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1.
Nanomicro Lett ; 16(1): 234, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954048

RESUMO

The impedance matching of absorbers is a vital factor affecting their microwave absorption (MA) properties. In this work, we controllably synthesized Material of Institute Lavoisier 88C (MIL-88C) with varying aspect ratios (AR) as a precursor by regulating oil bath conditions, followed by one-step thermal decomposition to obtain carbon-coated iron-based composites. Modifying the precursor MIL-88C (Fe) preparation conditions, such as the molar ratio between metal ions and organic ligands (M/O), oil bath temperature, and oil bath time, influenced the phases, graphitization degree, and AR of the derivatives, enabling low filler loading, achieving well-matched impedance, and ensuring outstanding MA properties. The MOF-derivatives 2 (MD2)/polyvinylidene Difluoride (PVDF), MD3/PVDF, and MD4/PVDF absorbers all exhibited excellent MA properties with optimal filler loadings below 20 wt% and as low as 5 wt%. The MD2/PVDF (5 wt%) achieved a maximum effective absorption bandwidth (EAB) of 5.52 GHz (1.90 mm). The MD3/PVDF (10 wt%) possessed a minimum reflection loss (RLmin) value of - 67.4 at 12.56 GHz (2.13 mm). A symmetric gradient honeycomb structure (SGHS) was constructed utilizing the high-frequency structure simulator (HFSS) to further extend the EAB, achieving an EAB of 14.6 GHz and a RLmin of - 59.0 dB. This research offers a viable inspiration to creating structures or materials with high-efficiency MA properties.

2.
Biomater Adv ; 163: 213958, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39053385

RESUMO

Irregular bone defects caused by trauma and bone diseases provide a complex implant environment for surgery. Traditional implants often fail to integrate well with the surrounding bone defect interface, therefore, developing an artificial bone scaffold that can adapt to irregular bone defect boundaries is of significant importance for bone defect repair. This study successfully utilized a shape memory ternary copolymer polylactic acid-trimethylene carbonate-hydroxyacetic acid (PLLA-TMC-GA) and dopamine-modified nano-hydroxyapatite (PHA) composite to construct a temperature-responsive bone repair scaffold (PTG/PHA), thereby enhancing the interface compatibility between the implant and the surrounding environment. The addition of PHA has effectively improved the hydrophilicity of the stent and significantly increased its mechanical strength. Furthermore, the Sodium alginate (SA) hydrogel loaded with Icariin (Ica) coated on the stent surface promotes the growth and differentiation of bone cells through the drug-scaffold synergistic effect. Both in vivo and in vitro experiments have shown that the synergistic effect of the composite stent with Icariin significantly enhances the repair of bone defects. This study provides a promising tissue engineering method for the repair of irregular bone defects.


Assuntos
Regeneração Óssea , Durapatita , Microesferas , Engenharia Tecidual , Alicerces Teciduais , Regeneração Óssea/efeitos dos fármacos , Alicerces Teciduais/química , Animais , Durapatita/química , Durapatita/farmacologia , Engenharia Tecidual/métodos , Flavonoides/farmacologia , Flavonoides/química , Alginatos/química , Alginatos/farmacologia , Poliésteres/química , Osteogênese/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Hidrogéis/química , Hidrogéis/farmacologia , Humanos
3.
Small ; : e2403681, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38804867

RESUMO

Infected bone defects are one of the most challenging problems in the treatment of bone defects due to the high antibiotic failure rate and the lack of ideal bone grafts. In this paper, inspired by clinical bone cement filling treatment, α-c phosphate (α-TCP) with self-curing properties is composited with ß-tricalcium phosphate (ß-TCP) and constructed a bionic cancellous bone scaffolding system α/ß-tricalcium phosphate (α/ß-TCP) by low-temperature 3D printing, and gelatin is preserved inside the scaffolds as an organic phase, and later loaded with a metal-polyphenol network structure of tea polyphenol-magnesium (TP-Mg) nanoparticles. The scaffolds mimic the structure and components of cancellous bone with high mechanical strength (>100 MPa) based on α-TCP self-curing properties through low-temperature 3D printing. Meanwhile, the scaffolds loaded with TP-Mg exhibit significant inhibition of Staphylococcus aureus (S.aureus) and promote the transition of macrophages from M1 pro-inflammatory to M2 anti-inflammatory phenotype. In addition, the composite scaffold also exhibits excellent bone-enhancing effects based on the synergistic effect of Mg2+ and Ca2+. In this study, a multifunctional ceramic scaffold (α/ß-TCP@TP-Mg) that integrates anti-inflammatory, antibacterial, and osteoinduction is constructed, which promotes late bone regenerative healing while modulating the early microenvironment of infected bone defects, has a promising application in the treatment of infected bone defects.

