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1.
Arch Orthop Trauma Surg ; 144(4): 1523-1533, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38363322

RESUMO

OBJECTIVE: To systematically analyze the effectiveness of lumbar braces in patients after lumbar spine surgery. METHODS: The databases, including PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI), were searched to identify the randomized controlled trials (RCTs), case-series or case-control studies on the use of lumbar braces after lumbar spine surgery. The two authors independently assessed the quality of the included study and extracted the data. The statistical analysis was performed using Revman 5.4 software. RESULTS: 9 English papers and 1 Chinese paper were included in the present work, involving a total of 2646 patients (2181 in the experimental group and 465 in the control group). The differences in preoperative VAS, postoperative VAS, preoperative ODI, postoperative ODI, length of hospital stay, postoperative complications, and surgical comparison were not statistically significant (p > 0.05). However, postoperative surgical site infection incidence was lower in the lumbar brace group than those without lumbar brace (p < 0.05). CONCLUSION: Whether or not the use of lumbar braces after lumbar fixation has a negligible impact on clinical outcomes was studied. Subsequent studies could further demonstrate whether the use of lumbar braces after lumbar surgery could reduce the incidence of surgical site infections.


Assuntos
Braquetes , Vértebras Lombares , Humanos , Vértebras Lombares/cirurgia , Infecção da Ferida Cirúrgica/prevenção & controle , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/etiologia , Resultado do Tratamento
2.
Neural Plast ; 2022: 3593262, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35529454

RESUMO

Background: Various forms of theta-burst stimulation (TBS) such as intermittent TBS (iTBS) and continuous TBS (cTBS) have been introduced as novel facilitation/suppression schemes during repetitive transcranial magnetic stimulation (rTMS), demonstrating a better efficacy than conventional paradigms. Herein, we extended the rTMS-TBS schemes to electrical stimulation of high-definition montage (HD-TBS) and investigated its neural effects on the human brain. Methods: In a within-subject design, fifteen right-handed healthy adults randomly participated in 10 min and 2 mA HD-TBS sessions: unilateral (Uni)-iTBS, bilateral (Bi)-cTBS/iTBS, and sham stimulation over primary motor cortex regions. A 20-channel near-infrared spectroscopy (NIRS) system was covered on the bilateral prefrontal cortex (PFC), sensory motor cortex (SMC), and parietal lobe (PL) for observing cerebral hemodynamic responses in the resting-state and during fast finger-tapping tasks at pre-, during, and poststimulation. Interhemispheric correlation coefficient (IHCC) and wavelet phase coherence (WPCO) from resting-state NIRS and concentration of oxyhemoglobin during fast finger-tapping tasks were explored to reflect the symmetry between the two hemispheres and cortical activity, respectively. Results: The IHCC and WPCO of NIRS data in the SMC region under Bi-cTBS/iTBS showed relatively small values at low-frequency bands III (0.06-0.15 Hz) and IV (0.02-0.06), indicating a significant desynchronization in both time and frequency domains. In addition, the SMC activation induced by fast finger-tapping exercise was significantly greater during Uni-iTBS as well as during and post Bi-cTBS/iTBS sessions. Conclusions: It appears that a 10 min and 2 mA Bi-cTBS/iTBS applied over two hemispheres within the primary motor cortex region could effectively modulate the interhemispheric synchronization and cortical activation in the SMC of healthy subjects. Our study demonstrated that bilateral HD-TBS approaches is an effective noninvasive brain stimulation scheme which could be a novel therapeutic for inducing effects of neuromodulation on various neurological disorders caused by ischemic stroke or traumatic brain injuries.


Assuntos
Lobo Parietal , Estimulação Magnética Transcraniana , Adulto , Estimulação Elétrica , Potencial Evocado Motor/fisiologia , Voluntários Saudáveis , Humanos , Córtex Pré-Frontal/fisiologia , Ritmo Teta/fisiologia , Estimulação Magnética Transcraniana/métodos
3.
J Mater Sci Mater Med ; 30(4): 47, 2019 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-30980130

