Quantitative analysis of related parameters of retinal nerve fiber layer and ganglion cell complex thickness in patients with different degrees of Parkinson's disease.

OBJECTIVE: A quantitative analysis was performed to evaluate the morphologic changes of the retinal nerve fiber layer (RNFL) and macular ganglion cell complex (GCC) in patients with Parkinson's disease (PD). METHODS: Thirty PD patients were enrolled, and they were allocated to the mild-to-moderate PD group (n = 15) or severe PD group (n = 15) according to the severity of PD. Twenty healthy volunteers (20 eyes) were included as controls. Optical coherence tomography (OCT) was used to measure the thickness of mean RNFL and each of the sectors: temporal-upper (TU), superior-temporal (ST), superior-nasal (SN), nasal-upper (NU), nasal-lower (NL), inferior-nasal (IN), inferior-temporal (IT), temporal-lower (TL). The thickness of macular GCC, superior GCC, and inferior GCC was also measured. RESULTS: No difference was found between the three groups with respect to age, sex and disease course (p > 0.05). The mean RNFL thickness was 118.15 ± 10.25 µm in the control group, 96.12 ± 9.45 µm in the mild-to-moderate PD group, and 80.48 ± 10.35 µm in the severe PD group. Significant differences were found in the mean RNFL thickness and thickness of TU, IN, IT and TL sectors among the three groups (p < 0.05). These values, mean RNFL, TU, IN, IT, and TL, were lower in both the PD groups than those in the control, among them the severe PD group had the lowest values. A quantitative analysis of the macula GCC was also performed. Overall, there were significant differences in mean macula, superior, and inferior GCC thickness among the three groups (p < 0.05). The two PD groups had lower values of mean macula, superior, and inferior GCC thickness than that in the controls (p < 0.05); and the severe PD group had lowest values of these parameters. CONCLUSION: In this study, significant thinning of RNFL and macular GCC was found in PD patients. The more serious the illness, the more the thickness becomes thinner. The OCT measurement was found useful in detecting the structural alterations in the retina of PD. The technique may be useful in follow-up of the disease progression after further validation.

Analysis and Correction of Measurement Error of Spherical Capacitive Sensor Caused by Assembly Error of the Inner Frame in the Aeronautical Optoelectronic Pod.

The ball joint is a multi-degree-of-freedom transmission pair, if it can replace the inner frame in the aviation photoelectric pod to carry the optical load, which will greatly simplify the system structure of the photoelectric pod and reduce the space occupied by the inner frame. However, installation errors in ball joint siting introduce nonlinear errors that are difficult to correct and two degree of freedom angular displacement of the ball joint is difficult to detect, which limits application in the precision control of two degrees of freedom systems. Studies of spherical capacitive sensors to date have not tested sensors for use in an inner frame stabilisation mechanism nor have they analysed the influence of installation error on sensor output. A two-axis angular experimental device was designed to measure the performance of a ball joint capacitive sensor in a frame stabilisation mechanism in an aeronautical optoelectronic pod, and a mathematical model to compensate for ball joint capacitive sensor installation error was created and tested. The experimental results show that the resolution of the capacitive sensor was 0.02° in the operating range ±4°, the repeatability factor was 0.86%, and the pulse response time was 39 µs. The designed capacitive sensor has a simple structure, high measurement accuracy, and strong robustness, and it can be integrated into ball joint applications in the frames of aeronautical photoelectric pods.

A Novel Method for Detecting the Two-Degrees-of-Freedom Angular Displacement of a Spherical Pair, Based on a Capacitive Sensor.

