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1.
Am J Pathol ; 193(3): 296-312, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36509119

RESUMO

The intestines play a crucial role in the development of sepsis. The balance between autophagy and apoptosis in intestinal epithelial cells is dynamic and determines intestinal permeability. The present study focused on the potential role of autophagy in sepsis-induced intestinal barrier dysfunction and explored the mechanisms in vivo and in vitro. Excessive apoptosis in intestinal epithelia and a disrupted intestinal barrier were observed in septic mice. Promoting autophagy with rapamycin reduced intestinal epithelial apoptosis and restored intestinal barrier function, presenting as decreased serum diamine oxidase (DAO) and fluorescein isothiocyanate-dextran 40 (FD40) levels and increased expression of zonula occludens-1 (ZO-1) and Occludin. Polo-like kinase 1 (PLK1) knockdown in mice ameliorated intestinal epithelial apoptosis and the intestinal barrier during sepsis, whereas these effects were reduced with chloroquine and enhanced with rapamycin. PLK1 also promoted cell autophagy and improved lipopolysaccharide-induced apoptosis and high permeability in vitro. Moreover, PLK1 physically interacted with mammalian target of rapamycin (mTOR) and participated in reciprocal regulatory crosstalk in intestinal epithelial cells during sepsis. This study provides novel insight into the role of autophagy in sepsis-induced intestinal barrier dysfunction and indicates that the PLK1-mTOR axis may be a promising therapeutic target for sepsis.


Assuntos
Enteropatias , Sepse , Camundongos , Animais , Sirolimo/farmacologia , Sirolimo/metabolismo , Mucosa Intestinal/metabolismo , Enteropatias/metabolismo , Autofagia , Serina-Treonina Quinases TOR/metabolismo , Sepse/complicações , Sepse/metabolismo , Mamíferos , Quinase 1 Polo-Like
2.
J Dairy Sci ; 106(8): 5416-5432, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37296049

RESUMO

The objective of this study was to determine the effect of dietary supplementation of n-3 polyunsaturated fatty acids (PUFA) and n-6 PUFA on dry matter intake (DMI), energy balance, oxidative stress, and performance of transition cows. Forty-five multiparous Holstein dairy cows with similar parity, body weight (BW), body condition score (BCS), and milk yield were used in a completely randomized design during a 56-d experimental period including 28 d prepartum and 28 d postpartum. At 240 d of pregnancy, cows were randomly assigned to one of the 3 isoenergetic and isoprotein dietary treatments, including a control ration containing 1% hydrogenated fatty acid (CON), a ration with 8% extruded soybean (HN6, high n-6 PUFA source), and a ration with 3.5% extruded flaxseed (HN3; high n-3 PUFA source). The HN6 and HN3 diets had an n-6/n-3 ratio of 3.05:1 and 0.64:1 in prepartum cows and 8.16:1 and 1.59:1 in postpartum cows, respectively. During the prepartum period (3, 2, and 1 wk before calving), DMI, DMI per unit of BW, total net energy intake, and net energy balance were higher in the HN3 than in the CON and NH6 groups. During the postpartum period (2, 3, and 4 wk after calving), cows fed HN3 and HN6 diets both showed increasing DMI, DMI as a percentage of BW, and total net energy intake compared with those fed the CON diet. The BW of calves in the HN3 group was 12.91% higher than those in the CON group. Yield and nutrient composition of colostrum (first milking after calving) were not affected by HN6 or HN3 but milk yield from 1 to 4 wk of milking was significantly improved compared with CON. During the transition period, BW, BCS, and BCS changes were not affected. Cows fed the HN6 diet had a higher plasma NEFA concentration compared with the CON cows during the prepartum period. Feeding HN3 reduced the proportion of de novo fatty acids and increased the proportion of preformed long-chain fatty acids in regular milk. In addition, the n-3 PUFA-enriched diet reduced the n-6/n-3 PUFA ratio in milk. In conclusion, increasing the n-3 fatty acids concentration in the diet increased both DMI during the transition period and milk production after calving, and supplementing n-3 fatty acids was more effective in mitigating the net energy balance after calving.


