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1.
Front Pediatr ; 12: 1332020, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38813546

RESUMO

Objective: The study aims to analyze the clinical characteristics of acute phase of SARS-CoV-2 infection in children aged 0-17 years with the Omicron variant, and summarize the persistent symptoms or new-onset clinical manifestations from 4 to 12 weeks after acute COVID. Explore the association between the vaccination status and SARS-CoV-2 neutralizing antibody levels post infection among preschool-aged children. The comprehensive study systematically describes the clinical characteristics of children infected with SARS-CoV-2, providing a foundation for diagnosis and evaluating long-term COVID in pediatric populations. Methods: The study enrolled children who were referred to the Children's Hospital, Capital Institute of Pediatrics, (Beijing, China) from January 10, 2023 to March 31, 2023. Participants were classified as infant and toddlers, preschool, school-age, and adolescent groups. Children or their legal guardians completed survey questionnaires to provide information of previous SARS-CoV-2 infection history, as well as clinical presentation during the acute phase and long-term symptoms from 4 to 12 weeks following infection. Furthermore, serum samples were collected from children with confirmed history of SARS-CoV-2 infection for serological testing of neutralizing antibodies. Results: The study recruited a total of 2,001 children aged 0-17 years who had previously tested positive for SARS-CoV-2 through nucleic acid or antigen testing. Fever emerged as the predominant clinical manifestation in 1,902 (95.1%) individuals with body temperature ranging from 37.3 to 40.0°C. Respiratory symptoms were identified as secondary clinical manifestations, with cough being the most common symptom in 777 (38.8%) children, followed by sore throat (22.1%), nasal congestion (17.8%), and runnning nose (17.2%). Fatigue (21.6%), headache (19.8%) and muscle-joint pain (13.5%) were frequently reported systemic symptoms in children. The proportion of children with symptoms of SARS-CoV-2 infection varied across age groups. 1,100 (55.0%) children experienced persistent symptoms from 4 to 12 weeks post the acute phase of infection. Trouble concentrating (22.1%), cough (22.1%), and fatigue (12.1%) were frequently reported across age groups in the extended period. A limited number of children exhibited cardiovascular symptoms with chest tightness, tachycardia, and chest pain reported by 3.5%, 2.5%, and 1.8% of children, respectively. Among 472 children aged 3-5 years, 208 children had received two doses of SARS-CoV-2 vaccine at least 6 months prior to infection, and no association was found between the incidence of long-term COVID and pre-infection vaccination statuses among the 3-5 years age groups (χ2 = 1.136, P = 0.286). Conclusions: In children aged 0-17 years infected with SARS-CoV-2 Omicron variant, fever was the primary clinical manifestation in the acute phase, followed by respiratory symptoms, systemic non-specific and digestive presentations. In particular, respiratory and digestive system symptoms were more frequent in children aged above 6 years. Regarding the long-term symptoms from 4 to 12 weeks post-infection, the most common presentations were concentrating difficulty, cough, and fatigue. The incidence of persistent symptoms of SARS-CoV-2 did not exhibit a significant correlation with vaccination status, which was attributed to the waning efficacy of the vaccine-induced humoral immune response after 6 months.

2.
Arthrosc Tech ; 13(4): 102904, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38690354

RESUMO

Arthroscopic repair of Bankart injury is the first choice for the treatment of anterior shoulder instability. How to avoid recurring shoulder joint dislocation is a challenge, especially when combined with Hill-Sachs lesions. The arthroscopy technology allows for broader vision and less surgical trauma but is limited by a smaller operating space. At present, extensive descriptions about the surgical procedure of arthroscopic Bankart repair have been published. In this Technical Note, we describe the use of remplissage filling with Hill-Sachs lesion combined with Bankart repair to further improve the surgical accuracy and clinical efficacy. In particular, the application of single needle-assisted outside-in remplissage technique and Bankart repair is introduced in detail.