4.
Anal Chim Acta ; 1305: 342588, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38677842

RESUMO

BACKGROUND: Sulfur dioxide (SO2) is a significant gas signaling molecule in organisms, and viscosity is a crucial parameter of the cellular microenvironment. They are both involved in regulating many physiological processes in the human body. However, abnormalities in SO2 and viscosity levels are associated with various diseases, such as cardiovascular disease, lung cancer, respiratory diseases, neurological disorders, diabetes and Alzheimer's disease. Hence, it is essential to explore novel and efficient fluorescent probes for simultaneously monitoring SO2 and viscosity in organisms. RESULTS: We selected quinolinium salt with good stability, high fluorescence intensity, good solubility and low cytotoxicity as the fluorophore and developed a highly sensitive ratiometric probe QQD to identify SO2 and viscosity changes based on Förster resonance energy transfer/twisted intramolecular charge transfer (FRET/TICT) mechanism. Excitingly, compared with other probes for SO2 detection, QQD not only identified HSO3-/SO32- with a large Stokes shift (218 nm), low detection limit (1.87 µM), good selectivity, high energy transfer efficiency (92 %) and wide recognition range (1.87-200 µM), but also identified viscosity with a 26-fold fluorescence enhancement and good linearity. Crucially, QQD was applied to detect HSO3-/SO32- and viscosity in actual water and food samples. In addition, QQD had low toxicity and good photostability for imaging HSO3-/SO32- and viscosity in cells. These results confirmed the feasibility and reliability of QQD for HSO3-/SO32- and viscosity imaging and environmental detection. SIGNIFICANCE: We reported a unique ratiometric probe QQD for detecting HSO3-/SO32- and viscosity based on the quinolinium skeleton. In addition to detecting HSO3-/SO32- and viscosity change in actual water and food samples, QQD could also monitor the variations of HSO3-/SO32- and viscosity in cells, which provided an experimental basis for further exploration of the role of SO2 derivatives and viscosity in biological systems.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Viscosidade , Humanos , Dióxido de Enxofre/análise , Sulfitos/análise , Sulfitos/química , Limite de Detecção , Compostos de Quinolínio/química
5.
Rev Environ Health ; 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38452364

RESUMO

Humans are ubiquitously exposed to environmental endocrine disrupting chemicals such as phthalates. Phthalates can migrate out of products and enter the human body through ingestion, inhalation, or dermal application, can have potential estrogenic/antiestrogenic and/or androgenic/antiandrogenic activity, and are involved in many diseases. As a female reproductive organ that is regulated by hormones such as estrogen, progesterone and androgen, the uterus can develop several disorders such as leiomyoma, endometriosis and abnormal bleeding. In this review, we summarize the hormone-like activities of phthalates, in vitro studies of endometrial cells exposed to phthalates, epigenetic modifications in the uterus induced by phthalate exposure, and associations between phthalate exposure and uterine disorders such as leiomyoma and endometriosis. Moreover, we also discuss the current research gaps in understanding the relationship between phthalate exposure and uterine disorders.

6.
BMJ Open ; 14(1): e081736, 2024 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-38233053

RESUMO

OBJECTIVE: To evaluate the hospitalised patients with uterine fibroids (UFs) and describe treatment patterns in hospital-treated patients in central China from 2018 to 2021. DESIGN: A retrospective analysis. SETTING: The gynaecology departments of class A and class B secondary and tertiary hospitals in Hubei Province, China. PARTICIPANTS: 101 008 patients diagnosed with UFs from 1 January 2018 to 31 December 2021. RESULTS: The hospitalised patients with UFs increased with age, reaching a peak at ages 45-49 years and then gradually decreasing. Among these patients, 19.05% had anaemia symptoms. Women aged 25-29 years were more likely to be treated with laparoscopic myomectomy (62.22%), while women aged 20-24 years tend to choose open myomectomy (34.58%). Women over age 45 years who had entered perimenopause tended to be treated with laparoscopic hysterectomy (64.85% for those aged 65-69 years). Patients with fibroid with moderate-to-severe anaemia mostly chose hysterectomy. As a whole, the proportion of patients who chose laparoscopic hysterectomy was similar to that of patients who chose laparoscopic myomectomy (31.38% vs 31.14%). Only 2.08% of UFs were treated with high-frequency MRI-guided focused ultrasound surgery (MRgFUS). The number of patients who choose laparoscopic surgery or MRgFUS treatment was increasing year by year. After stratifying by hospital grade, we found that women treated at class A tertiary hospitals were more likely to have laparoscopic than open surgery (66.12% vs 31.26%). At class B secondary hospitals, 61.9% of the patients underwent myomectomy. By contrast, hysterectomy was used to treat the majority of patients at class A secondary hospitals and class B tertiary hospitals (57.79% and 57.57%, respectively). Use of MRgFUS was mainly concentrated within class A tertiary hospitals. CONCLUSION: UFs affect mainly women in childbearing period. Most patients chose to receive treatment at class A tertiary hospitals, among which laparoscopic myomectomy was the mainstream surgical method for patients in Hubei Province. TRIAL REGISTRATION NUMBER: NCT05840042.