Assuntos
Ácidos Graxos Ômega-3 , Leite , Gravidez , Feminino , Bovinos , Animais , Lactação , Dieta/veterinária , Período Pós-Parto , Ingestão de Energia , Peso Corporal , Ácidos Graxos , Estresse Oxidativo , Metabolismo Energético
3.
Int Orthop ; 47(2): 527-532, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36422704

RESUMO

PURPOSE: Both robots and navigation are effective strategies for optimizing screw placement, as compared to freehand placement. However, few studies have compared the accuracy and efficiency of these two techniques. Thus, the purpose of this study is to compare the accuracy and efficiency of robotic and navigation-assisted screw placement in the spinal vertebrae. METHODS: The 24 spine models were divided into a robot- and navigation-assisted groups according to the left and right sides of the pedicle. The C-arm transmits image data simultaneously to the robot and navigates using only one scan. After screw placement, the accuracy of the two techniques were compared using "angular deviation" and "Gertzbein and Robbins scale" in different segments (C1-7, T1-4, T5-8, T9-12, and L1-S1). In addition, operation times were compared between robot- and navigation-assisted groups. RESULTS: Robots and navigation systems can simultaneously assist in screw placement. The robot-assisted group had significantly less angular deviation than the navigation-assisted group from C1 to S1 (p < 0.001). At the C1-7 and T1-4 segments, the robot-assisted group had a higher rate of acceptable screws than the robot-assisted group. However, at the T5-8, T9-12, and L1-S1 segments, no significant difference was found in the incidence of acceptable screws between the two groups. Moreover, robot-assisted screw placement required less operative time than navigation (p < 0.05). CONCLUSION: The robot is more accurate and efficient than navigation in aiding screw placement. In addition, robots and navigation can be combined without increasing the number of fluoroscopic views.


Assuntos
Parafusos Pediculares , Procedimentos Cirúrgicos Robóticos , Robótica , Fusão Vertebral , Cirurgia Assistida por Computador , Humanos , Robótica/métodos , Procedimentos Cirúrgicos Robóticos/métodos , Coluna Vertebral/cirurgia , Cirurgia Assistida por Computador/métodos , Fusão Vertebral/métodos , Vértebras Lombares/cirurgia , Estudos Retrospectivos
4.
J Cell Mol Med ; 25(20): 9724-9739, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34514712

RESUMO

Sepsis and sepsis-induced skeletal muscle atrophy are common in patients in intensive care units with high mortality, while the mechanisms are controversial and complicated. In the present study, the atrophy of skeletal muscle was evaluated in sepsis mouse model as well as the apoptosis of muscle fibres. Sepsis induced atrophy of skeletal muscle and apoptosis of myofibres in vivo and in vitro. In cell-based in vitro experiments, lipopolysaccharide (LPS) stimulation also inhibited the proliferation of myoblasts. At the molecular level, the expression of polo-like kinase 1 (PLK1) and phosphorylated protein kinase B (p-AKT) was decreased. Overexpression of PLK1 partly rescued LPS-induced apoptosis, proliferation suppression and atrophy in C2C12 cells. Furthermore, inhibiting the AKT pathway deteriorated LPS-induced atrophy in PLK1-overexpressing C2C12 myotubes. PLK1 was found to participate in regulating apoptosis and E3 ubiquitin ligase activity in C2C12 cells. Taken together, these results indicate that sepsis induces skeletal muscle atrophy by promoting apoptosis of muscle fibres and inhibiting proliferation of myoblasts via regulation of the PLK1-AKT pathway. These findings enhance understanding of the mechanism of sepsis-induced skeletal muscle atrophy.