RESUMO

The objective of this study was to fabricate and characterize chitosan combined with different amounts of simvastatin-loaded nanoparticles and to investigate their potential for guided bone regeneration in vitro and in vivo. Different SIM-CSN formulations were combined into a chitosan scaffold (SIM-CSNs-S), and the morphology, simvastatin release profile, and effect on cell proliferation and differentiation were investigated. For in vivo experiments, ectopic osteogenesis and the critical-size cranial defect model in SD rats were chosen to evaluate bone regeneration potential. All three SIM-CSNs-S formulations had a porous structure and exhibited sustained simvastatin release. CSNs-S showed excellent degradation and biocompatibility characteristics. The 4 mg SIM-CSNs-S formulation stimulated higher BMSC ALP activity levels, demonstrated significantly earlier collagen enhancement, and led to faster bone regeneration than the other formulations. SIM-CSNs-S should have a significant effect on bone regeneration.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Quitosana/química , Regeneração Tecidual Guiada/métodos , Nanopartículas/química , Nanopartículas/metabolismo , Sinvastatina/farmacocinética , Alicerces Teciduais/química , Animais , Osso e Ossos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/metabolismo , Preparações de Ação Retardada , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Composição de Medicamentos , Masculino , Teste de Materiais , Microesferas , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Ratos , Ratos Sprague-Dawley , Sinvastatina/administração & dosagem , Propriedades de Superfície , Engenharia Tecidual/métodos
4.
J Mater Sci Mater Med ; 29(6): 84, 2018 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-29892913

RESUMO

This study aimed to develop of a rapid and effective method to occlude dentinal tubules using carboxymethyl chitosan and lysozyme (CMC/LYZ) nanogels with encapsulated amorphous calcium phosphate (ACP) based on the transformation of ACP to HAP. In this work, CMC/LYZ was used to stabilize ACP and form CMC/LYZ-ACP nanogels, and then the nanogel-encapsulated ACP was applied to exposed dentinal tubule surfaces. The morphology of the nanogels was examined by transmission electron microscopy (TEM). Distribution and quantity of elements in CMC/LYZ-ACP nanogels were determined by element mapping and energy dispersive X-Ray spectroscopy (EDX). Scanning electron microscopy (SEM) images, XRD measurements and nanoindentation were applied to check the efficacy of tubular occlusion. TEM revealed that CMC/LYZ-ACP nanogels were spherical dense gel particles with size approximately 50-500 nm. Element mapping and EDX indicated that C, N, O, Ca, P, and S in the microspheres are thoroughly represented. SEM images shows that the thickness of the coating layer was approximately 1-2 µm and the depth to which the mineralized substance enters the dentinal tubule was approximately 4-8 µm. XRD measurements and nanoindentation indicated that the occluding mineralized substance observed were similar to nature dentin. CMC can form spherical dense nanogels loaded with ACP under the participation of lysozyme. The CMC/LYZ-ACP nanogels could increase the dentinal tubule occluding effectiveness. These results indicated that finding and developing novel nanomaterials of CMC/LYZ-ACP would be an effective strategy for the treatment of dentin hypersensitivity.


Assuntos
Fosfatos de Cálcio/química , Quitosana/análogos & derivados , Sensibilidade da Dentina/terapia , Dente Molar/patologia , Muramidase/química , Nanopartículas/química , Adolescente , Adulto , Quitosana/química , Dentina/química , Ácido Edético/química , Módulo de Elasticidade , Géis , Humanos , Luz , Microscopia Eletrônica de Varredura , Microesferas , Tamanho da Partícula , Permeabilidade , Reprodutibilidade dos Testes , Espalhamento de Radiação , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Adulto Jovem
5.
Soft Matter ; 11(20): 4075-80, 2015 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-25909965

RESUMO

Novel gemini supra-amphiphiles, [Mim-4-Mim][DBS](2) and [Mim-4-Mim][DS](2), were facilely constructed. A slight variation of building blocks can effectively modulate the driving forces for the fabrication of gemini supra-amphiphiles, thus leading to the fine control of subsequent self-assemblies. [Mim-4-Mim][DS](2), constructed via electrostatic attraction, tends to form micelles and hexagonal liquid crystals. Rich lamellar structures, including unilamellar and multilamellar vesicles, planar bilayers, and lamellar liquid crystals can be formed by [Mim-4-Mim][DBS](2), which is constructed through electrostatic and π-π stacking interactions. With increasing temperatures, [Mim-4-Mim][DBS](2) exhibits interesting phase separation in the L(a) phase, behaving like common nonionic surfactants. The cross-linking between vesicles, where the "bola-type" [Mim-4-Mim](2+) cations act as the bridges, was found to promote the elongation of aggregates until the occurrence of phase separation.