The spherical pair has an important role in the inner frame of the stabilization mechanism of the aviation optoelectronic pod. However, its two-degrees-of-freedom (2-DOF) angular displacement signal is difficult to detect, seriously restricting its application in aviation optoelectronic pods. Therefore, this study proposes a new method to measure a spherical pair's 2-DOF angular displacement using a spherical capacitive sensor. The capacitive sensor presented by this method realizes the measurement of the 2-DOF angular displacement of the spherical pair by integrating the spherical electrode groups in the ball head and the ball socket of the spherical pair. First, based on the geometric structure of the spherical pair, the structure of the capacitive sensor is designed, and the mathematical model for the capacitive sensor is deduced. Then, the sensor's output capacitance, in different directions, is simulated by Ansoft Maxwell software. Finally, an experiment device is built for the measurement experiments. The simulation analysis and experimental results show that the spherical capacitive sensor has an approximately linear output in different directions, and the measured output capacitance is as high as 89.7% of the theoretical value. Compared with the existing sensors that measure the 2-DOF angular displacement signal of the ball pair, the sensor proposed in this study has an integrated structure, which can be integrated into the spherical pair. That makes it possible to apply the spherical pair to the inner frame of the aviation optoelectronic pod.

Novel Acute Retinal Artery Ischemia and Reperfusion Model in Nonhuman Primates.

BACKGROUND AND PURPOSE: The retina, as an externally located neural tissue, offers unique advantages in investigating the effect of therapeutic intervention on the brain. In this study, we put forth a clinically relevant model of retinal ischemia and reperfusion in nonhuman primates. METHODS: Acute retinal artery ischemia and reperfusion was induced by injecting an autologous clot into the ophthalmic artery of adult rhesus monkeys, and recanalization was achieved by focal thrombolysis with tPA (tissue-type plasminogen activator). Digital subtraction angiography and fluorescein angiography were used to evaluate blood flow in the retina and the choroid. Electroretinogram, optical coherence tomography, and hematoxylin and eosin staining were used to evaluate the structure and function of the retina after ischemia. RESULTS: Digital subtraction angiography and fluorescein angiography images confirmed occlusion of the ophthalmic and central retinal arteries, as well as recanalization after tPA thrombolysis. Electroretinogram indicated retinal functional damage following ischemia, and thrombolysis partially rescued its impairment. Optical coherence tomography and hematoxylin and eosin staining revealed ischemia-induced changes in the retina, and tPA partially mitigated these damages. CONCLUSIONS: This novel acute retinal artery ischemia and reperfusion model in rhesus monkeys may closely simulate retinal ischemia/reperfusion in clinical practice and provide an optimal platform for screening neuroprotective strategies.

Fabry-Perot-resonator-coupled metal pattern metamaterial for infrared suppression and radiative cooling.

The most intuitive approach for infrared stealth, namely, the indiscriminate suppression of thermal radiation, is often at the risk of overheating the target. Spectrally selective metamaterials may solve this problem by satisfying radiative cooling as well as infrared suppression. Therefore, we have designed and fabricated a broadband metamaterial by depositing a Fabry-Perot (F-P) resonator on top of a metal pattern. The composite structure has two absorption peaks, one originating from F-P resonance, the other from the magnetic resonance of the metal pattern, and they can be merged into the 5∼8 µm range through optimization. According to Kirchhoff's law, this results in high emissivity in the 5∼8 µm range (the best choice of nonatmospheric-window ranges) and low emissivity in the 3∼5 µm and 8∼14 µm ranges (the two atmospheric windows), satisfying both infrared suppression and radiative cooling. Energy dissipation distributions indicate apparent coupling of F-P resonance and magnetic resonance, but these two resonances are stronger at their respective intrinsic wavelengths. This paper reveals an alternative method for infrared suppression with radiative cooling, which is also meaningful in the design of broad/multiband absorbers.

Secretogranin III as a novel target for the therapy of choroidal neovascularization.

