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1.
Osteoporos Int ; 35(6): 1049-1059, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38459138

RESUMO

PURPOSE: This study aimed to apply a newly developed semi-automatic phantom-less QCT (PL-QCT) to measure proximal humerus trabecular bone density based on chest CT and verify its accuracy and precision. METHODS: Subcutaneous fat of the shoulder joint and trapezius muscle were used as calibration references for PL-QCT BMD measurement. A self-developed algorithm based on a convolution map was utilized in PL-QCT for semi-automatic BMD measurements. CT values of ROIs used in PL-QCT measurements were directly used for phantom-based quantitative computed tomography (PB-QCT) BMD assessment. The study included 376 proximal humerus for comparison between PB-QCT and PL-QCT. Two sports medicine doctors measured the proximal humerus with PB-QCT and PL-QCT without knowing each other's results. Among them, 100 proximal humerus were included in the inter-operative and intra-operative BMD measurements for evaluating the repeatability and reproducibility of PL-QCT and PB-QCT. RESULTS: A total of 188 patients with 376 shoulders were involved in this study. The consistency analysis indicated that the average bias between proximal humerus BMDs measured by PB-QCT and PL-QCT was 1.0 mg/cc (agreement range - 9.4 to 11.4; P > 0.05, no significant difference). Regression analysis between PB-QCT and PL-QCT indicated a good correlation (R-square is 0.9723). Short-term repeatability and reproducibility of proximal humerus BMDs measured by PB-QCT (CV: 5.10% and 3.41%) were slightly better than those of PL-QCT (CV: 6.17% and 5.64%). CONCLUSIONS: We evaluated the bone quality of the proximal humeral using chest CT through the semi-automatic PL-QCT system for the first time. Comparison between it and PB-QCT indicated that it could be a reliable shoulder BMD assessment tool with acceptable accuracy and precision. This study developed and verify a semi-automatic PL-QCT for assessment of proximal humeral bone density based on CT to assist in the assessment of proximal humeral osteoporosis and development of individualized treatment plans for shoulders.


Assuntos
Densidade Óssea , Osso Esponjoso , Úmero , Tomografia Computadorizada por Raios X , Humanos , Densidade Óssea/fisiologia , Masculino , Feminino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodos , Idoso , Reprodutibilidade dos Testes , Úmero/diagnóstico por imagem , Úmero/fisiologia , Osso Esponjoso/diagnóstico por imagem , Osso Esponjoso/fisiopatologia , Osso Esponjoso/fisiologia , Algoritmos , Imagens de Fantasmas , Adulto , Osteoporose/fisiopatologia , Osteoporose/diagnóstico por imagem , Idoso de 80 Anos ou mais
2.
Macromol Rapid Commun ; 43(10): e2200034, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35332623

RESUMO

Cancer remains a formidable global problem with a high mortality rate. There are many effective anti-cancer drugs in clinical use, among which paclitaxel (PTX) has good effects on non-small cell lung cancer, ovarian cancer, and breast cancer. However, when applied to the clinic, PTX still has many limitations, such as poor water solubility, drug resistance, and side effects on healthy tissues. A gold nanodots-paclitaxel-polylysine (AuNDs-PTX-PLL) core-shell nano-system of integrated diagnosis and treatment is constructed to achieve intelligent responsive drug delivery. On the one hand, the problem of poor water-solubility and drug resistance of PTX are solved. On the other hand, the nano-system has an excellent intelligent response effect. Drugs can only be released in the weakly acidic environment of the tumor, which reduces the damage and side effects to normal tissues. Moreover, the nano-system can be used for real-time tracking and auxiliary diagnosis for the tumor through the multi-mode imaging mode, such as fluorescence, photoacoustic, and computed tomography to achieve accurate visualization. The photothermal effect of AuNDs is beneficial to promote the release of drugs. The nano-system integrates multi-mode imaging, chemotherapy, intelligent drug release in tumor weakly acidic environment, and has excellent practical application prospects in tumor diagnosis and treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Nanopartículas , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Ouro , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Água
3.
Entropy (Basel) ; 24(7)2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35885075

