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Attaining elevated thermal conductivity in organic materials stands as a coveted objective, particularly within electronic packaging, thermal interface materials, and organic matrix heat exchangers. These applications have reignited interest in researching thermally conductive organic materials. The understanding of thermal transport mechanisms in these organic materials is currently constrained. This study concentrates on N, N'-dioctyl-3,4,9,10-perylenedicarboximide (PTCDI-C8), an organic conjugated crystal. A correlation between elevated thermal conductivity and augmented Young's modulus is substantiated through meticulous experimentation. Achievement via employing the physical vapor transport method, capitalizing on the robust CâC covalent linkages running through the organic matrix chain, bolstered by π-π stacking and noncovalent affiliations that intertwine the chains. The coexistence of these dynamic interactions, alongside the perpendicular alignment of PTCDI-C8 molecules, is confirmed through structural analysis. PTCDI-C8 thin film exhibits an out-of-plane thermal conductivity of 3.1 ± 0.1 W m-1 K-1, as determined by time-domain thermoreflectance. This outpaces conventional organic materials by an order of magnitude. Nanoindentation tests and molecular dynamics simulations elucidate how molecular orientation and intermolecular forces within PTCDI-C8 molecules drive the film's high Young's modulus, contributing to its elevated thermal conductivity. This study's progress offers theoretical guidance for designing high thermal conductivity organic materials, expanding their applications and performance potential.
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Choroidal neovascularization (CNV) is the primary pathogenic process underlying wet age-related macular degeneration, leading to severe vision loss. Despite current anti-vascular endothelial growth factor (VEGF) therapies, several limitations persist. Crocetin, a major bioactive constituent of saffron, exhibits multiple pharmacological activities, yet its role and mechanism in CNV remain unclear. Here, we investigated the potential effects of crocetin on CNV using in vitro and in vivo models. In human umbilical vein endothelial cells, crocetin demonstrated inhibition of VEGF-induced cell proliferation, migration, and tube formation in vitro, as assessed by CCK-8 and EdU assays, transwell and scratch assays, and tube formation analysis. Additionally, crocetin suppressed choroidal sprouting in ex vivo experiments. In the human retinal pigment epithelium (RPE) cell line ARPE-19, crocetin attenuated cobalt chloride-induced hypoxic cell injury, as evidenced by CCK-8 assay. As evaluated by quantitative PCR and Western blot assay, it also reduced hypoxia-induced expression of VEGF and hypoxia-inducible factor 1α (HIF-1α), while enhancing zonula occludens-1 expression. In a laser-induced CNV mouse model, intravitreal administration of crocetin significantly reduced CNV size and suppressed elevated expressions of VEGF, HIF-1α, TNFα, IL-1ß, and IL-6. Moreover, crocetin treatment attenuated the elevation of phospho-S6 in laser-induced CNV and hypoxia-induced RPE cells, suggesting its potential anti-angiogenic effects through antagonizing the mechanistic target of rapamycin complex 1 (mTORC1) signaling. Our findings indicate that crocetin may hold promise as an effective drug for the prevention and treatment of CNV.
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Neovascularização de Coroide , Células Endoteliais , Camundongos , Animais , Humanos , Células Endoteliais/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Sincalida/metabolismo , Neovascularização de Coroide/tratamento farmacológico , Neovascularização de Coroide/prevenção & controle , Neovascularização de Coroide/metabolismo , Hipóxia/metabolismo , Modelos Animais de Doenças , Epitélio Pigmentado da Retina/metabolismoRESUMO
Wet age-related macular degeneration (wAMD) is the main cause of irreversible blindness in the elderly, and its pathogenesis is still not fully understood. Long non-coding RNAs (lncRNAs) participated in the pathogenesis of a number of neovascular diseases, but their role in wAMD is less known. In order to reveal the potential role of lncRNAs in wAMD, we used high-throughput sequencing to assess lncRNAs and mRNAs expression profile in the aqueous humor of patients with wAMD and of patients with age-related cataract as control. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed to identify the potential biological functions and signaling pathways of RNA. A coding-non-coding gene co-expression (CNC) network was constructed to identify the interaction of lncRNAs and mRNAs. Quantitative PCR was used to validate the expression of selected lncRNAs. We identified 1071 differentially expressed lncRNAs and 3658 differentially expressed mRNAs in patients with wAMD compared to controls. GO and KEGG analyses suggested that differentially expressed lncRNAs-coexpressed mRNAs were mainly enriched in Rab GTPase binding, GTPase activation, RAS signaling pathway and autophagy. The top 100 differentially expressed genes were selected to build the CNC network, which could be connected by 416 edges. LncRNAs are differentially expressed in the aqueous humor of patients with wAMD and they are involved in several pathogenetic pathways. These dysregulated lncRNAs and their target genes could represent promising therapeutic targets in wAMD.