6.
Orthopedics ; 47(4): e167-e173, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38690847

RESUMO

BACKGROUND: The objectives of this research were to establish an animal model of adjacent segment degeneration (ASD) bordering lumbar fusion and to investigate the expression of autophagy factors in nucleus pulposus cells of adjacent intervertebral disks. MATERIALS AND METHODS: Twenty-four adult New Zealand white rabbits were enrolled and divided into two groups: group A (n=12) and group B (n=12). Posterolateral fusion and fixation were performed after intervertebral disk degeneration occurred in group A, and the rabbits were monitored for 6 months. Group B was the control group and did not undergo fusion surgery. These rabbits were monitored for 6 months. Real-time quantitative polymerase chain reaction and immunohistochemistry were performed to detect the mRNA and protein expressions of PTEN-induced kinase 1 (PINK1), Parkin, ADAMTS-4, and MMP-3. An external database, the GEO database, was used to examine the expression of these genes and analyze them for differential expression. RESULTS: After lumbar fusion in rabbits, the animal model of ASD exhibited gradual degeneration of adjacent intervertebral disks over time. Group A displayed significantly higher mRNA and protein expressions of PINK1 and MMP-3 but lower expression of ADAMTS-4 compared with group B (P<.05). The results analyzed in the GEO database showed that the expression of PINK1 was higher in group A than in group B, while the expression of ADAMTS-4 was lower in group A than in group B. CONCLUSION: After posterolateral lumbar fusion in rabbits, the animal ASD model showed gradual deterioration of adjacent intervertebral disks with prolonged follow-up. The findings indicate the important role of autophagy in the apoptosis of nucleus pulposus cells in adjacent intervertebral disks. [Orthopedics. 2024;47(4):e167-e173.].


Assuntos
Autofagia , Modelos Animais de Doenças , Degeneração do Disco Intervertebral , Vértebras Lombares , Núcleo Pulposo , Fusão Vertebral , Animais , Coelhos , Núcleo Pulposo/metabolismo , Núcleo Pulposo/patologia , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/genética , Autofagia/fisiologia , Vértebras Lombares/cirurgia , Vértebras Lombares/patologia , Proteína ADAMTS4/metabolismo , Proteína ADAMTS4/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Proteínas Quinases/metabolismo , Proteínas Quinases/genética , Metaloproteinase 3 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/genética , Masculino
7.
J Colloid Interface Sci ; 664: 1002-1011, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38508028

RESUMO

Aqueous zinc-ion batteries (ZIBs) have attracted more and more attention due to their advantages of low cost, high safety and environmental protection. Unfortunately, the unsatisfactory capacity at high current density and long-term cycling performance of cathode materials hinder the development of ZIBs. Here, a novel Zn0.079V2O5·0.53H2O/graphene (ZVOH@rGO) hybrid aerogel composed of ultrathin Zn0.079V2O5·0.53H2O (ZVOH) nanoribbons and 3D continuous graphene conductive network was successfully prepared and used as cathode of ZIBs. Taking advantage of the synergistic effects associated with ion doping, morphology control and unique aerogel structure, the ZVOH@rGO electrode demonstrated ultrafast charge/discharge capability and remarkable cycling stability: A high reversible capacity of 286.7 mAh g-1 was achieved at a current density as large as 30 A g-1, and an impressive capacity retention ratio of 75.6 % was realized over 9800 ultra-long cycles at 12 A g-1. This work is of great significance for the synthesis modification of vanadium oxides and the development of high performance ultrafast charge-discharge ZIBs.

8.
Nanomicro Lett ; 16(1): 184, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684597

RESUMO

Rechargeable magnesium-metal batteries (RMMBs) are promising next-generation secondary batteries; however, their development is inhibited by the low capacity and short cycle lifespan of cathodes. Although various strategies have been devised to enhance the Mg2+ migration kinetics and structural stability of cathodes, they fail to improve electronic conductivity, rendering the cathodes incompatible with magnesium-metal anodes. Herein, we propose a dual-defect engineering strategy, namely, the incorporation of Mg2+ pre-intercalation defect (P-Mgd) and oxygen defect (Od), to simultaneously improve the Mg2+ migration kinetics, structural stability, and electronic conductivity of the cathodes of RMMBs. Using lamellar V2O5·nH2O as a demo cathode material, we prepare a cathode comprising Mg0.07V2O5·1.4H2O nanobelts composited with reduced graphene oxide (MVOH/rGO) with P-Mgd and Od. The Od enlarges interlayer spacing, accelerates Mg2+ migration kinetics, and prevents structural collapse, while the P-Mgd stabilizes the lamellar structure and increases electronic conductivity. Consequently, the MVOH/rGO cathode exhibits a high capacity of 197 mAh g-1, and the developed Mg foil//MVOH/rGO full cell demonstrates an incredible lifespan of 850 cycles at 0.1 A g-1, capable of powering a light-emitting diode. The proposed dual-defect engineering strategy provides new insights into developing high-durability, high-capacity cathodes, advancing the practical application of RMMBs, and other new secondary batteries.