RESUMO

Three different types of entropy weight methods (EWMs), i.e., EWM-A, EWM-B, and EWM-C, have been used by previous studies for integrating prediction models. These three methods use very different ideas on determining the weights of individual models for integration. To evaluate the performances of these three EWMs, this study applied them to developing integrated short-term traffic flow prediction models for signalized intersections. At first, two individual models, i.e., a k-nearest neighbors (KNN)-algorithm-based model and a neural-network-based model (Elman), were developed as individual models to be integrated using EWMs. These two models were selected because they have been widely used for traffic flow prediction and have been approved to be able to achieve good performance. After that, three integrated models were developed by using the three different types of EWMs. The performances of the three integrated models, as well as the individual KNN and Elman models, were compared. We found that the traffic flow predicted with the EWM-C model is the most accurate prediction for most of the days. Based on the model evaluation results, the advantages of using the EWM-C method were deliberated and the problems with the EWM-A and EWM-B methods were also discussed.

4.
Cereb Cortex ; 30(7): 3859-3871, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31989159

RESUMO

Excessive activation of N-methyl-D-aspartate receptors (NMDARs) and the resulting neuronal nitric oxide synthase (nNOS) activation plays a crucial role in the pathogenesis of traumatic brain injury (TBI). However, directly inhibiting NMDARs or nNOS produces adverse side effects because they play key physiological roles in the normal brain. Since interaction of nNOS-PSD95 is a key step in NMDAR-mediated excitotoxicity, we investigated whether disrupting nNOS-PSD95 interaction with ZL006, an inhibitor of nNOS-PSD95 interaction, attenuates NMDAR-mediated excitotoxicity. In cortical neuronal cultures, ZL006 treatment significantly reduced glutamate-induced neuronal death. In a mouse model of controlled cortical impact (CCI), administration of ZL006 (10 mg/kg, i.p.) at 30 min postinjury significantly inhibited nNOS-PSD95 interaction, reduced TUNEL- and phospho-p38-positive neurons in the motor cortex. ZL006 treatment also significantly reduced CCI-induced cortical expression of apoptotic markers active caspase-3, PARP-1, ratio of Bcl-2/Bax, and phosphorylated p38 MAPK (p-p38). Functionally, ZL006 treatment significantly improved neuroscores and sensorimotor performance, reduced somatosensory and motor deficits, reversed CCI-induced memory deficits, and attenuated cognitive impairment. Histologically, ZL006 treatment significantly reduced the brain lesion volume. These findings collectively suggest that blocking nNOS-PSD95 interaction represents an attractive strategy for ameliorating consequences of TBI and that its action is mediated via inhibiting neuronal apoptosis and p38 MAPK signaling.


Assuntos
Lesões Encefálicas Traumáticas/metabolismo , Córtex Cerebral/metabolismo , Cognição , Proteína 4 Homóloga a Disks-Large/genética , Neurônios/metabolismo , Óxido Nítrico Sintase Tipo I/genética , Recuperação de Função Fisiológica/genética , Ácidos Aminossalicílicos/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Benzilaminas/farmacologia , Lesões Encefálicas Traumáticas/fisiopatologia , Córtex Cerebral/citologia , Córtex Cerebral/lesões , Proteína 4 Homóloga a Disks-Large/metabolismo , Ácido Glutâmico/toxicidade , Camundongos , Teste do Labirinto Aquático de Morris , Neurônios/efeitos dos fármacos , Óxido Nítrico Sintase Tipo I/metabolismo , Cultura Primária de Células , Ratos , Teste de Desempenho do Rota-Rod
5.
BMC Musculoskelet Disord ; 22(1): 3, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33397336

