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1.
Food Chem ; 448: 139112, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38569404

RESUMO

Ginseng is a most popular health-promoting food with ginsenosides as its main bioactive ingredients. Illegal sulfur-fumigation causes ginsenosides convert to toxic sulfur-containing derivatives, and reduced the efficacy/safety of ginseng. 24-sulfo-25-ene ginsenoside Rg1 (25-ene SRg1), one of the sulfur-containing derivatives, is a potential quality control marker of fumigated ginseng, but with low accessibility owing to its unknown generation mechanism. In this study, metals/bisulfite system involved generation mechanism was investigated and verified. The generation of 25-ene SRg1 in sulfur-fumigated ginseng is that SO2, formed during sulfur-fumigation, reacted with water and ionized into HSO3-. On the one hand, under the metals/bisulfite system, HSO3- generates HSO5- and free radicals which converted ginsenoside Rg1 to 24,25-epoxide Rg1; on the other hand, as a nucleophilic group, HSO3- reacted with 24,25-epoxide Rg1 and further dehydrated to 25-ene SRg1. This study provided a technical support for the promotion of 25-ene SRg1 as the characteristic quality control marker of sulfur-fumigated ginseng.


Assuntos
Fumigação , Ginsenosídeos , Panax , Controle de Qualidade , Enxofre , Ginsenosídeos/química , Ginsenosídeos/análise , Panax/química , Enxofre/química , Sulfitos/química , Sulfitos/análise , Metais/química , Metais/análise , Extratos Vegetais/química
2.
Org Lett ; 26(16): 3355-3360, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38604973

RESUMO

A two-step protocol for the conversion of alkyl-substituted alkynes to 1,3-enynes is reported. In this α-methenylation process, an iron-catalyzed propargylic C-H functionalization delivers tetramethylpiperidine-derived homopropargylic amines which undergo facile Cope elimination upon N-oxidation to afford the enyne products. A range of aryl alkyl and dialkyl acetylenes were found to be suitable substrates for this process, which constitutes an alkyne analogue for the Eschenmoser methenylation of carbonyl derivatives. In addition, a new bench-stable precatalyst for iron-catalyzed propargylic C-H functionalization is reported.

3.
Int J Pharm ; 657: 124126, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38626845

RESUMO

As the monotherapy of available analgesics is usually accompanied by serious side effects or limited efficacy in the management of chronic pain, multimodal analgesia is widely used to achieve improved benefit-to-risk ratios in clinic. Drug-drug salts are extensively researched to optimize the physicochemical properties of active pharmaceutical ingredients (APIs) and achieve clinical benefits compared with individual APIs or their combination. New drug-drug salt crystals metformin-ibuprofen (MET-IBU) and metformin-naproxen (MET-NAP) were prepared from metformin (MET) and two poorly water-soluble anti-inflammatory drugs (IBU and NAP) by the solvent evaporation method. The structures of these crystals were confirmed by single crystal and powder X-ray diffraction, Hirshfeld surface, Fourier transform infrared spectroscopy and thermal analysis. Both MET-IBU and MET-NAP showed significantly improved solubility and intrinsic dissolution rate than the pure IBU or NAP. The stability test indicated that MET-IBU and MET-NAP have excellent physical stability under stressing test (10 days) and accelerated conditions (3 months). Moreover, isobolographic analysis suggested that MET-IBU and MET-NAP exerted potent and synergistic antinociceptive effects in λ-Carrageenan-induced inflammatory pain in mice, and both of them had an advantage in rapid pain relief. These results demonstrated the potential of MET-IBU and MET-NAP to achieve synergistic antinociceptive effects by developing drug-drug salt crystals.

4.
J Am Chem Soc ; 146(14): 9920-9927, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38557104

RESUMO

Plastic recycling is critical for waste management and achieving a circular economy, but it entails difficult trade-offs between performance and recyclability. Here, we report a thermoset, poly(α-cyanocinnamate) (PCC), synthesized using Knoevenagel condensation between terephthalaldehyde (TPA) and a triarm cyanoacetate star, that tackles this difficulty by harnessing its intrinsically conjugated and dynamic chemical characteristics. PCCs exhibit extraordinary thermal and mechanical properties with a typical Tg of ∼178 °C, Young's modulus of 3.8 GPa, and tensile strength of 102 MPa, along with remarkable flexibility and dimensional and chemical stabilities. Furthermore, end-of-life PCCs can be selectively degraded and partially recycled back into one starting monomer TPA for a new production cycle or reprocessed through dynamic exchange aided by cyanoacetate chain-ends. This study lays the scientific groundwork for the design of robust and recyclable thermosets, with transformative potential in plastic engineering.