9.
Digit Health ; 9: 20552076231194913, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37588157

RESUMO

Objective: Global trends, such as improving accessibility to healthcare services through the Internet, and the COVID-19 pandemic are among the driving factors in the adoption of digital health. This study hypothesized that digital solutions can reach and gather data from a large number of patients with trigeminal neuralgia (TN), a commonly misdiagnosed neuropathic facial pain syndrome, and quickly and fast-track their diagnosis by suggesting them to consult a neurologist. We developed an accessible digital screening tool based on patient symptoms and history to test this hypothesis and used social media advertisement to screen a general population for TN. Methods: The standard diagnostic criteria, International Classification of Orofacial Pain, for facial pain is digitized as a web-based questionnaire that allows easy access to the evaluation for patients with suspected TN symptoms. Targeted search with relevant keywords and display campaigns on Google search engine and Facebook social media platform were used to reach large numbers of subjects. A report was autogenerated, which included a summary of a subject's symptoms, likely or likely not TN diagnosis, and information to seek appropriate medical assistance. Results: The website was live for seven weeks and generated 240 screening questionnaire submissions, with a total spending of $2482. Forty-four subjects (18.3%) that reported typical symptoms of TN experienced unilateral and episodic pain in one of the trigeminal nerve regions. Conclusions: We have demonstrated the feasibility of social media advertisement and digitally screening a general population for TN, gathering valuable clinical data, such as pain characteristics, through a web-based questionnaire. Based on these data, patients with similar symptoms of TN are suggested to consult a neurologist for diagnosis. This study provides a framework for using digital screening tools to improve the healthcare experience of patients who would spend several months before finding appropriate diagnosis for their specific conditions.

10.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 32(12): 1621-3, 2012 Dec.
Artigo em Zh | MEDLINE | ID: mdl-23469599

RESUMO

OBJECTIVE: To observe the clinical efficacy of Yiqi Fumai Injection (YFI) combined hydroxychloroquine sulfate tablet in the treatment of Sjogren's syndrome patients. METHODS: Eighty patients were randomly assigned to three groups. Forty patients in Group A were treated with YFI alone, 2. 6 g YFI added in 250 mL normal saline for intravenous dripping, once daily. Twenty patients in Group B took hydroxychloroquine sulfate alone, 0. 2 g each time, twice daily. Twenty patients in Group C were treated with YFI and hydroxychloroquine sulfate tablet (with the same dose and dosage as Group A and B). Fifteen days was taken as one course of treatment. The scores for dry mouth and dry eyes, the efficacy on salivary flow rate, Schirmer test, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and IgG, and so on were compared among the three groups before and after treatment. RESULTS: There was no significant difference in the laboratory parameters and clinical symptoms among the three groups before treatment. After treatment obvious improvement of the scores for dry mouth, the salivary flow rate, Schirmer test, ESR, CRP, and IgG was shown in all the 3 groups (P<0.05). Besides, the optimal effect was shown in Group C. Its total effective rate was 85% (17/20), better than that of Group A [80% (32/40)] and Group B [75% (15/20)], with no statistical difference (chi2 = 0.736 and 0. 695, P>0.05). CONCLUSION: YFU combined hydroxychloroquine sulfate tablet showed better effects in treating Sjogren's syndrome patients than using Chinese medicine or Western medicine alone.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Hidroxicloroquina/uso terapêutico , Síndrome de Sjogren/tratamento farmacológico , Adulto , Idoso , Feminino , Humanos , Injeções , Masculino , Pessoa de Meia-Idade
11.
Mol Cells ; 45(6): 365-375, 2022 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-35680372