RESUMO

BACKGROUND: Restoration of joint congruity is an important factor for the prevention of subsequent arthritis in patients with Bennett's fracture. Surgical treatment of Bennett's fracture is thus generally recommended for displaced intra-articular fractures to the proximal aspect of the thumb metacarpal. Fluoroscopic examination is used to evaluate the adequacy of closed reduction after pinning of Bennett's fracture. The purpose of this study was to determine the accuracy of fluoroscopy to determine the reduction of Bennett's fractures. METHODS: A model was created, to mimic a Bennett's fracture utilizing ten fresh-frozen cadaveric hands. An oblique cut was made in the proximal aspect of the thumb metacarpal using an oscillating saw. The small oblique fragment involved 1/4-1/3 of the joint surface was then shifted in position creating a step-off or gap at the fracture site. An anatomical reduction model, gap models (1 mm, 2 mm, 3 mm), and step-off models (1 mm, 2 mm, 3 mm) were created using percutaneous fixation with two 1.0 mm Kirschner wires for each cadaveric hand. Fluoroscopic assessment then took place and was reviewed by 2 attending hand surgeons blinded to the actual position. Their estimated fluoroscopic position was then compared to the actual displacement. RESULTS: The step-off and gap on fluoroscopic examination showed a significant difference compared to the step-off and gap from direct visualization. The frequency of underestimation for the 3 mm displacement models from the fluoroscopic examination was 60%. The frequency for overestimated was 9% for the models in which displacement was within 2 mm (0, 1, 2 mm). CONCLUSIONS: The assessment of articular gap and step-off using PA (postero-anterior), AP (antero-posterior), and lateral view of fluoroscopic examination is not accurate as compared to the examination by direct visualization. Surgeons need to be aware that PA, AP and lateral view of fluoroscopic examination alone may not be sufficient to judge the final position of a reduced Bennett's fracture. Other methods such as live fluoroscopy in multiple different planes, 3-dimensional fluoroscopy or arthroscopic examination should be considered.


Assuntos
Fraturas Ósseas , Luxações Articulares , Ossos Metacarpais , Fios Ortopédicos , Fluoroscopia , Fixação Interna de Fraturas , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Humanos , Ossos Metacarpais/diagnóstico por imagem , Ossos Metacarpais/cirurgia , Polegar/diagnóstico por imagem , Polegar/cirurgia
6.
BMC Surg ; 21(1): 30, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33413245

RESUMO

BACKGROUND: A hibernoma, also known as a brown fat tumor, is a rare benign soft tissue tumor, which originates from brown adipose tissue remaining in the fetus after the gestational period. It is often detected in adult men, presenting as a painless slow-growing mass. Hibernomas of the thigh have been reported; however, motor and sensory disorders caused by the tumors compressing the femoral nerve have not been reported. We report a case of a histopathologically proven hibernoma that induced femoral mononeuropathy. CASE PRESENTATION: A 26-year-old man was admitted to the hospital due to a mass, approximately 11.0 × 9.0 × 4.0 cm in size, that had developed 5 years ago in the anterolateral aspect of the proximal thigh. Furthermore, he had a history of hypoesthesia 1 month prior to his admission. He had signs and symptoms of both a motor and sensory disorder, involving the anterior aspect of the right thigh and the medial aspect of the calf, along the distribution of the femoral nerve. During surgery, the femoral nerve was found to be compressed by the giant tumor. The resultant symptoms probably caused the patient to seek medical care. Marginal resection of the mass was performed by careful dissection, and the branches of the femoral nerve were spared. Histopathology examination showed findings suggestive of a hibernoma. At the 4-month follow-up, no femoral nerve compression was evident, and local tumor recurrence or metastasis was not found. CONCLUSIONS: Asymptomatic hibernomas do not require treatment; however, in cases of hibernomas with apparent symptoms, complete marginal surgical excision at an early stage is a treatment option because it is associated with a low risk of postoperative tumor recurrence.


Assuntos
Nervo Femoral/cirurgia , Neuropatia Femoral/diagnóstico por imagem , Neuropatia Femoral/cirurgia , Lipoma/complicações , Lipoma/patologia , Adulto , Neuropatia Femoral/etiologia , Neuropatia Femoral/patologia , Humanos , Lipoma/diagnóstico , Lipoma/cirurgia , Imageamento por Ressonância Magnética , Masculino , Recidiva Local de Neoplasia , Coxa da Perna , Resultado do Tratamento , Ultrassonografia Doppler em Cores
7.
BMC Surg ; 21(1): 52, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33482785