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Degeneração Macular , RNA Longo não Codificante , Humanos , Idoso , Perfilação da Expressão Gênica , RNA Longo não Codificante/genética , Humor Aquoso/metabolismo , Transdução de Sinais , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Redes Reguladoras de GenesRESUMO
Site-specific modification is a great challenge for polysaccharide scientists. Chemo- and regioselective modification of polysaccharide chains can provide many useful natural-based materials and help us illuminate fundamental structure-property relationships of polysaccharide derivatives. The hemiacetal reducing end of a polysaccharide is in equilibrium with its ring-opened aldehyde form, making it the most uniquely reactive site on the polysaccharide molecule, ideal for regioselective decoration such as imine formation. However, all natural polysaccharides, whether they are branched or not, have only one reducing end per chain, which means that only one aldehyde-reactive substituent can be added. We introduce a new approach to selective functionalization of polysaccharides as an entrée to useful materials, appending multiple reducing ends to each polysaccharide molecule. Herein, we reduce the approach to practice using amide formation. Amine groups on monosaccharides such as glucosamine or galactosamine can react with carboxyl groups of polysaccharides, whether natural uronic acids like alginates, or derivatives with carboxyl-containing substituents such as carboxymethyl cellulose (CMC) or carboxymethyl dextran (CMD). Amide formation is assisted using the coupling agent 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMTMM). By linking the C2 amines of monosaccharides to polysaccharides in this way, a new class of polysaccharide derivatives possessing many reducing ends can be obtained. We refer to this class of derivatives as multi-reducing-end polysaccharides (MREPs). This new family of derivatives creates the potential for designing polysaccharide-based materials with many potential applications, including in hydrogels, block copolymers, prodrugs, and as reactive intermediates for other derivatives.
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Alginatos , Polissacarídeos , Polissacarídeos/química , Alginatos/química , Monossacarídeos , Aldeídos , AmidasRESUMO
Systemic sclerosis (SSc) is characterised by progressive multiple organ fibrosis leading to morbidity and mortality. Lysyl oxidases play a vital role in the cross-linking of collagens and subsequent build-up of fibrosis in the extracellular matrix. As such, their inhibition provides a novel treatment paradigm for SSc. A novel small molecule pan-lysyl oxidase inhibitor, PXS-5505, currently in clinical development for myelofibrosis treatment was evaluated using in vivo rodent models resembling the fibrotic conditions in SSc. Both lysyl oxidase and lysyl oxidase-like 2 (LOXL2) expression were elevated in the skin and lung of SSc patients. The oral application of PXS-5505 inhibited lysyl oxidase activity in the skin and LOXL2 activity in the lung. PXS-5505 exhibited anti-fibrotic effects in the SSc skin mouse model, reducing dermal thickness and α-smooth muscle actin. Similarly, in the bleomycin-induced mouse lung model, PXS-5505 reduced pulmonary fibrosis toward normal levels, mediated by its ability to normalise collagen/elastin crosslink formation. PXS-5505 also reduced fibrotic extent in models of the ischaemia-reperfusion heart, the unilateral ureteral obstruction kidney, and the CCl4-induced fibrotic liver. PXS-5505 consistently demonstrates potent anti-fibrotic efficacy in multiple models of organ fibrosis relevant to the pathogenesis of SSc, suggesting that it may be efficacious as a novel approach for treating SSc.
