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1.
Materials (Basel) ; 17(3)2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38591537

RESUMO

The material undergoes high temperature and high strain rate deformation process during the cutting process, which may induce the dynamic recrystallization behavior and result in the evolution of dynamic mechanical properties of the material to be machined. In this paper, the modified Johnson-Cook (J-C) model for nickel-based powder metallurgy superalloy considering dynamic recrystallization behavior in high strain rate and temperature is proposed. The dynamic mechanical properties of the material under different strain rates and temperature conditions are obtained by quasi-static compression test and split Hopkinson pressure bar (SHPB) test. The coefficients of the modified J-C model are obtained by the linear regression method. The modified model is verified by comparison with experimental and model prediction results. The results show that the modified J-C model proposed in this paper can accurately describe the mechanical properties of nickel-based powder metallurgy superalloys at high temperatures and high strain rates. This provides help for studying the cutting mechanism and finite element simulation of nickel-based powder metallurgy superalloy.

2.
J Orthop Surg Res ; 19(1): 173, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454405

RESUMO

BACKGROUND: The current literature shows that dyslipidemia can lead to a higher incidence of rotator cuff tears (RCTs) and an increased retear rate after repair. We aimed to evaluate the influence of preoperative dyslipidemia on postoperative pain, patient-reported outcomes (PROs), active range of motion (ROM), and structural integrity. METHODS: A cohort of 111 patients who underwent arthroscopic RCT repair between January 2021 and July 2022, and whose complete preoperative serum lipid data were available within one week prior to surgery was retrospectively reviewed. Dyslipidemia was defined as the presence of an increase or decrease in at least one blood lipid profile (triglycerides, total cholesterol, low-density lipoprotein, high-density lipoprotein, or non-high-density lipoprotein). There were 43 patients in the dyslipidemia group and 68 in the ortholiposis group. Patient evaluations, including pain score, PROs, and ROMs, were conducted preoperatively; at 3 and 6 months postoperatively; and at the last follow-up. Structural integrity was assessed by magnetic resonance imaging (MRI) 6 months after surgery if possible, and Sugaya type 4 or 5 was considered a retear. Propensity score matching (PSM) was used to reduce bias. RESULTS: The RCT size, surgical technique, preoperative pain status, PROs, and active ROM were comparable between patients with dyslipidemia and those with ortholiposis. Three months after surgery, patients in the dyslipidemia group had worse average PROs (Constant score: P = 0.001; ASES score: P = 0.012; UCLA score: P = 0.015), forward flexion (P = 0.012), and internal rotation (P = 0.001) than patients in the ortholiposis group did. The difference between the two groups persisted after PSM but disappeared at the sixth month after surgery. No significant differences in pain score, PROs, or active ROMs were detected between the dyslipidemia and ortholiposis groups after a mean follow-up of 24 months. Of the 72 patients who underwent MRI, 4 retears (5.6%) were found, and all were in the ortholiposis group. There was no difference in the rate of retears between the two groups (P = 0.291) or with (P = 0.495) PSM. CONCLUSIONS: In conclusion, we found that perioperative dyslipidemia may impact initial recovery within the first 3 months following arthroscopic rotator cuff repair but may have no effect on pain, PROs, or active ROMs at a mean 2-year follow-up or rotator cuff integrity at 6 months postoperatively. Trail registration Retrospectively registered.


Assuntos
Dislipidemias , Lesões do Manguito Rotador , Humanos , Manguito Rotador/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Lesões do Manguito Rotador/diagnóstico por imagem , Lesões do Manguito Rotador/cirurgia , Artroscopia/métodos , Imageamento por Ressonância Magnética , Amplitude de Movimento Articular , Dor Pós-Operatória/etiologia , Lipídeos
3.
Metabolites ; 14(3)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38535302

