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1.
Cell ; 187(14): 3690-3711.e19, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38838669

RESUMEN

Clonal hematopoiesis of indeterminate potential (CHIP) arises from aging-associated acquired mutations in hematopoietic progenitors, which display clonal expansion and produce phenotypically altered leukocytes. We associated CHIP-DNMT3A mutations with a higher prevalence of periodontitis and gingival inflammation among 4,946 community-dwelling adults. To model DNMT3A-driven CHIP, we used mice with the heterozygous loss-of-function mutation R878H, equivalent to the human hotspot mutation R882H. Partial transplantation with Dnmt3aR878H/+ bone marrow (BM) cells resulted in clonal expansion of mutant cells into both myeloid and lymphoid lineages and an elevated abundance of osteoclast precursors in the BM and osteoclastogenic macrophages in the periphery. DNMT3A-driven clonal hematopoiesis in recipient mice promoted naturally occurring periodontitis and aggravated experimentally induced periodontitis and arthritis, associated with enhanced osteoclastogenesis, IL-17-dependent inflammation and neutrophil responses, and impaired regulatory T cell immunosuppressive activity. DNMT3A-driven clonal hematopoiesis and, subsequently, periodontitis were suppressed by rapamycin treatment. DNMT3A-driven CHIP represents a treatable state of maladaptive hematopoiesis promoting inflammatory bone loss.


Asunto(s)
Hematopoyesis Clonal , ADN (Citosina-5-)-Metiltransferasas , ADN Metiltransferasa 3A , Periodontitis , Animales , ADN (Citosina-5-)-Metiltransferasas/metabolismo , ADN (Citosina-5-)-Metiltransferasas/genética , Ratones , Hematopoyesis Clonal/genética , Humanos , Periodontitis/genética , Periodontitis/patología , Mutación , Masculino , Femenino , Inflamación/genética , Inflamación/patología , Osteoclastos/metabolismo , Ratones Endogámicos C57BL , Adulto , Interleucina-17/metabolismo , Interleucina-17/genética , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Hematopoyesis/genética , Osteogénesis/genética , Células Madre Hematopoyéticas/metabolismo , Resorción Ósea/genética , Resorción Ósea/patología , Persona de Mediana Edad
2.
Cell ; 185(10): 1709-1727.e18, 2022 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-35483374

RESUMEN

Bone marrow (BM)-mediated trained innate immunity (TII) is a state of heightened immune responsiveness of hematopoietic stem and progenitor cells (HSPC) and their myeloid progeny. We show here that maladaptive BM-mediated TII underlies inflammatory comorbidities, as exemplified by the periodontitis-arthritis axis. Experimental-periodontitis-related systemic inflammation in mice induced epigenetic rewiring of HSPC and led to sustained enhancement of production of myeloid cells with increased inflammatory preparedness. The periodontitis-induced trained phenotype was transmissible by BM transplantation to naive recipients, which exhibited increased inflammatory responsiveness and disease severity when subjected to inflammatory arthritis. IL-1 signaling in HSPC was essential for their maladaptive training by periodontitis. Therefore, maladaptive innate immune training of myelopoiesis underlies inflammatory comorbidities and may be pharmacologically targeted to treat them via a holistic approach.


Asunto(s)
Artritis , Periodontitis , Animales , Células Madre Hematopoyéticas , Inmunidad Innata , Ratones , Mielopoyesis
3.
Nat Immunol ; 20(1): 40-49, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30455459

RESUMEN

Resolution of inflammation is essential for tissue homeostasis and represents a promising approach to inflammatory disorders. Here we found that developmental endothelial locus-1 (DEL-1), a secreted protein that inhibits leukocyte-endothelial adhesion and inflammation initiation, also functions as a non-redundant downstream effector in inflammation clearance. In human and mouse periodontitis, waning of inflammation was correlated with DEL-1 upregulation, whereas resolution of experimental periodontitis failed in DEL-1 deficiency. This concept was mechanistically substantiated in acute monosodium-urate-crystal-induced inflammation, where the pro-resolution function of DEL-1 was attributed to effective apoptotic neutrophil clearance (efferocytosis). DEL-1-mediated efferocytosis induced liver X receptor-dependent macrophage reprogramming to a pro-resolving phenotype and was required for optimal production of at least certain specific pro-resolving mediators. Experiments in transgenic mice with cell-specific overexpression of DEL-1 linked its anti-leukocyte-recruitment action to endothelial cell-derived DEL-1 and its efferocytic/pro-resolving action to macrophage-derived DEL-1. Thus, the compartmentalized expression of DEL-1 facilitates distinct homeostatic functions in an appropriate context that can be harnessed therapeutically.