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Colágeno , Inibidores Enzimáticos , Proteína-Lisina 6-Oxidase , Escleroderma Sistêmico , Animais , Colágeno/antagonistas & inibidores , Colágeno/metabolismo , Modelos Animais de Doenças , Fibrose , Humanos , Camundongos , Proteína-Lisina 6-Oxidase/antagonistas & inibidores , Proteína-Lisina 6-Oxidase/metabolismo , Roedores/metabolismo , Escleroderma Sistêmico/tratamento farmacológico , Escleroderma Sistêmico/enzimologiaRESUMO
This study investigates the epidemiological characteristics of high-risk human papillomavirus (hrHPV) and analyzes the risk of cervical lesions among women in Zhejiang province, China. HPV data were collected retrospectively from a cohort of 67 742 women who underwent routine cervical cancer screening from 2010 to 2019. Precancerous and cervical cancer cases (n = 980) were histologically diagnosed as a low-grade squamous intraepithelial lesion (LSIL; n = 341) or a high-grade squamous intraepithelial lesion (HSIL; n = 499) and invasive cervical cancer (ICC) (n = 140) groups. Disordered logistic regression analysis was used to test the relationship between different degrees of cervical lesions, HPV16/18 infection status, positive rate of p16INK4a (p16), Ki-67 expression, and patient's age in SIL and ICC (270/980 cases) patients. HPV52 (4.7%) was the most prevalent HPV type, followed by HPV16 (3.3%) and HPV58 (2.6%). HPV16 was the most common HPV in SIL, peaking at the age of 30-39. The HPV16 infection rate was significantly higher in HSIL than in LSIL patients; moreover, HPV16, HPV18, and HPV51 infection rates were significantly higher in ICC patients than in HSIL (Bonferroni-adjusted p < 0.0167). The presence of HPV16/18 was also associated with a higher risk of developing HSIL from LSIL (odds ratio [OR] = 9.198, 95% confidence interval [CI]: 2.76-127.49). The increased p16 expression and HPV16/18 were associated with the increased risk of cancer progression (OR = 1.092, 95% CI: 1.03-1.36; OR = 1.495, 95% CI: 1.23-2.19, respectively). The identified hrHPV genotypes in cervical lesions can serve as a baseline indicator for future vaccine assessment in Zhejiang, China.
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Colo do Útero/patologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/virologia , Adulto , Idoso , Colo do Útero/virologia , China/epidemiologia , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Feminino , Genótipo , Humanos , Pessoa de Meia-Idade , Papillomaviridae/classificação , Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/patologia , Lesões Pré-Cancerosas/epidemiologia , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/virologia , Prevalência , Estudos Retrospectivos , Fatores de Risco , Lesões Intraepiteliais Escamosas Cervicais/epidemiologia , Lesões Intraepiteliais Escamosas Cervicais/patologia , Lesões Intraepiteliais Escamosas Cervicais/virologia , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Adulto JovemRESUMO
Owing to the growing heat removal issue in modern electronic devices, electrically insulating polymer composites with high thermal conductivity have drawn much attention during the past decade. However, the conventional method to improve through-plane thermal conductivity of these polymer composites usually yields an undesired value (below 3.0 Wm-1 K-1 ). Here, construction of a 3D phonon skeleton is reported composed of stacked boron nitride (BN) platelets reinforced with reduced graphene oxide (rGO) for epoxy composites by the combination of ice-templated and infiltrating methods. At a low filler loading of 13.16 vol%, the resulting 3D BN-rGO/epoxy composites exhibit an ultrahigh through-plane thermal conductivity of 5.05 Wm-1 K-1 as the best thermal-conduction performance reported so far for BN sheet-based composites. Theoretical models qualitatively demonstrate that this enhancement results from the formation of phonon-matching 3D BN-rGO networks, leading to high rates of phonon transport. The strong potential application for thermal management has been demonstrated by the surface temperature variations of the composites with time during heating and cooling.
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Owing to the growing heat removal issue of modern electronic devices, polymer composites with high thermal conductivity have drawn much attention in the past few years. However, a traditional method to enhance the thermal conductivity of the polymers by addition of inorganic fillers usually creates composite with not only limited thermal conductivity but also other detrimental effects due to large amount of fillers required. Here, novel polymer composites are reported by first constructing 3D boron nitride nanosheets (3D-BNNS) network using ice-templated approach and then infiltrating them with epoxy matrix. The obtained polymer composites exhibit a high thermal conductivity (2.85 W m(-1) K(-1)), a low thermal expansion coefficient (24-32 ppm K(-1)), and an increased glass transition temperature (T(g)) at relatively low BNNSs loading (9.29 vol%). These results demonstrate that this approach opens a new avenue for design and preparation of polymer composites with high thermal conductivity. The polymer composites are potentially useful in advanced electronic packaging techniques, namely, thermal interface materials, underfill materials, molding compounds, and organic substrates.