Assuntos
Anemia , Leiomioma , Neoplasias Uterinas , Humanos , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias Uterinas/cirurgia , Leiomioma/cirurgia , Histerectomia , Hospitais , Anemia/etiologia , Resultado do Tratamento
7.
Front Bioeng Biotechnol ; 11: 1259696, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37662437

RESUMO

The clinical challenge of bone defects in the craniomaxillofacial region, which can lead to significant physiological dysfunction and psychological distress, persists due to the complex and unique anatomy of craniomaxillofacial bones. These critical-sized defects require the use of bone grafts or substitutes for effective reconstruction. However, current biomaterials and methods have specific limitations in meeting the clinical demands for structural reinforcement, mechanical support, exceptional biological performance, and aesthetically pleasing reconstruction of the facial structure. These drawbacks have led to a growing need for novel materials and technologies. The growing development of 3D printing can offer significant advantages to address these issues, as demonstrated by the fabrication of patient-specific bioactive constructs with controlled structural design for complex bone defects in medical applications using this technology. Poly (ether ether ketone) (PEEK), among a number of materials used, is gaining recognition as a feasible substitute for a customized structure that closely resembles natural bone. It has proven to be an excellent, conformable, and 3D-printable material with the potential to replace traditional autografts and titanium implants. However, its biological inertness poses certain limitations. Therefore, this review summarizes the distinctive features of craniomaxillofacial bones and current methods for bone reconstruction, and then focuses on the increasingly applied 3D printed PEEK constructs in this field and an update on the advanced modifications for improved mechanical properties, biological performance, and antibacterial capacity. Exploring the potential of 3D printed PEEK is expected to lead to more cost-effective, biocompatible, and personalized treatment of craniomaxillofacial bone defects in clinical applications.

8.
Int J Surg ; 109(6): 1688-1698, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37074037

RESUMO

BACKGROUND: Local excision as the main alternative for fertility-sparing surgery (FSS) has been widely used in patients with early-stage cervical cancer to achieve fertility preservation, but its safety and practicability are still questioned. Therefore, The authors evaluated the current application of local excision in early-stage cervical cancer with this population-based study and compared its efficacy with hysterectomy. MATERIALS AND METHODS: Women diagnosed with International Federation of Gynecology and Obstetrics (FIGO) stage I cervical cancer at childbearing age (18-49 years) recorded in the Surveillance, Epidemiology and End Results (SEER) database from 2000 to 2017 were included. Overall survival (OS) and disease-specific survival (DSS) rates were compared between local excision and hysterectomy. RESULTS: A total of 18 519 patients of reproductive age with cervical cancer were included, and 2268 deaths were observed. 17.0% of patients underwent FSS via local excision, and 70.1% underwent hysterectomy. Among patients younger than 39 years, OS and DSS of local excision were comparable to those of hysterectomy, whereas, in patients older than 40 years, OS and DSS of local excision were significantly worse than those of hysterectomy. In addition, OS and DSS of local excision were similar to hysterectomy in patients with stage IA cervical cancer, but OS and DSS were inferior to hysterectomy in patients with stage IB cervical cancer who underwent local excision. CONCLUSION: For patients without fertility requirements, hysterectomy remains the best therapeutic option. However, for patients under 40 years of age diagnosed with stage IA cervical cancer, FSS via local excision is a viable option that can achieve a well-balanced outcome between tumour control and fertility preservation.


Assuntos
Neoplasias do Colo do Útero , Gravidez , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Estudos de Coortes , Estadiamento de Neoplasias , Estudos Retrospectivos , Histerectomia/efeitos adversos
9.
Front Endocrinol (Lausanne) ; 13: 1094012, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36733809