3.
ACS Omega ; 9(20): 21983-21993, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38799320

RESUMO

Self-excited combustion instability in an annular combustor with low-swirl flames is studied with a combination of large eddy simulation (LES) and acoustic solvers. Acoustic analysis with a Helmholtz solver provides an estimate of frequencies and modal structures in the annular combustor. LES gives detailed modal dynamics for specific instability modes. Combustion instabilities in the annular combustor including longitudinal, spinning, and standing modes are successfully captured in a single LES. Numerical results show that the instability modes are not constant; they switch among these modes randomly and rapidly. The flow oscillates back and forth in phase with the largest pressure amplitude located near the outlet of the injectors for the longitudinal mode. The azimuthal instability oscillates in the 1A2L mode of the annular system. In the spinning mode, the pressure antinodes move forward while the modal structure keeps constant. For the standing mode, the locations of pressure antinodes are fixed in the annular combustor and the fluctuations at the pressure antinodes keep out of phase. The near-zero value of the mean spin ratio indicates that the dominant azimuthal mode is the standing mode. The azimuthal modes captured by LES are in good agreement with that predicted by Helmholtz solver in terms of frequency and modal structure. The maximum deviation of the predicted frequency is less than 5%. This adds values before the low-swirl injector is placed into the actual annular combustor.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38657168

RESUMO

Modulating the electrical properties of two-dimensional (2D) materials is a fundamental prerequisite for their development to advanced electronic and optoelectronic devices. Substitutional doping has been demonstrated as an effective method for tuning the band structure in monolayer 2D materials. Here, we demonstrate a facile selective-area growth of vanadium-doped molybdenum disulfide (V-doped MoS2) flakes via pre-patterned vanadium-metal-assisted chemical vapor deposition (CVD). Optical microscopy characterization revealed the presence of flake arrays. Transmission electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy were employed to identify the chemical composition and crystalline structure of as-grown flakes. Electrical measurements indicated a light p-type conduction behavior in monolayer V-doped MoS2. Furthermore, the response time of phototransistors based on V-doped MoS2 monolayers exhibited a remarkable capability of 3 ms, representing approximately 3 orders of magnitude faster response than that observed in pure MoS2 phototransistors. This work hereby provides a feasible approach to doping of 2D materials, promising a scalable pathway for the integration of these materials into emerging electronic and optoelectronic devices.

5.
Int J Surg ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38549227

RESUMO

BACKGROUND: There was controversy surrounding the optimal thromboprophylaxis strategy for COVID-19 patients. This included debates on the dosage of anticoagulants for thromboembolism prophylaxis, the requirement for additional antiplatelet therapy, and the necessity of prophylaxis for outpatients and post-discharge. To explore this, we performed a meta-analysis of randomized controlled trials. METHODS: PubMed, Cochrane Library, Embase, and Web of Science were last searched on 26 July 2023 for studies comparing the effect of different dose of anticoagulation, additional antiplatelet and post-discharge prophylaxis for COVID-19 patients. The results of eligible studies were analyzed in terms of thromboembolism events, major bleeding and all-cause mortality during follow-up. RESULTS: Our study included a total of 25 randomized controlled trials, involving 17,911 patients. Our results revealed that, compared to prophylactic dose, therapeutic dose showed lower thrombotic risk (RR, 0.66; 95%CI, 0.45 to 0.96) but had similar major bleeding risk for critically ill patients with COVID-19. On the other hand, intermediate dose and prophylactic dose demonstrated similar thromboembolism risk and major bleeding risk. For non-critically ill patients with COVID-19, therapeutic dose of anticoagulants was associated with lower thrombotic risk (RR, 0.50; 95%CI 0.34 to 0.72) but, at the same time, increased the risk of major bleeding (RR, 2.01; 95%CI 1.22 to 3.33). However, intermediate dose showed lower thromboembolism risk (RR, 0.38; 95%CI 0.21 to 0.69) while maintaining a similar major bleeding risk. In critically ill patients, additional antiplatelet therapy showed similar thromboembolism, major bleeding risk, and mortality when compared to no treatment. For outpatients, additional prophylactic anticoagulation showed similar thromboembolism, major bleeding risk, and mortality when compared to no treatment. For post-discharge patients, post-discharge prophylaxis reduced thromboembolism risk (RR, 0.49; 95%CI 0.31 to 0.76) but increased major bleeding risk (RR, 2.63; 95%CI, 1.13 to 6.14). CONCLUSION: For non-critically ill patients, therapeutic dose prophylactic anticoagulation significantly reduced venous thromboembolism but increases major bleeding risk. Intermediate dose effectively lowered venous thromboembolism without raising major bleeding risk. The optimal dose and need for additional antiplatelet therapy in critically ill patients, as well as the necessity of prophylactic anticoagulation in outpatient and post-discharge patients, required further investigation and confirmation through rigorous evidence studies.