Wet age-related macular degeneration (AMD) with choroidal neovascularization (CNV) is a leading cause of vision loss in the elderly. The advent of anti-vascular endothelial growth factor (VEGF) drugs represents a major breakthrough in wet AMD therapy but with limited efficacy to improve visual acuity. Secretogranin III (Scg3, SgIII) was recently discovered as a novel angiogenic factor with VEGF-independent mechanisms. Scg3-neutralizing monoclonal antibody (mAb) was reported to alleviate pathological retinal neovascularization in oxygen-induced retinopathy mice and retinal vascular leakage in diabetic mice with high efficacy and disease selectivity. Herein we investigated whether Scg3 is a novel angiogenic target for CNV therapy in mouse models. We found that anti-Scg3 ML49.3 mAb inhibited Scg3-induced proliferation and Src phosphorylation in human retinal microvascular endothelial cells. Intravitreal injection of Scg3-neutralizing polyclonal antibodies (pAb) or mAb significantly attenuated laser-induced CNV leakage, CNV 3D volume, lesion area and vessel density. Furthermore, subcutaneous administration of Scg3-neutralizing pAb or mAb significantly prevented Matrigel-induced CNV. The efficacy of anti-Scg3 pAb or mAb was comparable to VEGF inhibitor aflibercept. These findings suggest that Scg3 plays an important role in CNV pathogenesis and that anti-Scg3 mAb efficiently ameliorates laser- or Matrigel-induced CNV.

Subfoveal Choroidal and Macular Thickness Changes after Phacoemulsification Using Enhanced Depth Imaging Optical Coherence Tomography.

PURPOSE: To assess changes in the thickness of the subfoveal retina and choroid after phacoemulsification using enhanced depth imaging optical coherence tomography (EDI-OCT). METHODS: A prospective study was conducted on 100 patients. The subfoveal choroidal thickness (SFCT) was measured at 7 points and the retinal thickness was measured at 5 points (before surgery, and 1 day, 1 week, 1 month, and 3 months after surgery). RESULTS: The foveal choroidal thickness showed a thickening trend (but p > 0.05). Compared to the change from baseline to day 1, the changes from baseline were significantly different at nasal 3 mm and 6 mm at all other time points (all p < 0.05). Choroidal thickness changes at temporal 6 mm correlated negatively with intraocular pressure (IOP) at 1 week and 1 month; changes at nasal 3 mm correlated negatively with IOP at 1 week and 1 month (all p < 0.05); changes at nasal 3 mm, temporal 3 mm, and temporal 6 mm correlated with average ultrasonic energy. Choroidal thickness changes correlated with ultrasound (US) time at day 1. CONCLUSIONS: Uncomplicated phacoemulsification led to changes in choroidal thickness. IOP and choroidal thickness changes were negatively correlated. The foveal retinal thickness was correlated with age. SFCT was correlated with sex, axial length, IOP, and US time.

Synthesis and Evaluation of Bakuchiol Derivatives as Potential Anticancer Agents.

A series of bakuchiol derivatives were synthesized and evaluated for their anti-proliferative and the inhibitory activities on SMMC7721 cell line migration using PX-478 as a positive control. The results showed (S,E)-4-(7-methoxy-3,7-dimethyl-3-vinyloct-1-en-1-yl)phenol (10) to have the best activity among the tested compounds, which included PX-478. In addition, compound 10 showed greater inhibitory activity than that of bakuchiol in the transwell migration and invasion assays at every dose. In western blotting tests, compound 10 showed a promising ability to downregulate the expression of HIF-1α and its associated downstream proteins MMP-2 and MMP-9. Moreover, this effect was dose-dependent and could represent a possible mechanism of action for the anticancer activity of compound 10.

Assessment of intracranial pressure with ultrasonographic retrobulbar optic nerve sheath diameter measurement.