RESUMO

A large number of dead seedlings can occur in saline soils, which seriously affects the large-scale cultivation of rice. This study investigated the effects of plant growth regulators (PGRs) and nitrogen application on seedling growth and salt tolerance (Oryza sativa L.), which is of great significance for agricultural production practices. A conventional rice variety, "Huang Huazhan", was selected for this study. Non-salt stress treatments included 0% NaCl (CK treatment), CK + 0.05 g N/pot (N treatment), CK + 40 mg·L-1 5-aminolevulinic acid (5-ALA) (A treatment), and CK + 30 mg·L-1 diethylaminoethyl acetate (DTA-6) (D treatment). Salt stress treatments included 0.3% NaCl (S treatment), N + 0.3% NaCl (NS treatment), A + 0.3% NaCl (AS treatment), and D + 0.3% NaCl (DS treatment). When 3 leaves and 1 heart emerged from the soil, plants were sprayed with DTA-6 and 5-ALA, followed by the application of 0.3% NaCl (w/w) to the soil after 24 h. Seedling morphology and photosynthetic indices, as well as carbohydrate metabolism and key enzyme activities, were determined for each treatment. Our results showed that N, A, and D treatments promoted seedling growth, photosynthesis, carbohydrate levels, and the activities of key enzymes involved in carbon metabolism when compared to the CK treatment. The A treatment had the most significant effect, with increases in aboveground dry weight and net photosynthetic rates (Pn) ranging from 17.74% to 41.02% and 3.61% to 32.60%, respectively. Stomatal limiting values (Ls) significantly decreased from 19.17% to 43.02%. Salt stress significantly inhibited seedling growth. NS, AS, and DS treatments alleviated the morphological and physiological damage of salt stress on seedlings when compared to the S treatment. The AS treatment was the most effective in improving seedling morphology, promoting photosynthesis, increasing carbohydrate levels, and key enzyme activities. After AS treatment, increases in aboveground dry weight, net photosynthetic rate, soluble sugar content, total sucrose synthase, and amylase activities were 17.50% to 50.79%, 11.39% to 98.10%, 20.20% to 80.85%, 21.21% to 33.53%, and 22.17% to 34.19%, respectively, when compared to the S treatment. In summary, foliar sprays of 5-ALA, DTA-6, and additional nitrogen fertilizer enhanced rice seedling growth, increased photosynthesis, lowered Ls values, and improved seedling salt tolerance. Spraying two regulators, 5-ALA and DTA-6, quantitatively increased the effect of nitrogen fertilizer, with comparable effects on NaCl stress regulation. This study provides the basis for efficient agricultural production.

4.
J Med Internet Res ; 26: e45406, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38407948

RESUMO

BACKGROUND: Low back pain is one of the most prevalent pain conditions worldwide. Virtual reality-based training has been used for low back pain as a new treatment strategy. Present evidence indicated that the effectiveness of virtual reality-based training for people with chronic low back pain is inconclusive. OBJECTIVE: This study conducted a meta-analysis to evaluate the immediate- and short-term effects of virtual reality-based training on pain, pain-related fear, and disability in people with chronic low back pain. METHODS: We searched the PubMed, Embase, Web of Science, PEDro, CENTRAL, and CINAHL databases from inception until January 2024. Only randomized controlled trials assessing the effects of virtual reality-based training on individuals with chronic low back pain were selected. The outcomes were focused on pain, pain-related fear measured by the Tampa Scale of Kinesiophobia, and disability measured by the Oswestry Disability Index. The immediate term was defined as the immediate period after intervention, and the short term was defined as 3 to 6 months after intervention. The Cochrane Risk of Bias tool and the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach were used to evaluate the quality of the methodology and evidence, respectively. RESULTS: In total, 20 randomized controlled trials involving 1059 patients were eligible for analysis. Virtual reality-based training showed significant improvements in pain (mean difference [MD] -1.43; 95% CI -1.86 to -1.00; I2=95%; P<.001), pain-related fear using the Tampa Scale of Kinesiophobia (MD -5.46; 95% CI -9.40 to 1.52; I2=90%; P=.007), and disability using the Oswestry Disability Index (MD -11.50; 95% CI -20.00 to -3.01; I2=95%; P=.008) in individuals with chronic low back pain immediately after interventions. However, there were no significant differences observed in pain (P=.16), pain-related fear (P=.10), and disability (P=.43) in the short term. CONCLUSIONS: These findings indicated that virtual reality-based training can be used effectively for individuals with chronic low back pain in the immediate term, especially to reduce pain, alleviate pain-related fear, and improve disability. However, the short-term benefits need more high-quality trials to be demonstrated. TRIAL REGISTRATION: PROSPERO CRD42021292633; http://tinyurl.com/25mydxpz.


Assuntos
Dor Lombar , Transtornos Fóbicos , Realidade Virtual , Humanos , Dor Lombar/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto , Bases de Dados Factuais
5.
J Control Release ; 368: 444-452, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38401849

RESUMO

Among non-viral gene delivery vectors, poly(ß-amino ester)s (PAEs) are one of the most versatile candidates because of their wide monomer availability, high polymer flexibility, and superior gene transfection performance both in vitro and in vivo. Over two decades, PAEs have evolved from linear to highly branched structures, significantly enhancing gene delivery efficacy. Building on the proven efficient sets of monomers in highly branched PAEs (HPAEs), this work introduced a new class of cyclic PAEs (CPAEs) constructed via an A2 + B4 + C2 cyclization synthesis strategy and identified their markedly improved gene transfection capabilities in gene delivery applications. Two sets of cyclic PAEs (CPAEs) with rings of different sizes and topologies were obtained. Their chemical structures were confirmed via two-dimensional nuclear magnetic resonance and the photoluminescence phenomena, and their DNA delivery behaviours were investigated and compared with the HPAE counterparts. In vitro assessments demonstrated that the CPAEs with a macrocyclic architecture (MCPAEs), significantly enhanced DNA intracellular uptake and facilitated efficient gene expression while maintaining perfect biocompatibility. The top-performance MCPAEs have been further employed to deliver a plasmid coding dual single guide RNA-guided CRISPR-Cas9 machinery to delete COL7A1 exon 80 containing the c.6527dupC mutation. In recessive dystrophic epidermolysis bullosa (RDEB) patient-derived epidermal keratinocytes, MCPAEs facilitated the CRISPR plasmid delivery and achieved efficient targeted gene editing in multiple colonies.