Assuntos
Apoptose , Proteínas de Ciclo Celular/metabolismo , Atrofia Muscular/etiologia , Atrofia Muscular/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Sepse/complicações , Animais , Biomarcadores , Linhagem Celular , Sobrevivência Celular , Modelos Animais de Doenças , Imuno-Histoquímica , Imunofenotipagem , Masculino , Camundongos , Modelos Biológicos , Atrofia Muscular/diagnóstico , Mioblastos/metabolismo , Mioblastos/patologia , RNA Interferente Pequeno , Transdução de Sinais , Ubiquitina-Proteína Ligases/metabolismo , Quinase 1 Polo-Like
5.
Med Sci Monit ; 27: e933204, 2021 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-34824191

RESUMO

BACKGROUND This biomechanics study of the lower limbs aimed to compare the use of the International Society of Biomechanics Six-Degrees-of-Freedom (ISB-6DOF) model and the conventional gait model (CGM), formerly known as the Helen Hayes model, in 20 male sprinters who habitually used the forefoot (FF) or rearfoot (RF) strike modes. MATERIAL AND METHODS We used a motion capture system to compare the difference in lower-extremity joint mechanics between sprinters' forefoot or rearfoot strike mode during unplanned sidestepping (UPSS). Twenty elite sprinters participated in a motion capture test under 2 models. Each of the 10 participants were classified as having a habitual forefoot strike mode or rearfoot strike mode during unplanned sidestepping. Joint mechanics and gait parameters were calculated according to the designed movement. RESULTS Comparison of the 2 models showed that the knee joint angles were inconsistent (P<0.05), highlighting the difficulty of the Helen Hayes model in anatomical recognition. The results of the 2 models show that during the unplanned sidestepping, the sprinter using the habitual rearfoot strike mode had a greater load through the knee joint (P<0.05). Sprinters who used the habitual forefoot strike mode experienced greater load through their ankle joints (P<0.05). CONCLUSIONS The findings from this biomechanics study showed that when compared with the ISB-6DoF model, the findings from the CGM were more reproducible for the evaluation of FF and RF strike during unplanned sidestepping.


Assuntos
Atletas , Fenômenos Biomecânicos/fisiologia , Marcha/fisiologia , Extremidade Inferior/fisiologia , Corrida/fisiologia , Adulto , China , Humanos , Masculino , Sociedades Médicas , Adulto Jovem
6.
Med Sci Monit ; 27: e930081, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33664219

RESUMO

BACKGROUND We analyzed the effect of limitation of movement of the first metatarsophalangeal joint (FMJ) on the biomechanics of the lower limbs during walking. MATERIAL AND METHODS Eight healthy college students completed walking under barefoot (BF) and FMJ constraint (FMJC) conditions. We synchronously collected kinematics and dynamics data, and calculated the torque, power, and work of hip, knee, and ankle joints. RESULTS Compared with normal conditions, when the FMJ is restricted from walking, the maximum ankle dorsiflexion angle is significantly increased (P<0.001), the maximum plantar flexion angle is significantly reduced (P<0.001), the maximum plantar flexion torque (P<0.001) and the maximum dorsiflexion torque (P<0.05) increased significantly, the maximum power increased significantly (P<0.001), the minimum power decreased significantly (P<0.001), and the negative work increased significantly (P<0.001). The torque of hip and knee joints increased significantly (P<0.05). CONCLUSIONS After the movement of the FMJ is restricted, the human body mainly compensates and transfers compensation by increasing the angle of dorsiflexion, increasing work and the activity level of surrounding muscles through the ankle joint, thereby increasing the torque load of the knee and hip joints to maintain the dynamic balance of kinematics. FMJC condition increases the energy consumption of the human ankle, knee, and hip joints during walking. The load is compensated by the gradual attenuation of the ankle, knee, and hip. Long-term limitation may cause damage to the posterior calf muscles and increase the incidence of knee arthritis.


Assuntos
Fenômenos Biomecânicos/fisiologia , Articulação Metatarsofalângica/fisiologia , Caminhada/fisiologia , Tornozelo , Articulação do Tornozelo/fisiologia , Eletromiografia/métodos , Feminino , Marcha/fisiologia , Articulação do Quadril/fisiologia , Humanos , Joelho , Articulação do Joelho/fisiologia , Perna (Membro)/fisiologia , Extremidade Inferior/fisiologia , Masculino , Movimento/fisiologia , Músculo Esquelético/fisiologia , Torque , Adulto Jovem
7.
Korean J Physiol Pharmacol ; 25(4): 375-383, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34187954