6.
Asian J Surg ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38531739

RESUMO

To compared the arthroscopic capsular release (ACR) with manipulation under anaesthesia (MUA) for the surgical treatment of frozen shoulder (FS) based on postoperative outcomes and complications. PubMed, Cochrane Library, Embase, and Web of Science were searched on October 2, 2023 to retrieve eligible studies that compared ACR with MUA in terms of clinical outcomes (pain visual analogue scale, external rotation, forward flexion and adverse events) for patients with FS. Mean differences (MD) were calculated for continuous outcomes and odds ratios (OR) were calculated for dichotomous outcomes. Six papers, including 5 clinical studies (a total of 690 shoulders), were included in the final meta-analysis. The forward flexion was found to be larger in the ACR group at 3 months (MD, 2.73; 95%CI, 0.42-5.04; I2 = 44%; P = 0.02) and 6 months (MD, 2.36; 95%CI, 1.29-3.44; I2 = 0%; P < 0.0001). Except for this, ACR was comparable with MUA in terms of pain visual analogue scale at 3, 6 and 12 months (p = 0.25, p = 0.11, p = 0.28, respectively), external rotation at 3, 6 and 12 months (p = 0.15, p = 0.52, p = 0.23, respectively), and forward flexion at 12 months (p = 0.08). There were no differences in complication rates between the two groups (OR, 0.82; 95%CI, 0.47-1.44; I2 = 0%; P = 0.50). In comparison with MUA, ACR demonstrated better outcomes for forward flexion at 3 and 6 months, while there were no significant differences between ACR and MUA in terms of pain visual analogue scale, external rotation and adverse events.

7.
Asian J Surg ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38531745

RESUMO

BACKGROUND: Degenerative meniscal tear (DMT) is common in the elderly population. However, there has been controversy over the treatment of DMT regarding whether to adopt arthroscopic partial meniscectomy (APM) or exercise therapy (ET). In order to compare the long-term outcomes between the two treatment methods, we conducted a meta-analysis of randomized controlled trials (RCTs) with long-term follow-up. METHODS: PubMed, Cochrane Library, Embase, and Web of Science were last searched on 16 April 2023 for studies on DMT that compared the clinical outcomes between APM and ET. The subjective outcomes of the comparison include the Knee Injury and Osteoarthritis Outcome Score (KOOS), which consists of five sub-scales: pain, symptoms, activities of daily living (ADL), sport and recreation (Sport/recreation), and quality of life (QOL). The objective outcome includes knee osteoarthritis progression. RESULTS: We identified 6 potentially eligible trials, including 1078 participants, from the literature search. ET showed a lower risk of knee osteoarthritis progression than APM (RR, 1·27; 95%CI 1·05 to 1·53). There were no statistically significant differences in the KOOS-pain, KOOS-symptoms, KOOS-ADL, KOOS-Sport/recreation, and KOOS-QOL between the two treatment methods. CONCLUSION: For the treatment of DMT, ET showed a lower risk of knee osteoarthritis progression than APM. ET and APM had comparable effects on subjective outcomes including pain management and knee function. Therefore, it is not recommended to use APM but rather recommended to use ET for treating APM.

8.
Small ; : e2400593, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38529744

RESUMO

As a kind of flexible electronic device, flexible pressure sensor has attracted wide attention in medical monitoring and human-machine interaction. With the continuous deepening of research, high-sensitivity sensor is developing from single function to multi-function. However, Current multifunctional sensors lack the ability to integrate joule heating, detect sliding friction, and self-healing. Herein, a MXene/polyurethane (PU) flexible pressure sensor with a self-healing property for joule heating and friction sliding is fabricated. The MXene/PU sensitive layer with special spinosum structure is prepared by a simple spraying method. After face-to-face assembly of the sensitive layers, the MXene/PU flexible pressure sensor is obtained and showed excellent sensitivity (150.65 kPa-1), fast response/recovery speed (75.5/63.9 ms), and good stability (10 000 cycles). Based on the self-healing property of PU, the sensor also has the ability to heal after mechanical damage. In addition, the sensor realizes the joule heating function under low voltage, and has the real-time monitoring ability of sliding objects. Combined with low cost and simple manufacturing method, the multi-functional MXene/PU flexible sensor shows a wide range of application potential in human activity monitoring, thermal management, and slip recognition.