Assuntos
Ésteres , Edição de Genes , Polímeros , Humanos , Edição de Genes/métodos , Ciclização , RNA Guia de Sistemas CRISPR-Cas , DNA/metabolismo , Sistemas CRISPR-Cas/genética , Colágeno Tipo VII/genética
6.
Heliyon ; 10(3): e25606, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38356591

RESUMO

Background: The efficacy of Kinesio tape (KT) in lateral elbow tendinopathy (LET) has been widely discussed, but controversy remains. Objectives: To perform a meta-analysis of randomized controlled trials (RCTs) in the literature to ascertain the efficacy of KT in LET. Design: Systematic review and meta-analysis. Method: Two independent reviewers carried out a literature search in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Any discrepancies were addressed by a third author. Included in the study were RCTs comparing KT to a control group in the context of LET. The quality of evidence was assessed with the 2.0 version of Cochrane Collaboration risk of bias tool. Evaluation centered on clinical outcomes, such as function scores and pain, with comparison made using the risk ratio for dichotomous variables and the mean difference for continuous variables. Statistical significance was considered for P values < 0.05. Results: Included in this review are 11 RCTs with 562 patients. Significant results were noted in favor of KT compared with control based on the visual analog scale score at movement (SMD = -1.17; P = 0.03); visual analog scale score at movement (SMD = -1.08; P < 0.00001); maximal grip strength (SMD = 0.69; P < 0.00001); pain pressure threshold (SMD = 1.14; P < 0.00001); Patient-Rated Tennis Elbow Evaluation Questionnaire score (SMD = -1.16; P = 0.02) and Disabilities of the Arm, Shoulder, and Hand questionnaire score (SMD = -1.19; P < 0.00001). Conclusion: The current evidence shows that KT can improve pain levels and the function of elbow joint in patients with LET, and this improvement is might be clinically significant. We assume that physiotherapists can consider trying the KT in LET patients. Future quality studies are needed to confirm the efficacy and explore the mechanism of KT.

7.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 36(1): 23-27, 2024 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-38404267

RESUMO

OBJECTIVE: To explore the current situation and influencing factors of quality of life of septic patients in intensive care unit (ICU) after discharge, and to provide theoretical basis for clinical early psychological intervention and continuity of care. METHODS: A prospective observational study was conducted. The septic patients who were hospitalized in the department of critical care medicine of the Affiliated Hospital of Jining Medical University and discharged with improvement from January 1 to December 31, 2022 were selected as the research objects. The demographic information, basic diseases, infection site, vital signs at ICU admission, severity scores of the condition within 24 hours after ICU admission, various biochemical indexes, treatment process, and prognostic indexes of all the patients were recorded. All patients were assessed by questionnaire at 3 months of discharge using the 36-item short-form health survey scale (SF-36 scale), the activities of daily living scale (ADL scale), and the Montreal cognitive assessment scale (MoCA scale). Multiple linear regression was used to analyze the factors influencing the quality of life of septic patients after discharge from the hospital. RESULTS: A total of 200 septic patients were discharged with improvement and followed up at 3 months of discharge, of which 150 completed the questionnaire. Of the 150 patients, 57 had sepsis and 93 had septic shock. The total SF-36 scale score of septic patients at 3 months of discharge was 81.4±23.0, and the scores of dimensions were, in descending order, role-emotional (83.4±23.0), mental health (82.9±23.6), bodily pain (82.8±23.3), vitality (81.6±23.2), physical function (81.4±23.5), general health (81.1±23.3), role-physical (79.5±27.0), and social function (78.8±25.2). There was no statistically significant difference in the total SF-36 scale score between the patients with sepsis and septic shock (82.6±22.0 vs. 80.7±23.6, P > 0.05). Incorporating the statistically significant indicators from linear univariate analysis into multiple linear regression analysis, and the results showed that the factors influencing the quality of life of septic patients at 3 months after discharge included ADL scale score at 3 months after discharge [ß= 0.741, 95% confidence interval (95%CI) was 0.606 to 0.791, P < 0.001], length of ICU stay (ß= -0.209, 95%CI was -0.733 to -0.208, P = 0.001), duration of mechanical ventilation (ß= 0.147, 95%CI was 0.122 to 0.978, P = 0.012), total dosage of norepinephrine (ß= -0.111, 95%CI was -0.044 to -0.002, P = 0.028), mean arterial pressure (MAP) at ICU admission (ß= -0.102, 95%CI was -0.203 to -0.007, P = 0.036) and body weight (ß= 0.097, 95%CI was 0.005 to 0.345, P = 0.044). CONCLUSIONS: The quality of life of patients with sepsis at 3 months after discharge is at a moderately high level. The influencing factors of the quality of life of patients with sepsis at 3 months after discharge include the ADL scale score at 3 months after discharge, the length of ICU stay, the duration of mechanical ventilation, the total dosage of norepinephrine, MAP at ICU admission and body weight, and healthcare professionals should enhance the treatment and care of the patients during their hospitalization based on the above influencing factors, and pay attention to early psychological intervention and continued care for such patients.