RESUMO

The intestinal barrier function disrupted in sepsis, while little is known about the variation in different phases of sepsis. In this study, mouse models of sepsis were established by caecal ligation and puncture (CLP). The H&E staining of sections and serum diamine oxidase concentration were evaluated at different timepoint after CLP. TUNEL assay and EdU staining were performed to evaluate the apoptosis and proliferation of intestinal epithelium. Relative protein expression was assessed by Western blotting and serum concentrations of pro-inflammatory cytokines was measured by ELISA. The disruption of intestinal barrier worsened in the first 24 h after the onset of sepsis and gradually recovered over the next 24 h. The percentage of apoptotic cell increased in the first 24 h and dropped at 48 h, accompanied with the proliferative rate of intestinal epithelium inhibited in the first 6 h and regained in the later period. Furthermore, the activity of nuclear factor kappa B (NF-κB) presented similar trend with the intestinal barrier function, shared positive correction with apoptosis of intestinal epithelium. These findings reveal the conversion process of intestinal barrier function in sepsis and this process is closely correlated with the activity of NF-κB signaling.

8.
Sensors (Basel) ; 20(10)2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32443543

RESUMO

In this paper, we propose an Si3N4/SiO2 horizontal-slot-waveguide-based polarization beam splitter (PBS) with low nonlinearity for on-chip high-power systems. The coupling length ratio between the quasi-TE and quasi-TM modes (LTE/LTM) was optimized to 2 for an efficient polarization splitting. For the single-slot design, the coupling length of the PBS was 281.5 µm, while the extinction ratios (ER) of the quasi-TM and quasi-TE modes were 23.9 dB and 20.8 dB, respectively. Compared to PBS based on the Si3N4 strip waveguide, the coupling length became 22.6% shorter. The proposed PBSs also had a relatively good fabrication tolerance for an ER of >20 dB. For the multi-slot design, the coupling length of the PBS was 290.3 µm, while the corresponding ER of the two polarizations were 24.0 dB and 21.0 dB, respectively. Furthermore, we investigated the tradeoff between the ER and coupling length for the optimized PBSs with single slot or multiple slots.

9.
Med Sci Monit ; 25: 1392-1400, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30789873

RESUMO

BACKGROUND Traditional ankle-foot orthoses (AFOs) are not effective in treating plantar fasciitis, while customized 3-dimensional (3D) printed ankle-foot orthoses are effective in treating many ankle-foot diseases. This study investigated the effects of customized 3D printed AFOs on biomechanics and comfort of the plantar foot in plantar fasciitis. MATERIAL AND METHODS Sixty patients with bilateral plantar fasciitis aged 31-60 years participated in this study. At week 0, patients were randomly assigned into 2 groups: the control group consisting of those wearing separate shoes with prefabricated AFOs; and the experimental group consisting of those wearing a separate shoe and customized 3D-printed AFO. The Footscan® system recorded maximum pressure, maximum strength, and contact area of patients' hallux, toes 2-5, first to fifth metatarsal, midfoot, lateral heel, and midfoot heel at weeks 0 and 8. Patients used visual analogue scale scores at weeks 0 and 8 to assess overall comfort of foot orthosis, to determine the credibility and comfort of both orthopedic insole conditions. RESULTS At week 0, in the experimental group, peak pressure in the hallux and first metatarsal area was significantly higher than the control group (P<0.05), while mid-heel and lateral heel peak pressures were significantly lower than the control group (P<0.05). After 8 weeks, all groups reported more comfort compared with the same group in week 0 (P<0.05). The comfort scores reported by the experimental group were significantly lower than those of the control group (P<0.05). CONCLUSIONS This study supports the efficiency of customized 3D printing AFO for reducing damage associated with plantar lesions and improving comfort in patients with plantar fasciitis compared with prefabricated AFO. Customized AFO is useful in the treatment of plantar fasciitis compared with prefabricated AFOs.