RESUMO

Long non-coding RNAs (lncRNAs) may be important regulators in the progression of ankylosing spondylitis (AS). The competing endogenous RNA (ceRNA) activity of lncRNAs plays crucial roles in osteogenesis. We identified the mechanism of the differentially expressed lncRNA MALAT1 in AS using bioinformatic analysis and its ceRNA mechanism. The interaction of MALAT1, microRNA-558, and GSDMD was identified using integrated bioinformatics analysis and validated. Loss- and gain-of-function assays evaluated their effects on the viability, apoptosis, pyroptosis and inflammation of chondrocytes in AS. We found elevated MALAT1 and GSDMD but reduced miR-558 in AS cartilage tissues and chondrocytes. MALAT1 contributed to the suppression of cell viability and facilitated apoptosis and pyroptosis in AS chondrocytes. GSDMD was a potential target gene of miR-558. Depletion of MALAT1 expression elevated miR-558 by inhibiting GSDMD to enhance cell viability and inhibit inflammation, apoptosis and pyroptosis of chondrocytes in AS. In summary, our key findings demonstrated that knockdown of MALAT1 served as a potential suppressor of AS by upregulating miR-558 via the downregulation of GSDMD expression.


Assuntos
MicroRNAs , RNA Longo não Codificante , Espondilite Anquilosante , Apoptose/genética , Proliferação de Células/genética , Condrócitos/metabolismo , Humanos , Inflamação/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Piroptose/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Espondilite Anquilosante/genética , Espondilite Anquilosante/metabolismo
12.
ACS Appl Mater Interfaces ; 14(48): 53677-53689, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36399399

RESUMO

As a result of the absence of solid-state diffusion limitation, intercalation pseudocapacitance behavior is emerging as an attractive charge-storage mechanism that can greatly facilitate the ion kinetics to boost the rate capability and cycle stability of batteries; however, related research in the field of zinc-ion batteries (ZIBs) is still in the initial stage and only found in limited cathode materials. In this study, a novel V2O5-x@rGO hybrid aerogel consisting of ultrathin V2O5 nanosheets (∼1.26 nm) with abundant oxygen vacancies (Vö) and a three-dimensional (3D) graphene conductive network was specifically designed and used as a freestanding and binder-free electrode for ZIBs. As expected, the ideal microstructure of both the material and the electrode enable fast electron/ion diffusion kinetics of the electrode, which realize a typical intercalation pseudocapacitance behavior as demonstrated by the simulation calculation of cyclic voltammetry (CV), ex situ X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and first-principles density functional theory (DFT) calculation. Thanks to the elimination of solid-state diffusion limitation, the V2O5-x@rGO electrode delivers a high reversible rate capacity of 153.9 mAh g-1 at 15 A g-1 and 90.6% initial capacity retention at 0.5 A g-1 after 1050 cycles in ZIBs. The intercalation pseudocapacitance behavior is also realized in the assembled soft-pack battery, showing promising practical application prospects.

13.
J Neural Eng ; 19(3)2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35617937

RESUMO

Objective.An understanding of functional interhemispheric asymmetry in ischemic stroke patients is a crucial factor in the designs of efficient programs for post-stroke rehabilitation. This study evaluates interhemispheric synchronization and cortical activities in acute stroke patients with various degrees of severity and at different post-stroke stages.Approach.Twenty-three patients were recruited to participate in the experiments, including resting-state and speed finger-tapping tasks at week-1 and week-3 post-stroke. Multichannel near-infrared spectroscopy (NIRS) was used to measure the changes in hemodynamics in the bilateral prefrontal cortex (PFC), the supplementary motor area (SMA), and the sensorimotor cortex (SMC). The interhemispheric correlation coefficient (IHCC) measuring the synchronized activities in time and the wavelet phase coherence (WPCO) measuring the phasic activity in time-frequency were used to reflect the symmetry between the two hemispheres within a region. The changes in oxyhemoglobin during the finger-tapping tasks were used to present cortical activation.Main results.IHCC and WPCO values in the severe-stroke were significantly lower than those in the minor-stroke at low frequency bands during week-3 post-stroke. Cortical activation in all regions in the affected hemisphere was significantly lower than that in the unaffected hemisphere in the moderate-severe stroke measured in week-1, however, the SMC activation on the affected hemisphere was significantly enhanced in week-3 post-stroke.Significance.In this study, non-invasive NIRS was used to observe dynamic synchronization in the resting-state based on the IHCC and WPCO results as well as hemodynamic changes in a motor task in acute stroke patients. The findings suggest that NIRS could be used as a tool for early stroke assessment and evaluation of the efficacy of post-stroke rehabilitation.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Hemodinâmica , Humanos , Oxiemoglobinas , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Acidente Vascular Cerebral/diagnóstico , Reabilitação do Acidente Vascular Cerebral/métodos
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 31(10): 2839-42, 2011 Oct.
Artigo em Zh | MEDLINE | ID: mdl-22250567