Assuntos
Sepse , Choque Séptico , Humanos , Choque Séptico/terapia , Qualidade de Vida , Atividades Cotidianas , Sepse/psicologia , Unidades de Terapia Intensiva , Prognóstico , Norepinefrina , Sobreviventes , Peso Corporal
8.
J Control Release ; 367: 327-338, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38272397

RESUMO

Gene therapy holds great potential for treating Lung Cystic Fibrosis (CF) which is a fatal hereditary condition arising from mutations in the CF transmembrane conductance regulator (CFTR) gene, resulting in dysfunctional CFTR protein. However, the advancement and clinical application of CF gene therapy systems have been hindered due to the absence of a highly efficient delivery vector. In this work, we introduce a new generation of highly branched poly(ß-amino ester) (HPAE) gene delivery vectors for CF treatment. Building upon the classical chemical composition of HPAE, a novel backbone cationization strategy was developed to incorporate additional functional amine groups into HPAE without altering their branching degree. By carefully adjusting the type, proportion, and backbone distribution of the added cationic groups, a series of highly effective HPAE gene delivery vectors were successfully constructed for CF disease gene therapy. In vitro assessment results showed that the backbone cationized HPAEs with randomly distributed 10% proportion of 1-(3-aminopropyl)-4-methylpiperazine (E7) amine groups exhibited superior transfection performance than their counterparts. Furthermore, the top-performed backbone cationized HPAEs, when loaded with therapeutic plasmids, successfully reinstated CFTR protein expression in the CFBE41o- disease model, achieving levels 20-23 times higher than that of normal human bronchial epithelial (HBE) cells. Their therapeutic effectiveness significantly surpassed that of the currently advanced commercial vectors, Xfect and Lipofectamine 3000.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística , Terapia Genética , Humanos , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Polímeros/química , Aminas , Vetores Genéticos/genética
9.
Biomater Sci ; 12(2): 330-334, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38173335

RESUMO

A ratiometric fluorescent probe (MeO-CNPPV Pdots) based on the principle of fluorescence resonance energy transfer (FRET) was designed for hypochlorous acid (HOCl) and rheumatoid arthritis (RA) detection. The presence of HOCl can block the energy transfer from CNPPV to MeOTPATBT, resulting in a ratio change in the fluorescence of Pdots (I600 nm/I680 nm). This strategy provides a valuable paradigm in early RA evaluation.


Assuntos
Corantes Fluorescentes , Ácido Hipocloroso , Transferência Ressonante de Energia de Fluorescência/métodos
10.
Heliyon ; 10(1): e23371, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38163114

RESUMO

In the present study, we demonstrated that the presence of cysteine could remarkably enhance the degradation of atrazine by Fe3O4/persulfate system. The results of electron paramagnetic resonance (EPR) spectra confirmed the combination of cysteine and Fe3O4 exhibited much higher activity on activation of persulfate to generate more SO4•- and •OH than Fe3O4 alone. At pH of 3.0, SO4•- and •OH contributed to about 58.2 % and 41.8 % of atrazine removal respectively, while •OH gradually dominated the oxidation of atrazine from neutral condition to alkaline condition. The co-existing Cl- and HCO3- could quench SO4•-, resulting in the inhibition of atrazine degradation. The presence of low natural organic matters (NOM) concentration (0-2 mg L-1) could enhance the atrazine removal, and high concentration (>5 mg L-1) of NOM restrained the atrazine degradation. During the Cysteine/Fe3O4/Persulfate process, cysteine served as a complexing reagent and reductant. Through acidolysis and complexation, Fe3O4 could release dissolved and surface bound Fe2+, both of which contributed to the activation of persulfate together. Meanwhile, cysteine was not rapidly consumed due to a regeneration process, which was beneficial for maintaining Fe2+/Fe3+ cycle and constantly accelerating the activation of persulfate for atrazine degradation. The reused Fe3O4 and cysteine in the Cysteine/Fe3O4/Persulfate process exhibited high stability for the atrazine degradation after three cycles. The degradation pathway of atrazine included alkylic-oxidation, dealkylation, dechlorination-hydroxylation processes. The present study indicates the novel Cysteine/Fe3O4/Persulfate process might be a high potential for treatment of organic polluted water.