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NEW FINDINGS: What is the central question of this study? Can bilateral renal denervation, an effective antihypertensive treatment in clinical and experimental studies, improve cardiac ß-adrenoceptor responsiveness in a diabetic model with underlying hypertension? What is the main finding and its importance? Bilateral renal denervation did not affect ß-adrenergic responsiveness in the diabetic hypertensive rat heart, but denervation reduced the hypertension-induced concentric hypertrophic remodelling. This suggests that the positive haemodynamic changes induced by renal denervation are most likely to reflect an attenuation of sympathetic effects on the systemic vasculature and/or the renal function rather than direct sympathetic modulation of the heart. Bilateral renal denervation (BRD) has been shown to normalise blood pressure in clinical and experimental studies of hypertension by reducing systemic sympathetic output. This study determined the effect of BRD on cardiac ß-adrenoceptor (AR) responsiveness in a diabetic model with underlying hypertension using the transgenic (mRen-2)27 rats. Bilateral renal denervation or sham surgeries were conducted repeatedly at 3, 6 and 9 weeks in Ren-2 rats with or without streptozotocin (STZ)-induced diabetes (4 × n = 7); Sprague-Dawley rats (n = 6) served as control animals. Cardiac function was determined in isolated hearts at 18 weeks of age. Normalised left ventricular developed pressure and relaxation was recorded in response to incremental concentrations of the ß-AR agonist isoprenaline (from 10-10 to 10-7 m) or the ß3 -AR agonist BRL37344 (from 10(-13) to 10(-6 ) m). Expression levels of ß1 -AR were determined by Western blot. Both inotropic and lusitropic ß-AR responsiveness was reduced in the hypertensive diabetic hearts, but these responses were unaltered after BRD. Expression levels of ß1 -AR were increased after BRD (Sham, 0.85 ± 0.11 versus 1.01 ± 0.05 a.u.; BRD, 1.45 ± 0.11 versus 1.46 ± 0.07 a.u.; Ren-2 versus Ren-2 STZ, P < 0.05 versus Sham). No effect of ß3 -AR agonist stimulation with BRL37344 was observed. Interestingly, BRD increased left ventricular diastolic volume in both the Ren-2 and the Ren-2 STZ groups. Bilateral renal denervation did not restore the attenuated cardiac ß-AR responsiveness in the diabetic hypertensive rats, but it reduced the extent of hypertension-induced concentric hypertrophic remodelling. Thus, the haemodynamic protection offered by renal denervation appears to reflect an attenuated sympathetic innervation of the systemic vasculature and/or kidney rather than a direct cardiac effect.
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Cardiomegalia/cirurgia , Diabetes Mellitus Tipo 1/cirurgia , Hipertensão/cirurgia , Rim/inervação , Miocárdio/metabolismo , Receptores Adrenérgicos beta 1/metabolismo , Simpatectomia , Sistema Nervoso Simpático/cirurgia , Remodelação Ventricular , Agonistas de Receptores Adrenérgicos beta 1/farmacologia , Animais , Pressão Sanguínea , Cardiomegalia/metabolismo , Cardiomegalia/fisiopatologia , Cardiotônicos/farmacologia , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 1/fisiopatologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Preparação de Coração Isolado , Contração Miocárdica , Ratos Sprague-Dawley , Ratos Transgênicos , Receptores Adrenérgicos beta 1/efeitos dos fármacos , Transdução de Sinais , Sistema Nervoso Simpático/metabolismo , Sistema Nervoso Simpático/fisiopatologia , Fatores de Tempo , Função Ventricular Esquerda , Pressão Ventricular , Remodelação Ventricular/efeitos dos fármacosRESUMO
We created 66 male and 74 female virtual three-dimensional models of the pelvis based on computed tomography data from 140 patients. Virtual cylindrical bolts (VCBs) were placed in the anterior column (AC), which was then resliced serially along the bolt's long axis. AC screw tunnel mainly comprises two long, narrow triangular prisms [zone III (acetabular fossa) and zone V (obturator foramen)]--forming the III/V angle--linked by a larger, shorter cylinder [zone IV (acetabular notch)]. VCBs' mean length and maximum diameter were 111.13 ± 7.33 and 7.37 ± 1.90 mm, respectively. The models' anatomical zone lengths were similar between the sexes. Zone V's narrowest diameters and the III/V angles were significantly different. VCBs >6.5 mm were accommodated in 65 of 66 male models and 31 of 74 female models. VCBs >5.0 and <6.5 mm were accommodated in one male and 30 female models. Eleven female models accommodated only VCBs >3.5 and <5.0 mm. However, to 13 female pelvic models with maximum VCB accommodation of <5 mm for the anterior column, the maximum diameter of the VCBs was 8.23 ± 1.22 mm in medial passage and 10.3 ± 1.91 mm in lateral passage, respectively. Percutaneous fixation of the AC with screws is a safe technique, even though in Chinese female patients. The narrowest diameters in zone V and the III/V angles are the key factors for application of AC screws. Female patients with a smaller interosseous space at zone V and a large III/V angle can accommodate segmental passage screws.
