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Silicon nanowire is a potential candidate to be used as polarization-sensitive material, but the relative mechanism of polarization response must be carried out. Herein, a sub-micron metal-single silicon nanowire-metal photodetector exhibits polarization-sensitive characteristics with an anisotropic photocurrent ratio of 1.59 at 780â nm, an excellent responsivity of 24.58â mA/W, and a high detectivity of 8.88 × 109 Jones at 980â nm. The underlying principle of optical anisotropy in silicon nanowire is attributed to resonance enhancement verified by polarizing light microscopy and simulation. Furthermore, Stokes parameter measurements and imaging are all demonstrated by detecting the characteristics of linearly polarized light and imaging the polarizer array, respectively. Given the maturity of silicon processing, the sub-micron linearly polarized light detection proposed in this study lays the groundwork for achieving highly integrated, simplified processes, and cost-effective on-chip polarization-sensitive optical chips in the future.
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The pBp structure can effectively suppress the dark current of a photodetector by blocking the majority of carriers. However, it is a big challenge to carry out large-scale simulation optimization for two-dimensional (2D) pBp heterojunction photodetectors due to a lack of the device models. Here, a numerical simulation model of the 2D pBp heterojunction was established based on the finite element method to solve this problem. Using this model, the spatial distribution of the energy band is clarified for each layer. The concentration of nonuniformly distributed electrons, induced by the incident light and bias voltage, is obtained by solving the diffusion and drift equations. The characteristics of the photocurrent and the dark current could be presented and the quantum efficiency could be calculated by counting the ratio of the number of carriers collected at the terminals and the carriers photogenerated. The material parameters could be modified for the optimization of the simulation and prediction. In using our model, a B P/M o S 2/graphene photodetector was constructed, and the simulation results show that it works effectively under a reverse bias ranging from -0.3 to 0 V. The external quantum efficiency is 18%, while the internal efficiency approaches 85%. The doping in the barrier region definitely does not affect the dark current and the photocurrent. These results are similar to experimental results published earlier. In addition, with the BP bandgap width of 0.8 eV and incident wavelength of 1.7 µm, the dark current density predicted by the model could reach 3.3×10-8 A/c m 2, which is two orders lower than the reported 2D photodetectors at room temperature. This proposed model provides a way to design 2D pBp heterojunction photodetectors.
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(1) The vicious cycle of innate immune response and reactive oxygen species (ROS) generation is an important pathological process of osteoarthritis (OA). Melatonin may be a new hope for the treatment of OA because of its antioxidant capacity. However, the mechanism of melatonin in the treatment of OA is still not completely clear, and the physiological characteristics of articular cartilage make melatonin unable to play a long-term role in OA. (2) The effects of melatonin on ROS and the innate immune response system in OA chondrocytes and the therapeutic effect in vivo were evaluated. Then, a melatonin-loaded nano-delivery system (MT@PLGA-COLBP) was prepared and characterized. Finally, the behavior of MT@PLGA-COLPB in cartilage and the therapeutic effect in OA mice were evaluated. (3) Melatonin can inhibit the activation of the innate immune system by inhibiting the TLR2/4-MyD88-NFκB signal pathway and scavenging ROS, thus improving cartilage matrix metabolism and delaying the progression of OA in vivo. MT@PLGA-COLBP can reach the interior of cartilage and complete the accumulation in OA knee joints. At the same time, it can reduce the number of intra-articular injections and improve the utilization rate of melatonin in vivo. (4) This work provides a new idea for the treatment of osteoarthritis, updates the mechanism of melatonin in the treatment of osteoarthritis, and highlights the application prospect of PLGA@MT-COLBP nanoparticles in preventing OA.