RESUMO

In the present paper, oxalic acid was used to reduce V(V) ion to V(IV) ion, then its complex with V(IV) was formed. By this method, four valence states of vanadium ions had different characteristic absorption peaks in the UV-Visible range. Based on these characteristic absorption peaks, qualitative and quantitative spectrophotometric analysis methods for different valence states of vanadium in vanadium battery electrolyte were established. The results showed that the related coefficients of four standard curves of different valence states were greater than 0.999 0, linearity ranges were 0.326-2.445, 0.326 -2.445, 0.720-5.403, and 1.784-13.437 g x L(-1), respectively. The measurement of samples suggested that the spectrophotometric analysis method was suitable for analyzing the concentration of valence states of vanadium with the RSDs (n = 6) in the range of 0.594%-3.535%.

15.
Cancer Manag Res ; 13: 8663-8672, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34849023

RESUMO

INTRODUCTION: Sunitinib-induced diarrhea seriously affects the prognosis of patients with metastatic renal cell carcinoma (mRCC) and reduces their quality of life. We aim to explore and find the relationship between sunitinib-induced diarrhea and gut microbiota. METHODS: Feces were collected from 31 mRCC patients receiving sunitinib treatment. To characterize the feces gut microbiome profiles of patients, the V3-V4 region of 16S rRNA sequencing was carried out in this study. RESULTS: Gut microbial diversity was decreased both in the severe diarrhea group and in the sunitinib-post group. The microbial composition with higher abundance of Bacteroides (mucus degrading bacteria) and lower abundance of Faecalibacterium, Oscillospira, Ruminococcaceae, Eubacterium and Coriobacteriaceae (butyrate-producing bacteria) were found in patients with diarrhea. Interestingly, the abundance of Actinobacteria was decreased in patients receiving sunitinib with severe diarrhea. CONCLUSION: This study reported an association between gut microbiota and sunitinib-induced diarrhea. Defects of the butyrate-producing bacteria and the increase in Bacteroides may be the physiological basis of sunitinib-induced diarrhea.

16.
IEEE Trans Biomed Eng ; 67(5): 1357-1365, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31442965

RESUMO

Implanted electronics require protection from the body's fluids to avoid moisture induced failure. This study presents an injection molded liquid crystal polymer (LCP) package to protect active implantable devices for chronic applications, such as in optogenetic research. The technology is applied and assessed through a custom package for a fully implantable optogenetic stimulation system, built on a versatile telemetry system that can incorporate additional stimulating and recording channels. An adapted quasi-steady state model predicts the lifetime of an enclosure, where the definition of the lifetime is the time before the internal relative humidity (RH) reaches a time constant, or 63%RH, a conservative limit to minimize the risk of corrosion. The lifetime of the LCP optogenetic device is 94 days, and can be extended to 326 days with the inclusion of 5% w/v silica gel desiccant. Samples of the LCP optogenetic device containing humidity sensors testing in saline at 38 °C support the RH change predictions. Desiccants inside the implant enclosure can store permeating moisture and prolong the life expectancy of LCP-based implants to years or decades. The results of this study demonstrates the feasibility of providing reliable protection for chronic optogenetic implants, and the technology can be transferred to other applications as an easily-manufactured, cost-effective, radiofrequency compatible alternative to hermetic packaging for chronic studies.


Assuntos
Optogenética , Próteses e Implantes , Polímeros , Telemetria
17.
Theranostics ; 10(18): 8227-8249, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32724468