Assuntos
Fasciíte Plantar/terapia , Manejo da Dor/métodos , Adulto , Tornozelo , Desenho de Equipamento/instrumentação , Feminino , , Órtoses do Pé , Humanos , Masculino , Pessoa de Meia-Idade , Dor/reabilitação , Medição da Dor/métodos , Modelagem Computacional Específica para o Paciente , Pressão , Impressão Tridimensional/instrumentação , Sapatos
10.
Med Sci Monit ; 25: 3510-3519, 2019 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-31079137

RESUMO

BACKGROUND There are many shortcomings in traditional prefabricated rehabilitation insoles for symptomatic flatfoot patients. This study investigated the effects of customized 3-dimensional (3D) printed insoles on pressure and comfort of the plantar foot in symptomatic flatfoot patients. MATERIAL AND METHODS Eighty patients with bilateral flatfoot participated in this study. At week 0, patients were randomly assigned into 1 of 2 groups. In the control group, the patients wore standardize shoes with prefabricated insoles; and in the experimental group the patients wore standardize shoes and customized insoles. The Footscan® system recorded peak pressure, peak force, and peak contact area in 10 areas of the sole at weeks 0 and at week 8. Patients used visual analogue scale scores at week 0 and at week 8 to assess overall comfort of insoles. RESULTS At week 0, compared with the control group, the peak pressure in the metatarsal was significantly lower in the experimental group (P<0.05) while the peak pressure in the mid-foot was significantly higher than the control group (P<0.05). At week 8, in the experimental group, the peak pressures in the mid-foot were significantly higher than the control group (P<0.05). The comfort scores (measured by pain scale) reported by the experimental group were significantly lower than those reported by the control group (P<0.05). CONCLUSIONS Customized 3D printed insoles reduced the pressure on the metatarsals by distributed it over the mid-foot area, thus reduced the damage from symptomatic flatfoot. Customized 3D printed insoles were more effective than prefabricated insoles and offered better comfort for patients with symptomatic flatfoot.


Assuntos
Pé Chato/terapia , Órtoses do Pé/normas , Adulto , Desenho de Equipamento/métodos , Fadiga , Feminino , , Humanos , Masculino , Dor , Medição da Dor , Pressão , Impressão Tridimensional/instrumentação , Sapatos , Caminhada
11.
Mater Today Bio ; 24: 100896, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38162280

RESUMO

Mineralized collagen (MC) is the fundamental unit of natural bone tissue and can induce bone regeneration. Unmodified MC has poor mechanical properties and a single component, making it unable to cope with complex physiological environment. In this study, we introduced sodium alginate (SA) and vascular endothelial growth factor (VEGF) into the MC material to construct functionalized mineralized collagen (FMC) with good mechanical strength and the ability to continuously release growth factors. The FMC is filled into the pores of 3D printed titanium alloy scaffold to form a new organic-inorganic bioactive interface. With the continuous degradation of FMC, bone marrow mesenchymal stem cells (BMSCs) and vascular endothelial cells (VECs) in the surrounding environment are recruited to the surface of the scaffold to promote bone and vascular regeneration. After implanting the scaffold into the distal femoral defect of rabbits, Micro CT, histological, push-out, as well as immunohistochemical analysis showed that the composite interface can significantly promote osseointegration. These findings provide a new strategy for the development and application of mineralized collagen materials.

