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1.
Macromol Rapid Commun ; 45(5): e2300543, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38102953

RESUMEN

Entropy is a universal concept across the physics of mixtures. While the role of entropy in other multicomponent materials has been appreciated, its effects in polymers and plastics have not. In this work, it is demonstrated that the seemingly small mixing entropy contributes to the miscibility and performance of polymer alloys. Experimental and modeling studies on over 30 polymer pairs reveal a strong correlation between entropy, morphology, and mechanical properties, while elucidating the mechanism behind: in polymer blends with weak interactions, entropy leads to homogeneously dispersed nanosized domains stabilized by highly entangled chains. This unique microstructure promotes uniform plastic deformation at the interface, thus improving the toughness of conventional brittle polymers by 1-2 orders of magnitude without sacrificing other properties, analogous to high-entropy metallic alloys. The proposed strategy also applies to ternary polymer systems and copolymers, offering a new pathway toward the development of sustainable polymers.


Asunto(s)
Aleaciones , Polímeros , Entropía , Polímeros/química , Aleaciones/química , Plásticos
2.
Oral Dis ; 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38287672

RESUMEN

Intraflagellar transport (IFT) proteins have been reported to regulate cell growth and differentiation as the essential functional component of primary cilia. The effects of IFT80 on early bone healing of extraction sockets have not been well studied. To investigate whether deletion of Ift80 in alveolar bone-derived mesenchymal stem cells (aBMSCs) affected socket bone healing, we generated a mouse model of specific knockout of Ift80 in Prx1 mesenchymal lineage cells (Prx1Cre ;IFT80f/f ). Our results demonstrated that deletion of IFT80 in Prx1 lineage cells decreased the trabecular bone volume, ALP-positive osteoblastic activity, TRAP-positive osteoclastic activity, and OSX-/COL I-/OCN-positive areas in tooth extraction sockets of Prx1Cre ; IFT80f/f mice compared with IFT80f/f littermates. Furthermore, aBMSCs from Prx1Cre ; IFT80f/f mice showed significantly decreased osteogenic markers and downregulated migration and proliferation capacity. Importantly, the overexpression of TAZ recovered significantly the expressions of osteogenic markers and migration capacity of aBMSCs. Lastly, the local administration of lentivirus for TAZ enhanced the expression of RUNX2 and OSX and promoted early bone healing of extraction sockets from Prx1Cre ; IFT80f/f mice. Thus, IFT80 promotes osteogenesis and early bone healing of tooth sockets through the activation of TAZ/RUNX2 pathway.

3.
FASEB J ; 36(8): e22423, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35775626

RESUMEN

Orthodontic tooth movement (OTM) is induced by biomechanical stimuli and facilitated by periodontal tissue remodeling, where multiple immune cells participate in this progression. It has been demonstrated that macrophage is essential for mechanical force-induced tissue remodeling. In this study, we first found that mechanical force significantly induced macrophage proliferation in human periodontal samples and murine OTM models. Yet, how macrophages perceive mechanical stimuli and thereby modulate their biological behaviors remain elusive. To illustrate the mechanisms of mechanical force-induced macrophage proliferation, we subsequently identified Piezo1, a novel mechanosensory ion channel, to modulate macrophage response subjected to mechanical stimuli. Mechanical force upregulates Piezo1 expression in periodontal tissues and cultured bone-marrow-derived macrophages (BMDMs). Remarkably, suppressing Piezo1 with GsMTx4 retarded OTM through reduced macrophage proliferation. Moreover, knockdown of Piezo1 effectively inhibited mechanical force-induced BMDMs proliferation. RNA sequencing was further performed to dissect the underlying mechanisms of Piezo1-mediated mechanotransduction utilizing mechanical stretch system. We revealed that Piezo1-activated AKT/GSK3ß signaling was closely associated with macrophage proliferation upon mechanical stimuli. Importantly, Cyclin D1 (Ccnd1) was authenticated as a critical downstream factor of Piezo1 that facilitated proliferation by enhancing Rb phosphorylation. We generated genetically modified mice in which Ccnd1 could be deleted in macrophages in an inducible manner. Conditional ablation of Ccnd1 inhibited periodontal macrophage proliferation and therefore delayed OTM. Overall, our findings highlight that proliferation driven by mechanical force is a key process by which macrophages infiltrate in periodontal tissue during OTM, where Piezo1-AKT-Ccnd1 axis plays a pivotal role.