Asunto(s)
Proteínas Portadoras/metabolismo , Inflamación/inmunología , Macrófagos/fisiología , Neutrófilos/inmunología , Periodontitis/inmunología , Adulto , Animales , Proteínas de Unión al Calcio , Proteínas Portadoras/genética , Moléculas de Adhesión Celular , Reprogramación Celular , Citocinas/metabolismo , Regulación de la Expresión Génica , Humanos , Inflamación/inducido químicamente , Péptidos y Proteínas de Señalización Intercelular , Células K562 , Receptores X del Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fagocitosis
4.
J Immunol ; 211(3): 453-461, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37306457

RESUMEN

A minimized version of complement factor H (FH), designated mini-FH, was previously engineered combining the N-terminal regulatory domains (short consensus repeat [SCR]1-4) and C-terminal host-surface recognition domains (SCR19-20) of the parent molecule. Mini-FH conferred enhanced protection, as compared with FH, in an ex vivo model of paroxysmal nocturnal hemoglobinuria driven by alternative pathway dysregulation. In the current study, we tested whether and how mini-FH could block another complement-mediated disease, namely periodontitis. In a mouse model of ligature-induced periodontitis (LIP), mini-FH inhibited periodontal inflammation and bone loss in wild-type mice. Although LIP-subjected C3-deficient mice are protected relative to wild-type littermates and exhibit only modest bone loss, mini-FH strikingly inhibited bone loss even in C3-deficient mice. However, mini-FH failed to inhibit ligature-induced bone loss in mice doubly deficient in C3 and CD11b. These findings indicate that mini-FH can inhibit experimental periodontitis even in a manner that is independent of its complement regulatory activity and is mediated by complement receptor 3 (CD11b/CD18). Consistent with this notion, a complement receptor 3-interacting recombinant FH segment that lacks complement regulatory activity (specifically encompassing SCRs 19 and 20; FH19-20) was also able to suppress bone loss in LIP-subjected C3-deficient mice. In conclusion, mini-FH appears to be a promising candidate therapeutic for periodontitis by virtue of its ability to suppress bone loss via mechanisms that both include and go beyond its complement regulatory activity.


Asunto(s)
Factor H de Complemento , Periodontitis , Ratones , Animales , Factor H de Complemento/metabolismo , Vía Alternativa del Complemento , Proteínas del Sistema Complemento , Receptores de Complemento
5.
Periodontol 2000 ; 89(1): 215-230, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35244943

RESUMEN

Periodontitis is bidirectionally associated with systemic inflammatory disorders. The prevalence and severity of this oral disease and linked comorbidities increases with aging. Here, we review two newly emerged concepts, trained innate immunity (TII) and clonal hematopoiesis of indeterminate potential (CHIP), which together support a potential hypothesis on how periodontitis affects and is affected by comorbidities and why the susceptibility to periodontitis and comorbidities increases with aging. Given that chronic diseases are largely triggered by the action of inflammatory immune cells, modulation of their bone marrow precursors, the hematopoietic stem and progenitor cells (HSPCs), may affect multiple disorders that emerge as comorbidities. Such alterations in HSPCs can be mediated by TII and/or CHIP, two non-mutually exclusive processes sharing a bias for enhanced myelopoiesis and production of innate immune cells with heightened proinflammatory potential. TII is a state of elevated immune responsiveness based on innate immune (epigenetic) memory. Systemic inflammation can initiate TII in the bone marrow via sustained rewiring of HSPCs, which thereby display a skewing toward the myeloid lineage, resulting in generation of hyper-reactive or "trained" myeloid cells. CHIP arises from aging-related somatic mutations in HSPCs, which confer a survival and proliferation advantage to the mutant HSPCs and give rise to an outsized fraction of hyper-inflammatory mutant myeloid cells in the circulation and tissues. This review discusses emerging evidence that supports the notion that TII and CHIP may underlie a causal and age-related association between periodontitis and comorbidities. A holistic mechanistic understanding of the periodontitis-systemic disease connection may offer novel diagnostic and therapeutic targets for treating inflammatory comorbidities.