BACKGROUND: Ultrasonograpic retrobulbar optic nerve sheath diameter (ONSD) measurement is considered to be an alternative noninvasive method to estimate intracranial pressure,but the further validation is urgently needed. The aim of the current study was to investigate the association of the ultrasonographic ONSD and intracranial pressure (ICP) in patients. METHODS: One hundred and ten patients whose intracranial pressure measured via lumbar puncture were enrolled in the study. Their retrobulbar ONSD with B-scan ultrasound was determined just before lumber puncture. The correlation between the ICP and the body mass index (BMI), ONSD or age was established respectively with the Pearson correlation coefficient analysis. The discriminant analysis was used to obtain a discriminant formula for predicting ICP with the ONSD、BMI、gender and age. Another 20 patients were recruited for further validation the efficiency of this discriminant equation. RESULTS: The mean ICP was 215.3 ± 81.2 mmH2O. ONSD was 5.70 ± 0.80 mm in the right eye and 5.80 ± 0.77 mm in the left eye. A significant correlation was found between ICP and BMI (r = 0.554, p < 0.001), the mean ONSD (r = 0.61, P < 0.001), but not with age (r = -0.131, p = 0.174) and gender (r = 0.03, p = 0.753). Using receiver operating characteristic (ROC) curve analysis, the critical value for the risk mean-ONSD was 5.6 mm from the ROC curve, with the sensitivity of 86.2% and specificity of 73.1%. With 200 mmH2O as the cutoff point for a high or low ICP, stepwise discriminant was applied, the sensitivity and specificity of ONSD predicting ICP was 84.5%-85.7% and 86.5%-92.3%. CONCLUSIONS: Ophthalmic ultrasound measurement of ONSD may be a good surrogate of invasive ICP measurement. This non-invasive method may be an alternative approach to predict the ICP value of patients whose ICP measurement via lumbar puncture are in high risk. The discriminant formula, which incorporated the factor of BMI, had similar sensitivity and higher specificity than the ROC curve.

Cardiovascular and Cognitive Health Study in Middle-Aged and Elderly Residents of Beijing(CCHS-Beijing): Design and Rationale.

The Cardiovascular and Cognitive Health Study (CCHS-Beijing) is a population-based study of cardiovascular disease (CVD) and cognitive impairment in adults aged 55 and older in Beijing. The main aims of the study are to investigate the prevalence rates of CVD, asymptomatic atherosclerosis, and cognitive impairment, as well as validate the risk factors related to the onset and development of CVD, Alzheimer's disease (AD) and mild cognitive impairment (MCI). The study was designed to detect the traditional and new risk factors in this age group. Participants were recruited randomly from residential regions in the greater Beijing municipality area based on the average levels of development in Beijing, China in 2012 (based on socioeconomic, demographic, and geographical characteristics). Thorough physical and laboratory examination were performed at baseline (also the cross-sectional survey) to identify the risk factors such as hypertension, dyslipidemia, diabetes, as well as newly defined risk factors like elevated homocysteine, high sensitivity C-reactive protein, and urine micro-albumin. Subclinical disease of the cerebral vasculature included atherosclerosis of carotid arteries, intracranial arteries, and retinal vessels. Subclinical cardiac diseases included left ventricular enlargement, arrhythmias, chamber hypertrophy and myocardial ischemia. Blood pressure was documented using the ankle-arm method. In addition, neuropsychological assessments were performed for all subjects aged 65 and above. Baseline evaluation began during the period August 2013 to December 2014. Follow-up examination will occur in 5 years. The initial and recurrent CVD, AD and MCI events will be verified and validated during the follow-up period.

Synthesis and anti-inflammatory activity evaluation of a novel series of 6-phenoxy-[1,2,4]triazolo[3,4-a]phthalazine-3-carboxamide derivatives.