Asunto(s)
Ciclina D1 , Canales Iónicos , Macrófagos , Proteínas Proto-Oncogénicas c-akt , Animales , Proliferación Celular , Ciclina D1/genética , Ciclina D1/metabolismo , Humanos , Canales Iónicos/genética , Canales Iónicos/metabolismo , Macrófagos/citología , Macrófagos/metabolismo , Mecanotransducción Celular , Ratones , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal
4.
J Periodontal Res ; 58(5): 864-873, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37424315

RESUMEN

Periodontitis is a chronic, inflammatory, and destructive disease caused by the imbalance of host immune response and dental biofilm, and has strong epidemiological and pathogenesis correlations with systemic diseases. The immune response in periodontitis involves both innate and adaptive immunity, with numerous immune cells and inflammatory pathways participating in a complex network of interactions. In the past decade, the concept of "trained immunity" has emerged, which highlights the memory characteristics of innate immunity, thus opening up a new avenue of research. There is growing interest in exploring the role of trained immunity in chronic inflammatory and metabolic diseases such as atherosclerosis and diabetes mellitus. Evidence suggests that trained immunity may also regulate the onset and progression of periodontitis, serving as a bridge between periodontitis-related comorbidities. In this review, we summarize concepts related to trained immunity and its development. Furthermore, we present current evidence that endorses the notion of trained immunity in periodontitis and analyze possible roles it may assume regarding periodontitis-associated inflammatory reactions from a cellular perspective. Finally, we discuss various clinical therapeutic strategies for periodontitis and its associated comorbidities that target trained immunity. We hope that more researchers will pay attention to this emerging concept, thereby providing deeper insights into this novel field.


Asunto(s)
Periodontitis , Humanos , Inflamación , Inmunidad Innata , Inmunidad Entrenada
5.
J Nat Prod ; 86(4): 719-729, 2023 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-37023532

RESUMEN

Four new alkaloids, hippobrines A-D (1-4), along with three new polyacetylenes, hippobrenes A-C (5-7), were isolated from Hippobroma longiflora. Compounds 1-3 possess an unprecedented carbon skeleton. All of the new structures were determined by analyzing their mass and NMR spectroscopic data. The absolute configurations of 1 and 2 were confirmed by single-crystal X-ray analyses, and the absolute configurations of 3 and 7 were deduced using their ECD spectra. Plausible biogenetic pathways of 1 and 4 were proposed. In regard to bioactivities, all compounds (1-7) exhibited weak antiangiogenic activity against human endothelial progenitor cells, with IC50 values ranging from 21.1 ± 1.1 to 44.0 ± 2.3 µg/mL.


Asunto(s)
Alcaloides , Humanos , Estructura Molecular , Polímero Poliacetilénico , Alcaloides/farmacología , Alcaloides/química
6.
J Nanobiotechnology ; 21(1): 88, 2023 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-36915132