5.
J Chem Theory Comput ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38648670

RESUMO

pH-responsive nanoparticles are ideal vehicles for drug delivery and are widely used in cell imaging in targeted therapy of cancer, which usually has a weakly acidic microenvironment. In this work, we constructed a titratable molecular model for nanoparticles grafted with ligands of pH-sensitive carboxylic acids and investigated the interactions between the nanoparticles and the lipid bilayer in varying pH environments. We mainly examined the effect of the grafting density of the pH-sensitive ligands of the nanoparticles on the interactions of the nanoparticles with the lipid bilayer. The results show that the nanoparticles can penetrate the lipid bilayer only when the pH value is lower than a critical value, which can be readily modulated to the specific pH value of the tumor microenvironment by changing the ligand grafting density. This work provides some insights into modulating the interactions between the pH-sensitive nanoparticles and cellular membranes to realize targeted drug delivery to tumors based on their specific pH environment.

6.
Sci Total Environ ; 927: 172368, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38614346

RESUMO

BACKGROUND: Disinfection byproducts (DBPs) have been shown to impair thyroid function in experimental models. However, epidemiological evidence is scarce. METHODS: This study included 1190 women undergoing assisted reproductive technology (ART) treatment from the Tongji Reproductive and Environmental (TREE) cohort from December 2018 to August 2021. Serum thyrotropin (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) were measured as indicators of thyroid function. FT4/FT3 and TSH/FT4 ratios were calculated as markers of thyroid hormone homeostasis. Dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA), the two most abundant HAAs, in urine were detected to assess individual DBP exposures. RESULTS: After adjusting for relevant covariates, positive associations were observed between urinary TCAA concentrations and serum TSH and TSH/FT4 levels (e.g., percent change = 5.82 %, 95 % CI: 0.70 %, 11.21 % for TSH), whereas inverse associations were found for serum FT3 and FT4 (e.g., percent change = -1.29 %, 95 % CI: -2.49 %, -0.07 % for FT3). There also was a negative association between urinary DCAA concentration and serum FT4/FT3 (percent change = -2.49 %, 95 % CI: -4.71 %, -0.23 %). These associations were further confirmed in the restricted cubic spline and generalized additive models with linear or U-shaped dose-response relationships. CONCLUSION: Urinary HAAs were associated with altered thyroid hormone homeostasis among women undergoing ART treatment.


Assuntos
Glândula Tireoide , Humanos , Feminino , Adulto , Tiroxina/sangue , Tri-Iodotironina/sangue , Tireotropina/sangue , Hormônios Tireóideos/sangue , Testes de Função Tireóidea , Desinfetantes , Acetatos , China
7.
Sci Total Environ ; 927: 172185, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38575009

RESUMO

Phthalate exposure can adversely impact ovarian reserve, yet investigation on the influence of its alternative substance, the non-phthalate plasticizer diisononyl-cyclohexane-1,2-dicarboxylate (DINCH), on ovarian reserve is very sparce. We aimed to investigate the associations of phthalate and DINCH exposure as well as their combined mixture with ovarian reserve. This present study included 657 women seeking infertility care in Jiangsu, China (2015-2018). Urine samples during enrollment prior to infertility treatment were analyzed using high-performance liquid chromatography-isotope dilution tandem mass spectrometry (UPLC-MS/MS) to quantify 17 phthalate metabolites and 3 DINCH metabolites. Multivariate linear regression models, Poisson regression models and weighted quantile sum (WQS) regression were performed to access the associations of 17 urinary phthalate metabolites and 3 DINCH metabolites with ovarian reserve markers, including antral follicle count (AFC), anti-Mullerian hormone (AMH), and follicle-stimulating hormone (FSH). We found that the most conventional phthalates metabolites (DMP, DnBP, DiBP, DBP and DEHP) were inversely associated with AFC, and the DINCH metabolites were positively associated with serum FSH levels. The WQS index of phthalate and DINCH mixtures was inversely associated with AFC (% change = -8.56, 95 % CI: -12.63, -4.31) and positively associated with FSH levels (% change =7.71, 95 % CI: 0.21, 15.78). Our findings suggest that exposure to environmental levels of phthalate and DINCH mixtures is inversely associated with ovarian reserve.