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Cartilagem Articular , Melatonina , Nanopartículas , Osteoartrite , Camundongos , Animais , Melatonina/farmacologia , Melatonina/uso terapêutico , Melatonina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Preparações de Ação Retardada/farmacologia , Osteoartrite/metabolismo , Condrócitos/metabolismo , Cartilagem Articular/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/farmacologiaRESUMO
Low responsiveness to anti-programmed death-1/programmed death-ligand 1 (anti-PD-1/PD-L1) for solid tumors indicates the presence of other immunosuppressive pathways. Siglec15, a newly discovered immune checkpoint, has been reported to repress immune responses in the tumor microenvironment (TME) and regulate osteoclast differentiation. However, the role of Siglec15 in the treatment for bone metastasis remains unclear. Herein, Siglec15 shows significantly higher expression in lung adenocarcinoma spinal metastasis (LUAD-SM) than in para-cancerous spinal tissues and primary LUAD. Subsequently, a TME-responsive hollow MnO2 nanoplatform (H-M) loaded with Siglec15 siRNA and cisplatin (H-M@siS15/Cis) is developed, and the surface is modified with an aspartic acid octapeptide (Asp8 ), thus allowing H-M to target spinal metastasis. High drug-loading capacity, good biocompatibility, effective tumor accumulation, and efficient Siglec15 silencing are demonstrated. Furthermore, the nanoparticles could reverse immunosuppression caused by tumor cells and tumor-associated macrophages (TAMs) and inhibit osteoclast differentiation via Siglec15 downregulation in vitro. In a LUAD-SM mouse model, H-M@siS15/Cis-Asp8 exhibits superior therapeutic efficacy via synergetic immunochemotherapy and osteolysis inhibition. Taken together, this single nanoplatform reveals the therapeutic potential of the new immune checkpoint Siglec15 in LUAD-SM and provides a strategy to treat this disease.
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Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Osteólise , Neoplasias da Coluna Vertebral , Animais , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Compostos de Manganês , Camundongos , Osteólise/tratamento farmacológico , Óxidos , Neoplasias da Coluna Vertebral/tratamento farmacológico , Microambiente TumoralRESUMO
BACKGROUND: Obstructive sleep apnea (OSA) has a high incidence and is harmful to health. It is characterized by repeated collapse of the upper airway. However, the mechanism underlying upper airway collapse is unclear. METHODS: Patients with OSA and chronic tonsillitis were studied. Pathological changes in palatopharyngeus muscle were detected. The expression of peroxisome proliferator-activated receptor-γ co-activator-1α (PGC-1α) and nuclear respiratory factor-1 (NRF-1) in muscles was detected by PCR and Western blotting. Immunofluorescence staining was used to detect the expression of type I and type II myofibril. RESULTS: The structure of the palatopharyngeus muscle was changed, and the expression of PGC-1α and NRF-1 was decreased in the OSA group compared with that in the control group. The expression of PGC-1α, NRF-1, and type I myofibril in C2C12 myoblasts was decreased by intermittent hypoxia exposure. The expression of type I myofibril was decreased when knocking down PGC-1α. CONCLUSION: OSA patients exhibited pathological damage in palatopharyngeus muscle. PGC-1α was involved in the fiber type conversion in palatopharyngeus muscle caused by intermittent hypoxia.
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Fator 1 Nuclear Respiratório , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Músculos Faríngeos , Apneia Obstrutiva do Sono , Humanos , Hipóxia , Fator 1 Nuclear Respiratório/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Músculos Faríngeos/metabolismoRESUMO
Subwavelength grating structure has excellent filtering characteristics, and its traditional design method needs a lot of computational costs. This work proposed a design method of two-dimensional subwavelength grating filter based on a series feedback neural network, which can realize forward simulation and backward design. It was programed in Python to study the filtering characteristics of two-dimensional subwavelength grating in the range of 0.4-0.7 µm. The shape, height, period, duty cycle, and waveguide layer height of two-dimensional subwavelength grating were taken into consideration. The dataset, containing 46,080 groups of data, was generated through numerical simulation of rigorous coupled-wave analysis (RCWA). The optimal network was five layers, 128 × 512 × 512 × 128 × 61 nodes, and 64 batch size. The loss function of the series feedback neural network is as low as 0.024. Meanwhile, it solves the problem of non-convergence of the network reverse design due to the non-uniqueness of data. The series feedback neural network can give the geometrical structure parameters of two-dimensional subwavelength grating within 1.12 s, and the correlation between the design results and the theoretical spectrum is greater than 0.65, which belongs to a strong correlation. This study provides a new method for the design of two-dimensional subwavelength grating, which is quicker and more accurate compared with the traditional method.