RESUMEN

BACKGROUND: Orthodontic tooth movement (OTM), a process of alveolar bone remodelling, is induced by mechanical force and regulated by local inflammation. Bone marrow-derived mesenchymal stem cells (BMSCs) play a fundamental role in osteogenesis during OTM. Macrophages are mechanosensitive cells that can regulate local inflammatory microenvironment and promote BMSCs osteogenesis by secreting diverse mediators. However, whether and how mechanical force regulates osteogenesis during OTM via macrophage-derived exosomes remains elusive. RESULTS: Mechanical stimulation (MS) promoted bone marrow-derived macrophage (BMDM)-mediated BMSCs osteogenesis. Importantly, when exosomes from mechanically stimulated BMDMs (MS-BMDM-EXOs) were blocked, the pro-osteogenic effect was suppressed. Additionally, compared with exosomes derived from BMDMs (BMDM-EXOs), MS-BMDM-EXOs exhibited a stronger ability to enhance BMSCs osteogenesis. At in vivo, mechanical force-induced alveolar bone formation was impaired during OTM when exosomes were blocked, and MS-BMDM-EXOs were more effective in promoting alveolar bone formation than BMDM-EXOs. Further proteomic analysis revealed that ubiquitin carboxyl-terminal hydrolase isozyme L3 (UCHL3) was enriched in MS-BMDM-EXOs compared with BMDM-EXOs. We went on to show that BMSCs osteogenesis and mechanical force-induced bone formation were impaired when UCHL3 was inhibited. Furthermore, mothers against decapentaplegic homologue 1 (SMAD1) was identified as the target protein of UCHL3. At the mechanistic level, we showed that SMAD1 interacted with UCHL3 in BMSCs and was downregulated when UCHL3 was suppressed. Consistently, overexpression of SMAD1 rescued the adverse effect of inhibiting UCHL3 on BMSCs osteogenesis. CONCLUSIONS: This study suggests that mechanical force-induced macrophage-derived exosomal UCHL3 promotes BMSCs osteogenesis by targeting SMAD1, thereby promoting alveolar bone formation during OTM.


Asunto(s)
Células Madre Mesenquimatosas , MicroARNs , Proteína Smad1 , Ubiquitina Tiolesterasa , Diferenciación Celular/fisiología , Macrófagos/metabolismo , Células Madre Mesenquimatosas/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Osteogénesis , Proteómica , Ubiquitina Tiolesterasa/metabolismo , Proteína Smad1/metabolismo
7.
BMC Med Educ ; 23(1): 315, 2023 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-37149587

RESUMEN

INTRODUCTION: Clinical practice of dentistry entails the use of indirect vision using a dental mirror. The Mirrosistant is a device that helps dental students become proficient with use of indirect vision mirror operation. This study aimed to explore the role of the Mirrosistant on students' performance with the virtual simulation dental training system. MATERIALS AND METHODS: A total of 72 dental students were equally assigned to the Control group and the Experimental group. Subsequently, Mirrosistant was used to conduct a series of mirror training exercises in the Experimental group. The training consisted of tracing the edge and filling in the blank of the prescribed shape, as well as preparing the specified figure on raw eggs using indirect vision via Mirrosistant. Next, both groups were examined using the SIMODONT system, a virtual reality dental trainer, for mirror operation. In addition, a five-point Likert scale questionnaire was used to assess student feedback by using Mirrosistant. RESULTS: The mirror operation examination conducted by the SIMODONT system revealed that mirror training using Mirrosistant had statistically improved students' performances (score: 80.42 ± 6.43 vs. 69.89 ± 15.98, P = 0.0005) and shorten their performance time of mirror operation (time of seconds: 243.28 ± 132.83 vs. 328.53 ± 111.89, P = 0.0013). Furthermore, the questionnaire survey indicated that the participants had positive attitudes toward the mirror training using Mirrosistant. Most students believed that the mirror training device could improve their perceptions of direction and distance, as well as their sensations of dental operation and dental fulcrum. CONCLUSION: Mirror training using Mirrosistant can enhance dental students' mirror perceptual and operational skills on virtual simulation dental training system.


Asunto(s)
Entrenamiento Simulado , Realidad Virtual , Humanos , Estudiantes de Odontología , Interfaz Usuario-Computador , Competencia Clínica , Simulación por Computador
8.
BMC Med Educ ; 23(1): 848, 2023 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-37946163