The transcription factor nuclear factor-κB (NF-κB) controls many physiological processes including inflammation, immunity, and apoptosis. In this study, a novel series of 6-phenoxy-[1,2,4]triazolo[3,4-a]phthalazine-3-carboxamide derivatives were synthesized as potent anti-inflammatory agents, which acted on tumor necrosis factor (TNF-α) as inhibitors of NF-κB activation. We showed that compounds 6h (6-(2,4-dichlorophenoxy)-[1,2,4]triazolo[3,4-a]phthalazine-3-carboxamide) and 6i (6-(3-tolyloxy)-[1,2,4]triazolo[3,4-a]phthalazine-3-carboxamide) showed more prominent anti-inflammatory activity than other compounds, with similar activities as the reference drug dihydrotanshinone; compound 6i showed the lowest cellular toxicity among the tested compounds. In vivo evaluation of the anti-inflammatory activity showed that compound 6i exhibited excellent anti-inflammatory activity with 58.19% inhibition at 50mg/kg intraperitoneal (i.p.), with equal efficacy as the positive control indomethacin (100mg/kg i.p.; 59.21% inhibition).

Synthesis and Biological Evaluation of Novel Benzothiazole Derivatives as Potential Anticonvulsant Agents.

New benztriazoles with a mercapto-triazole and other heterocycle substituents were synthesized and evaluated for their anticonvulsant activity and neurotoxicity by using the maximal electroshock (MES), subcutaneous pentylenetetrazole (scPTZ), and rotarod neurotoxicity (TOX) tests. Among the compounds studied, compound 2-((1H-1,2,4-triazol-3-yl)thio)-N-(6-((3-fluorobenzyl) oxy)benzo[d]thiazol-2-yl)acetamide (5i) and 2-((1H-1,2,4-triazol-3-yl)thio)-N-(6-((4-fluorobenzyl)oxy) benzo[d] thiazol-2-yl)acetmide (5j) were the most potent, with an ED50 value of 50.8 mg/kg and 54.8 mg/kg in the MES test and 76.0 mg/kg and 52.8 mg/kg in the scPTZ seizures test, respectively. They also showed lower neurotoxicity and, therefore a higher protective index. In particular, compound 5j showed high protective index (PI) values of 8.96 in the MES test and 9.30 in the scPTZ test, which were better than those of the standard drugs used as positive controls in this study.

[Retinal vessel diameter variation analysis in diabetic patients].

OBJECTIVE: To explore the influence factors of retinal vascular changes in diabetes patients. METHODS: Case control study. One hundred and fifty-five type 2 diabetes patients were divided into NDR group (n=80) and DR group (n=70) according to the presence of diabetic retinopathy. Fundus photographs were taken after pupil dilated, the diameter of retinal arterioles and venules were measured between 1.0 PD and 1.5 PD. To analyze the relationship between retinal artery diameter, vein diameter and hypertension, diabetes duration, and DR stage. With retinal artery and vein diameter as the dependent variable, DR stage, hypertension, diabetes duration, insulin using time and age as independent variables, using step method, multiple linear regression was undergoing. RESULTS: The diameter of retinal vein in DR group and NDR group were (90.37+7.95) and (83.45±7.80) µm, the difference was statistically significant (t=5.446, P=0.000). Retinal vein diameter was positively correlated with DR stage and diabetes duration (r=0.377, 0.250; P=0.000, 0.002). DR stage (b=2.382, P=0.000) had a linear relationship with retinal vein diameter (R(2)=0.142, F=25.285). The regression equation was: retinal vein diameter =84.269+ 2.382 · DR stage. Retinal artery diameter was negatively correlated with DR stage, diabetes duration, and hypertension duration (r=-0.453, -0.343, -0.199. P=0.000, 0.000, 0.013). DR stage (b=-2.091, P=0.000) and age (b=-0.182, P=0.000) has a linear relationship with retinal artery diameter (R(2)=0.290, F=31.088). The regression equation was: retinal artery diameter =64.011-2.091·DR stage -0.182·age. CONCLUSIONS: With DR developed, retinal vein diameter increases, retinal artery diameter decreases in diabetic patients. The duration of diabetes mellitus and hypertension were not related to the diameter of retinal artery and vein.

Thinner changes of the retinal nerve fiber layer in patients with mild cognitive impairment and Alzheimer's disease.