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Aprendizado Profundo , Retroalimentação , Desenho de Equipamento , Simulação por Computador , Redes Neurais de ComputaçãoRESUMO
Nucleic acid aptamers are small fragments of DNA or RNA molecules binding specifically to targets, which can be obtained through in vitro screening via systematic evolution of ligands by exponential enrichment (SELEX). Lactate dehydrogenase (LDH) is an important tumor marker, whose level in patients is of great significance for diagnosis of many diseases. Here, we report the identification of LDH aptamers by 9 rounds of screening from a length-mixed single-stranded DNA library using the SELEX technology. After the 3rd and 7th rounds of aptamer screening, affinity was significantly improved, and fluorescence quantitative analysis showed stronger affinity for the aptamers selected from the 7th to 9th rounds of screening. After high-throughput sequencing, motif analysis, and secondary structure prediction, we finally chose and further investigated 15 candidate LDH aptamer sequences with obvious differences in secondary structure in the 7th to 9th rounds of screening. Among them, LDH7-1, LDH7-9, LDH8-2, and LDH9-1 were shown to bind to LDH protein with high affinity and specificity with Kd < 25 nM. This study provides new ideas for rapid detection of LDH protein content and enzyme activity, thus contributing to the development of rapid medical detection.
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Aptâmeros de Nucleotídeos/química , DNA de Cadeia Simples/química , L-Lactato Desidrogenase/química , Técnica de Seleção de Aptâmeros/métodos , Sequência de Bases , Sítios de Ligação , HumanosRESUMO
PURPOSE: This systematic review and meta-analysis of all available evidence was performed to assess the safety and efficacy of surgery for lumbar stenosis and spondylolisthesis in patients 80 years or older versus those younger than 80 years. METHODS: A search of the literature was conducted in PubMed/MEDLINE, EMBASE and the Cochrane Collaboration Library. Relevant studies comparing the clinical outcomes of lumbar surgery in octogenarians and younger patients were selected according to the eligibility criteria. The predefined endpoints were extracted and meta-analysed from the identified studies. RESULTS: Data from 16 observational studies including 374,197 patients were included in the final analysis. The pooled data revealed that patients 80 years or older had a significantly higher incidence of overall complication, mortality, readmission and longer length of hospital stay than younger patients. There was a similar improvement in the clinical symptoms (Oswestry Disability Index and pain) of patients in the two groups. No significant differences in overall wound complication, reoperation rate, operative time and intraoperative blood loss were found between the groups. CONCLUSIONS: Our results revealed that the clinical improvement in pain and disability did not significantly differ according to age, although the patients aged 80 years or older had increased incidences of mortality and complication than younger patients. Age alone is not a contraindication for lumbar surgery in very old patients. A careful preoperative evaluation, proper patient selection and appropriate surgical approach are important to achieve successful surgical outcomes. These slides can be retrieved under Electronic Supplementary Material.