RESUMEN

INTRODUCTION: Oral histopathology is a bridge course connecting oral basic medicine and clinical dentistry. However, the application of outcomes-based education via flipped classroom (FC) in oral histopathology has not been well explored. This study has assessed the efficacy of outcomes-based education via FC in undergraduate oral histopathology module learning in Nanjing Medical University of China. MATERIALS AND METHODS: A total of 214 third-year students were enrolled and assigned to the FC group of the batch 2022-23 (n = 110) and the traditional classroom (TC) group of the batch 2021-22 (n = 104) to participate the oral histopathology sessions respectively in the study. The FC group were required to preview the online course materials pre-class, followed by in-class quizz, in-class interactive group discussion, and slides microscopic observation. The outcomes-based formative and summative assessments for FC were designed. The TC group attended traditional laboratory class for the same glass slides microscopic observation. In addition, a questionnaire was performed to investigate the satisfaction of learning. Along with this, the performances of FC group in written theory tests and oral histopathology slide tests were compared with TC group. RESULTS: Students in the FC group gained significantly final higher scores of the course than those in the TC group (score: 83.79 ± 11 vs. 76.73 ± 10.93, P<0.0001). Data from the student questionnaires indicated a preference for outcomes-based module education via FC. In the questionnaires, most students considered outcomes-based module education via FC to be beneficial to learning motivation, knowledge comprehension, critical thinking and teamwork. FC group had a higher level of satisfaction with oral histopathology teaching than TC group (satisfaction score: 4.599 ± 0.1027 vs. 4.423 ± 0.01366, P<0.01). CONCLUSION: An outcomes-based module education via FC has a promising effect on undergraduate oral histopathology education.


Asunto(s)
Aprendizaje , Estudiantes , Humanos , Pensamiento , Motivación , Encuestas y Cuestionarios , Aprendizaje Basado en Problemas , Curriculum
9.
Am J Orthod Dentofacial Orthop ; 163(4): 509-519, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37079283

RESUMEN

INTRODUCTION: This retrospective clinical study investigated the clinical changes of maxillary central incisor and alveolar bone in Class II Division 2 nonextraction treatment with fixed appliances or clear aligners on the basis of cone-beam computed tomography. METHODS: Fifty-nine Chinese Han patients with similar demographic characteristics were collected from a conventional bracket group, a self-ligating bracket group, and a clear aligner group. All measurements about root resorption and alveolar bone thickness on the cone-beam computed tomography images were tested. Changes between pretreatment and posttreatment were evaluated by paired-sample t test. The variation among the 3 groups was compared by 1-way analysis of variance. RESULTS: The resistance center of the maxillary central incisor showed upward or forward movement, and the axial inclination was increased in 3 groups (P <0.0001). Root volume loss in the clear aligner group (23.68 ± 4.82 mm3) was significantly less than that in the fixed appliances group (28.24 ± 6.44 mm3 in the conventional bracket group, 28.17 ± 6.07 mm3 in the self-ligating bracket group) (P <0.05). All 3 groups showed a significant decrease in palatal alveolar bone and total bone thickness at all 3 levels at posttreatment. In contrast, labial bone thickness significantly increased except for crestal level l. Among the 3 groups, the clear aligner group had a prominent increase in labial bone thickness at the apical level (P = 0.0235). CONCLUSIONS: Clear aligner treatment for Class II Division 2 malocclusions could effectively reduce the incidence of fenestration and root resorption. Our findings will be beneficial to comprehensively understand the effectiveness of different appliances for Class II Division 2 malocclusions treatment.


Asunto(s)
Maloclusión Clase II de Angle , Aparatos Ortodóncicos Removibles , Resorción Radicular , Humanos , Incisivo/diagnóstico por imagen , Estudios Retrospectivos , Maloclusión Clase II de Angle/diagnóstico por imagen , Maloclusión Clase II de Angle/terapia , Aparatos Ortodóncicos Fijos , Tomografía Computarizada de Haz Cónico , Maxilar/diagnóstico por imagen
10.
Angew Chem Int Ed Engl ; 62(44): e202308761, 2023 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-37496129