RESUMO

BACKGROUND: The treatment of defects on the volar surface of the finger has been scarcely reported, and its utility for digital resurfacing remains unclear. This study compared the outcomes of free medial plantar artery flap (MPAF) and dorsal digital-metacarpal flap (DDMF) in finger reconstruction. METHODS: This retrospective cohort study included 24 patients with soft-tissue defects on the volar surface of the finger from March 2014 to March 2017. The patients were divided into two groups: the MPAF group and the DDMF group. The operation time, complications, such as flap necrosis, graft loss, infection, paresthesia, and donor-site morbidity, as well as two-point discrimination (2-PD) were carefully recorded. The Michigan Hand Outcomes Questionnaire was used for conduct follow-up assessment. RESULTS: After more than 12 months of follow-up, the MPAF group had a longer operative time compared with DDMF group, but there was no significant difference between postoperative complications and 2-PD test result in patients without nerve injury. And in terms of overall function, Modified VSS score and 2-PD test (the patients with nerve injury), There were relatively obvious statistical differences, MPAF was superior to DDMF (p < 0.005). CONCLUSION: MPAF and DDMF are reliable for reconstruction of the volar surface of the finger; however, MPAF offers better functional outcomes and is associated with a lower incidence of postoperative complications.


Assuntos
Traumatismos dos Dedos , Retalhos de Tecido Biológico/irrigação sanguínea , Procedimentos de Cirurgia Plástica , Lesões dos Tecidos Moles , Adulto , Idoso , Desbridamento , Feminino , Traumatismos dos Dedos/cirurgia , Pé/transplante , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos , Lesões dos Tecidos Moles/cirurgia , Transplante de Tecidos/métodos , Resultado do Tratamento , Adulto Jovem
8.
Biochem Biophys Res Commun ; 508(4): 1126-1132, 2019 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-30553451

RESUMO

Brachial plexus root avulsion causes severe sequelae Treatments and prognosis face many problems, including inflammatory reaction, oxidative damage, and myelin related inhibitory effect. l-Theanine has anti-inflammatory, anti-oxidative, and neuroprotective effects. NEP1-40 competitively inhibits Nogo-66 receptor (NgR1) promotes axonal regeneration. Forty-eight Sprague-Dawley rats were randomly assigned into four groups to establish an animal model of brachial plexus root avulsion. Inflammation and oxidative damage were evaluated by spectrophotometry and motor function of the upper limbs was assessed via Terzis grooming test after modeling. Immunofluorescence and hematoxylin and eosin staining were utilized to determine the content of reactive oxygen species, activation of microglial cells, neuroprotection, and nerve regeneration. Compared with the control group, the L-Theanine + NEP1-40 group had significantly decreased myeloperoxidase, malondialdehyde, interleukin-6, reactive oxygen species, and microglial cells, significantly increased score on the Terzis grooming test, increased motor neuron content, and thickened muscle fibers, increased area, and appearance of large and clear motor endplate structures. The results of this study suggest that l-Theanine combined with NEP1-40significantly promoted nerve regeneration after brachial plexus root avulsion, and may be a potential treatment for promoting nerve regeneration. Possible mechanisms underlying these results are alleviation of oxidative damage and inflammatory responses in the injured area and antagonism of myelin inhibition.


Assuntos
Plexo Braquial/lesões , Plexo Braquial/fisiopatologia , Glutamatos/uso terapêutico , Regeneração Nervosa/efeitos dos fármacos , Fragmentos de Peptídeos/uso terapêutico , Radiculopatia/tratamento farmacológico , Radiculopatia/fisiopatologia , Recuperação de Função Fisiológica/efeitos dos fármacos , Animais , Células do Corno Anterior/efeitos dos fármacos , Células do Corno Anterior/metabolismo , Células do Corno Anterior/patologia , Plexo Braquial/efeitos dos fármacos , Plexo Braquial/patologia , Sobrevivência Celular/efeitos dos fármacos , Quimioterapia Combinada , Feminino , Glutamatos/farmacologia , Interleucina-6/metabolismo , Malondialdeído/metabolismo , Microglia/efeitos dos fármacos , Microglia/metabolismo , Placa Motora/efeitos dos fármacos , Placa Motora/fisiopatologia , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Fragmentos de Peptídeos/farmacologia , Peroxidase/metabolismo , Radiculopatia/patologia , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Medula Espinal/patologia , Medula Espinal/fisiopatologia
10.
Med Sci Monit ; 23: 1691-1700, 2017 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-28388595