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Acetábulo/lesões , Simulação por Computador , Fixação Interna de Fraturas/instrumentação , Fraturas Ósseas/cirurgia , Modelos Anatômicos , Ossos Pélvicos/anatomia & histologia , Adulto , Povo Asiático , Parafusos Ósseos , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ossos Pélvicos/diagnóstico por imagem , Tomografia Computadorizada por Raios XRESUMO
Bilateral renal denervation (BRD) has been shown to reduce hypertension and improve renal function in both human and experimental studies. We hypothesized that chronic intervention with BRD may also attenuate renal injury and fibrosis in diabetic nephropathy. This hypothesis was examined in a female streptozotocin-induced diabetic (mRen-2)27 rat (TGR) shown to capture the cardinal features of human diabetic nephropathy. Following diabetic induction, BRD/sham surgeries were conducted repeatedly (at the week 3, 6, and 9 following induction) in both diabetic and normoglycemic animals. Renal denervation resulted in a progressive decrease in systolic blood pressure from first denervation to termination (at 12 wk post-diabetic induction) in both normoglycemic and diabetic rats. Renal norepinephrine content was significantly raised following diabetic induction and ablated in denervated normoglycemic and diabetic groups. A significant increase in glomerular basement membrane thickening and mesangial expansion was seen in the diabetic kidneys; this morphological appearance was markedly reduced by BRD. Immunohistochemistry and protein densitometric analysis of diabetic innervated kidneys confirmed the presence of significantly increased levels of collagens I and IV, α-smooth muscle actin, the ANG II type 1 receptor, and transforming growth factor-ß. Renal denervation significantly reduced protein expression of these fibrotic markers. Furthermore, BRD attenuated albuminuria and prevented the loss of glomerular podocin expression in these diabetic animals. In conclusion, BRD decreases systolic blood pressure and reduces the development of renal fibrosis, glomerulosclerosis, and albuminuria in this model of diabetic nephropathy. The evidence presented strongly suggests that renal denervation may serve as a therapeutic intervention to attenuate the progression of renal injury in diabetic nephropathy.
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Injúria Renal Aguda/prevenção & controle , Denervação/métodos , Diabetes Mellitus Experimental/complicações , Nefropatias Diabéticas/complicações , Rim/inervação , Renina/genética , Injúria Renal Aguda/patologia , Injúria Renal Aguda/fisiopatologia , Animais , Membrana Basal/patologia , Diabetes Mellitus Experimental/induzido quimicamente , Nefropatias Diabéticas/patologia , Nefropatias Diabéticas/fisiopatologia , Modelos Animais de Doenças , Progressão da Doença , Feminino , Fibrose , Heterozigoto , Glomérulos Renais/patologia , Ratos , Ratos Transgênicos , Renina/fisiologia , Estreptozocina/efeitos adversosRESUMO
RATIONALE AND OBJECTIVES: Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of non-small cell lung cancer (NSCLC) and programmed cell death-ligand 1 (PD-L1) is a companion biomarker. This study aims to use baseline arterial-phase enhanced CT (APECT) to construct efficient radiomic models for predicting PD-L1 expression and immunotherapy prognosis in NSCLC. MATERIALS AND METHODS: We extracted radiomics features from the baseline APECT images of 204 patients enrolled in a published multicenter clinical trial that commenced on August 23, 2018, and concluded on November 15, 2019 (ClinicalTrials.gov: NCT03607539). Of these patients, 146 patients from selected centers were assigned to the training cohort. The least absolute shrinkage and selection operator (LASSO) method was used to reduce dimensionality of radiomics features and calculate tumor scores. Models were created using naive bayes, decision trees, XGBoost, and random forest algorithms according to tumor scores. These models were then validated in an independent validation cohort comprising 58 patients from the remaining centers. RESULTS: The random forest algorithm outperformed the other methods. In the three-classification scenario, the random forest model achieving the area under the curve (AUC) values of 0.98 and 0.94 in the training and validation cohorts, respectively. In the two-classification scenario, the random forest model achieved AUCs of 0.99 (95%CI: 0.97-1.0, P < 0.0001) and 0.93 (95%CI: 0.83-0.98, P < 0.0001) in the training and validation cohorts, respectively. Furthermore, patients classified as PD-L1 high-expression by this model can predict treatment response (AUC=0.859, 95%CI: 0.7-0.96, P < 0.001) and improved survival (HR=0.2, 95%CI: 0.08-0.53, P = 0.001) only in validation sintilimab arm. CONCLUSION: Radiomics models based on APECT represent a potential non-invasive approach to robustly predict PD-L1 expression and ICI treatment outcomes in patients with NSCLC, which could significantly improve precision cancer immunotherapy.