RESUMO

Objective: This meta-analysis was performed to evaluate the effectiveness and safety of prophylactic central neck dissection (PCND) in patients with clinically node-negative (cN0) papillary thyroid carcinoma. Materials and methods: A meta-analysis of the literature was performed using the key words "papillary thyroid carcinomas" and "lymph node ecisions" for searches of electronic databases. Complications such as transient hypocalcemia, permanent hypocalcemia, transient and permanent hypoparathyroidism, transient and permanent vocal cord paralysis, transient recurrent and permanent recurrent laryngeal nerve injury, and local recurrence were pooled by meta-analysis. Stata17.0 was used to carry out the meta-analysis. Results: Data were extracted from 15 studies. In the present review, the group of patients who had total thyroidectomy (TT) with PCND had a lower local recurrence than the group with TT alone (OR 0.22, 95% CI 0.10-0.45, P = 0.000), whereas the incidence of permanent hypocalcemia (OR 4.24, 95% CI 1.05-17.22, P = 0.043) and transient hypoparathyroidism (OR 2.14, 95% CI 1.34-3.42, P =0.001) were higher. No significant differences were recorded in the incidence of other complications: transient hypocalcemia (OR 2.24, 95% CI 0.77-6.51, P = 0.138), permanent hypoparathyroidism (OR 1.70, 95% CI 0.89-3.27, P = 0.111), transient vocal cord paralysis (OR 1.48, 95% CI 0.78-2.83, P = 0.231), permanent vocal cord paralysis (OR 1.44, 95% CI 0.53-3.94, P = 0.477), transient recurrent laryngeal nerve injury (OR 1.47, 95% CI 0.93-2.32, P = 0.102) and permanent recurrent laryngeal nerve injury (OR 1.24, 95% CI 0.56-2.74, P = 0.587) between the two groups. Conclusion: Compared with TT alone, TT with PCND was more effective in reducing local recurrence without increasing the risk of recurrent laryngeal nerve, thyroid and vocal cord, except for hypocalcemia and transient hypoparathyroidism. Therefore, we believe that TT with PCND should be recommended for patients with cN0 PTC. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD4202 2355078.


Assuntos
Carcinoma Papilar , Hipocalcemia , Hipoparatireoidismo , Traumatismos do Nervo Laríngeo Recorrente , Neoplasias da Glândula Tireoide , Paralisia das Pregas Vocais , Humanos , Câncer Papilífero da Tireoide/cirurgia , Câncer Papilífero da Tireoide/complicações , Esvaziamento Cervical/efeitos adversos , Neoplasias da Glândula Tireoide/patologia , Paralisia das Pregas Vocais/epidemiologia , Paralisia das Pregas Vocais/etiologia , Paralisia das Pregas Vocais/prevenção & controle , Traumatismos do Nervo Laríngeo Recorrente/etiologia , Hipocalcemia/epidemiologia , Hipocalcemia/etiologia , Hipocalcemia/prevenção & controle , Carcinoma Papilar/patologia , Resultado do Tratamento , Hipoparatireoidismo/prevenção & controle , Hipoparatireoidismo/complicações
10.
Microb Cell Fact ; 20(1): 3, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33407464

RESUMO

BACKGROUND: Biosynthesis of L-tert-leucine (L-tle), a significant pharmaceutical intermediate, by a cofactor regeneration system friendly and efficiently is a worthful goal all the time. The cofactor regeneration system of leucine dehydrogenase (LeuDH) and glucose dehydrogenase (GDH) has showed great coupling catalytic efficiency in the synthesis of L-tle, however the multi-enzyme complex of GDH and LeuDH has never been constructed successfully. RESULTS: In this work, a novel fusion enzyme (GDH-R3-LeuDH) for the efficient biosynthesis of L-tle was constructed by the fusion of LeuDH and GDH mediated with a rigid peptide linker. Compared with the free enzymes, both the environmental tolerance and thermal stability of GDH-R3-LeuDH had a great improved since the fusion structure. The fusion structure also accelerated the cofactor regeneration rate and maintained the enzyme activity, so the productivity and yield of L-tle by GDH-R3-LeuDH was all enhanced by twofold. Finally, the space-time yield of L-tle catalyzing by GDH-R3-LeuDH whole cells could achieve 2136 g/L/day in a 200 mL scale system under the optimal catalysis conditions (pH 9.0, 30 °C, 0.4 mM of NAD+ and 500 mM of a substrate including trimethylpyruvic acid and glucose). CONCLUSIONS: It is the first report about the fusion of GDH and LeuDH as the multi-enzyme complex to synthesize L-tle and reach the highest space-time yield up to now. These results demonstrated the great potential of the GDH-R3-LeuDH fusion enzyme for the efficient biosynthesis of L-tle.


Assuntos
Bacillus cereus/enzimologia , Bacillus megaterium/enzimologia , Glucose 1-Desidrogenase/metabolismo , Leucina Desidrogenase/metabolismo , Leucina/biossíntese , Proteínas Recombinantes de Fusão/metabolismo , Glucose 1-Desidrogenase/química , Glucose 1-Desidrogenase/genética , Leucina Desidrogenase/química , Leucina Desidrogenase/genética , Conformação Proteica , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação
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