11.
Arthroscopy ; 40(2): 553-566, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37315745

RESUMO

PURPOSE: To systematically review the current evidence to compare the differences in outcomes of the suture button (SB) versus hook plate (HP) fixations for treating acute acromioclavicular joint dislocation (ACD). METHODS: Two independent reviewers performed the literature search based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A literature search of the Embase, PubMed, and Cochrane Library databases was performed and Level I-IV evidence studies comparing the SB and HP procedures for acute ACD were included. Studies that met the following exclusion criteria were excluded: (1) letters, comments, case reports, reviews, animal studies, cadaveric studies, biomechanical studies, and study protocols; (2) incomplete data; and (3) repeated studies and data. The Newcastle-Ottawa Scale was used to evaluate the quality of nonrandomized studies. Constant score, visual analog scale (VAS) score, operation time, coracoclavicular distance (CCD), and complications were recorded and the mean differences of VAS and Constant were compared with preset minimal clinically important difference. RESULTS: Fourteen studies with 363 patients treated with SB procedures and 432 patients with the HP procedure were included. In terms of patient-reported outcomes, 5 of the 13 included studies reported significantly greater Constant score in SB group and most (4/5) used arthroscopic SB technique. Statistically significant differences in favor of SB were found in 3 of the 7 included studies in terms of VAS score whereas none of them reached the minimal clinically important difference. In terms of recurrent instability, no statistically significant difference was noted. All studies showed that the SB technique resulted in lower estimated blood loss. No difference was detected in CCD and complications. CONCLUSIONS: Based on the current body of evidence, it is suggested that employment of the SB technique may confer advantageous outcomes when compared to the HP technique in acute ACD patients. These potential benefits may include higher Constant scores, lower pain levels, and no discernible increases in operation time, CCD, or complication rates. LEVEL OF EVIDENCE: Level IV, systematic review of Level II-IV studies.


Assuntos
Articulação Acromioclavicular , Luxações Articulares , Luxação do Ombro , Humanos , Luxações Articulares/cirurgia , Articulação Acromioclavicular/cirurgia , Resultado do Tratamento , Luxação do Ombro/cirurgia , Placas Ósseas , Suturas , Dor
12.
Adv Mater ; 36(4): e2306687, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37649133

RESUMO

Manipulating the coordination environment of individual active sites in a precise manner remains an important challenge in electrocatalytic reactions. Herein, inspired by theoretical predictions, a facile procedure to synthesize a series of symmetry-breaking zinc metal-organic framework (Zn-MOF) catalysts with well-defined structures is presented. Benefiting from the optimized coordination microenvironment regulated by symmetry-breaking, Zn-N2 S2 -MOF exhibits the best performance of nitrogen (N2 ) reduction reaction (NRR) with NH3 yield rate of 25.07 ± 1.57 µg h-1  cm-2 and Faradaic efficiency of 44.57 ± 2.79% compared with reported Zn-based NRR catalysts. X-ray absorption near-edge structure shows that the symmetry-breaking distorts the coordination environment and modulates the delocalized electrons around the Zn sites, which favors the formation of unpaired low-valence Znδ+ , thereby facilitating the adsorption/activation of N2 . Theoretical calculations elucidate that low-valence Znδ+ in Zn-N2 S2 -MOF can effectively lower the energy barrier of potential determining step, promoting the kinetics and boosting the NRR activity. This work highlights the relationship between the precise coordination environment of metal sites and the catalytic activity, which offers insightful guidance for rationally designing high-efficiency electrocatalysts.

13.
Magn Reson Med ; 91(5): 1893-1907, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38115573

RESUMO

PURPOSE: The inflow-based vascular-space-occupancy (iVASO) MRI was originally developed in a single-slice mode to measure arterial cerebral blood volume (CBVa). When vascular crushers are applied in iVASO, the signals can be sensitized predominantly to small pial arteries and arterioles. The purpose of this study is to perform a systematic optimization and evaluation of a 3D iVASO sequence on both 3 T and 7 T for the quantification of CBVa values in the human brain. METHODS: Three sets of experiments were performed in three separate cohorts. (1) 3D iVASO MRI protocols were compared to single-slice iVASO, and the reproducibility of whole-brain 3D iVASO MRI was evaluated. (2) The effects from different vascular crushers in iVASO were assessed. (3) 3D iVASO MRI results were evaluated in arterial and venous blood vessels identified using ultrasmall-superparamagnetic-iron-oxides-enhanced MRI to validate its arterial origin. RESULTS: 3D iVASO scans showed signal-to-noise ratio (SNR) and CBVa measures consistent with single-slice iVASO with reasonable intrasubject reproducibility. Among the iVASO scans performed with different vascular crushers, the whole-brain 3D iVASO scan with a motion-sensitized-driven-equilibrium preparation with two binomial refocusing pulses and an effective TE of 50 ms showed the best suppression of macrovascular signals, with a relatively low specific absorption rate. When no vascular crusher was applied, the CBVa maps from 3D iVASO scans showed large CBVa values in arterial vessels but well-suppressed signals in venous vessels. CONCLUSION: A whole-brain 3D iVASO MRI scan was optimized for CBVa measurement in the human brain. When only microvascular signals are desired, a motion-sensitized-driven-equilibrium-based vascular crusher with binomial refocusing pulses can be applied in 3D iVASO.


