared it with other antibiotics. Methods: A systematic literature search was conducted in PubMed, Embase, the Cochrane Library, and Web of Science, searching specific terms to identify quantitative cohort studies or RCTs that compared the effects of PMB with other antibiotics in terms of their efficacy and safety. The Newcastle-Ottawa Scale (NOS) was conducted to evaluate the risk of bias of observational studies. Odds ratios with 95% confidence intervals were used for outcome assessment. We evaluated heterogeneity using the I 2 test. Results: A total of 22 observational trials were included in the analysis. The PMB group had a higher mortality rate compared to the control group (odds ratio: 1.84, 95% CI: 1.36-2.50, p<0.00001, I 2 = 73%). while, the ceftazidime-avibactam group demonstrated a distinct advantage with lower mortality rates, despite still exhibiting high heterogeneity (odds ratio 2.73, 95% confidence interval 1.59-4.69; p = 0.0003; I 2 = 53%). Additionally, the PMB group had a lower nephrotoxicity rate compared to the colistin group but exhibited high heterogeneity in the results (odds ratio 0.58, 95% CI 0.36-0.93; p = 0.02; I 2 = 73%). Conclusion: In patients with nosocomial infections, PMB is not superior to other antibiotics in terms of mortality, specifically when compared to ceftazidime-avibactam. However, PMB demonstrated an advantage in terms of nephrotoxicity compared to colistin.

13.
IEEE Trans Pattern Anal Mach Intell ; 45(3): 3311-3328, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35763471

RESUMO

Generating photo-realistic images from labels (e.g., semantic labels or sketch labels) is much more challenging than the general image-to-image translation task, mainly due to the large differences between extremely sparse labels and detail rich images. We propose a general framework Lab2Pix to tackle this issue from two aspects: 1) how to extract useful information from the input; and 2) how to efficiently bridge the gap between the labels and images. Specifically, we propose a Double-Guided Normalization (DG-Norm) to use the input label for semantically guiding activations in normalization layers, and use global features with large receptive fields for differentiating the activations within the same semantic region. To efficiently generate the images, we further propose Label Guided Spatial Co-Attention (LSCA) to encourage the learning of incremental visual information using limited model parameters while storing the well-synthesized part in lower-level features. Accordingly, Hierarchical Perceptual Discriminators with Foreground Enhancement Masks are proposed to toughly work against the generator thus encouraging realistic image generation and a sharp enhancement loss is further introduced for high-quality sharp image generation. We instantiate our Lab2Pix for the task of label-to-image in both unpaired (Lab2Pix-V1) and paired settings (Lab2Pix-V2). Extensive experiments conducted on various datasets demonstrate that our method significantly outperforms state-of-the-art methods quantitatively and qualitatively in both settings.

14.
Front Endocrinol (Lausanne) ; 14: 1249070, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38161971

RESUMO

Background: Relationships of the polymorphisms in fat mass and obesity-associated gene (FTO) and peroxisome proliferator-activated receptor delta gene (PPARD) with metabolic-related diseases remain to be clarified. Methods: One thousand three hundred and eighty-one subjects were enrolled. Metabolic-related diseases including obesity, dyslipidemia, hyperhomocysteinemia, hyperuricemia, hypertension, type 2 diabetes mellitus (T2DM) and coronary artery disease (CAD) were defined based on diagnostic criteria. FTO rs9939609 and rs17817449, and PPARD rs2016520 and rs2267668 polymorphisms were genotyped by using polymerase chain reaction-restricted fragment length polymorphism method. Results: Patients with T2DM or dyslipidemia had a higher frequency of AA, AT or AA + AT genotypes as well as A allele of FTO rs9939609 polymorphism than those free of T2DM or dyslipidemia (P ≤ 0.04 for all). Patients with T2DM or dyslipidemia had a higher frequency of GG, GT or GG + GT genotypes as well as G allele of FTO rs17817449 polymorphism than those free of T2DM or dyslipidemia (P ≤ 0.03 for all). Multivariate logistic regression analyses showed that FTO rs9939609 and rs17817449 polymorphisms were independently associated with T2DM as well as dyslipidemia after adjustment for age, sex, smoking and other metabolic diseases. FTO rs9939609 and rs17817449 polymorphisms were not associated with obesity, hyperhomocysteinemia, hyperuricemia, hypertension and CAD. Obese or T2DM carriers of the AA or AT genotype of the FTO rs9939609 polymorphism had a higher prevalence of dyslipidemia compared to non-obese or non-T2DM carriers of the AA or AT genotype (P = 0.03 for both). Among the carriers of GG or GT genotype of the FTO rs17817449 polymorphism, the prevalence of dyslipidemia in obese patients was higher than that in non-obese subjects (P < 0.01). PPARD rs2016520 and rs2267668 polymorphisms were not correlated with any of the metabolic-related diseases in the study population. Conclusion: Minor alleles of FTO rs9939609 and rs17817449 polymorphisms confer a higher risk of T2DM and dyslipidemia, and the risk is further increased among obese individuals. PPARD rs2016520 and rs2267668 polymorphisms are not associated with metabolic-related diseases.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato , Doença da Artéria Coronariana , Diabetes Mellitus Tipo 2 , Dislipidemias , Humanos , Alelos , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , China/epidemiologia , Doença da Artéria Coronariana/epidemiologia , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/complicações , Diabetes Mellitus Tipo 2/complicações , Dislipidemias/genética , Dislipidemias/complicações , Hiper-Homocisteinemia/complicações , Hiper-Homocisteinemia/genética , Hipertensão/epidemiologia , Hipertensão/genética , Hipertensão/complicações , Hiperuricemia/complicações , Obesidade/complicações , Obesidade/genética , Obesidade/epidemiologia , Polimorfismo de Nucleotídeo Único , População do Leste Asiático
15.
Prev Med Rep ; 34: 102276, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37309358