RESUMEN

Enzymatic reactions can consume endogenous nutrients of tumors and produce cytotoxic species and are therefore promising tools for treating malignant tumors. Inspired by nature where enzymes are compartmentalized in membranes to achieve high reaction efficiency and separate biological processes with the environment, we develop liposomal nanoreactors that can perform enzymatic cascade reactions in the aqueous nanoconfinement of liposomes. The nanoreactors effectively inhibited tumor growth in vivo by consuming tumor nutrients (glucose and oxygen) and producing highly cytotoxic hydroxyl radicals (⋅OH). Co-compartmentalization of glucose oxidase (GOx) and horseradish peroxidase (HRP) in liposomes could increase local concentration of the intermediate product hydrogen peroxide (H2 O2 ) as well as the acidity due to the generation of gluconic acid by GOx. Both H2 O2 and acidity accelerate the second-step reaction by HRP, hence improving the overall efficiency of the cascade reaction. The biomimetic compartmentalization of enzymatic tandem reactions in biocompatible liposomes provides a promising direction for developing catalytic nanomedicines in antitumor therapy.


Asunto(s)
Antineoplásicos , Neoplasias , Humanos , Liposomas , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Glucosa Oxidasa/farmacología , Peroxidasa de Rábano Silvestre , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Nanotecnología , Peróxido de Hidrógeno/uso terapéutico
11.
Angew Chem Int Ed Engl ; 62(24): e202218768, 2023 06 12.
Artículo en Inglés | MEDLINE | ID: mdl-36890113

RESUMEN

Conventional photocages only respond to short wavelength light, which is a significant obstacle to developing efficient phototherapy in vivo. The development of photocages activated by near-infrared (NIR) light at wavelengths from 700 to 950 nm is important for in vivo studies but remains challenging. Herein, we describe the synthesis of a photocage based on a ruthenium (Ru) complex with NIR light-triggered photocleavage reaction. The commercial anticancer drug, tetrahydrocurcumin (THC), was coordinated to the RuII center to create the Ru-based photocage that is readily responsive to NIR light at 760 nm. The photocage inherited the anticancer properties of THC. As a proof-of-concept, we further engineered a self-assembled photocage-based nanoparticle system with amphiphilic block copolymers. Upon exposure to NIR light at 760 nm, the Ru complex-based photocages were released from the polymeric nanoparticles and efficiently inhibited tumor proliferation in vivo.


Asunto(s)
Nanopartículas , Neoplasias , Fotoquimioterapia , Rutenio , Humanos , Fototerapia , Neoplasias/tratamiento farmacológico , Polímeros/uso terapéutico , Nanopartículas/uso terapéutico
12.
Small ; 18(27): e2201672, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35665442

RESUMEN

It is challenging to treat multidrug-resistant tumors because such tumors are resistant to a broad spectrum of structurally and functionally unrelated drugs. Herein, treatment of multidrug-resistant tumors using red-light-responsive metallopolymer nanocarriers that are conjugated with the anticancer drug chlorambucil (CHL) and encapsulated with the anticancer drug doxorubicin (DOX) is reported. An amphiphilic metallopolymer PolyRuCHL that contains a poly(ethylene glycol) (PEG) block and a red-light-responsive ruthenium (Ru)-containing block is synthesized. Chlorambucil is covalently conjugated to the Ru moieties of PolyRuCHL. Encapsulation of DOX into PolyRuCHL in an aqueous solution results in DOX@PolyRuCHL micelles. The DOX@PolyRuCHL micelles are efficiently taken up by the multidrug-resistant breast cancer cell line MCF-7R and which carries DOX into the cells. Free DOX, without the nanocarriers, is not taken up by MCF-7R or pumped out of MCF-7R via P-glycoproteins. Red light irradiation of DOX@PolyRuCHL micelles triggers the release of chlorambucil-conjugated Ru moieties and DOX. Both act synergistically to inhibit the growth of multidrug-resistant cancer cells. Furthermore, the inhibition of the growth of multidrug-resistant tumors in a mouse model using DOX@PolyRuCHL micelles is demonstrated. The design of red-light-responsive metallopolymer nanocarriers with both conjugated and encapsulated drugs opens up an avenue for photoactivated chemotherapy against multidrug-resistant tumors.