BACKGROUND: Alzheimer's disease (AD) is the most common form of dementia and patients often have visual disorders. Mild cognitive impairment (MCI) is characterized by a memory deficit when compared with those of a similar age and education level which could indicate an earlier onset of AD. The aim of this study is to measure the changes of the retinal nerve fiber layer (RNFL) thickness of AD and MCI patients in comparison with the normal age controls. METHODS: The RNFL thickness was assessed using optical coherence tomography (OCT) in patients with MCI, AD (mild, moderate and severe) and the age matched controls. RESULTS: The thickness of RNFL in the superior quadrant and total mean values are gradually and significantly decreased from MCI to severe AD when compared to that in the controls. There is also a significant reduction of the retinal nerve fiber layer in the inferior quadrant in severe AD patients. CONCLUSIONS: Our data indicate that the retinal nerve fiber layer degeneration is paralleled with dementia progression. Owing to its non-invasive and cost effective nature, monitoring RNFL thickness may have a value in assessing disease progression and the efficacy of any treatments.

Synthesis and anticonvulsant activity evaluation of 7-alkoxy[1,2,4]triazolo[3,4-b]benzothiazol-3(2H)-ones.

A new series of 7-alkoxy[1,2,4]triazolo[3,4-b]benzothiazol-3(2H)-ones were synthesized and evaluated for their anticonvulsant activities. Among these compounds, 7-propoxy[1,2,4]triazolo[3,4-b]benzothiazol-3(2H)-one (4c) and 7-butoxy[1,2,4]triazolo[3,4-b]benzothiazol-3(2H)-one (4d) showed the highest activity against maximal electroshock (MES)-induced tonic extension [effective dose (ED)50 : 11.4 and 13.6 mg/kg, respectively]. It is worth mentioning that compound 4d showed especially low neurotoxicity, which led to a high protective index (PI >51). The orally anticonvulsant activity data of compound 4d further confirmed its efficacy, in an MES test, and its high safety with a PI value of 50.2. In addition, the potency of compound 4h against seizures induced by pentylenetetrazole, 3-mercaptopropionic acid, and bicuculline in the chemical-induced seizure tests suggested that compound 4d may exert its anticonvulsant activity through affecting the GABAergic system.

The effect of leizumab on serum vascular endothelial growth factor, IL-6, MCP-1 inflammatory factors in neovascular glaucoma.

This study aimed to assess Leizumab's effect on serum endothelial growth factor, interleukin-6 (IL-6), monocyte chemotactic protein-1 (MCP-1), and inflammatory factors in neovascular glaucoma patients. 80 eligible patients treated between January 2021 and April 2023 were enrolled, randomly divided into control and study groups. The control group underwent vitrectomy while the study group received preoperative intravitreal rituximab injection. Measurements included serum and aqueous humor VEGF/PEDF, IL-6/MCP-1 levels, postoperative rebleeding/retinal detachment, and visual acuity changes over 6 weeks. After surgery, patients showed reduced serum VEGF/PEDF levels (P < 0.05), with decreased VEGF and increased PEDF in aqueous humor (P < 0.05). The study group had lower VEGF and higher PEDF levels than the control (P < 0.05). Serum IL-6/MCP-1 levels reduced post-surgery, with the study group lower than control (P < 0.05). Intraocular rebleeding was lower in the study group (P < 0.05), while retinal detachment rates were similar (P > 0.05). Visual acuity differed significantly from week 1 to 6 post-surgery (P < 0.05), with higher acuity in the study group during weeks 1-4 (P < 0.05). Weeks 5-6 follow-up showed no significant difference (P > 0.05). Pre-vitrectomy ranibizumab injection effectively reduced bleeding, VEGF/PEDF levels, inflammatory factors, and improved visual recovery.

Biodegradable Cements for Bone Regeneration.