RESUMO

BACKGROUND We explored the application of 3-dimensional (3D) printing technology in treating giant cell tumors (GCT) of the proximal tibia. A tibia block was designed and produced through 3D printing technology. We expected that this 3D-printed block would fill the bone defect after en-bloc resection. Importantly, the block, combined with a standard knee joint prosthesis, provided attachments for collateral ligaments of the knee, which can maintain knee stability. MATERIAL AND METHODS A computed tomography (CT) scan was taken of both knee joints in 4 patients with GCT of the proximal tibia. We developed a novel technique - the real-size 3D-printed proximal tibia model - to design preoperative treatment plans. Hence, with the application of 3D printing technology, a customized proximal tibia block could be designed for each patient individually, which fixed the bone defect, combined with standard knee prosthesis. RESULTS In all 4 cases, the 3D-printed block fitted the bone defect precisely. The motion range of the affected knee was 90 degrees on average, and the soft tissue balance and stability of the knee were good. After an average 7-month follow-up, the MSTS score was 19 on average. No sign of prosthesis fracture, loosening, or other relevant complications were detected. CONCLUSIONS This technique can be used to treat GCT of the proximal tibia when it is hard to achieve soft tissue balance after tumor resection. 3D printing technology simplified the design and manufacturing progress of custom-made orthopedic medical instruments. This new surgical technique could be much more widely applied because of 3D printing technology.


Assuntos
Artroplastia do Joelho/instrumentação , Neoplasias Ósseas/cirurgia , Tumor de Células Gigantes do Osso/cirurgia , Impressão Tridimensional , Desenho de Prótese/métodos , Tíbia/patologia , Tíbia/cirurgia , Adulto , Feminino , Fraturas Ósseas/cirurgia , Tumores de Células Gigantes/patologia , Tumores de Células Gigantes/cirurgia , Humanos , Articulação do Joelho/patologia , Prótese do Joelho , Masculino , Pessoa de Meia-Idade , Desenho de Prótese/instrumentação , Tomografia Computadorizada por Raios X , Resultado do Tratamento
11.
Med Sci Monit ; 22: 5124-5130, 2016 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-28017958

RESUMO

BACKGROUND Different extents and locations of acetabular cartilage defect have been supposed to be a major cause of undesirable outcomes of periacetabular osteotomy (PAO) in patients with developmental dysplasia of the hip (DDH). This study aimed to verify whether different locations of cartilage deficiency affect the biomechanical environment in a three-dimensional model utilizing finite element analysis (FEA). MATERIAL AND METHODS We developed 3 DDH models - DDH-1 (normal shape), DDH-2 (superior defect), and DDH-3 (anterosuperior defect) - by deforming from a normal hip model. We also developed 3 PAO models - PAO-1, PAO-2, and PAO-3 - through rotating osteotomized fragments. RESULTS The maximum von Mises stress in the normal hip was 13.06 MPa. In the DDH-1 model, the maximum value on the load-bearing area decreased from 15.49 MPa pre-PAO to 14.28 MPa post-PAO, while stresses in the DDH-2 and DDH-3 models were higher than in the DDH-1 model, both pre-PAO and post-PAO (30.46 MPa to 26.04 MPa for DDH-2; 33.89 MPa to 27.48 MPa for DDH-3). CONCLUSIONS This study shows that, both pre- and post-PAO, different types of cartilage deficiency affect the biomechanical environment. Furthermore, in dysplastic hips, obtaining accurate three-dimensional information about the acetabular cartilage can contribute substantially to PAO decision making.


Assuntos
Acetábulo/cirurgia , Cartilagem/patologia , Análise de Elementos Finitos , Luxação do Quadril/cirurgia , Osteotomia , Acetábulo/patologia , Cartilagem/cirurgia , Luxação do Quadril/patologia , Humanos , Masculino , Modelos Biológicos , Estresse Mecânico , Adulto Jovem
12.
Adv Healthc Mater ; 13(10): e2303460, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37957786

RESUMO

Self-pumping dressings become one of the optimal solutions for the controlled management of chronic diabetic wound exudate and wound healing. However, present self-pumping dressings are not only prone to breakage of the loose hydrophobic layer but also have cumbersome and complicated preparation steps, which hinder the application of self-pumping dressings in diabetic wound treatment. Herein, a novel self-pumping structure of superabsorbent Janus dressing is designed to improve the strength of the hydrophobic layer and promote diabetic wound healing. The Janus dressing consists of a hydrophobic layer with a drainage agent (drainage layer) and a fluffy 3D nanofiber cotton (absorbent layer). Regardless of the thickness of the drainage layer, the drainage agent in the drainage layer provides the fluid to penetrate the drainage layer to the absorbent layer for unidirectional fluid draining. In design proof, the superabsorbent Janus dressing provides unidirectional drainage of inflammatory exudate and regulation of macrophage polarization, resulting in faster diabetic wound healing than single-layer dressings. Thus, the Janus dressing demonstrates important clinical implications to offer a novel design and preparation strategy for accelerating diabetic wound healing.