Asunto(s)
Antineoplásicos , Rutenio , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Clorambucilo/farmacología , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Portadores de Fármacos/farmacología , Resistencia a Múltiples Medicamentos , Resistencia a Antineoplásicos , Humanos , Ratones , Micelas , Fototerapia , Polietilenglicoles , Polímeros/farmacología
13.
Small ; 18(52): e2205461, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36366920

RESUMEN

Metallodrugs are widely used in cancer treatment. The modification of metallodrugs with polyethylene glycol (PEGylation) prolongs blood circulation and improves drug accumulation in tumors; it represents a general strategy for drug delivery. However, PEGylation hinders cellular internalization and tumor penetration, which reduce therapeutic efficacy. Herein, the red-light-enhanced cellular internalization and tumor penetration of a PEGylated anticancer agent, PEGylated Ru complex (Ru-PEG), are reported upon. Ru-PEG contains a red-light-cleavable PEG ligand, anticancer Ru complex moiety, and fluorescent pyrene group for imaging and self-assembly. Ru-PEG self-assembles into vesicles that circulate in the bloodstream and accumulate in the tumors. Red-light irradiation induces dePEGylation and changes the Ru-PEG vesicles to large compound micelles with smaller diameters and higher zeta potentials, which enhance tumor penetration and cellular internalization. Red-light irradiation also generates intracellular 1 O2 , which induces the death of cancer cells. This work presents a new strategy to enhance the cellular internalization and tumor penetration of anticancer agents for efficient phototherapy.


Asunto(s)
Antineoplásicos , Fototerapia , Fototerapia/métodos , Sistemas de Liberación de Medicamentos/métodos , Luz , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Polietilenglicoles , Línea Celular Tumoral
14.
Biomacromolecules ; 23(4): 1733-1744, 2022 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-35107271

RESUMEN

The lack of selectivity between tumor and healthy cells, along with inefficient reactive oxygen species production in solid tumors, are two major impediments to the development of anticancer Ru complexes. The development of photoinduced combination therapy based on biodegradable polymers that can be light activated in the "therapeutic window" would be beneficial for enhancing the therapeutic efficacy of Ru complexes. Herein, a biodegradable Ru-containing polymer (poly(DCARu)) is developed, in which two different therapeutics (the drug and the Ru complex) are rationally integrated and then conjugated to a diblock copolymer (MPEG-b-PMCC) containing hydrophilic poly(ethylene glycol) and cyano-functionalized polycarbonate with good degradability and biocompatibility. The polymer self-assembles into micelles with high drug loading capacity, which can be efficiently internalized into tumor cells. Red light induces the generation of singlet oxygen and the release of anticancer drug-Ru complex conjugates from poly(DCARu) micelles, hence inhibiting tumor cell growth. Furthermore, the phototherapy of polymer micelles demonstrates remarkable inhibition of tumor growth in vivo. Meanwhile, polymer micelles exhibit good biocompatibility with blood and healthy tissues, which opens up opportunities for multitherapeutic agent delivery and enhanced phototherapy.


Asunto(s)
Antineoplásicos , Neoplasias , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Portadores de Fármacos , Humanos , Micelas , Neoplasias/tratamiento farmacológico , Fototerapia , Cemento de Policarboxilato , Polietilenglicoles/uso terapéutico , Polímeros
15.
Analyst ; 147(9): 1798-1802, 2022 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-35388840

RESUMEN

A CO probe with PEGylation is synthesized, achieving the detection of CO in pure water solution with high intensity color change and fluorescence enhancement. Importantly, this probe with high affinity to paper strips and low toxicity to living cells is successfully used for sensing CO in air and in living cells.


Asunto(s)
Monóxido de Carbono , Colorimetría , Colorantes Fluorescentes/toxicidad , Polietilenglicoles , Espectrometría de Fluorescencia , Agua
16.
J Fluoresc ; 32(4): 1435-1441, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35441923

RESUMEN

The combination of the dicarboxylate ligand of 2-aminoterephthalic acid (H2L), Cd(NO3)2·4H2O, and KNO3 under hydrothermal condition formed a fresh hetero-metallic coordination polymer, namely, [CdK2(L)2(H2O)4]n (1). The compound exhibited a high luminescence intensity at normal environment as well as high sensitivity and selectivity in the measurement of CS2. The effect of the fresh compound on childhood diabetes was investigated. A blood glucose monitor was utilized to assess the blood glucose level of the body after the addition of the compound. Moreover, the relative expression level of the insulin recipient on hepatocytes was assessed by real time RT-PCR.