RESUMO

The regenerative capacity of the peripheral nervous system is closely related to the role that Schwann cells (SCs) play in construction of the basement membrane containing multiple extracellular matrix proteins and secretion of neurotrophic factors, including laminin (LN) and brain-derived neurotrophic factor (BDNF). Here, we developed a self-assembling peptide (SAP) nanofiber hydrogel based on self-assembling backbone Ac-(RADA)4-NH2 (RAD) dual-functionalized with laminin-derived motif IKVAV (IKV) and a BDNF-mimetic peptide epitope RGIDKRHWNSQ (RGI) for peripheral nerve regeneration, with the hydrogel providing a three-dimensional (3D) microenvironment for SCs and neurites. Methods: Circular dichroism (CD), atomic force microscopy (AFM), and scanning electron microscopy (SEM) were used to characterize the secondary structures, microscopic structures, and morphologies of self-assembling nanofiber hydrogels. Then the SC adhesion, myelination and neurotrophin secretion were evaluated on the hydrogels. Finally, the SAP hydrogels were injected into hollow chitosan tubes to bridge a 10-mm-long sciatic nerve defect in rats, and in vivo gene expression at 1 week, axonal regeneration, target muscular re-innervation, and functional recovery at 12 weeks were assessed. Results: The bioactive peptide motifs were covalently linked to the C-terminal of the self-assembling peptide and the functionalized peptides could form well-defined nanofibrous hydrogels capable of providing a 3D microenvironment similar to native extracellular matrix. SCs displayed improved cell adhesion on hydrogels with both IKV and RGI, accompanied by increased cell spreading and elongation relative to other groups. RSCs cultured on hydrogels with IKV and RGI showed enhanced gene expression of NGF, BDNF, CNTF, PMP22 and NRP2, and decreased gene expression of NCAM compared with those cultured on other three groups after a 7-day incubation. Additionally, the secretion of NGF, BDNF, and CNTF of RSCs was significantly improved on dual-functionalized peptide hydrogels after 3 days. At 1 week after implantation, the expressions of neurotrophin and myelin-related genes in the nerve grafts in SAP and Autograft groups were higher than that in Hollow group, and the expression of S100 in groups containing both IKV and RGI was significantly higher than that in groups containing either IKV or RGI hydrogels, suggesting enhanced SC proliferation. The morphometric parameters of the regenerated nerves, their electrophysiological performance, the innervated muscle weight and remodeling of muscle fibers, and motor function showed that RAD/IKV/RGI and RAD/IKV-GG-RGI hydrogels could markedly improve axonal regeneration with enhanced re-myelination and motor functional recovery through the synergetic effect of IKV and RGI functional motifs. Conclusions: We found that the dual-functionalized SAP hydrogels promoted RSC adhesion, myelination, and neurotrophin secretion in vitro and successfully bridged a 10-mm gap representing a sciatic nerve defect in rats in vivo. The results demonstrated the synergistic effect of IKVAV and RGI on axonal regrowth and function recovery after peripheral nerve injury.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/imunologia , Laminina/imunologia , Regeneração Nervosa/imunologia , Oligopeptídeos/imunologia , Fragmentos de Peptídeos/imunologia , Traumatismos dos Nervos Periféricos/terapia , Alicerces Teciduais/química , Animais , Fator Neurotrófico Derivado do Encéfalo/química , Linhagem Celular , Dendrímeros/química , Modelos Animais de Doenças , Epitopos/imunologia , Humanos , Hidrogéis/química , Masculino , Nanofibras/química , Oligopeptídeos/química , Traumatismos dos Nervos Periféricos/patologia , Traumatismos dos Nervos Periféricos/fisiopatologia , Ratos , Recuperação de Função Fisiológica/imunologia , Células de Schwann , Nervo Isquiático/lesões , Nervo Isquiático/patologia , Nervo Isquiático/fisiopatologia
18.
Acta Biomater ; 85: 294-309, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30553873