12.
Int J Surg ; 110(2): 921-933, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-37983808

RESUMO

INTRODUCTION: Spinal meningiomas (SMs) are relatively rare central nervous system tumors that usually trigger neurological symptoms. The prevalence of SMs is increasing with the aging of the global population. This study aimed to perform a systematic epidemiologic and survival prognostic analysis of SMs to evaluate their public health impact and to develop a novel method to estimate the overall survival at 3-year, 5-year, and 10-year in patients with SMs. METHODS: Five thousand one hundred fifty eight patients with SMs were recruited from the Surveillance, Epidemiology, and End Results (SEER) database from 2000 to 2019. Firstly, descriptive analysis was performed on the epidemiology of SMs. Secondly, these individuals were randomly allocated to the training and validation sets in a ratio of 7:3. Kaplan-Meier method and Cox regression analysis were utilized in the training set to identify independent prognostic factors and to construct a nomogram for survival prognosis. Subsequently, the discriminative power, predictive performance, and clinical utility of the nomogram were evaluated by receiver operating characteristic curve and decision curve analysis. Finally, a mortality risk stratification system and a web-based dynamic nomogram were constructed to quantify the risk of mortality in patients with SMs. RESULTS: The annual age-adjusted incidence rates of SMs increased steadily since 2004, reaching a rate of 0.40 cases per 100 000 population in 2019, with a female-to-male ratio of ~4:1. The age groups of 50-59, 60-69, and 70-79 years old were the most prevalent ages for SMs, accounting for 19.08, 24.93, and 23.32%, respectively. In addition, seven independent prognostic factors were identified to establish a prognostic nomogram for patients with SMs. The decision curve analysis and receiver operating characteristic curve indicated that the nomogram had high clinical utility and favorable accuracy. Moreover, the mortality risk stratification system effectively divided patients into low-risk, middle-risk, and high-risk subgroups. CONCLUSIONS: SMs are relatively rare benign spinal tumors prevalent in the white elderly female population. Clinicians could use the nomogram to personalize the prediction of the overall survival probability of patients with SMs, categorize these patients into different mortality risk subgroups, and develop personalized decision-making plans. Moreover, the web-based dynamic nomogram could help to further promote clinical application and assist clinicians in providing personalized counseling, timely monitoring, and clinical assessment for patients.


Assuntos
Neoplasias Meníngeas , Meningioma , Idoso , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Meningioma/epidemiologia , Estudos Retrospectivos , Nomogramas , Saúde Pública , Neoplasias Meníngeas/epidemiologia , Prognóstico , Programa de SEER
13.
Ecology ; 105(6): e4300, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38650396

RESUMO

Ongoing habitat loss and fragmentation caused by human activities represent one of the greatest causes of biodiversity loss. However, the effects of habitat loss and fragmentation are not felt equally among species. Here, we examined how habitat loss influenced the diversity and abundance of species from different trophic levels, with different traits, by taking advantage of an inadvertent experiment that created habitat islands from a once continuous forest via the creation of the Thousand Island Lake, a large reservoir in China. On 28 of these islands with more than a 9000-fold difference in their area (0.12-1154 ha), we sampled plants, herbivorous insects, and predatory insects using effort-controlled sampling and analyses. This allowed us to discern whether any observed differences in species diversity were due to passive sampling alone or to demographic effects that disproportionately influenced some species relative to others. We found that while most metrics of sampling effort-controlled diversity increased with island area, the strength of the effect was exacerbated for species in higher trophic levels. When we more explicitly examined differences in species composition among islands, we found that the pairwise difference in species composition among islands was dominated by species turnover but that nestedness increased with differences in island area, indicating that some species are more likely to be absent from smaller islands. Furthermore, by examining trends of several dispersal-related traits of species, we found that species with lower dispersal propensity tended to be those that were lost from smaller islands, which was observed for herbivorous and predatory insects. Our results emphasize the importance of incorporating within-patch demographic effects, as well as the taxa and traits of species when understanding the influence of habitat loss on biodiversity.


Assuntos
Biodiversidade , Ecossistema , Insetos , Ilhas , Animais , Insetos/fisiologia , China , Plantas/classificação , Cadeia Alimentar , Distribuição Animal , Conservação dos Recursos Naturais
14.
Int J Biol Macromol ; 259(Pt 2): 129073, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38184033