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Fusão Vertebral , Estenose Espinal , Espondilolistese , Idoso de 80 Anos ou mais , Constrição Patológica , Humanos , Vértebras Lombares/cirurgia , Região Lombossacral/cirurgia , Estenose Espinal/cirurgia , Espondilolistese/cirurgia , Resultado do TratamentoRESUMO
BACKGROUND Several factors determine the efficacy of warfarin anticoagulation in patients with non-valvular atrial fibrillation (NVAF). This study aimed to use data from the Chinese Atrial Fibrillation Registry study to assess the control of anticoagulation therapy in Chinese patients with NVAF treated with warfarin. MATERIAL AND METHODS From the Chinese Atrial Fibrillation Registry study the anticoagulant use and dosing, the time in therapeutic range (TTR) of the international normalized ratio (INR), and standard deviation of the observed INR values (SDINR), and their influencing factors were evaluated. RESULTS The median INR and SDINR were 2.04 (IQR 1.71-2.41) and 0.50 (IQR, 0.35-0.69), respectively. The median TTR was 51.7% (IQR, 30.6-70.1%) and only 25.1% had a TTR ≥70%. Age was ≥70 years (OR, 0.72; 95% CI, 0.55-0.94; P=0.015), bleeding history (OR 0.48; 95% CI, 0.23-0.89; P=0.029), the use of a single drug (OR, 0.62; 95% CI, 0.42-0.92; P=0.016), more than drug (OR, 0.60; 95% CI, 0.41-0.88; P=0.009), and lack of assessment of bleeding risk (OR, 0.72; 95% CI, 0.54-0.97; P=0.033) were associated with TTR <70% (INR 2.0-3.0). Coronary heart disease (CHD) and peripheral artery disease (PAD) (OR, 0.69; 95% CI, 0.52-0.90; P=0.007) and diabetes mellitus (OR, 0.79; 95% CI, 0.62-0.99; P=0.044) were associated with increased variability in INR (SDINR ≥0.5). CONCLUSIONS In Chinese patients with NVAF, warfarin anticoagulation was associated with lower TTR and less stable anticoagulation than in current guidelines, and risk factors for reduced safety and efficacy were identified.
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Fibrilação Atrial/tratamento farmacológico , Terapia Trombolítica/efeitos adversos , Varfarina/farmacologia , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Povo Asiático/genética , Coagulação Sanguínea/efeitos dos fármacos , China , Feminino , Hemorragia/complicações , Humanos , Coeficiente Internacional Normatizado , Masculino , Pessoa de Meia-Idade , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/complicações , Resultado do TratamentoRESUMO
BACKGROUND: The epidemiology and cause of ossification of the spinal ligaments (OSL) remains obscure. To date, there is no study that comprehensively evaluates the prevalence, distribution, and concomitance of each type of OSL by CT among general Chinese population. We therefore aimed to comprehensively investigate epidemiological characteristics of OSL using whole spine CT in the Chinese population and examine the factors that correlate with the presence of OSL. METHODS: Ossification of the posterior longitudinal ligament (OPLL), ligamentum flavum (OLF), anterior longitudinal ligament (OALL), nuchal ligament (ONL), and diffuse idiopathic skeletal hyperostosis (DISH) were evaluated from the subjects who underwent PET/CT for the purpose of cancer screening in our hospital. Prevalence, distribution, and concomitance of OSL were reviewed. Logistic regression analysis was performed to identify the risk factors of OSL. RESULTS: A total of 2000 subjects (1335 men and 665 women) were included. The prevalence rate of cervical OPLL (C-OPLL) was 4.1%, thoracic OPLL (T-OPLL) 2.25%, lumbar OPLL (L-OPLL) 0.8%, thoracic OLF (T-OLF) 37.65%, lumbar OLF (L-OLF) 1.45%, ONL 31.5%, DISH 3.85%. The most commonly involved level was C5 for C-OPLL, T1 for T-OPLL, T10 for T-OLF, and T8/9 for OALL. 21% of subjects with C-OPLL had T-OPLL, 44% of C-OPLL had T-OLF, 38% of T-OPLL had C-OPLL, 53% of T-OPLL had T-OLF, 44% of L-OPLL had T-OPLL, and 56% of L-OPLL had T-OLF. The average age of OSL-positive subjects was significantly higher than that of OSL-negative subjects. The results of the multiple regression analysis revealed that males had a strong association with DISH (odds ratio, 3.15; 95% confidence interval, 1.27-7.78; P = 0.013). CONCLUSION: The prevalence of OSL in the Chinese was revealed. Tandem ossification is not uncommon in people with OSL. There is a high incidence of multiple-regional OPLL in the whole spine. Approximately half of the subjects with OPLL coexist with T-OLF. For patients with clinical symptoms induced by OPLL, thorough evaluation of whole spine using CT is recommended.