Assuntos
Volume Sanguíneo Cerebral , Imageamento por Ressonância Magnética , Humanos , Reprodutibilidade dos Testes , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Circulação Cerebrovascular , Artérias
14.
J Mater Chem B ; 12(2): 508-524, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38108579

RESUMO

Poly(lactide-co-glycolide) (PLGA) and calcium sulfate composites are promising biodegradable biomaterials but are still challenging to use in people with high levels of blood glucose or diabetes. To date, the influence of glucose on their degradation has not yet been elucidated and thus calls for more research attention. Herein, a novel calcium sulfate whisker with L-arginine was used to effectively tune its crystal morphology and was employed as a reinforced phase to construct the PLGA-based composite scaffolds (ArgCSH/PLGA) with a sleeve porous structure. ArgCSH/PLGA showed excellent elastic modulus and strength in the compression and bending models. Moreover, an in vitro immersion test showed that ArgCSH/PLGA possessed degradation and redeposition behaviors sensitive to glucose concentration, and the adsorbed Arg played a crucial role in the degradation process. The subsequent cell functional evaluation showed that ArgCSH could effectively protect cells from damage caused by AGEs and promote osteogenic differentiation. The corresponding degradation products of ArgCSH/PLGA displayed the ability to regulate osteoblast bone differentiation and accelerate matrix mineralization. These findings provide new insights into the interaction between biomaterials and the physiological environment, which may be useful in expanding the targeted choice of efficient bone graft biodegradable materials for diabetic osteoporosis.


Assuntos
Osteogênese , Poliglactina 910 , Humanos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Poliglactina 910/química , Sulfato de Cálcio , Ácido Poliglicólico/química , Ácido Láctico/química , Arginina/farmacologia , Materiais Biocompatíveis/farmacologia , Materiais Biocompatíveis/química
15.
J Phys Chem A ; 127(50): 10709-10716, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38055927

RESUMO

Ring-opening enthalpy (ΔHROP) is a fundamental thermodynamic quantity controlling the polymerization and depolymerization of an important class of recyclable polymers, namely, those created from ring-opening polymerization (ROP). Highly accurate first-principles-based computational methods to compute ΔHROP are computationally too demanding to efficiently guide the design of depolymerizable polymers. In this work, we develop a generalizable machine-learning model that was trained on experimental measurements and reliably computed simulation results of ΔHROP (the latter provides a pathway to systematically increase the chemical diversity of the data). Predictions of ΔHROP using this machine-learning model require essentially no time while the prediction accuracy is about ∼8 kJ/mol, approaching the well-known chemical accuracy. We hope that this effort will contribute to the future development of new depolymerizable polymers.

16.
J Clin Med ; 12(23)2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38068415

RESUMO

BACKGROUND: Carpal tunnel syndrome (CTS) is the most common entrapment syndrome, primarily affecting women between the ages of 40 and 70, and conservative treatments are the first option for mild-to-moderate CTS. However, the comparisons between extracorporeal shock wave therapy (ESWT) and other non-surgical methods in the treatment of mild-to-moderate CTS remain controversial, and an updated systematic review is needed. METHODS: An electronic search was performed, and all available articles until August 2023 were included in the analysis. The overall quality of evidence was assessed by the GRADE approach. Meta-analyses were conducted using Manager V.5.3.3. Pooled effect sizes were expressed as the weighted mean difference (WMD) with 95% confidence intervals (CIs). RESULTS: A total of 19 RCTs were included. Low-level quality evidence showed that ESWT outperformed the control intervention in terms of functional improvements, pain relief, electrodiagnostic parameters, and cross-sectional area of the median nerve at any time point of follow-up. Compared to local corticosteroid injection (LCI), there were statistically better improvements in functional improvements, pain relief, and electrodiagnostic parameters at 3 and 6 months of follow-up. CONCLUSIONS: There is low-level quality evidence to show that both fESWT and rESWT are more clinically effective than controls in symptom relief, functional enhancement, and electrophysiologic parameters' improvement for patients with mild-to-moderate CTS at any time point of follow-up. Compared with LCI, ESWT yielded similar short-term (<1 month) but better medium- (1-6 months) and long-term (>6 months) improvements in pain relief and functional recovery with fewer potential complications.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38083559

RESUMO

Auditory attention decoding (AAD) is a technique used to identify and amplify the talker that a listener is focused on in a noisy environment. This is done by comparing the listener's brainwaves to a representation of all the sound sources to find the closest match. The representation is typically the waveform or spectrogram of the sounds. The effectiveness of these representations for AAD is uncertain. In this study, we examined the use of self-supervised learned speech representation in improving the accuracy and speed of AAD. We recorded the brain activity of three subjects using invasive electrocorticography (ECoG) as they listened to two conversations and focused on one. We used WavLM to extract a latent representation of each talker and trained a spatiotemporal filter to map brain activity to intermediate representations of speech. During the evaluation, the reconstructed representation is compared to each speaker's representation to determine the target speaker. Our results indicate that speech representation from WavLM provides better decoding accuracy and speed than the speech envelope and spectrogram. Our findings demonstrate the advantages of self-supervised learned speech representation for auditory attention decoding and pave the way for developing brain-controlled hearable technologies.