RESUMO

Fluid hydrogel is proper to be incorporated with rigid porous prosthesis interface, acting as a soft carrier to support cells and therapeutic factors, to enhance osseointegration. In the previous study, we innovatively utilized self-healing supramolecular hydrogel as 3D cell culture platform to incorporate with 3D printed porous titanium alloy scaffold, constructing a novel bioactive interface. However, the concrete relationship and mechanism of hydrogel stiffness influencing cellular behaviors of bone marrow mesenchymal stem cells (BMSCs) within the interface are still inconclusive. Herein, we synthesized a series of supramolecular hydrogels with variable stiffness as extracellular matrix (ECM) to enhance the osseointegration of 3D printed prosthesis interface. BMSCs exposed to stiff hydrogel received massive environmental mechanical stimulations, subsequently transducing biophysical cues into biochemical signal through mechanotransduction process. The mRNA-sequencing analysis revealed that the activated FAK-MAPK pathway played significant roles in promoting osteogenic differentiation, thus contributing to a strong osseointegration. Our work preliminarily demonstrated the relationship of ECM stiffness and osteogenic differentiation trend of BMSCs, and optimized stiffness of hydrogel within a certain range benefitting for osteogenic differentiation and prosthesis interface osseointegration, providing a valuable insight into the development of orthopaedic implants equipped with osteogenic mechanotransduction ability.


Assuntos
Hidrogéis , Células-Tronco Mesenquimais , Hidrogéis/química , Osteogênese , Osseointegração , Mecanotransdução Celular , Próteses e Implantes , Diferenciação Celular
15.
Surgery ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38762380

RESUMO

BACKGROUND: Sepsis, characterized by dysregulated host responses to infection, remains a critical global health concern, with high morbidity and mortality rates. The gastrointestinal tract assumes a pivotal role in sepsis due to its dual functionality as a protective barrier against injurious agents and as a regulator of motility. Dexmedetomidine, an α2-adrenergic agonist commonly employed in critical care settings, exhibits promise in influencing the maintenance of intestinal barrier integrity during sepsis. However, its impact on intestinal motility, a crucial component of intestinal function, remains incompletely understood. METHODS: In this study, we investigated dexmedetomidine's multifaceted effects on intestinal barrier function and motility during sepsis using both in vitro and in vivo models. Sepsis was induced in Sprague-Dawley rats via cecal ligation and puncture. Rats were treated with dexmedetomidine post-cecal ligation and puncture, and various parameters were assessed to elucidate dexmedetomidine's impact. RESULTS: Our findings revealed a dichotomous influence of dexmedetomidine on intestinal physiology. In septic rats, dexmedetomidine administration resulted in improved intestinal barrier integrity, as evidenced by reduced mucosal hyper-permeability and morphological alterations. However, a contrasting effect was observed on intestinal motility, as dexmedetomidine treatment inhibited both the frequency and amplitude of contractions in isolated intestinal strips and decreased the distance of ink migration in vivo. Additionally, dexmedetomidine suppressed the secretion of pro-motility hormones while having no influence on hormones that inhibit intestinal peristalsis. CONCLUSION: The study revealed that during sepsis, dexmedetomidine exhibited protective effects on barrier integrity, although concurrently it hindered intestinal motility, partly attributed to its modulation of pro-motility hormone secretion. These findings underscore the necessity of a comprehensive understanding of dexmedetomidine's impact on multiple facets of gastrointestinal physiology in sepsis management, offering potential implications for therapeutic strategies and patient care.

16.
Mater Today Bio ; 26: 101076, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38711938

RESUMO

Periprosthetic infection and mechanical loosening are two leading causes of implant failure in orthopedic surgery that have devastating consequences for patients both physically and financially. Hence, advanced prostheses to simultaneously prevent periprosthetic infection and promote osseointegration are highly desired to achieve long-term success in orthopedics. In this study, we proposed a multifunctional three-dimensional printed porous titanium alloy prosthesis coated with imidazolium ionic liquid. The imidazolium ionic liquid coating exhibited excellent bacterial recruitment property and near-infrared (NIR) triggered photothermal bactericidal activity, enabling the prosthesis to effectively trap bacteria in its vicinity and kill them remotely via tissue-penetrating NIR irradiation. In vivo anti-infection and osseointegration investigations in infected animal models confirmed that our antibacterial prosthesis could provide long-term and sustainable prevention against periprosthetic infection, while promoting osseointegration simultaneously. It is expected to accelerate the development of next-generation prostheses and improve patient outcomes after prosthesis implantation.