RESUMO

Magnesium ions (Mg2+) are bioactive and proven to promote bone tissue regeneration, in which the enhancement efficiency is closely related to Mg2+ concentrations. Currently, there are no well-established bone tissue engineering scaffolds that can precisely control Mg2+ release, although this capability could have a marked impact in bone regeneration. Leveraging the power of biodegradable microspheres to control the release of bioactive factors, we developed lactone-based biodegradable microspheres that served as both injectable scaffolds and Mg2+ release system for bone regeneration. The biodegradable microsphere (PMg) was prepared from poly(lactide-co-glycolide) (PLGA) microspheres co-embedded with MgO and MgCO3 at a fixed total loading amount (20 wt%) with different weight ratios (1:0; 3:1; 1:1; 1:3; 0:1). The PMg microspheres demonstrated controlled release of Mg2+ by tuning the MgO/MgCO3 ratios. Specifically, faster release with higher initial concentrations of Mg2+ were detected at higher MgO fractions, while long-term sustained release with lower concentrations of Mg2+ was obtained at higher MgCO3 fractions. All prepared PMg microspheres were non-cytotoxic. Furthermore, they promoted attachment, proliferation, osteogenic differentiation, especially, cell migration of bone marrow mesenchymal stromal cells (BMSCs). Among these microspheres, PMg-III microspheres (MgO/MgCO3 in 1:1) exhibited the strongest promotion of mineral depositions and osteogenic differentiation of BMSCs. PMg-III microspheres were injected into the critical-sized calvarial defect of a rat model, resulting in significant bone regeneration when compared to the control group filled with PLGA microspheres. In the PMg-III group, the new bone volume fraction (BV/TV) and bone mineral density (BMD) reached 32.9 ±â€¯5.6% and 325.7 ±â€¯20.2 mg/cm3, respectively, which were much higher than the values 8.1 ±â€¯2.5% (BV/TV) and 124 ±â€¯35.8 mg/cm3 (BMD) in the PLGA group. These findings indicated that bioresorbable microspheres possessing controlled Mg2+ release features were efficient in treating bone defects and promising for future in vivo applications. STATEMENT OF SIGNIFICANCE: Magnesium plays pivotal roles in regulating osteogenesis, which exhibits concentration-dependent behaviors. However, no generally accepted controlled-release system is reported to correlate Mg2+ concentration with efficient bone regeneration. Biodegradable microspheres with injectability are excellent cell carriers for tissue engineering, moreover, good delivery systems for bioactive factors. By co-embedding magnesium compounds (MgO, MgCO3) with different dissolution rates in various ratios, tunable release of Mg2+ from the microspheres was readily achieved. Accordingly, significant promotion in bone defect regeneration is achieved with microspheres displaying proper sustained release of Mg2+. The developed strategy may serve as valuable guidelines for bone tissue engineering scaffold design, which allows precise control on the release of bioactive metal ions like Mg2+ toward potential clinical translation.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Injeções , Magnésio/farmacologia , Microesferas , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Animais , Antibacterianos/farmacologia , Calcificação Fisiológica/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Íons , Osteogênese/efeitos dos fármacos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/administração & dosagem , Ratos Sprague-Dawley , Crânio/diagnóstico por imagem , Crânio/efeitos dos fármacos , Crânio/patologia , Microtomografia por Raio-X
19.
ACS Omega ; 4(13): 15729-15733, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31572876

RESUMO

Plastic products have brought us great convenience in our daily life and work. But in the meantime, waste plastics have become solid pollutants in the environment due to its poor degradability. The resource utilization of waste plastic can decrease environmental pollution. Here, a thermal reduction method for the conversion of waste polyethylene to ZnCCo3 and ZnCNi3 in a stainless-steel autoclave under mild conditions has been reported. X-ray powder diffraction patterns indicate that the obtained samples are anti-perovskite-structured ternary carbides (ZnCCo3 and ZnCNi3) with good crystallinity. Moreover, the formation mechanism of ternary carbides has been briefly discussed. This method can be developed into an effective method for disposal of other waste plastics.

20.
Oncotarget ; 9(35): 23944-23959, 2018 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-29844864

RESUMO

This study investigated whether microRNA-146a (miR-146a) mediating TLR4/NF-κB pathway affected proliferation and inflammatory responses of rheumatoid arthritis fibroblast-like synoviocytes from 12 RA patients (RA-FLSs). FLSs in the logarithmic growth phase were assigned into the control, miR-146a mimic miR-146a inhibitor, Tak-242 (treated with TLR4/NF-κB pathway inhibitor) and mimic + lipopolysaccharide (LPS) groups. Cell proliferation and apoptosis were detected using CCK-8 assay and flow cytometry. The expression of miR-146a, TLR4/NF-κB pathway-related proteins and cytokines were determined by RT-qPCR, western blotting and ELISA, and the release of NO by Greiss reaction. RA rat models were constructed and the primary cells were classified into the control, negative control (NC), miR-146a mimic, miR-146a inhibitor, Tak-242, mimic + LPS, and TLR4 groups. Immunohistochemistry was used to detect the expression of proliferating cell nuclear antigen (PCNA) and intercellular adhesion molecular-1 (ICAM-1). The results showed that miR-146a levels were lower in RA-FLSs than control fibroblasts. miR-146a mimic and Tak-242 decreased RA-FLS proliferation and increased RA-FLS apoptosis, while miR-146a inhibitor had an opposite trend. miR-146a mimic and Tak-242 also decreased expression of TLR4, NF-κB, IL-1ß, IL-6, IL-8, IL-17, COX-2, MMP-3, Seprase, and iNOS, as well as reduced NO level in RA-FLSs while miR-146a inhibitor and TLR4 increased them. TLR4 and NF-κB levels and the positive rates of PCNA and ICAM-1 expressions were lower in RA-FLSs from RA rats given miR-146a mimic from control or miR-146a inhibitor-treated rats. These results suggest that miR-146a inhibits the proliferation and inflammatory response of RA-FLSs by down-regulating TLR4/NF-κB pathway.

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