9.
Arthrosc Tech ; 13(1): 102822, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38312872

RESUMO

Massive rotator cuff tears are a huge challenge for orthopaedic surgeons, as the patients may be in need of multiple operations, even including reverse total shoulder arthroplasty. The various repair methods for the rotator cuff, such as partial rotator cuff repair, patch-augmented rotator cuff repair, bridging rotator cuff reconstruction with graft interposition, tendon transfer, and superior capsular reconstruction, have always been the focus of research. During surgical intervention for failed rotator cuff repairs, complexity of tears, poor tissue quality, retained hardware, and adhesions are the problems routinely encountered. In this Technical Note, we describe the technique of interposition grafting using fascia lata autograft to reconstruct the rotator cuff after failed primary repair.

10.
Opt Lett ; 49(4): 1061-1064, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38359253

RESUMO

We demonstrated an AlGaN-based multiple-quantum-well (MQW) deep ultraviolet (DUV) laser at 278 nm using a nanoporous (NP) n-AlGaN as the bottom cladding layer grown on the sapphire substrate. The laser has a very-low-threshold optically pumped power density of 79 kW/cm2 at room temperature and a transverse electric (TE)-polarization-dominant emission. The high optical confinement factor of 9.12% benefiting from the low refractive index of the nanoporous n-AlGaN is the key to enable a low-threshold lasing. The I-V electrical measurement demonstrates that an ohmic contact can be still achieved in the NP n-AlGaN with a larger but acceptable resistance, which indicates it is compatible with electrically driven laser devices. Our work provides insights into the design and fabrication of low-threshold lasers emitting in the DUV regime.

11.
Medicine (Baltimore) ; 103(7): e36482, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363894

RESUMO

The purpose of this study was to reveal the current trends and preferences of Chinese orthopedic surgeons regarding anterior cruciate ligament (ACL) reconstruction through a nationwide web-based survey conducted in China. The survey questionnaire was distributed via WeChat to the chairmen of provincial orthopedic and sports medicine organizing committees in China, who then shared it in their respective WeChat workgroups. The questionnaire consisted of 52 multiple-choice questions covering 8 sections. Data collection was implemented by Questionnaire Star. A total of 812 valid questionnaires were returned: 94.21% of the respondents preferred single-bundle reconstruction of ACL, while 61.70% preferred autogenous semitendinosus plus gracilis reconstruction; 76.35% of the respondents preferred establishing the femoral tunnel first, while 47.29% preferred establishing the femoral tunnel through a medial auxiliary approach; and 85.10% of the respondents recommended patients to undergo surgery within 3 months after ligament injury. Besides, the vast majority of respondents chose to retain the ligamentous remnant bundle (92.98%) and recommended routine use of knee braces postoperatively (94.09%). It is recommended to perform arthroscopic single-bundle ACL reconstruction with the remnant preserving technique using a hamstring autograft within 3 months of ACL rupture, with support of postoperative functional braces.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Cirurgiões Ortopédicos , Humanos , Ligamento Cruzado Anterior/cirurgia , Lesões do Ligamento Cruzado Anterior/cirurgia , Inquéritos e Questionários , Reconstrução do Ligamento Cruzado Anterior/métodos
12.
Nat Commun ; 15(1): 946, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38297005

RESUMO

Parity-time (PT) symmetry has been unveiling new photonic regimes in non-Hermitian systems, with opportunities for lasing, sensing and enhanced light-matter interactions. The most exotic responses emerge at the exceptional point (EP) and in the broken PT-symmetry phase, yet in conventional PT-symmetric systems these regimes require large levels of gain and loss, posing remarkable challenges in practical settings. Floquet PT-symmetry, which may be realized by periodically flipping the effective gain/loss distribution in time, can relax these requirements and tailor the EP and PT-symmetry phases through the modulation period. Here, we explore Floquet PT-symmetry in an integrated photonic waveguide platform, in which the role of time is replaced by the propagation direction. We experimentally demonstrate spontaneous PT-symmetry breaking at small gain/loss levels and efficient control of amplification and suppression through the excitation ports. Our work introduces the advantages of Floquet PT-symmetry in a practical integrated photonic setting, enabling a powerful platform to observe PT-symmetric phenomena and leverage their extreme features, with applications in nanophotonics, coherent control of nanoscale light amplification and routing.