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Polysaccharide-based hydrogels are promising for many biomedical applications including drug delivery, wound healing, and tissue engineering. We illustrate herein self-healing, injectable, fast-gelling hydrogels prepared from multi-reducing end polysaccharides, recently introduced by the Edgar group. Simple condensation of reducing ends from multi-reducing end alginate (M-Alg) with amines from polyethylene imine (PEI) in water affords a dynamic, hydrophilic polysaccharide network. Trace amounts of acetic acid can accelerate the gelation time from hours to seconds. The fast-gelation behavior is driven by rapid Schiff base formation and strong ionic interactions induced by acetic acid. A cantilever rheometer enables real-time monitoring of changes in viscoelastic properties during hydrogel formation. The reversible nature of these crosslinks (imine bonds, ionic interactions) provides a hydrogel with low toxicity in cell studies as well as self-healing and injectable properties. Therefore, the self-healing, injectable, and fast-gelling M-Alg/PEI hydrogel holds substantial promise for biomedical, agricultural, controlled release, and other applications.
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Alginatos , Hidrogéis , Polissacarídeos , Alginatos/química , Hidrogéis/química , Hidrogéis/síntese química , Hidrogéis/farmacologia , Polissacarídeos/química , Polietilenoimina/química , Humanos , Reologia , Animais , Bases de Schiff/química , Injeções , CamundongosRESUMO
Zwitterionic polymers, with their equal amounts of cationic and anionic functional groups, have found widespread utility including as non-fouling coatings, hydrogel materials, stabilizers, antifreeze materials, and drug carriers. Polysaccharide-derived zwitterionic polymers are attractive because of their sustainable origin, potential for lower toxicity, and possible biodegradability, but previous methods for synthesis of zwitterionic polysaccharide derivatives have been limited in terms of flexibility and attainable degree of substitution (DS) of charged entities. We report herein successful design and synthesis of zwitterionic polysaccharide derivatives, in this case based on cellulose, by reductive amination of oxidized 2-hydroxypropyl cellulose (Ox-HPC) with ω-aminoalkanoic acids. Reductive amination products could be readily obtained with DS(cation) (= DS(anion)) up to 1.6. Adduct hydrophilic/hydrophobic balance (amphiphilicity) can be influenced by selecting the appropriate chain length of the ω-aminoalkanoic acid. This strategy is shown to produce a range of amphiphilic, water-soluble, moderately high glass transition temperature (Tg) polysaccharide derivatives in just a couple of efficient steps from commercially available building blocks. The adducts were evaluated as crystallization inhibitors. They are strong inhibitors of crystallization even for the challenging, poorly soluble, fast-crystallizing prostate cancer drug enzalutamide, as supported by surface tension and Flory-Huggins interaction parameter results.
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Background: Kidney renal clear cell carcinoma (KIRC) is not sensitive to radiotherapy and chemotherapy, and only some KIRC patients can benefit from immunotherapy and targeted therapy. Cuproptosis is a new mechanism of cell death, which is closely related to tumor progression, prognosis and immunity. The identification of prognostic markers related to cuproptosis in KIRC may provide targets for treatment and improve the prognosis of KIRC patients. Methods: Ten cuproptosis-related genes were analyzed for differential expression in KIRC-TCGA and a prognostic model was constructed. Nomogram diagnostic model was used to screen independent prognostic molecules. The screened molecules were verified in multiple datasets (GSE36895 and GSE53757), and in KIRC tumor tissues by RT-PCR and immunohistochemistry (IHC). Clinical correlation of cuproptosis-related independent prognostic molecules was analyzed. According to the molecular expression, the two groups were divided into high and low expression groups, and the differences of immune checkpoint and tumor infiltrating lymphocytes (TILs) between the two groups were compared by EPIC algorithm. The potential Immune checkpoint blocking (ICB) response of high and low expression groups was predicted by the "TIDE" algorithm. Results: FDX1 and DLAT were protective factors, while CDKN2A was a risk factor. FDX1 was an independent prognostic molecule by Nomogram, and low expressed in tumor tissues compared with adjacent tissues (p < 0.05). FDX1 was positively correlated with CD274, HAVCR2, PDCD1LG2, and negatively correlated with CTLA4, LAG3, and PDCD1. The TIDE score of low-FDX1 group was higher than that of high-FDX1 group. The abundance of CD4+ T cells, CD8+ T cells and Endothelial cells in FDX1-low group was lower than that in FDX1-high group (p < 0.05). Conclusion: FDX1, as a key cuproptosis-related gene, was also an independent prognostic molecule of KIRC. FDX1 might become an interesting biomarker and potential therapeutic target for KIRC.