Assuntos
Ácidos Cicloexanocarboxílicos , Reserva Ovariana , Ácidos Ftálicos , Feminino , Humanos , Reserva Ovariana/efeitos dos fármacos , Adulto , China , Ácidos Dicarboxílicos , Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais , Biomarcadores , Infertilidade Feminina
8.
Sci Adv ; 10(14): eadj7666, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38569041

RESUMO

Inflammation-associated fibroblasts (IAFs) are associated with progression and drug resistance of chronic inflammatory diseases such as inflammatory bowel disease (IBD), but their direct impact on epithelial cells is unknown. Here, we developed an in vitro model whereby human colon fibroblasts are induced by specific cytokines and recapitulate key features of IAFs in vivo. When cocultured with patient-derived colon organoids (colonoids), IAFs induced rapid colonoid expansion and barrier disruption due to swelling and rupture of individual epithelial cells. Colonoids cocultured with IAFs also show increased DNA damage, mitotic errors, and proliferation arrest. These IAF-induced epithelial defects are mediated by a paracrine pathway involving prostaglandin E2 and its receptor EP4, leading to protein kinase A -dependent activation of the cystic fibrosis transmembrane conductance regulator. EP4-specific chemical inhibitors effectively prevented IAF-induced colonoid swelling and restored normal proliferation and genome stability. These findings reveal a mechanism by which IAFs could promote and perpetuate IBD and suggest a therapeutic avenue to mitigate inflammation-associated epithelial injury.


Assuntos
Doenças Inflamatórias Intestinais , Prostaglandinas , Humanos , Epitélio/metabolismo , Inflamação , Doenças Inflamatórias Intestinais/etiologia , Doenças Inflamatórias Intestinais/metabolismo , Fibroblastos/metabolismo
9.
J Orthop Surg (Hong Kong) ; 32(1): 10225536241244825, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38607239

RESUMO

PURPOSE: This study aims to systematically review the efficacy and safety of total ankle replacement (TAR) and ankle fusion (AF) as treatment options for end-stage ankle arthritis. METHODS: A comprehensive literature search was conducted on data from multiple databases, including PubMed, The Cochrane Library, Construction and Building Materials, Embase, Web of Science, and Scopus for RCTs and prospective cohort studies comparing TAR and AF in patients with end-stage ankle arthritis from inception up to June, 2023. Our primary outcomes of interest included patients' clinical function scores and complications. We employed Review Manager 5.4 and Stata/MP 14.0 software for the meta-analysis. RESULTS: Our analysis incorporated 13 comparative studies, including 11 prospective studies, one pilot RCT, and one RCT. The pooled results revealed no significant difference in postoperative Short Form-36 scores between the TAR and AF groups (MD = -1.19, 95% CI: -3.89 to 1.50, p = .39). However, the postoperative Foot and Ankle Ability Measure scores in the AF group were significantly higher than in the TAR group (MD = 8.30, 95% CI: 1.01-15.60, p = .03). There was no significant difference in postoperative complication rates between the TAR and AF groups (RR = 0.95, 95% CI: 0.59 to 1.54, p = .85). CONCLUSION: Currently available evidence suggests no significant disparity in postoperative outcomes between TAR and AF. In the short term, TAR demonstrates better clinical scores than AF and lower complication rates. Conversely, in the long term, AF exhibits superior clinical scores and lower complication rates, although this difference is not statistically significant.


Assuntos
Artrite , Artroplastia de Substituição do Tornozelo , Humanos , Tornozelo , Estudos Prospectivos , Articulação do Tornozelo/cirurgia , Artrite/cirurgia
10.
World J Gastroenterol ; 30(9): 1121-1131, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38577194