Asunto(s)
Hematopoyesis Clonal , Periodontitis , Células Madre Hematopoyéticas , Humanos , Inmunidad Innata , Inflamación , Periodontitis/complicaciones
6.
FASEB J ; 34(10): 13726-13740, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32812255

RESUMEN

The hypoxia-inducible factor 1α (HIF-1α) is critically involved in tissue regeneration. Hence, the pharmacological prevention of HIF-1α degradation by prolyl hydroxylase (PHD) under normoxic conditions is emerging as a promising option in regenerative medicine. Using a mouse model of ligature-induced periodontitis and resolution, we tested the ability of an injectable hydrogel-formulated PHD inhibitor, 1,4-dihydrophenonthrolin-4-one-3-carboxylic acid (1,4-DPCA/hydrogel), to promote regeneration of alveolar bone lost owing to experimental periodontitis. Mice injected subcutaneously with 1,4-DPCA/hydrogel at the onset of periodontitis resolution displayed significantly increased gingival HIF-1α protein levels and bone regeneration, as compared to mice treated with vehicle control. The 1,4-DPCA/hydrogel-induced increase in bone regeneration was associated with elevated expression of osteogenic genes, decreased expression of pro-inflammatory cytokine genes, and increased abundance of FOXP3+ T regulatory (Treg) cells in the periodontal tissue. The enhancing effect of 1,4-DPCA/hydrogel on Treg cell accumulation and bone regeneration was reversed by AMD3100, an antagonist of the chemokine receptor CXCR4 that mediates Treg cell recruitment. In conclusion, the administration of 1,4-DPCA/hydrogel at the onset of periodontitis resolution promotes CXCR4-dependent accumulation of Treg cells and alveolar bone regeneration, suggesting a novel approach for regaining bone lost due to periodontitis.


Asunto(s)
Regeneración Ósea , Inhibidores Enzimáticos/uso terapéutico , Hidrogeles/uso terapéutico , Prolina Dioxigenasas del Factor Inducible por Hipoxia/antagonistas & inhibidores , Periodontitis/tratamiento farmacológico , Linfocitos T Reguladores/inmunología , Animales , Línea Celular , Células Cultivadas , Citocinas/metabolismo , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/química , Femenino , Factores de Transcripción Forkhead/metabolismo , Encía/metabolismo , Humanos , Hidrogeles/administración & dosificación , Hidrogeles/química , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Prolina Dioxigenasas del Factor Inducible por Hipoxia/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Osteogénesis , Linfocitos T Reguladores/fisiología
7.
Proteomics ; 20(3-4): e1900253, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31881116

RESUMEN

Understanding the progression of periodontal tissue destruction is at the forefront of periodontal research. The authors aimed to capture the dynamics of gingival tissue proteome during the initiation and progression of experimental (ligature-induced) periodontitis in mice. Pressure cycling technology (PCT), a recently developed platform that uses ultra-high pressure to disrupt tissues, is utilized to achieve efficient and reproducible protein extraction from ultra-small amounts of gingival tissues in combination with liquid chromatography-tandem mass spectrometry (MS). The MS data are processed using Progenesis QI and the regulated proteins are subjected to METACORE, STRING, and WebGestalt for functional enrichment analysis. A total of 1614 proteins with ≥2 peptides are quantified with an estimated protein false discovery rate of 0.06%. Unsupervised clustering analysis shows that the gingival tissue protein abundance is mainly dependent on the periodontitis progression stage. Gene ontology enrichment analysis reveals an overrepresentation in innate immune regulation (e.g., neutrophil-mediated immunity and antimicrobial peptides), signal transduction (e.g., integrin signaling), and homeostasis processes (e.g., platelet activation and aggregation). In conclusion, a PCT-assisted label-free quantitative proteomics workflow that allowed cataloging the deepest gingival tissue proteome on a rapid timescale and provided novel mechanistic insights into host perturbation during periodontitis progression is applied.


Asunto(s)
Encía/metabolismo , Periodontitis/metabolismo , Proteoma/metabolismo , Proteómica/métodos , Espectrometría de Masas en Tándem/métodos , Tecnología Odontológica/métodos , Animales , Cromatografía Liquida/métodos , Modelos Animales de Enfermedad , Ontología de Genes , Líquido del Surco Gingival/metabolismo , Humanos , Ligadura/efectos adversos , Ratones Endogámicos C57BL , Periodontitis/etiología , Periodontitis/genética , Presión , Mapas de Interacción de Proteínas , Proteoma/genética
8.
J Proteome Res ; 17(9): 3153-3175, 2018 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-30111112