Assuntos
Bandagens , Diabetes Mellitus , Humanos , Cicatrização , Exsudatos e Transudatos , Interações Hidrofóbicas e Hidrofílicas
13.
J Mater Chem B ; 12(7): 1706-1729, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38288779

RESUMO

Uncontrolled hemorrhage results in various complications and is currently the leading cause of death in the general population. Traditional hemostatic methods have drawbacks that may lead to ineffective hemostasis and even the risk of secondary injury. Therefore, there is an urgent need for more effective hemostatic techniques. Polymeric hemostatic materials, particularly hydrogels, are ideal due to their biocompatibility, flexibility, absorption, and versatility. Functional hemostatic hydrogels can enhance hemostasis by creating physical circumstances conducive to hemostasis or by directly interfering with the physiological processes of hemostasis. The procoagulant principles include increasing the concentration of localized hemostatic substances or establishing a physical barrier at the physical level and intervention in blood cells or the coagulation cascade at the physiological level. Moreover, synergistic hemostasis can combine these functions. However, some hydrogels are ineffective in promoting hemostasis or have a limited application scope. These defects have impeded the advancement of hemostatic hydrogels. To provide inspiration and resources for new designs, this review provides an overview of the procoagulant principles of hemostatic hydrogels. We also discuss the challenges in developing effective hemostatic hydrogels and provide viewpoints.


Assuntos
Hemostáticos , Humanos , Hemostáticos/farmacologia , Hidrogéis/farmacologia , Hemostasia , Coagulação Sanguínea , Hemorragia/tratamento farmacológico , Hemorragia/prevenção & controle
14.
Int J Nanomedicine ; 19: 1539-1556, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38406603

RESUMO

Purpose: Persistent Infections and inflammation are associated with impaired wound healing in diabetic patients. There is a pressing demand for innovative antimicrobial strategies to address infections arising from antibiotic-resistant bacteria. Polymer-modified gold nanoparticles (AuNPs) show broad-spectrum antibacterial properties and significant biocompatibility. This study investigated the antibacterial and wound healing efficacy of hydrogel dressings conjugated with chitosan-AuNPs in diabetic model rats. Methods: Chitosan (CS)-functionalized gold nanoparticles (CS-AuNPs) were incorporated into hydrogel dressings (Gel/CS-AuNPs), which were formulated through the chemical cross-linking of gelatin with sodium alginate (SA). The basic characteristics of Gel/CS-AuNPs were analyzed by TEM, SEM, XRD, and UV-visible spectra. Rheological, swelling, degradation, and adhesive properties of Gel/CS-AuNPs were also determined. In vitro anti-bactericidal effects of the Gel/CS-AuNPs were analyzed with E. coli, S. aureus, and MRSA. In vitro biocompatibility of the Gel/CS-AuNPs was evaluated using NIH3T3 cells. The in vivo antibacterial and wound healing efficacy of the Gel/CS-AuNPs was analyzed in the diabetic wound model rats. Histological and immunofluorescence staining were performed to determine the status of angiogenesis, epithelization, inflammation response, and collagen deposition. Results: Gel/CS-AuNPs demonstrated significant high biodegradability, water absorption bactericidal, and biocompatibility, and slight adhesiveness. Gel/CS-AuNPs exhibited pronounced antibacterial efficacy against gram-negative, gram-positive, and MRSA in a CS-AuNPs-dose-dependent manner. In the diabetic wound model rats, Gel/CS-AuNPs effectively killed MRSA, reduced inflammation, and promoted angiogenesis and collagen deposition and remodeling at the wound site. As a result, Gel/CS-AuNPs expedited the recovery process for infected diabetic wounds. Among the hydrogels with different CS-AuNPs concentrations, Gel/CS-Au25 with 25% CS-AuNPs showed the best bactericidal and wound healing performance. Conclusion: Gel/CS-AuNPs significantly improve the healing of MRSA-infected diabetic wounds in the rat model. Therefore, Gel/CS-AuNPs show great promise for the treatment of diabetic infection wound healing.