RESUMO

BACKGROUND: Traditional esophagogastroduodenoscopy (EGD), an invasive examination method, can cause discomfort and pain in patients. In contrast, magnetically controlled capsule endoscopy (MCE), a noninvasive method, is being applied for the detection of stomach and small intestinal diseases, but its application in treating esophageal diseases is not widespread. AIM: To evaluate the safety and efficacy of detachable string MCE (ds-MCE) for the diagnosis of esophageal diseases. METHODS: Fifty patients who had been diagnosed with esophageal diseases were prospectively recruited for this clinical study and underwent ds-MCE and conventional EGD. The primary endpoints included the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of ds-MCE for patients with esophageal diseases. The secondary endpoints consisted of visualizing the esophageal and dentate lines, as well as the subjects' tolerance of the procedure. RESULTS: Using EGD as the gold standard, the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy of ds-MCE for esophageal disease detection were 85.71%, 86.21%, 81.82%, 89.29%, and 86%, respectively. ds-MCE was more comfortable and convenient than EGD was, with 80% of patients feeling that ds-MCE examination was very comfortable or comfortable and 50% of patients believing that detachable string v examination was very convenient. CONCLUSION: This study revealed that ds-MCE has the same diagnostic effects as traditional EGD for esophageal diseases and is more comfortable and convenient than EGD, providing a novel noninvasive method for treating esophageal diseases.


Assuntos
Endoscopia por Cápsula , Doenças do Esôfago , Humanos , Endoscopia por Cápsula/métodos , Estudos Prospectivos , Doenças do Esôfago/diagnóstico , Endoscopia do Sistema Digestório/métodos , Sensibilidade e Especificidade
11.
Nat Commun ; 15(1): 2129, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38459042

RESUMO

The development of advanced materials capable of autonomous self-healing and mechanical stimulus sensing in aquatic environments holds great promise for applications in underwater soft electronics, underwater robotics, and water-resistant human-machine interfaces. However, achieving superior autonomous self-healing properties and effective sensing simultaneously in an aquatic environment is rarely feasible. Here, we present an ultrafast underwater molecularly engineered self-healing piezo-ionic elastomer inspired by the cephalopod's suckers, which possess self-healing properties and mechanosensitive ion channels. Through strategic engineering of hydrophobic C-F groups, hydrolytic boronate ester bonds, and ions, the material achieves outstanding self-healing efficiencies, with speeds of 94.5% (9.1 µm/min) in air and 89.6% (13.3 µm/min) underwater, coupled with remarkable pressure sensitivity (18.1 kPa-1) for sensing performance. Furthermore, integration of this mechanosensitive device into an underwater submarine for signal transmission and light emitting diode modulation demonstrates its potential for underwater robotics and smarter human-machine interactions.

12.
Plant Physiol ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38466216

RESUMO

Soil (or plant) water deficit accelerates plant reproduction. However, the underpinning molecular mechanisms remain unknown. By modulating cell division/number, ABSCISIC ACID-INSENSITIVE 5 (ABI5), a key bZIP (basic (region) leucine zippers) transcription factor, regulates both seed development and abiotic stress responses. The KRP (KIP-RELATED PROTEIN) cyclin-dependent kinases (CDKs) play an essential role in controlling cell division, and SHOOT MERISTEMLESS (STM) plays a key role in the specification of flower meristem identity. Here, our findings show that abscisic acid (ABA) signaling and/or metabolism in adjust reproductive outputs (such as rosette leaf number and open flower number) under water-deficient conditions in Arabidopsis (Arabidopsis thaliana) plants. Reproductive outputs increased under water-sufficient conditions but decreased under water-deficient conditions in the ABA signaling/metabolism mutants abscisic acid2-1 (aba2-1), aba2-11, abscisic acid insensitive3-1 (abi3-1), abi4-1, abi5-7, and abi5-8. Further, under water-deficient conditions, ABA induced-ABI5 directly bound to the promoter of KRP1, which encodes a CDK that plays an essential role in controlling cell division, and this binding subsequently activated KRP1 expression. In turn, KRP1 physically interacted with SHOOT MERISTEMLESS (STM), which functions in the specification of flower meristem identity, promoting STM degradation. We further demonstrate that reproductive outputs are adjusted by the ABI5-KRP1-STM molecular module under water-deficient conditions. Together, our findings reveal the molecular mechanism by which ABA signaling and/or metabolism regulate reproductive development under water-deficient conditions. These findings provide insights that may help guide crop yield improvement under water deficiency.