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Objective: Due to the increased likelihood of progression of severe pneumonia, the mortality rate of the elderly infected with coronavirus disease 2019 (COVID-19) is high. However, there is a lack of models based on immunoglobulin G (IgG) subtypes to forecast the severity of COVID-19 in elderly individuals. The objective of this study was to create and verify a new algorithm for distinguishing elderly individuals with severe COVID-19. Methods: In this study, laboratory data were gathered from 103 individuals who had confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection using a retrospective analysis. These individuals were split into training (80%) and testing cohort (20%) by using random allocation. Furthermore, 22 COVID-19 elderly patients from the other two centers were divided into an external validation cohort. Differential indicators were analyzed through univariate analysis, and variable selection was performed using least absolute shrinkage and selection operator (LASSO) regression. The severity of elderly patients with COVID-19 was predicted using a combination of five machine learning algorithms. Area under the curve (AUC) was utilized to evaluate the performance of these models. Calibration curves, decision curves analysis (DCA), and Shapley additive explanations (SHAP) plots were utilized to interpret and evaluate the model. Results: The logistic regression model was chosen as the best machine learning model with four principal variables that could predict the probability of COVID-19 severity. In the training cohort, the model achieved an AUC of 0.889, while in the testing cohort, it obtained an AUC of 0.824. The calibration curve demonstrated excellent consistency between actual and predicted probabilities. According to the DCA curve, it was evident that the model provided significant clinical advantages. Moreover, the model performed effectively in an external validation group (AUC=0.74). Conclusion: The present study developed a model that can distinguish between severe and non-severe patients of COVID-19 in the elderly, which might assist clinical doctors in evaluating the severity of COVID-19 and reducing the bad outcomes of elderly patients.
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COVID-19 , Imunoglobulina G , Idoso , Humanos , Estudos Retrospectivos , SARS-CoV-2 , Gravidade do Paciente , Aprendizado de MáquinaRESUMO
Purpose: Myocardial injury, as a serious complication of coronavirus disease-2019 (COVID-19), increases the occurrence of adverse outcomes. Identification of key regulatory molecules of myocardial injury may help formulate corresponding treatment strategies and improve the prognosis of COVID-19 patients. Methods: Gene Set Enrichment Analysis (GSEA) was conducted to identify co-regulatory pathways. Differentially expressed genes (DEGs) in GSE150392 and GSE169241 were screened and an intersection analysis with key genes of the co-regulatory pathway was conducted. A protein-protein interaction (PPI) network was constructed to screen for key regulatory genes. Preliminarily screened genes were verified using other datasets to identify genes with consistent expression. Based on the hierarchical cluster, we divided the patients from GSE177477 into high- and low-risk groups and compared the proportion of immune cells. A total of 267 COVID-19 patients from the Zhejiang Provincial Hospital of Chinese Medicine from December 26, 2022, to January 11, 2023, were enrolled to verify the bioinformatics results. Univariate and multivariate analyses were performed to analyze the risk factors for myocardial injury. According to high-sensitivity troponin (hsTnI) levels, patients with COVID-19 were divided into high- and low-sensitivity groups, and interleukin 6 (IL6) expression and lymphocyte subsets were compared. Patients were also divided into high and low groups according to the IL6 expression, and hsTnI levels were compared. Results: Interleukin signaling pathway and GPCR ligand binding were shown to be co-regulatory pathways in myocardial injury associated with COVID-19. According to the hierarchical cluster analysis of seven genes (IL6, NFKBIA, CSF1, CXCL1, IL1R1, SOCS3, and CASP1), patients with myocardial injury could be distinguished from those without myocardial injury. Age, IL6 levels, and hospital stay may be factors influencing myocardial injury caused by COVID-19. Compared with COVID-19 patients without myocardial injury, the levels of IL6 in patients with myocardial injury increased, while the number of CD4+ T cells, CD8+ T cells, B cells, and NK cells decreased (P<0.05). The hsTnI levels in COVID-19 patients with high IL6 levels were higher than those in patients with low IL6 (P<0.05). Conclusions: The COVID-19 patients with myocardial injury had elevated IL6 expression and decreased lymphocyte counts. IL6 may participate in myocardial injury through the interleukin signaling pathway.