Assuntos
Córtex Auditivo , Percepção da Fala , Humanos , Fala , Estimulação Acústica/métodos , Atenção
18.
Clin Appl Thromb Hemost ; 29: 10760296231220054, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38130118

RESUMO

PURPOSE: To evaluate the efficacy and safety of ultrasound-guided femoral nerve block (FNB) in treating great saphenous vein (GSV) insufficiency by endovenous radiofrequency ablation (EVRA) combined with punctate stripping (PS). METHODS: This was a single-center, retrospective cohort study. A total of 135 patients were divided into Group A (59 patients) and Group B (76 patients). All patients received tumescent anesthesia during the operation, and group A received an additional ultrasound-guided FNB before the procedure. Intraoperative and postoperative pain score, the volume of tumescent anesthesia solution (TAS), and other indicators were compared in two groups. RESULTS: Group A had a significantly lower intraoperative pain visual analog scale than group B (2.7 ± 1.2 vs 5.2 ± 1.5, P < 0.001). The volume of TAS in group A was significantly lower than that in group B (198 ± 26.6 ml vs 338 ± 34.7 ml, P < 0.001). Postoperative muscle strength of group A was significantly decreased compared with group B (54.2% vs 3.90%, P < 0.001); no patient had severe limitation of active movements in both groups, and all motor blocks recovered within 24 h. The incidence of skin ecchymosis in group A was lower than that in group B (18.6% vs 46.1%, P = 0.001). The operation duration of the two groups had no statistically significant difference. CONCLUSIONS: Ultrasound-guided FNB in treating GSV insufficiency by EVRA combined with PS significantly relieved intraoperative pain and reduced the dosage of TAS and the incidence of skin ecchymosis without increasing the complications of anesthesia or any other surgical complications.


Assuntos
Ablação por Radiofrequência , Varizes , Insuficiência Venosa , Humanos , Nervo Femoral , Estudos Retrospectivos , Equimose/complicações , Veia Safena/cirurgia , Resultado do Tratamento , Dor Pós-Operatória/etiologia , Ablação por Radiofrequência/efeitos adversos , Varizes/complicações , Varizes/cirurgia , Insuficiência Venosa/cirurgia , Insuficiência Venosa/complicações
19.
Artigo em Inglês | MEDLINE | ID: mdl-38153106