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Hiperostose Esquelética Difusa Idiopática/epidemiologia , Ligamentos Articulares/patologia , Ossificação do Ligamento Longitudinal Posterior/epidemiologia , Coluna Vertebral/patologia , Adulto , China , Estudos Transversais , Feminino , Humanos , Hiperostose Esquelética Difusa Idiopática/diagnóstico por imagem , Hiperostose Esquelética Difusa Idiopática/patologia , Incidência , Ligamentos Articulares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Ossificação do Ligamento Longitudinal Posterior/diagnóstico , Ossificação do Ligamento Longitudinal Posterior/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Prevalência , Estudos Retrospectivos , Fatores de Risco , Coluna Vertebral/diagnóstico por imagemRESUMO
PURPOSE: To compare the clinical effectiveness of decompression plus fusion and decompression alone for patients with degenerative lumbar spondylolisthesis, a systematic review and meta-analysis of all available evidence was performed. METHODS: A search of the literature was conducted on PubMed/MEDLINE, EMBASE, and the Cochrane Collaboration Library. Relevant studies comparing decompression plus fusion and decompression alone were selected according to eligibility criteria. Predefined endpoints were extracted and meta-analyzed from the identified studies. RESULTS: Four randomized controlled trials and 13 observational studies were eligible. The pooled data revealed that fusion was associated with significantly higher rates of satisfaction and lower leg pain scores when compared with decompression alone. However, fusion significantly increased the intraoperative blood loss, operative time and hospital stay. Both techniques had similar ODI, back pain scores, complication rate, and reoperation rate. CONCLUSIONS: Based on the available evidence, decompression plus fusion maybe be better than decompression alone in the treatment of degenerative spondylolisthesis. Fusion had advantages of improvement of clinical satisfaction, as well as reduction of postoperative leg pain, with similar complication rate to decompression alone.
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Descompressão Cirúrgica , Vértebras Lombares/cirurgia , Fusão Vertebral , Espondilolistese/cirurgia , Perda Sanguínea Cirúrgica , Descompressão Cirúrgica/efeitos adversos , Descompressão Cirúrgica/métodos , Descompressão Cirúrgica/estatística & dados numéricos , Humanos , Tempo de Internação , Duração da Cirurgia , Fusão Vertebral/efeitos adversos , Fusão Vertebral/métodos , Fusão Vertebral/estatística & dados numéricos , Resultado do TratamentoRESUMO
Mesenchymal stem cells (MSCs) have been isolated and identified separately from the three components of intervertebral disc, i.e. annulus fibrosus (AF), nucleus pulposus (NP), and cartilage endplate (CEP). However, few studies have been carried out to compare the properties of these three kinds of stem cells, especially their migration ability which is essential for their potential clinical application. In this study, MSCs were isolated from AF, NP, and CEP, respectively, of human degenerated discs and identified by surface markers and multilineage differentiation assay at passage 3. These three types of stem cells were named as AF-MSCs, NP-MSCs, and CEP-MSCs. Then, their biological characteristics were compared in terms of proliferation, passage, colony formation, migration, and invasion capacity. Results showed that all the three types of cells were identified as MSCs and had similar characteristics in proliferation, passage, and colony formation capacity. CEP-MSCs showed the highest migration and invasion potency, while NP-MSCs showed the lowest migration ability and almost no invasion potency, suggesting that CEP-MSCs had the most powerful properties of migration and invasion when compared with AF-MSCs and NP-MSCs. It was also found that the expression of CXCR4 was higher in CEP-MSCs than in the other two, suggesting that SDF-1/CXCR4 axis may play significant roles in the migration of these cells.