13.
J Control Release ; 367: 316-326, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38253202

RESUMO

A bioreducible Zn (II)-adenine multifunctional module (BS) and Tet1 peptide were used to modify low-molecular-weight PEI3.5k (polyethyleneimine with molecular weight of 3.5 kDa)into a siRNA vector Zn-PB-T with high transfection efficiency in neurons. A GSH-responsive breakable disulfide spacer was introduced into BS to realize the controlled release of siRNA from the polyplexes in cytoplasm. Zn-PB showed >90% transfection rates in multiple cell lines (3 T3, HK-2, HepG2, 293 T, HeLa, PANC-1),and 1.8-folds higher EGFP knockdown rates than commercial Lipo2k in normal cell line 293 T and cancer cell line HepG2. And Zn-PB-T1 showed 4.7-4.9- and 8.0-8.1-folds higher transfection efficiency comparing to commercial Lipo2k and PEI25k (polyethyleneimine with molecular weight of 25 kDa) in PC12 cells respectively, 2.1-fold EGFP gene silencing efficiency (96.6% EGFP knockdown rates) superior to commercial Lipo2k in neurons. In Parkinson's model, Zn-PB-T1/SNCA-siRNA can effectively protect neurons against MPP+-induced cell death and apoptosis, increasing the cell survival rate to 84.6% and reducing the cell apoptosis rate to 10.8%. This work demonstrated the promising application prospects of the resulting efficient siRNA carriers in siRNA-mediated gene therapy of Parkinson's disease.


Assuntos
Doença de Parkinson , Polieletrólitos , Ratos , Animais , Humanos , RNA Interferente Pequeno/química , Doença de Parkinson/genética , Doença de Parkinson/terapia , Polietilenoimina/química , Zinco , Transfecção , Células HeLa , Peptídeos
14.
J Control Release ; 366: 366-374, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38184231

RESUMO

A highly efficient siRNA vector (Zn-PQD) capable of selectively silencing genes in cancer cells was obtained by using ROS-cleavable DED to crosslink low molecular weight (LMW) polyethylene imine (PEI) modified by self-fluorescent metal coordinatied multifunctional module Zn-QS. Under the combined action of DED cross-linking and Zn-QS modification, Zn-PQD performs well in the siRNA delivery process in cancer cells, including siRNA condensation, cell uptake, endosome escape, and siRNA release. Zn-PQD exhibited higher transfection efficiency than commercial PEI25k and Lipo2k in multiple cancer cell lines including HepG2, HeLa, 4 T1, H520 and PANC-1, as well as cancer treatment-related stem cell rADSC. Ultimately, Zn-PQD can achieve extremely high and selective gene silencing effects in cancer cells (with a gene silencing rate of 98.3% in HepG2). This work is expected to provide an efficient and safe siRNA carrier for the future tumor siRNA therapy and its study of fluorescence mediated mechanism.


Assuntos
Neoplasias , Quinolinas , Humanos , RNA Interferente Pequeno , Espécies Reativas de Oxigênio/metabolismo , Zinco , Inativação Gênica , Polietilenoimina , Células HeLa , Neoplasias/genética
15.
Cytokine ; 174: 156459, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38056250

RESUMO

An increasing number of studies have shown that Nonalcoholic fatty liver disease (NAFLD) is strongly associated with obesity, insulin resistance, dyslipidemia, hypertension and metabolic syndrome, but its specific pathogenesis remains unclear. By analyzing GEO database, we found CXCL6 was upregulated in liver tissues of patients with NAFLD. We also confirmed with qPCR that CXCL6 is highly expressed in serum of patients with NAFLD. To identify the underlying impact of CXCL6 on NAFLD, we established animal and cell models of NAFLD. Similarly, we confirmed by qPCR and Western blot that CXCL6 was upregulated in the NAFLD model in vitro and vivo. After transfecting NAFLD cells with siRNA targeting CXCL6 (si-CXCL6), a series of functional experiments were carried out, and these data indicated that the inhibition of CXCL6 reduced intracellular lipid deposition, decreased AST, ALT and TG level, facilitate cell proliferation and suppress their apoptosis. Furthermore, western blot and qPCR analyses displayed that the suppression of CXCL6 could raise the PPARα expression, but PPAR α inhibitor, GW6471 could partially counteract this effect. What's more, Oil Red O staining, biochemical analyzer and TG detection kit revealed that GW6471 could reverse the inhibitory effect of si-CXCL6 on NAFLD. In summary, we provide convincing evidence that CXCL6 is markedly elevated in NAFLD, and the CXCL6/PPARα regulatory network mediates disease progression of NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Animais , Humanos , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , PPAR alfa/genética , Fígado/metabolismo , Obesidade/metabolismo , RNA Interferente Pequeno/metabolismo , Metabolismo dos Lipídeos , Quimiocina CXCL6/metabolismo
16.
An Acad Bras Cienc ; 95(suppl 2): e20230480, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38088732