13.
J Wound Care ; 33(3): 189-196, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38451787

RESUMO

OBJECTIVE: The reconstruction of complex soft tissue defects with exposure of bones and tendons represents an increasing challenge in wound care, especially in large extremity wounds. The aim of this study was to detect the clinical efficacy of combined use of negative pressure wound therapy (NPWT), artificial dermis (ADM), platelet-rich plasma (PRP) and split-thickness skin grafting (STSG) in the reconstruction of large traumatic extremity skin defects. METHOD: In this study, eight cases were treated with combined therapies for repairing complex extremity wounds and the results were reviewed retrospectively. After surgical debridement, all wounds received ADM, PRP and delayed STSG, which were all aided with NPWT. RESULTS: The patients consisted of five males and three females, with a mean age of 44 years. A total of six lower extremity wounds were located at the foot/ankle, with exposed tendon in five, bone exposure in three and both in two. Of the group, two patients had exposed tendon on arm/hand wounds. The size of wounds and ADM averaged 126cm2 and 42.3cm2, respectively. ADM was used to cover the exposed bone or tendon, the granulation and muscular tissue were covered with vacuum sealing drainage (VSD) directly, for NPWT. The survival rate of ADM averaged 98.9%. The average time for survival of ADM was 12.8 days and the mean uptake of autologous skin graft was 93.5%. Only one patient received repeated skin grafts. All patients achieved successful healing and reported no complications. The mean length of hospital stay was 36.1 days. CONCLUSION: Our study revealed that ADM in conjunction with NPWT, PRP and STSG could be used for repairing large traumatic extremity wounds. Wound closure was achieved without flaps, the aesthetic and functional outcomes were acceptable, and only one patient developed a 35% loss of skin graft. DECLARATION OF INTEREST: This work was supported by grants from the Natural Science Foundation of Hubei Province (grant no. 2020CFB464) and Youth Foundation of Wuhan Municipal Health Commission (grant no. WX20Q15). The authors have no conflicts of interest to declare.


Assuntos
Traumatismos do Braço , Tratamento de Ferimentos com Pressão Negativa , Plasma Rico em Plaquetas , Lesões dos Tecidos Moles , Masculino , Feminino , Adolescente , Humanos , Adulto , Estudos Retrospectivos , Tratamento de Ferimentos com Pressão Negativa/métodos , Cicatrização , Transplante de Pele/métodos , Resultado do Tratamento , Lesões dos Tecidos Moles/cirurgia , Derme
14.
BMC Med Imaging ; 24(1): 60, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38468226

RESUMO

BACKGROUND: Traditional process for clinically significant prostate cancer (csPCA) diagnosis relies on invasive biopsy and may bring pain and complications. Radiomic features of magnetic resonance imaging MRI and methylation of the PRKY promoter were found to be associated with prostate cancer. METHODS: Fifty-four Patients who underwent prostate biopsy or photoselective vaporization of the prostate (PVP) from 2022 to 2023 were selected for this study, and their clinical data, blood samples and MRI images were obtained before the operation. Methylation level of two PRKY promoter sites, cg05618150 and cg05163709, were tested through bisulfite sequencing PCR (BSP). The PI-RADS score of each patient was estimated and the region of interest (ROI) was delineated by 2 experienced radiologists. After being extracted by a plug-in of 3D-slicer, radiomic features were selected through LASSCO regression and t-test. Selected radiomic features, methylation levels and clinical data were used for model construction through the random forest (RF) algorithm, and the predictive efficiency was analyzed by the area under the receiver operation characteristic (ROC) curve (AUC). RESULTS: Methylation level of the site, cg05618150, was observed to be associated with prostate cancer, for which the AUC was 0.74. The AUC of T2WI in csPCA prediction was 0.84, which was higher than that of the apparent diffusion coefficient ADC (AUC = 0.81). The model combined with T2WI and clinical data reached an AUC of 0.94. The AUC of the T2WI-clinic-methylation-combined model was 0.97, which was greater than that of the model combined with the PI-RADS score, clinical data and PRKY promoter methylation levels (AUC = 0.86). CONCLUSIONS: The model combining with radiomic features, clinical data and PRKY promoter methylation levels based on machine learning had high predictive efficiency in csPCA diagnosis.


Assuntos
Imageamento por Ressonância Magnética , Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/genética , Neoplasias da Próstata/cirurgia , Imagem de Difusão por Ressonância Magnética , Aprendizado de Máquina , Metilação , Estudos Retrospectivos
15.
Sensors (Basel) ; 24(5)2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38474987

RESUMO

We present an innovative approach to mitigating brightness variations in the unmanned aerial vehicle (UAV)-based 3D reconstruction of tidal flat environments, emphasizing industrial applications. Our work focuses on enhancing the accuracy and efficiency of neural radiance fields (NeRF) for 3D scene synthesis. We introduce a novel luminance correction technique to address challenging illumination conditions, employing a convolutional neural network (CNN) for image enhancement in cases of overexposure and underexposure. Additionally, we propose a hash encoding method to optimize the spatial position encoding efficiency of NeRF. The efficacy of our method is validated using diverse datasets, including a custom tidal flat dataset and the Mip-NeRF 360 dataset, demonstrating superior performance across various lighting scenarios.