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Movimento Celular , Quimiocina CXCL12 , Degeneração do Disco Intervertebral , Células-Tronco Mesenquimais , Receptores CXCR4 , Células-Tronco Adultas/patologia , Células-Tronco Adultas/fisiologia , Anel Fibroso/patologia , Anel Fibroso/fisiologia , Biomarcadores/metabolismo , Diferenciação Celular , Movimento Celular/fisiologia , Proliferação de Células , Células Cultivadas , Quimiocina CXCL12/genética , Quimiocina CXCL12/metabolismo , Feminino , Humanos , Degeneração do Disco Intervertebral/genética , Degeneração do Disco Intervertebral/patologia , Masculino , Células-Tronco Mesenquimais/fisiologia , Pessoa de Meia-Idade , Núcleo Pulposo/patologia , Núcleo Pulposo/fisiologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores CXCR4/genética , Receptores CXCR4/metabolismoRESUMO
OBJECTIVES: Overwhelming evidence shows that dietary supplementation with n-3 polyunsaturated fatty acids (PUFAs) elicits protective effects on patients with cardiovascular disease. However, the detailed mechanisms underlying n-3 PUFA-mediated cardioprotection are unknown, and examined in the present study. METHODS: We evaluated heart performances with Langendorff perfusion apparatus. Meanwhile, whole mitochondria were purified from non-perfused hearts for functional assessment, and lipid peroxidation level was measured as well. RESULTS: Compared with control groups, hearts from n-3 PUFA-supplemented rats showed improved functional recovery and reduced tissue injury following ischemia/reperfusion (I/R). Furthermore, the mitochondrial function of PUFA-treated hearts was significantly enhanced, as demonstrated by biochemical analysis of respiratory chain activity. In addition, thiobarbituric acid-reactive substance or TBARS assay revealed that lipid peroxidation product, malondialdehyde or MDA, in the mitochondria was significantly reduced by PUFA treatment. CONCLUSION: Taken together, our data indicate that marine n-3 PUFA could improve cardiac performance after I/R injury by restoring mitochondrial respiratory activities and attenuating lipid peroxidation.
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Ácidos Graxos Ômega-3/uso terapêutico , Óleos de Peixe/uso terapêutico , Peroxidação de Lipídeos/efeitos dos fármacos , Mitocôndrias Cardíacas/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Animais , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Ácidos Graxos Ômega-3/farmacologia , Óleos de Peixe/farmacologia , Técnicas In Vitro , Masculino , Contração Miocárdica/efeitos dos fármacos , Ratos Sprague-DawleyRESUMO
UNLABELLED: Maternal IgG anti-A/B titers have been considered as a susceptible factor to the risk of ABO hemolytic disease in newborn (ABO-HDN). However, the results remain controversial. This meta-analysis aimed to estimate the association between maternal IgG anti-A/B titers and the risk of ABO-HDN. METHODS: Trials on the relationship between maternal IgG anti-A/B titers and the risk of ABO-HDN were collected by searching Embase, PubMed, and Cochrane Central Register of Controlled Trials (CENTRAL) electronic databases. The inclusion criteria were maternal IgG anti-A/B titers screening and the evaluation of clinical outcomes in relation to ABO-HDN. Stata 12.0 was used to analyze the data. RESULTS: A total of 23 trials were eligible for inclusion, of which four trials with 5,246 participants were suitable for this meta-analysis. Meta-analysis results suggested that maternal IgG anti-A/B titers were significantly associated with the risk of ABO-HDN [OR = 2.86, 95% CI = 2.50-3.28; OR = 4.67, 95% CI = 3.92-5.55; OR = 1.61, 95% CI = 1.36-1.91 in titers (128 to 256) vs. titers (64 or lower), titers (512 or higher) vs. titers (64 or lower), and titers (512 or higher) vs. titers (128-256), respectively]. CONCLUSIONS: Our meta-analysis suggests that maternal IgG anti-A/B titers are significantly associated with the risk of ABO-HDN. They contribute to the prediction of risk of ABO-HDN, in addition to the need for invasive treatment for antibody titers ≥512.