Assuntos
Quitosana , Diabetes Mellitus , Nanopartículas Metálicas , Humanos , Camundongos , Ratos , Animais , Antibacterianos/farmacologia , Antibacterianos/química , Quitosana/química , Ouro/química , Staphylococcus aureus/metabolismo , Hidrogéis/química , Escherichia coli , Células NIH 3T3 , Nanopartículas Metálicas/química , Cicatrização , Colágeno/metabolismo , Bactérias/metabolismo , Inflamação
15.
Gene ; 855: 147124, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36539045

RESUMO

The R2R3-MYB transcription factors are widely involved in the regulation of plant growth, biotic and abiotic stress responses. Meanwhile, seed germination, which is stimulated by internal and external environments, is a critical stage in the plant life cycle. However, the identification, characterization, and expression profiling of the Populus euphratica R2R3-MYB family in drought response during seed germination have been unknown. Our study attempted to identify and characterize the R2R3-MYB genes in P. euphratica (PeR2R3-MYBs) and explore how R2R3-MYBs trigger the drought and abscisic acid (ABA) response mechanism in its seedlings. Based on the analysis of comparative genomics, 174 PeR2R3-MYBs were identified and expanded driven by whole genome duplication or segment duplication events. The analysis of Ka/Ks ratios showed that, in contrast to most PeR2R3-MYBs, the other PeR2R3-MYBs were subjected to positive selection in P. euphratica. Further, the expression data of PeR2R3-MYBs under drought stress and ABA treatment, together with available functional data for Arabidopsis thaliana MYB genes, supported the hypothesis that PeR2R3-MYBs involved in response to drought are dependent or independent on ABA signaling pathway during seed germination, especially PeR2R3-MYBs with MYB binding sites (MBS) cis-element and/or tandem duplication. This study is the first report on the genome-wide analysis of PeR2R3-MYBs, as well as the other two Salicaceae species. The duplication events and differential expressions of PeR2R3-MYBs play important roles in enhancing the adaptation to drought desert environment. Our results provide a reference for prospective functional studies of R2R3-MYBs of poplars and lay the foundation for new breeding strategies to improve the drought tolerance of P. euphratica.


Assuntos
Arabidopsis , Populus , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Populus/genética , Populus/metabolismo , Genes myb , Proteínas de Plantas/metabolismo , Secas , Estudos Prospectivos , Melhoramento Vegetal , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Filogenia
16.
Biosens Bioelectron ; 235: 115386, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37187060

RESUMO

Diabetic wounds are chronically hard-healing wounds. Bacterial infection, persistent inflammation and impaired angiogenesis are key factors affecting diabetic wound healing. Herein, inspired by pomegranate, Au/Ag nanodots (Au/AgNDs) with fluorescent and photothermal properties were adopted as the pomegranate-like core, and the polyvinyl alcohol hydrogel as the pomegranate-like shell to obtain the multifunctional nanocomposite wound dressing for promoting diabetic wounds healing and real-time self-monitoring the dressing state. On the one hand, the antibacterial and photothermal therapy synergistic strategy based on the nanocomposite has an excellent treatment effect on diabetic wounds by highly antibacterial, anti-inflammation, accelerating collagen deposition and angiogenesis. On the other hand, the nanocomposite can be used as "smart messenger" to determine the appropriate time for dressing replacement. With the release of Au/AgNDs from the nanocomposite, the photothermal performance and antibacterial activity of the wound dressing were reduced, and the fluorescence intensity decreased. The change of fluorescence intensity can be visualized by the naked eye, which guides the appropriate time for dressing replacement, and avoids secondary wound damage caused by frequent and blind dressing replacement. This work provides an effective strategy for the treatment of diabetic wounds and intelligent self-monitoring of the state of dressings in clinical practice.