Asunto(s)
Diabetes Mellitus , Luminiscencia , Glucemia , Niño , Humanos , Ligandos , Polímeros
17.
Int J Mol Sci ; 23(22)2022 Nov 19.
Artículo en Inglés | MEDLINE | ID: mdl-36430872

RESUMEN

Ethylene polymerization with bis(imino)pyridlyiron precatalysts generally produces linear polyethylene (PE) even with the presence of α-olefins because α-olefins are not incorporated into polymeric products. Interestingly, α-olefins, such as hexene-1 or butene-1, have been found to act as effective chain transfer agents in the ethylene polymerization promoted by nonsymmetrical bis(imino)pyridyliron complexes with modified methylalumoxane (MMAO), resulting in higher catalytic activities with higher amounts of polymers with lower molecular weights, and, more importantly, narrower molecular weight distributions of the resultant polyethylenes (PE). This phenomenon confirms the assistance of α-olefins in the chain-termination reaction of iron-initiated polymerization and regeneration of the active species for further polymerization. Besides higher activities of the catalytic system, the formation of linear PE with trans-vinylene terminal groups and lower molecular weights are explained. The observation will provide a new pathway for enhancing catalytic activity and improving the quality of polyethylenes obtained by regulation of molecular weights and molecular weight distribution.


Asunto(s)
Alquenos , Etilenos , Polimerizacion , Piridinas , Polietileno , Polímeros , Compuestos Ferrosos
18.
J Pathol ; 251(3): 323-335, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32418202

RESUMEN

The lymphatic system plays a crucial role in the maintenance of tissue fluid homeostasis and the immunological response to inflammation. The effects of lymphatic drainage dysfunction on periodontitis have not been well studied. Here we show that lymphatic vessel endothelial receptor 1 (LYVE1)+ /podoplanin (PDPN)+ lymphatic vessels (LVs) are increased in the periodontal tissues, with accumulation close to the alveolar bone surface, in two murine periodontitis models: rheumatoid arthritis (RA)-associated periodontitis and ligature-induced periodontitis. Further, PDPN+ /alpha-smooth muscle actin (αSMA)- lymphatic capillaries are increased, whereas PDPN+ /αSMA+ collecting LVs are decreased significantly in the inflamed periodontal tissues. Both mouse models of periodontitis have delayed lymph flow in periodontal tissues, increased TRAP-positive osteoclasts, and significant alveolar bone loss. Importantly, the local administration of adeno-associated virus for vascular endothelial growth factor C, the major growth factor that promotes lymphangiogenesis, increases the area and number of PDPN+ /αSMA+ collecting LVs, promotes local lymphatic drainage, and reduces alveolar bone loss in both models of periodontitis. Lastly, LYVE1+ /αSMA- lymphatic capillaries are increased, whereas LYVE1+ /αSMA+ collecting LVs are decreased significantly in gingival tissues of patients with chronic periodontitis compared with those of clinically healthy controls. Thus, our findings reveal an important role of local lymphatic drainage in periodontal inflammation-mediated alveolar bone loss. © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Asunto(s)
Pérdida de Hueso Alveolar/prevención & control , Proceso Alveolar/metabolismo , Periodontitis Crónica/terapia , Terapia Genética , Linfa/metabolismo , Vasos Linfáticos/metabolismo , Maxilar/metabolismo , Factor C de Crecimiento Endotelial Vascular/biosíntesis , Factor C de Crecimiento Endotelial Vascular/genética , Pérdida de Hueso Alveolar/genética , Pérdida de Hueso Alveolar/metabolismo , Pérdida de Hueso Alveolar/patología , Proceso Alveolar/patología , Animales , Estudios de Casos y Controles , Periodontitis Crónica/genética , Periodontitis Crónica/metabolismo , Periodontitis Crónica/patología , Modelos Animales de Enfermedad , Humanos , Vasos Linfáticos/patología , Masculino , Maxilar/patología , Ratones Endogámicos C57BL , Ratones Transgénicos , Osteoclastos/metabolismo , Osteoclastos/patología , Factor de Necrosis Tumoral alfa/genética
19.
J Cell Physiol ; 235(9): 5938-5950, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-31967324