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Sistema ABO de Grupos Sanguíneos/imunologia , Eritroblastose Fetal/sangue , Eritroblastose Fetal/imunologia , Imunoglobulina G/sangue , Sistema ABO de Grupos Sanguíneos/sangue , Feminino , Humanos , Recém-Nascido , Mães , Fatores de RiscoRESUMO
Waste printed circuit boards (WPCBs) are composed of nearly 70% non-metals, which are generally recycled as low-value filling materials or even directly dumped in landfills. In this study, polypropylene (PP) composites reinforced by recycled pure glass fibres (RGF) from pyrolysed WPCBs were successfully produced. The manufacturing process, mechanical properties and thermal behaviour of the composites were investigated. The results showed that the appropriate addition of RGF in the composites can significantly improve the mechanical properties and thermal behaviour. When the added content of RGF was 30%, the maximum increment of tensile strength, impact strength, flexural strength and flexural modulus of the glass fibre (GF)/PP composites are 25.93%, 41.38%, 31.16% and 68.42%, respectively, and the vicat softening temperature could rise by 4.6°C. Furthermore, leaching of the GF/PP composites was also investigated. The GF/PP composites exhibited high performance and non-toxicity, offering a promising method to recycle RGF from pyrolysed WPCBs with high-value applications.
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Resíduo Eletrônico , Vidro/química , Polipropilenos/química , Reciclagem/métodos , Eliminação de Resíduos/métodos , Brometos/análise , Metais Pesados/análise , Maleabilidade , Estresse Mecânico , Resistência à Tração , Poluentes Químicos da Água/análiseRESUMO
BACKGROUND: Bone implant infections pose a critical challenge in orthopedic surgery, often leading to implant failure. The potential of implant coatings to deter infections by hindering biofilm formation is promising. However, a shortage of cost-effective, efficient, and clinically suitable coatings persists. Polyvinyl alcohol (PVA), a prevalent biomaterial, possesses inherent hydrophilicity, offering potential antibacterial properties. METHODS: This study investigates the PVA solution's capacity to shield implants from bacterial adhesion, suppress bacterial proliferation, and thwart biofilm development. PVA solutions at concentrations of 5%, 10%, 15%, and 20% were prepared. In vitro assessments evaluated PVA's ability to impede bacterial growth and biofilm formation. The interaction between PVA and mCherry-labeled Escherichia coli (E. coli) was scrutinized, along with PVA's therapeutic effects in a rat osteomyelitis model. RESULTS: The PVA solution effectively restrained bacterial proliferation and biofilm formation on titanium implants. PVA solution had no substantial impact on the activity or osteogenic potential of MC3T3-E1 cells. Post-operatively, the PVA solution markedly reduced the number of Staphylococcus aureus and E. coli colonies surrounding the implant. Imaging and histological scores exhibited significant improvements 2 weeks post-operation. Additionally, no abnormalities were detected in the internal organs of PVA-treated rats. CONCLUSIONS: PVA solution emerges as an economical, uncomplicated, and effective coating material for inhibiting bacterial replication and biofilm formation on implant surfaces, even in high-contamination surgical environments.
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Escherichia coli , Álcool de Polivinil , Ratos , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Próteses e Implantes , Biofilmes , Titânio , Materiais Revestidos Biocompatíveis , Propriedades de SuperfícieRESUMO
Bacterial resilience within biofilms, rendering them up to 1000 times more resistant to antibiotic drugs, poses a formidable challenge. This study introduces a targeted biofilm eradication strategy, termed "target-penetration-killing-eradication", implemented through magnetic micro-robotic technology. Specifically, we present the development of a magnetic-guided nano-antibacterial platform designed for alternating magnetic field (AMF) controlled vancomycin release in the eradication of Staphylococcus aureus biofilms. To address the issue of premature vancomycin release in physiological conditions, we employed a temperature-sensitive linking agent, 4,4'-azobis(4-cyano valeric acid), facilitating the conjugation of vancomycin onto Fe3O4/CS nanocomposites, resulting in the novel construct Fe3O4@CS-ACVA-VH. The release mechanism adheres to first-order kinetics and Fickian diffusion, with each 10-min AMF treatment releasing approximately 8.4 ± 1.1% of vancomycin. The potency of vancomycin in the release solution was similar to that of the original drug (MIC: 7.4 ± 3.5 vs. 5.6 µg/mL). Fe3O4@CS-ACVA-VH exhibited sustained antibacterial efficacy, inhibiting bacterial growth for four consecutive days and preventing the formation of bacterial biofilms on its surface. Contact-inhibition bacterial activity of Fe3O4@CS-ACVA-VH against S. aureus was 0.046875 mg/mL. Conceptually validating our approach, we emphasize Fe3O4@CS-ACVA-VH's exceptional ability to penetrate S. aureus biofilms under static magnetic field attraction. Furthermore, the nano-platform offers the unique advantage of on-demand vancomycin release through alternating magnetic field stimulation, effectively clearing a larger biofilm area. This multifunctional nano-platform demonstrates magnetic-guided biofilm penetration followed by controlled vancomycin release, presenting a promising strategy for enhanced biofilm eradication.