Assuntos
Técnicas Biossensoriais , Diabetes Mellitus , Nanocompostos , Bandagens , Cicatrização , Antibacterianos , Diabetes Mellitus/terapia
17.
Biomater Adv ; 149: 213394, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37001309

RESUMO

Infection prevention and bone-implant integration remain major clinical challenges. Silver nanoparticle (AgNPs) bone-implant coatings have received extensive attention. Balancing the toxicity and antibacterial properties of AgNP coatings has become a significant problem. In this study, inspired by the structure of the ant-nest, a polyetherimide (PEI) coating with ant-nest structure was prepared, aiming to realize the structural modification of the AgNPs coating. AgNPs were loaded in the inner porous area of the PEI ant-nest coating, avoiding direct contact between AgNPs and cells. The nanopores on the surface of the coating ensured the orderly release of silver ions. SEM, FTIR, XPS, and XRD experiments confirmed that the PEI ant-nest coating was successfully prepared. Interestingly, in the PEI ant-nest coating, Ag+ showed a steady increase in the release trend within 28 days, and there was no early burst release phenomenon. In -vivo experiments showed a good control effect for local infection. In order to improve the osteogenic properties of the materials, 45S5 bioactive glasses (BG) were loaded to achieve further osseointegration. In general, this natural ant-nest-inspired surface modification coating for orthopedic prostheses provides a new strategy for balancing the antibacterial and toxic effects of AgNP coatings.


Assuntos
Formigas , Membros Artificiais , Nanopartículas Metálicas , Animais , Prata/farmacologia , Biomimética , Osseointegração , Antibacterianos/farmacologia
18.
Front Cell Infect Microbiol ; 13: 1142029, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37033476

RESUMO

Fungal diseases have posed a great challenge to global health, but have fewer solutions compared to bacterial and viral infections. Development and application of new treatment modalities for fungi are limited by their inherent essential properties as eukaryotes. The microorganism identification and drug sensitivity analyze are limited by their proliferation rates. Moreover, there are currently no vaccines for prevention. Polymer science and related interdisciplinary technologies have revolutionized the field of fungal disease management. To date, numerous advanced polymer-based systems have been developed for management of fungal diseases, including prevention, diagnosis, treatment and monitoring. In this review, we provide an overview of current needs and advances in polymer-based strategies against fungal diseases. We high light various treatment modalities. Delivery systems of antifungal drugs, systems based on polymers' innate antifungal activities, and photodynamic therapies each follow their own mechanisms and unique design clues. We also discuss various prevention strategies including immunization and antifungal medical devices, and further describe point-of-care testing platforms as futuristic diagnostic and monitoring tools. The broad application of polymer-based strategies for both public and personal health management is prospected and integrated systems have become a promising direction. However, there is a gap between experimental studies and clinical translation. In future, well-designed in vivo trials should be conducted to reveal the underlying mechanisms and explore the efficacy as well as biosafety of polymer-based products.


Assuntos
Antifúngicos , Micoses , Humanos , Antifúngicos/uso terapêutico , Polímeros/uso terapêutico , Micoses/diagnóstico , Micoses/tratamento farmacológico , Micoses/prevenção & controle , Fungos
19.
Mater Today Bio ; 19: 100592, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36936399

RESUMO

Although the past decade has witnessed unprecedented medical advances, achieving rapid and effective hemostasis remains challenging. Uncontrolled bleeding and wound infections continue to plague healthcare providers, increasing the risk of death. Various types of hemostatic materials are nowadays used during clinical practice but have many limitations, including poor biocompatibility, toxicity and biodegradability. Recently, there has been a burgeoning interest in organisms that stick to objects or produce sticky substances. Indeed, applying biological adhesion properties to hemostatic materials remains an interesting approach. This paper reviews the biological behavior, bionics, and mechanisms related to hemostasis. Furthermore, this paper covers the benefits, challenges and prospects of biomimetic hemostatic materials.

20.
Mater Today Bio ; 23: 100834, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38024841

RESUMO

Achieving precision treatment in bone tissue engineering (BTE) remains a challenge. Photothermal therapy (PTT), as a form of precision therapy, has been extensively investigated for its safety and efficacy. It has demonstrated significant potential in the treatment of orthopedic diseases such as bone tumors, postoperative infections and osteoarthritis. However, the high temperatures associated with PTT can lead to certain limitations and drawbacks. In recent years, researchers have explored the use of biomaterials for mild photothermal therapy (MPT), which offers a promising approach for addressing these limitations. This review provides a comprehensive overview of the mechanisms underlying MPT and presents a compilation of photothermal agents and their utilization strategies for bone tissue repair. Additionally, the paper discusses the future prospects of MPT-assisted bone tissue regeneration, aiming to provide insights and recommendations for optimizing material design in this field.

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