RESUMO

The purpose of the systematic review was to evaluate the efficacy and safety of interleukin-6 receptor (IL-6) antagonists (tocilizumab, sarilumab) in adult patients with severe or critical COVID-19. A systematic review of the literature was conducted in Medline, Cochrane and Embase databases, and World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) and ClinicalTrials.gov from the inception dates to10 January 2023. Randomized clinical trials comparing IL-6 receptor antagonists (tocilizumab, sarilumab) with a placebo or usual care treatment for adult patients with severe or critical COVID-19 were identified. Two independent reviewers performed the assessment and selection of eligible studies, assessed study quality and extracted data. Relative risk (RR), mean difference (MD), and 95% confidence interval (CI) with random-effects models was performed in meta-analysis. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology was used to assess the quality of the evidence. The search retrieved a total of 11 RCTs involving 5028 participants were eligible for meta-analysis. Our findings suggest that as the new drug used in adult patients with severe or critical COVID-19, IL-6 antagonists (tocilizumab, sarilumab) may reduce the length of ICU stay and hospital stay. However, they did not significantly increase the risks of serious adverse events and did not reduce all-cause mortality (28-day, 14-day, and 7-day).

16.
Arthroplasty ; 5(1): 65, 2023 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-38042843

RESUMO

PURPOSE: Patellofemoral arthroplasty (PFA) was shown to be a potentially effective surgical technique for isolated patellofemoral osteoarthritis but varying reports on PFA-related implant failure and complications have rendered the procedure controversial. This study aimed to identify impactful publications, research interests/efforts, and collaborative networks in the field of PFA research. METHODS: The study used the Web of Science Core Collection (WOSCC) database, Medline, Springer, BIOSIS Citation Index, and PubMed to retrieve relevant publications on PFA research published between 1950-2022. Statistical tests in R software were used for analysis while VOSviewer, Bibliometrix, and CiteSpace were employed for data visualization. RESULTS: Two hundred forty-one articles were analyzed with the number of published papers increasing over time. Knee was the most frequent journal and Clinical Orthopaedics and Related Research was the most cited journal. Clinical outcomes, such as prosthesis survival, revision, and complications, were researched most frequently as demonstrated by keyword analysis. The United States was the top contributor to cooperative networks, followed by the United Kingdom while Technical University Munich formed close ties among authors. CONCLUSION: Publications on PFA research have witnessed a notable surge. They primarily came from a limited number of centers and were characterized by low-level evidence. The majority of studies primarily focused on the clinical outcomes of PFA, while revision of PFA and patient satisfaction have emerged as new research areas.

17.
J Mater Chem B ; 11(46): 11150-11163, 2023 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-37971358

RESUMO

This paper investigates physically crosslinked organo-hydrogels for total hip replacement surgery. Current materials in artificial joints have limitations in mechanical performance and biocompatibility. To overcome these issues, a new approach based on hydrogen bonds between polyvinyl alcohol, poly(2-hydroxyethyl methacrylate), and glycerin is proposed to develop bioactive organo-hydrogels with improved mechanical properties and biocompatibility. This study analyzes local pathological characteristics, systemic toxicity, and mechanical properties of the gels. The results show that the gels possess excellent biocompatibility and mechanical strength, suggesting their potential as an alternative material for total hip replacement surgery. These findings contribute to improving patient outcomes in joint replacement procedures.