RESUMO

LncRNAs are known to be key regulators in the initiation and development of diverse cancers. Whether LINC00115 is involved in the regulation of gastric cancer (GC) progression remains unclear. Here, we aimed to show the function of LINC00115 in GC. RT-qPCR was used to measure gene expression in GC tissues and cells. Colony formation, EdU, TUNEL, and wound healing assays were used to analyze cellular processes in GC. The in vivo GC xenograft model was established. We observed that LINC00115 was highly expressed in GC. Functionally, silencing LINC00115 inhibited GC cell proliferation, and migration but facilitated GC apoptosis. Mechanistically, LINC00115 sponged miR-212-5p, while miR-212-5p targeted ATPAF1 in GC cells. Rescue assays showed ATPAF1 overexpression countervailed the inhibitory role of LINC00115 depletion in GC progression in vitro and in vivo. Overall, LINC00115 promoted GC progression by upregulating ATPAF1 via miR-212-5p.


Assuntos
MicroRNAs , Neoplasias Gástricas , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética
17.
Opt Lett ; 48(23): 6312-6315, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38039255

RESUMO

We demonstrate the first, to the best of our knowledge, experimental observation of higher-order topological corner states in the photonic two-dimensional (2D) trimer lattices. Using a femtosecond laser direct writing technology, we experimentally fabricate a series of 2D trimer lattices with different open boundary conditions and thereby observe two kinds of 0D topological corner states, i.e., topological corner states and topological defect corner states. Interestingly, these corner states and defect corner states can not only exist in the bandgap but also coexist with the bulk states and show obvious localization properties. This work provides fresh perspectives on higher-order topology in artificial microstructures.

18.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(12): 1514-1522, 2023 Dec 15.
Artigo em Chinês | MEDLINE | ID: mdl-38130196

RESUMO

Objective: To investigate the feasibility of a dual-crosslinked injectable hydrogel derived from acellular musclar matrix (AMM) for promoting myoblasts proliferation and myogenic differentiation. Methods: Firstly, hyaluronic acid was oxidized with NaIO 4 and methylated to prepare methacrylamidated oxidized hyaluronic acid (MOHA). Then, AMM obtained by washing enzymatically treated muscle tissue was aminolyzed to prepare aminated AMM (AAMM). MOHA hydrogel and AAMM were crosslinked using Schiff based reaction and UV radiation to prepare a dual-crosslinked MOHA/AAMM injectable hydrogel. Fourier transform infrared spectroscopy (FTIR) was used to characterize MOHA, AAMM, and MOHA/AAMM hydrogels. The injectability of MOHA/AAMM hydrogel were evaluated by manual injection, and the gelation performance was assessed by UV crosslinking. The rheological properties and Young's modulus of the hydrogel were examined through mechanical tests. The degradation rate of the hydrogel was assessed by immersing it in PBS. The active components of the hydrogel were verified using immunofluorescence staining and ELISA assay kits. The promotion of cell proliferation by the hydrogel was tested using live/dead staining and cell counting kit 8 (CCK-8) assays after co-culturing with C2C12 myoblasts for 9 days. The effect of the hydrogel on myogenic differentiation was evaluated by immunofluorescence staining and real time quantitative polymerase chain reaction (RT-qPCR). Results: FTIR spectra confirmed the successful preparation of MOHA/AAMM hydrogel. The hydrogel exhibited good injectability and gelation ability. Compared to MOHA hydrogel, MOHA/AAMM hydrogel exhibited higher viscosity and Young's modulus, a reduced degradation rate, and contained a higher amount of collagen (including collagen type Ⅰ and collagen type Ⅲ) as well as bioactive factors (including epidermal growth factor, fibroblast growth factor 2, vascular endothelial growth factor, and insulin-like growth factor 1). The live/dead cell staining and CCK-8 assay indicated that with prolonged incubation time, there was a significant increase in viable cells and a decrease in dead cells in the C2C12 myoblasts within the MOHA/AAMM hydrogel. Compared with MOHA hydrogel, the difference was significant at each time point ( P<0.05). Immunofluorescence staining and RT-qPCR analysis demonstrated that the deposition of IGF-1 and expression levels of myogenic-related genes (including Myogenin, Troponin T, and myosin heavy chain) in the MOHA/AAMM group were significantly higher than those in the MOHA group ( P<0.05). Conclusion: The MOHA/AAMM hydrogel prepared based on AMM can promote myoblasts proliferation and myogenic differentiation, providing a novel dual-crosslinked injectable hydrogel for muscle tissue engineering.