RESUMO

BACKGROUND: Diffuse-type tenosynovial giant-cell tumor (D-TGCT), formerly known as pigmented villonodular synovitis, is a rare, locally aggressive, invasive soft tissue tumor that primarily occurs in the knee. Surgical excision is the main treatment option, but there is a high recurrence rate. Arthroscopic surgical techniques are emphasized because they are less traumatic and offer faster postoperative recovery, but detailed reports on arthroscopic techniques and outcomes of D-TGCT in large cohorts are still lacking. QUESTIONS/PURPOSES: (1) What is the recurrence rate of knee D-TGCT after multiportal arthroscopic synovectomy? (2) What are the complications, knee ROM, pain score, and patient-reported outcomes for patients, and do they differ between patients with and without recurrence? (3) What factors are associated with recurrence after arthroscopic treatment in patients with D-TGCT? METHODS: In this single-center, retrospective study conducted between January 2010 and April 2021, we treated 295 patients with knee D-TGCTs. We considered patients undergoing initial surgical treatment with multiportal arthroscopic synovectomy as potentially eligible. Based on that, 27% (81 of 295) of patients were excluded because of recurrence after synovectomy performed at another institution. Of the 214 patients who met the inclusion criteria, 17% (36 of 214) were lost to follow-up, leaving 83% (178 of 214) of patients in the analysis. Twenty-eight percent (50 of 178) of patients were men and 72% (128 of 178) were women, with a median (range) age of 36 years (7 to 69). The median follow-up duration was 80 months (26 to 149). All patients underwent multiportal (anterior and posterior approaches) arthroscopic synovectomy, and all surgical protocols were determined by discussion among four surgeons after preoperative MRI. A combined open posterior incision was used for patients with lesions that invaded or surrounded the blood vessels and nerves or invaded the muscle space extraarticularly. Standard postoperative adjuvant radiotherapy was recommended for all patients with D-TGCT who had extraarticular and posterior compartment invasion; for patients with only anterior compartment invasion, radiotherapy was recommended for severe cases as assessed by the surgeons and radiologists based on preoperative MRI and intraoperative descriptions. Postoperative recurrence at 5 years was calculated using a Kaplan-Meier survivorship estimator. The WOMAC score (0 to 96, with higher scores representing a worse outcome; minimum clinically important difference [MCID] 8.5), the Lysholm knee score (0 to 100, with higher scores being better knee function; MCID 25.4), the VAS for pain (0 to 10, with higher scores representing more pain; MCID 2.46), and knee ROM were used to evaluate functional outcomes. Because we did not have preoperative patient-reported outcomes scores, we present data on the proportion of patients who achieved the patient-acceptable symptom state (PASS) for each of those outcome metrics, which were 14.6 of 96 points on the WOMAC, 52.5 of 100 points on the Lysholm, and 2.32 of 10 points on the VAS. RESULTS: The symptomatic or radiographically documented recurrence at 5 years was 12% (95% confidence interval [CI] 7% to 17%) using the Kaplan-Meier estimator, with a mean recurrence time of 33 ± 19 months. Of these, three were asymptomatic recurrences found during regular MRI reviews, and the remaining 19 underwent repeat surgery. There was one intraoperative complication (vascular injury) with no effect on postoperative limb function and eight patients with postoperative joint stiffness, seven of whom improved with prolonged rehabilitation and one with manipulation under anesthesia. No postradiotherapy complications were found. The proportion of patients who achieved the preestablished PASS was 99% (176 of 178) for the VAS pain score, 97% (173 of 178) for the WOMAC score, and 100% (178 of 178) for the Lysholm score. A lower percentage of patients with recurrence achieved the PASS for WOMAC score than patients without recurrence (86% [19] versus 99% [154], OR 0.08 [95% CI 0.01 to 0.52]; p = 0.01), whereas no difference was found in the percentage of VAS score (95% [21] versus 99% [155], OR 0.14 [95% CI 0.01 to 2.25]; p = 0.23) or Lysholm score (100% [22] versus 100% [156], OR 1 [95% CI 1 to 1]; p = 0.99). Moreover, patients in the recurrence group showed worse knee flexion (median 135° [100° to 135°] versus median 135° [80° to 135°]; difference of medians 0°; p = 0.03), worse WOMAC score (median 3.5 [0 to 19] versus median 1 [0 to 29]; difference of medians 2.5; p = 0.01), and higher VAS pain score (median 1 [0 to 4] versus median 0 [0 to 4]; difference of medians 1; p < 0.01) than those in the nonrecurrence group, although no differences reached the MCID. No factors were associated with D-TGCT recurrence, including the use of postoperative radiotherapy, surgical technique, and invasion extent. CONCLUSION: This single-center, large-cohort retrospective study confirmed that multiportal arthroscopic surgery can be used to treat knee D-TGCTs with a low recurrence rate, few complications, and satisfactory postoperative outcomes. Surgeons should conduct a thorough preoperative evaluation, meticulous arthroscopic synovectomy, and regular postoperative follow-up when treating patients with D-TGCT to reduce postoperative recurrence. Because the available evidence does not appear to fully support the use of postoperative adjuvant radiotherapy in all patients with D-TGCTs and our study design is inadequate to resolve this controversial issue, future studies should look for more appropriate indications for radiotherapy, such as planning based on a more precise classification of lesion invasion. LEVEL OF EVIDENCE: Level III, therapeutic study.

20.
ACS Biomater Sci Eng ; 9(12): 6734-6744, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-37939039

RESUMO

Poly(vinyl alcohol) (PVA) exhibits a wide range of potential applications in the biomedical field due to its favorable mechanical properties and biocompatibility. However, few studies have been carried out on selective laser sintering (SLS) of PVA due to its poor thermal processability. In this study, in order to impart PVA powder the excellent thermal processability, the molecular complexation technology was performed to destroy the strong hydrogen bonds in PVA and thus significantly reduced the PVA melting point and crystallinity to 190.9 °C and 27.9%, respectively. The modified PVA (MPVA) was then compounded with hydroxyapatite (HA) to prepare PVA/HA composite powders suitable for SLS 3D printing. The final SLS 3D-printed MPVA/HA composite porous scaffolds show high precision and interconnected pores with a porosity as high as 68.3%. The in vitro cell culture experiments revealed that the sintered composite scaffolds could significantly promote the adhesion and proliferation of osteoblasts and facilitate bone regeneration, and the quantitative real-time polymerase chain reaction results further demonstrate that the printed MPVA/20HA scaffold could significantly enhance the expression levels of both early osteogenic-specific marker of alkaline phosphatase stain and runt-related transcription factor 2. Meanwhile, in in vivo experiments, it is encouragingly found that the resultant MPVA/20HA SLS 3D-printed part has an obvious effect on promoting the growth of new bone tissue as well as a better bone regeneration capability. This work could provide a promising strategy for fabrication of PVA scaffolds through SLS 3D printing, exhibiting a great potential for clinical applications in bone tissue engineering.


Assuntos
Durapatita , Tecidos Suporte , Durapatita/farmacologia , Durapatita/química , Tecidos Suporte/química , Porosidade , Álcool de Polivinil/química , Etanol , Impressão Tridimensional
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