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Polysaccharide-based Schiff base hydrogels have promise for drug delivery, tissue engineering, and many other applications due to their reversible imine bond crosslinks. We describe herein pH-responsive, injectable, and self-healing hydrogels prepared by reacting oxidized hydroxypropyl cellulose (Ox-HPC) with carboxymethyl chitosan (CMCS). Simple combination of ketones from Ox-HPC side chains with amines from CMCS in water provides a dynamic, hydrophilic polysaccharide network. The reversible nature of these imine bonds in the presence of water provides a hydrogel with injectable and self-healing properties. Phenylalanine as a model amine-containing drug was linked by imine bonds to Ox-HPC within the hydrogel. Phenylalanine release was faster at the pH of the extracellular space around tumors (6.8) than in normal tissues (7.4), a surprising degree of pH sensitivity. Therefore, Ox-HPC/CMCS hydrogels show promise as drug carriers that may selectively target even slightly lower pH environments like the extracellular milieu around cancer cells.
Assuntos
Celulose Oxidada , Quitosana , Hidrogéis/química , Quitosana/química , Liberação Controlada de Fármacos , Derivados da Hipromelose , Polissacarídeos/química , Concentração de Íons de Hidrogênio , Água , Iminas , FenilalaninaRESUMO
Porous skeletons play a crucial role in various applications. Their fundamental significance stems from their remarkable surface area and capacity to enhance mass adsorption and transport. Freeze-casting is a commonly utilized methodology for the production of porous skeletons featuring vertically aligned channels. Nevertheless, the resultant single-oriented skeleton displays anisotropic mass transfer characteristics and suboptimal mechanical properties. Our investigation was motivated by the intricate microstructures observed in botanical organisms, leading us to devise an advanced freeze-casting methodology. A novel central-radial skeleton with significantly enhanced capabilities has been successfully engineered. The central-radial architecture demonstrates superior refinement and uniformity in its pore structure, featuring an axial mass transfer axis and meticulously arranged radial channels. This microstructure endows the porous skeleton with a higher compression resilience, superior adsorption rate, and structural maintenance capacity. Through a rigorous examination of the thermal conductivity of skeleton-filled composites coupled with comprehensive COMSOL simulations, the exceptional characteristics of this unique structural arrangement have been definitively ascertained. Furthermore, the efficacy of implementing this skeleton in chip cooling and photothermal conversion has been convincingly substantiated. Our pioneering method of microstructure preparation, employing freeze-casting, holds immense potential in expanding its applicability and inspiring innovative concepts for the advancement of novel structures.
RESUMO
As the features of electronics are miniaturized, the need for interfacial thermal coupling layers to enhance their thermal transfer efficiency and improve device performance becomes critical. Organic conjugated small molecules possess a unique combination of periodic crystal structures and conjugated units with π electrons, resulting in notable thermal conductivities and molecular structure orientation that facilitates directed heat transfer. Nevertheless, there is a noticeable gap in literatures regarding the thermal properties of organic conjugated small molecules and their potential applications in nanoscale thermal management. Herein, we report the fabrication of high-quality thin films of organic conjugated small molecules. The result reveals that the 2D organic conjugated small molecule thin films exhibit a high cross-plane thermal conductivity of 3.2 W/m K. The increased thermal conductivity is attributed to the well-organized lattice structure and existence of π-electrons induced by conjugated systems. The studied conjugated small molecules engage in π-π stacking interactions with carbon materials and efficiently exchange energy with electrons in metals, promoting rapid interfacial heat transfer. These molecules act as coupling layers, significantly enhancing thermal transfer efficiency between graphite-based thermal pads and copper heat sinks. This pioneering research represents the inaugural investigation of the thermal performance of conjugated organic small molecules. These findings highlight the potential of conjugated small molecules as thermal coupling layers, offering tunable combinations of desirable properties.