Assuntos
Ácido Hialurônico , Hidrogéis , Ácido Hialurônico/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Engenharia Tecidual/métodos , Diferenciação Celular , Mioblastos/metabolismo , Proliferação de Células
19.
Medicine (Baltimore) ; 102(50): e36626, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38115261

RESUMO

RATIONALE: Myxofibrosarcoma most commonly arises as a slowly enlarging, painless mass. We describe an unusual case of low-grade myxofibrosarcoma in the axillary fossa, which infiltrated the brachial plexus, axillary artery, and axillary vein, causing severe pain. The low incidence and complex anatomical structure make imaging examination and surgery face great challenges. To the best of our knowledge, such presentation of a low-grade myxofibrosarcoma that showed an extreme infiltrative growth pattern and presented severe pain has not been reported before. PATIENT CONCERNS: We reported a case of low-grade myxofibrosarcoma developed around the axillary neurovascular bundle, with multiple peripheral metastases in an 87-year-old male. Physical examination revealed a mass on the right axillary fossa measuring 5 × 4 cm. The patient underwent computed tomography but no definite diagnosis was obtained. Because he had claustrophobia and could not perform MRI examination. Thus, he underwent conventional ultrasound and contrast-enhanced ultrasound. Ultrasonic examination not only accurately determines the invasion scope of the tumor, but also clearly shows that the nerve has suffered from the invasion of the exogenous tumor and multiple metastatic foci around it. The contrast enhancement mode of the tumor showed centripetal high-enhancement, uneven internal enhancement, visible enhanced bridge, and non-enhancing central area. DIAGNOSES: Combined with the results of conventional ultrasound and contrast-enhanced ultrasound, we highly suspected it to be soft tissue sarcoma, giving strong clinical assistance. INTERVENTIONS: Given the risk of sarcoma implantation along the needle track and the underestimation of tumor malignancy, an excisional biopsy was considered the most practical choice to avoid unnecessary pain and potential implantation. OUTCOMES: The patient underwent surgery and a histopathological examination of the lesion confirmed it as low-grade myxofibrosarcoma. LESSONS SUBSECTIONS: This report describes a rare case of myxofibrosarcoma of the axillary fossa. High-resolution ultrasound is increasingly used for the initial assessment of soft-tissue masses. However, there are few reports about the ultrasound and contrast-enhanced ultrasound examinations of myxofibrosarcoma. Accurate preoperative diagnosis and proper treatment strategies are critical in managing patients with myxofibrosarcoma. Our case may provide diagnosis experiences and will help better understand and treat this disease.


Assuntos
Plexo Braquial , Fibrossarcoma , Histiocitoma Fibroso Maligno , Sarcoma , Neoplasias de Tecidos Moles , Idoso de 80 Anos ou mais , Humanos , Masculino , Plexo Braquial/diagnóstico por imagem , Fibrossarcoma/patologia , Dor , Neoplasias de Tecidos Moles/cirurgia , Tomografia Computadorizada por Raios X
20.
Artigo em Inglês | MEDLINE | ID: mdl-38152698

RESUMO

Due to the absence of in-enclave isolation, today's trusted execution environment (TEE), specifically Intel's Software Guard Extensions (SGX), does not have the capability to securely run different users' tasks within a single enclave, which is required for supporting real-world services, such as an in-enclave machine learning model that classifies the data from various sources, or a microservice (e.g., data search) that performs a very small task (within sub-seconds) for a user and therefore cannot afford the resources and the delay for creating a separate enclave for each user. To address this challenge, we developed Liveries, a technique that enables lightweight, verifiable in-enclave user isolation for protecting time-sharing services. Our approach restricts an in-enclave thread's privilege when configuring an enclave, and further performs integrity check and sanitization on critical enclave data upon user switches. For this purpose, we developed a novel technique that ensures the protection of sensitive user data (e.g., session keys) even in the presence of the adversary who may have compromised the enclave. Our study shows that the new technique is lightweight (1% overhead) and verifiable (about 3200 lines of code), making a step towards assured protection of real-world in-enclave services.

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