RESUMEN

Retention after treatment and effective anchorage control are two essential factors in orthodontics. Our study aimed to explore the effects of fucoidan on orthodontic tooth movement (OTM) and the involvement of macrophages. We established a murine OTM model to test the effect of fucoidan administration. We found that mice injected with fucoidan had a deceleration in OTM and a higher bone mineral density. Moreover, fucoidan increased the proportion of F4/80+ CD206+ macrophages and promoted the messenger RNA expression of Arg-1, CD206, and IL-10 at both in vivo and in vitro levels. In addition, macrophages showed lower expression of TNF-α, IL-1ß, and IL-6 and a decrease in F4/80+ CD11c+ cells. Mechanistically, the level of phosphorylated STAT3 was elevated in unpolarized and restorative macrophages after treatment with fucoidan. Taken together, our findings suggest that fucoidan treatment inhibits OTM and enhances the stability of teeth after movement by promoting restorative macrophages through the STAT3 pathway.


Asunto(s)
Macrófagos/metabolismo , Polisacáridos/farmacología , Factor de Transcripción STAT3/genética , Anomalías Dentarias/tratamiento farmacológico , Animales , Densidad Ósea/genética , Polaridad Celular/genética , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Interleucina-10/genética , Activación de Macrófagos/efectos de los fármacos , Macrófagos/patología , Ratones , Osteoclastos/efectos de los fármacos , Anomalías Dentarias/genética , Anomalías Dentarias/patología , Técnicas de Movimiento Dental , Factor de Necrosis Tumoral alfa/genética
20.
J Cell Physiol ; 235(9): 5972-5984, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-31970784

RESUMEN

Mechanical force across sutures is able to promote suture osteogenesis. Orthodontic clinics often use this biological characteristic of sutures to treat congenital cranio-maxillofacial malformations. However, the underlying mechanisms still remain poorly understood. Craniofacial sutures provide a special growth source and support primary sites of osteogenesis. Here, we isolated rat sagittal suture cells (rSAGs), which had mesenchymal stem cell characteristics and differentiating abilities. Cells were then subjected to mechanical tension (5% elongation, 0.5 Hz; sinusoidal waveforms) showing that mechanical tension could enhance osteogenic differentiation but hardly affect proliferation of rSAGs. Besides, mechanical tension could increase Rho-associated kinase (ROCK) expression and enhance transcriptional coactivator with PDZ-binding motif (TAZ) nuclear translocation. Inhibiting ROCK expression could suppress tension-induced osteogenesis and block tension-induced upregulation of nuclear TAZ. In addition, our results indicated that TAZ had direct combination sites with runt-related transcription factor 2 (Runx2) in rSAGs, and knock-downed TAZ simultaneously decreased the expression of Runx2 no matter with or without mechanical tension. In summary, our findings demonstrated that the multipotency of rSAGs in vitro could give rise to early osteogenic differentiation under mechanical tension, which was mediated by ROCK-TAZ signal axis.


Asunto(s)
Subunidad alfa 1 del Factor de Unión al Sitio Principal/genética , Suturas Craneales/metabolismo , Péptidos y Proteínas de Señalización Intracelular/genética , Osteogénesis/genética , Transactivadores/genética , Quinasas Asociadas a rho/genética , Animales , Diferenciación Celular/genética , Suturas Craneales/crecimiento & desarrollo , Suturas Craneales/patología , Fenómenos Mecánicos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Ratas , Transducción de Señal/genética , Proteínas Coactivadoras Transcripcionales con Motivo de Unión a PDZ
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