Assuntos
Artroplastia de Substituição , Hidrogéis , Humanos , Hidrogéis/química , Fricção , Álcool de Polivinil/química
18.
J Robot Surg ; 17(6): 2973-2985, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37882976

RESUMO

Robotic-assisted surgical systems hold promise in enhancing total knee arthroplasty (TKA) outcomes and patients' quality of life. This study aims to comprehensively analyze the literature on robot-assisted total knee arthroplasty (r-TKA), providing insights into its current development, clinical application, and research trends. A systematic search was conducted in the Web of Science Core Collection (WOSCC) to identify relevant articles. Data were collected from the top 100 highly cited articles. Article evidence levels were assessed following established guidelines. Statistical analyses and visualizations were performed to reveal publication trends, citations, research hotspots, and collaborative networks. The analysis covered 100 highly cited articles meeting the research criteria, with a focus on the last five years. The United States emerged as a major contributor, with most publications and citations in the Journal of Knee Surgery and Knee Surgery Sports Traumatology Arthroscopy. Research priorities revolved around clinical outcomes, accuracy, and alignment of r-TKA. Notably, higher evidence levels correlated with more citations, indicating greater attention. Interest in and research on r-TKA is steadily increasing, with a few countries at the forefront of these endeavors. While numerous studies have already reported short- to medium-term follow-up results, it is crucial to conduct longer-term investigations to gain a more comprehensive understanding of the clinical benefits that r-TKA offers compared to conventional techniques. Through ongoing research and a greater embrace of robotic technology, we can continue to improve the quality of life for patients undergoing knee arthroplasty.


Assuntos
Artroplastia do Joelho , Procedimentos Cirúrgicos Robóticos , Humanos , Artroplastia do Joelho/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Qualidade de Vida , Articulação do Joelho/cirurgia , Bibliometria
19.
Medicine (Baltimore) ; 101(30): e29447, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35905254

RESUMO

RATIONALE: The treatment of severe acute respiratory distress syndrome caused by accidental inhalation of nitric acid fumes is challenging. Few successful cases have been reported in literature. Owing to the development of extracorporeal life support, extracorporeal membrane oxygenation (ECMO) may play an important role in treatment. PATIENT CONCERNS: A 40-year-old man was accidentally exposed to nitric acid fumes for 10 minutes in a factory. Mild throat irritation and dyspnea occurred 3.5 hours after exposure. Severe dyspnea recurred approximately two hours later. Chest computed tomography revealed bilateral interstitial edema. Tracheal intubation and mechanical ventilation were provided when the non-invasive ventilator failed to support the patient. However, his vital signs, respiratory function, and circulation were aggravated. DIAGNOSIS: Aspiration pneumonia (inhalation of nitric acid fumes), acute respiratory distress syndrome, and hypertension. INTERVENTIONS: Veno-venous ECMO (VV-ECMO) was started 6 hours after exposure at the intensive care unit. During VV-ECMO, hypoxia improved. However, chest radiography revealed aggravated pulmonary edema. Prone positioning under ultrasound monitoring and high-dose methylprednisolone were administered on the first day. Nebulization and fiberoptic bronchoscopy for airway management were performed on the second day after the exposure. Pulmonary secretions were significantly reduced 48 hours later. OUTCOMES: The patient was weaned off V-V ECMO after 6 days, achieved the standard of extubation after 9 days, and was discharged without serious pulmonary or infectious complications after 12 days of hospitalization. Three weeks after discharge, the patient's lung function showed a slight decline in the diffusion function. Two months after discharge, the patient's lung function returned to normal. LESSON: Early ECMO combined with prone positioning and visualized management through ultrasonography can better improve the prognoses of patients and promote lung function recovery.


Assuntos
Oxigenação por Membrana Extracorpórea , Síndrome do Desconforto Respiratório , Adulto , Dispneia , Oxigenação por Membrana Extracorpórea/métodos , Humanos , Masculino , Ácido Nítrico , Respiração Artificial , Síndrome do Desconforto Respiratório/diagnóstico por imagem , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/terapia
20.
Materials (Basel) ; 15(2)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35057135

RESUMO

High energy density materials (HEDM) are the subject of an extensive research effort in relation to the use of these compounds as components of rocket propellants, powders, and formulations of high-performance explosives. Hexanitrohexaazaisowurtzitane (HNIW, i.e., CL-20) has received much attention in these research fields for its specific impulse, burning rate, ballistics, and detonation velocity. In this paper, the development and performances of the explosives from the first to the fourth generation are briefly summarized, and the synthesis status of the fourth-generation explosive, HNIW, is reviewed. The key issues that restrict the development of industrial amplification synthesis of HNIW are analyzed, and the potential directions of development are proposed. It is pointed out that to synthesize new and efficient catalysts is the key to making the cost-effective manufacturing of CL-20 a reality.

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