Bone cements such as polymethyl methacrylate and calcium phosphates have been widely used for the reconstruction of bone. Despite their remarkable clinical success, the low degradation rate of these materials hampers a broader clinical use. Matching the degradation rate of the materials with neo bone formation remains a challenge for bone-repairing materials. Moreover, questions such as the mechanism of degradation and how the composition of the materials contribute to the degradation property remain unanswered. Therefore, the review provides an overview of currently used biodegradable bone cements such as calcium phosphates (CaP), calcium sulfates and organic-inorganic composites. The possible degradation mechanism and clinical performance of the biodegradable cements are summarized. This paper reviews up-to-date research and applications of biodegradable cements, hoping to provide researchers in the field with inspirations and references.

Effect of low-intensity transcranial ultrasound stimulation on theta and gamma oscillations in the mouse hippocampal CA1.

Previous studies have demonstrated that low-intensity transcranial ultrasound stimulation (TUS) can eliminate hippocampal neural activity. However, until now, it has remained unclear how ultrasound modulates theta and gamma oscillations in the hippocampus under different behavioral states. In this study, we used ultrasound to stimulate the CA1 in mice in anesthesia, awake and running states, and we simultaneously recorded the local field potential of the stimulation location. We analyzed the power spectrum, phase-amplitude coupling (PAC) of theta and gamma oscillations, and their relationship with ultrasound intensity. The results showed that (i) TUS significantly enhanced the absolute power of theta and gamma oscillations under anesthesia and in the awake state. (ii) The PAC strength between theta and gamma oscillations is significantly enhanced under the anesthesia and awake states but is weakened under the running state with TUS. (iii) Under anesthesia, the relative power of theta decreases and that of gamma increases as ultrasound intensity increases, and the result under the awake state is opposite that under the anesthesia state. (iv) The PAC index between theta and gamma increases as ultrasound intensity increases under the anesthesia and awake states. The above results demonstrate that TUS can modulate theta and gamma oscillations in the CA1 and that the modulation effect depends on behavioral states. Our study provides guidance for the application of ultrasound in modulating hippocampal function.

Hematoma-like dynamic hydrogelation through natural glycopeptide molecular recognition for infected bone fracture repair.

Infected bone fractures remain a major clinical challenge for orthopedic surgeons. From a tissue regeneration perspective, biomaterial scaffolds with antibacterial and osteoinductive activities are highly desired, while advanced materials capable of mimicking the pathological microenvironment during the healing process of infected tissues remain an area deserving more research. Hematoma, the gel-like blood coagulum, plays an essential role in bone fracture repair because of its ability to serve as a dynamic and temporary scaffold with cytokines for both pathogen elimination and tissue healing. In light of this, we designed a dynamic hydrogel with hematoma-like antimicrobial or reparative performance for infected bone fracture repair in this study. The proposed dynamic hydrogel network was based on the reversible recognition of a natural glycopeptide antibiotic vancomycin (Van) and its target dipeptide D-Ala-D-Ala (AA), which could serve as a hematoma-like scaffold for obliterating bacteria in the fracture region and promoting bone repair by introducing an endogenous osteogenic peptide (OGP). In vivo experiments demonstrated that the hydrogel could rapidly eradicate bacteria, improve bone regeneration and restore the local inflammatory microenvironment. Together, findings from this study imply that the use of hematoma-like dynamic hydrogel could lead to a biomimetic revolution in surgical strategies against susceptible bone fractures.

3D-Printed lattice-inspired composites for bone reconstruction.

Mechanical performance is crucial for biomedical applications of scaffolds. In this study, the stress distribution of six lattice-inspired structures was investigated using finite element simulations, and scaffolds with pre-designed structures were prepared using selective laser sintering (SLS) technology. The results showed that scaffolds with face-centered cubic (FCC) structures exhibited the highest compressive strength. Moreover, scaffolds composed of polylactic acid/anhydrous calcium hydrogen phosphate (PLA/DCPA) showed good mechanical properties and bioactivity. An in vitro study showed that these scaffolds promoted cell proliferation significantly and showed excellent osteogenic performance. Composite scaffolds with FCC structures are promising for bone tissue engineering.