17.
Mater Today Bio ; 20: 100636, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37441138

RESUMO

Strontium (Sr) and strontium ranelate (SR) are commonly used therapeutic drugs for patients suffering from osteoporosis. Researches have showed that Sr can significantly improve the biological activity and physicochemical properties of materials in vitro and in vivo. Therefore, a large number of strontium containing biomaterials have been developed for repairing bone defects and promoting osseointegration. In this review, we provide a comprehensive overview of Sr-containing biomaterials along with the current state of their clinical use. For this purpose, the different types of biomaterials including calcium phosphate, bioactive glass, and polymers are discussed and provided future outlook on the fabrication of the next-generation multifunctional and smart biomaterials.

18.
J Control Release ; 363: 721-732, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37741462

RESUMO

The spine is the most common site of bone metastases, as 20%-40% of cancer patients suffer from spinal metastases. Treatments for spinal metastases are scarce and palliative, primarily aiming at relieving bone pain and preserving neurological function. The bioactive agents-mediated therapies are the most effective modalities for treating spinal metastases because they achieve systematic and specific tumor regression. However, the clinical applications of some bioactive agents are limited due to the lack of targeting capabilities, severe side effects, and vulnerability of drug resistance. Fortunately, advanced biomaterials have been developed as excipients to enhance these treatments, including chemotherapy, phototherapy, magnetic hyperthermia therapy, and combination therapy, by improving tumor targeting and enabling sustaining and stimuli-responsive release of various therapeutic agents. Herein, the review summarizes the development of biomaterials-mediated bioactive agents for enhanced treatments of spinal metastases and predicts future research trends.


Assuntos
Neoplasias da Coluna Vertebral , Humanos , Neoplasias da Coluna Vertebral/tratamento farmacológico , Neoplasias da Coluna Vertebral/secundário , Materiais Biocompatíveis/uso terapêutico , Fototerapia
19.
Sci Rep ; 13(1): 15945, 2023 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-37743441

RESUMO

In a solid-state photonics-based Lidar, all essential components can be integrated into a silicon chip. It is simple and effective to use a tunable laser source to implement Lidar's beam steering. However, how to effectively increase the steering angle in a small wavelength tuning range is usually a key challenge due to the limited material and waveguide dispersion. In Silicon-on-insulator waveguide, we design a novel solid-state Lidar using two trans-electrical (TE) polarized beams counter-propagating towards each other. Two corresponding output beams from just a single grating coupler (GC) can be seamlessly combined to double the beam steering angle. Furthermore, a low-priced solid-state Lidar is designed for TE polarized beams counter-propagating towards each other by using wavelength division multiplexed laser array.

20.
Global Spine J ; : 21925682231191094, 2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37498194

RESUMO

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: Spinal cord astrocytoma (SCA) is a rare central nervous system malignancy that typically requires early surgical intervention. However, the substantial frequency of relapse and bad outcomes limit the surgical advantage for patients. Herein, we aimed to determine the independent prognostic factors of cancer-specific survival (CSS) in post-surgical patients with primary SCA and to develop a new method to estimate the chances of CSS in these patients at 3-, 5- and 10-year. METHODS: A total of 364 postoperative patients with SCA were recruited from the Surveillance, Epidemiology, and End Results database and randomly assigned to the training and validation sets. Univariate and multivariate Cox regression assessments were used to identify independent prognostic indicators. Second, a nomogram was established by integrating these indicators to estimate 3-, 5-, and 10-year CSS in patients with SCA who underwent surgery. Subsequently, the discriminatory power and predictive performance of the nomogram were assessed using the receiver operating characteristic (ROC) curve, calibration curves, and decision curve analysis (DCA). Finally, a mortality risk stratification system was generated. RESULTS: Age, tumor stage, histological type, and radiotherapy were recognized as potential predictive indicators of CSS for postoperative patients with SCA. The ROC curve and DCA indicate that the nomogram has good accuracy and high clinical utility. Furthermore, the mortality risk stratification system efficiently divides patients into 3 risk subgroups. CONCLUSIONS: The nomogram could accurately anticipate the 3-, 5-, and 10-year percentages of CSS in postoperative patients with SCA. It could assist clinicians with personalized medical counseling, risk stratification management, and clinical decision-making, improving the clinical outcomes of these patients.

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