16.
Angew Chem Int Ed Engl ; : e202400955, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489506

RESUMO

Vitrimers represent an emerging class of polymeric materials that combine the desirable characteristics of both thermoplastics and thermosets achieved through the design of dynamic covalent bonds within the polymer networks. However, these materials are prone to creep due to the inherent instability of dynamic covalent bonds. Consequently, there are pressing demands for the development of robust and stable dynamic covalent chemistries. Here, we report a catalyst-free α-acetyl cinnamate/acetoacetate (α-AC/A) exchange reaction to develop vitrimers with remarkable creep resistance. Small-molecule model studies revealed that the α-AC/A exchange occurred at temperatures above 140 °C in bulk, whereas at 120 °C, this reaction was absent. For demonstration in the case of polymers, copolymers derived from common vinyl monomers were crosslinked with terephthalaldehyde to produce α-AC/A vitrimers with tunable thermal and mechanical performance. All resulting α-AC/A vitrimers exhibited high stability, especially in terms of creep resistance at 120 °C, while retaining commendable reprocessability when subjected to high temperatures. This work showcases the α-AC/A exchange reaction as a novel and robust dynamic covalent chemistry capable of imparting both reprocessability and high stability to cross-linked networks.

17.
ChemSusChem ; : e202400153, 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38436523

RESUMO

Aliphatic-aromatic copolyesters offer a promising solution to mitigate plastic pollution, but high content of aliphatic units (>40 %) often suffer from diminished comprehensive performances. Poly(butylene oxalate-co-furandicarboxylate) (PBOF) copolyesters were synthesized by precisely controlling the oxalic acid content from 10 % to 60 %. Compared with commercial PBAT, the barrier properties of PBOF for H2O and O2 increased by more than 6 and 26 times, respectively. The introduction of the oxalic acid units allowed the water contact angle to be reduced from 82.5° to 62.9°. Superior hydrophilicity gave PBOF an excellent degradation performance within a 35-day hydrolysis. Interestingly, PBO20F and PBO30F also displayed obvious decrease of molecular weight during hydrolysis, with elastic modulus >1 GPa and tensile strength between 35-54 MPa. PBOF achieved the highest hydrolysis rates among the reported PBF-based copolyesters. The hydrolytic mechanism was further explored based on Fukui function analysis and density functional theory (DFT) calculation. Noncovalent analysis indicated that the water molecules formed hydrogen bonding interaction with adjacent ester groups and thus improved the reactivity of carbonyl carbon. PBOF not only meet the requirements of the high-performance packaging market but can quickly degrade after the end of their usage cycles, providing a new choice for green and environmental protection.

18.
J Hand Surg Asian Pac Vol ; 29(2): 134-139, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38494164

RESUMO

Background: The most common types of wrist dislocation are trans-scaphoid lunate dislocation (TLD) and trans-scaphoid perilunate dislocation, in which the lunate and proximal scaphoid are dislocated through the midcarpal joint. There is another rare type of dislocation in which the proximal carpi are dislocated through the radiocarpal joint. The purpose of this study is to examine the clinical features of this type of dislocation. Methods: Six cases of the proximal carpal fracture dislocation via the radiocarpal joint were retrospectively reviewed. All patients underwent open reduction and internal fixation with the ligament reconstruction. A Mayo wrist score was assigned to each patient based on the assessment of pain, functional status, range of motion and grip strength at the last follow-up. Clinical subjective evaluation of function and pain was assessed using the patient-rated wrist evaluation (PRWE) method. Results: All patients were male and injured with a median age of 33.5 years. The median follow-up period was 10 months. There were three types of dislocations: Scaphoid fracture dislocation, TLD and scaphoid-lunate dislocation. All patients had satisfactory results with an average PRWE of 7.2 ± 4.7. The preoperative VAS was 6.7 ± 1.0 and the postoperative VAS was 0.7 ± 0.7 (p < 0.01). Postoperative grip strength accounted for 89.2% ± 9.8% of the contralateral side; the Mayo wrist score averaged 90.0 ± 6.5, with four patients obtaining excellent and two good results. Conclusions: Fracture dislocation of the proximal carpal bones through the radiocarpal joint is an independent type of wrist dislocation that tends to occur in young men with high-energy impact. The wrist is most often injured in a pronation hyperextension position. If treatment is timely and appropriate, the prognosis is quite good. Level of Evidence: Level IV (Therapeutic).