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The 5'-HOXD genes are important for chondrogenesis in vertebrates, but their roles in osteoarthritis (OA) are still ambiguous. In our study, 5'-HOXD genes involvement contributing to cartilage degradation and OA was investigated. In bioinformatics analysis of 5'-HOXD genes, we obtained the GSE169077 data set related to OA in the GEO and analyzed DEGs using the GEO2R tool attached to the GEO. Then, we screened the mRNA levels of 5'-HOXD genes by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). We discovered that OA chondrocyte proliferation was inhibited, and apoptosis was increased. Moreover, it was discovered that SOX9 and COL2A1 were downregulated at mRNA and protein levels, while matrix metalloproteinases (MMPs) and a disintegrin-like and metalloproteinase with thrombospondin motifs (ADAMTSs) were upregulated. According to the results of differentially expressed genes (DEGs) and qRT-PCR, we evaluated the protein level of HOXD11 and found that the expression of HOXD11 was downregulated, reversed to MMPs and ADAMTSs but consistent with the cartilage-specific factors, SOX9 and COL2A1. In the lentivirus transfection experiments, HOXD11 overexpression reversed the effects in OA chondrocytes. In human OA articular cartilage, aberrant subchondral bone was formed in hematoxylin-eosin (H&E) and Safranin O and fast green (SOFG) staining results. Furthermore, according to immunohistochemistry findings, SOX9 and HOXD11 expression was inhibited. The results of this study established that HOXD11 was downregulated in OA cartilage and that overexpression of HOXD11 could prevent cartilage degradation in OA.
Assuntos
Cartilagem Articular , Osteoartrite , Animais , Humanos , Cartilagem Articular/metabolismo , Condrócitos/metabolismo , Metaloproteinases da Matriz/metabolismo , Osteoartrite/genética , Osteoartrite/metabolismo , RNA Mensageiro/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
BACKGROUND: For patients with acute paraplegia caused by spinal giant cell tumor (GCT) who require emergency decompressive surgery, there is still a lack of relevant reports on surgical options. This study is the first to present the case of an acute paraplegic patient with a thoracic spinal GCT who underwent an emergency total en bloc spondylectomy (TES). Despite tumor recurrence, three-level TES was repeated after denosumab therapy. CASE SUMMARY: A 27-year-old female patient who underwent single-level TES in an emergency presented with sudden severe back pain and acute paraplegia due to a thoracic spinal tumor. After emergency TES, the patient's spinal cord function recovered, and permanent paralysis was avoided. The postoperative histopathological examination revealed that the excised neoplasm was a rare GCT. Unfortunately, the tumor recurred 9 months after the first surgery. After 12 months of denosumab therapy, the tumor size was reduced, and tumor calcification. To prevent recurrent tumor progression and provide a possible cure, a three-level TES was performed again. The patient returned to an active lifestyle 1 month after the second surgery, and no recurrence of GCT was found at the last follow-up. CONCLUSION: This patient with acute paraplegia underwent TES twice, including once in an emergency, and achieved good therapeutic results. TES in emergency surgery is feasible and safe when conditions permit; however, it may increase the risk of tumor recurrence.