Assuntos
Fratura-Luxação , Fraturas Ósseas , Traumatismos da Mão , Luxações Articulares , Osso Escafoide , Traumatismos do Punho , Humanos , Masculino , Adulto , Feminino , Fraturas Ósseas/cirurgia , Estudos Retrospectivos , Osso Escafoide/cirurgia , Luxações Articulares/diagnóstico por imagem , Luxações Articulares/cirurgia , Traumatismos do Punho/diagnóstico por imagem , Traumatismos do Punho/cirurgia
19.
Transl Pediatr ; 13(2): 288-299, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38455747

RESUMO

Background: Inflammatory myofibroblastic tumors (IMTs) are a spectrum of tumors that range in morphology and biological behavior from benign, intermediate, to apparently malignant and epithelioid inflammatory myofibroblastic sarcoma (EIMS) is one of the malignant subtypes. This study tried to provide experience and new ideas for treating this rare disease. Methods: This study retrospectively analyzed and followed up 12 children with EIMS admitted to Beijing Children's Hospital, Baoding Children's Hospital, and Children's Hospital of Chongqing Medical University from August 2016 to May 2022. Results: Of the 12 children, 7 were male and 5 were female, with a median age of 74.50 [interquartile range (IQR), 61.50-90.00] months. Of these patients, eight had a single lesion and four had multiple lesions. The maximum diameter of the single tumor foci was 19.30 cm, the full meridian of the multiple tumor foci target lesions was 32.67 cm, and the median maximum tumor size was 11.99 (IQR, 7.80-15.70) cm. The site of disease was the abdominopelvic cavity in eight cases, the thoracic cavity in two cases, the maxillofacial region in one case, and the larynx in one case. The clinical manifestations were predominantly elevated body temperature (n=8). There was one case of ROS1 fusion mutation and nine cases of ALK fusion mutation. Of the 12 children, 6 were biopsied at the initial diagnosis and 6 were surgically treated. Follow-up treatment included preoperative neoadjuvant chemotherapy (n=4), peritoneal thermal perfusion therapy (n=2), targeted therapy (n=3), postoperative chemotherapy (n=5), and radiotherapy (n=3). The follow-up time was 14.50 (IQR, 10.50-31.50) months, with eight cases of tumor-free survival, two cases of death, and two cases of loss of follow-up. Conclusions: EIMS in children is extremely rare and clinically aggressive. The clinical presentation is nonspecific, and the initial diagnosis of the tumor is often large. Mutations in the ALK gene are common in EIMS. Surgery is the mainstay of EIMS treatment, and patients benefit from a multidisciplinary combination that includes targeted therapies, with long-term prognosis remaining subject to ongoing follow-up.

20.
Ultrason Sonochem ; 104: 106846, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38492554

RESUMO

This study explores the mitigation of cavitation damage in hydraulic engineering through air entrainment. The primary aim is to experimentally analyze the shock wave characteristics emitted by cavitation bubbles adjacent to air bubbles affixed to a tube nozzle. The schlieren optical system is utilized to visualize the shock wave, while a hydrophone measures its pressure. Experiments are conducted on cavitation bubbles induced by the spark-generated method in the vicinity of air bubbles, varying the dimensionless distances and sizes of the air bubbles. The results indicate that (1) The introduction of an air bubble noticeably changes the morphology, kinematic behavior, and shock wave features of the cavitation bubble. (2) Four distinct shock wave patterns are identified based on the quantity and shape of the shock wave, with variations in the cavitation bubble's collapsing behavior and shock wave characteristics across different patterns. (3) The dimensionless distance γ and size δ exert significant influence on the shock wave's quantity, pressure peak, shape, and energy. With γ decreases or δ increases, the shock wave quantity increases while the shock wave intensity decreases. This investigation of the interaction between cavitation bubbles and air bubbles is essential for elucidating the mechanism through which air entrainment mitigates cavitation damage.

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