RESUMEN

Periodontitis is a prevalent chronic inflammatory disease associated with dysbiosis. Although complement inhibition has been successfully used to treat periodontitis in animal models, studies globally analyzing inflamed tissue proteins to glean insight into possible mechanisms of action are missing. Using quantitative shotgun proteomics, we aimed to investigate differences in composition of inflammatory gingival tissue exudate ("gingival crevicular fluid"; GCF), before and after local administration of an inhibitor of the central complement component, C3, in nonhuman primates. The C3 inhibitor, Cp40 (also known as AMY-101) was administered locally in the maxillary gingival tissue of cynomolgus monkeys with established periodontitis, either once a week (1×-treatment; n = 5 animals) or three times per week (3×-treatment; n = 10 animals), for 6 weeks followed by another 6 weeks of observation in the absence of treatment. 45 GCF samples were processed for FASP digestion and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. Data were processed using the ProgenesisQI software. The statistical significance of differences between the groups was determined by RM-ANOVA, and a protein expression change was considered as a true regulation at >2-fold and p < 0.05. The human orthologues were subjected to Gene Ontology analyses using PANTHER. Data are available via ProteomeXchange with identifier PXD009502. 573 proteins with >2 peptides were longitudinally quantified. Both 3× and 1× administration of Cp40 resulted in significant down-regulation of dozens of proteins during the 6-week course of treatment as compared to baseline. Following drug withdrawal at 6 weeks, more than 50% of the down-regulated proteins showed increased levels at week 12. The top scored pathway was "complement activation, alternative pathway", and several proteins involved in this pathway were down-regulated at 6 weeks. We mapped the proteomic fingerprint changes in local tissue exudate of cynomolgus monkey periodontitis in response to C3 inhibition and identified the alternative pathway of complement activation and leukocyte degranulation as main targets, which are thus likely to play significant roles in periodontal disease pathogenesis. Label-free quantitative proteomics strategies utilizing GCF are powerful tools for the identification of treatment targets and providing insights into disease mechanisms.


Asunto(s)
Antiinflamatorios/farmacología , Complemento C3/antagonistas & inhibidores , Vía Alternativa del Complemento/efectos de los fármacos , Líquido del Surco Gingival/química , Péptidos Cíclicos/farmacología , Periodontitis/tratamiento farmacológico , Animales , Degranulación de la Célula/efectos de los fármacos , Degranulación de la Célula/inmunología , Cromatografía Liquida , Complemento C3/genética , Vía Alternativa del Complemento/genética , Modelos Animales de Enfermedad , Esquema de Medicación , Regulación de la Expresión Génica , Ontología de Genes , Encía/efectos de los fármacos , Encía/inmunología , Encía/patología , Líquido del Surco Gingival/efectos de los fármacos , Líquido del Surco Gingival/inmunología , Leucocitos/efectos de los fármacos , Leucocitos/inmunología , Leucocitos/patología , Macaca fascicularis , Anotación de Secuencia Molecular , Periodontitis/genética , Periodontitis/inmunología , Periodontitis/patología , Proteoma/clasificación , Proteoma/genética , Proteoma/inmunología , Espectrometría de Masas en Tándem
9.
Artif Organs ; 41(5): 461-469, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27925229

RESUMEN

The treatment of long-segment tracheal defect requires the transplantation of effective tracheal substitute, and the tissue-engineered trachea (TET) has been proposed as an ideal tracheal substitute. The major cause of the failure of segmental tracheal defect reconstruction by TET is airway collapse caused by the chondromalacia of TET cartilage. The key to maintain the TET structure is the regeneration of chondrocytes in cartilage, which can secrete plenty of cartilage matrices. To address the problem of the chondromalacia of TET cartilage, this study proposed an improved strategy. We designed a new cell sheet scaffold using the poly(lactic-co-glycolic acid) (PLGA) and poly(trimethylene carbonate) (PTMC) to make a porous membrane for seeding cells, and used the PLGA-PTMC cell-scaffold to pack the decellularized allogeneic trachea to construct a new type of TET. The TET was then implanted in the subcutaneous tissue for vascularization for 2 weeks. Orthotopic transplantation was then performed after implantation. The efficiency of the TET we designed was analyzed by histological examination and biomechanical analyses 4 weeks after surgery. Four weeks after surgery, both the number of chondrocytes and the amount of cartilage matrix were significantly higher than those contained in the traditional stem-cell-based TET. Besides, the coefficient of stiffness of TET was significantly larger than the traditional TET. This study provided a promising approach for the long-term functional reconstruction of long-segment tracheal defect, and the TET we designed had potential application prospects in the field of TET reconstruction.


Asunto(s)
Condrogénesis , Dioxanos/química , Trasplante de Células Madre Mesenquimatosas , Células Madre Mesenquimatosas/citología , Polímeros/química , Ingeniería de Tejidos/métodos , Andamios del Tejido/química , Tráquea/trasplante , Animales , Cartílago/citología , Cartílago/fisiología , Cartílago/ultraestructura , Células Cultivadas , Condrocitos/citología , Ácido Láctico/química , Trasplante de Células Madre Mesenquimatosas/métodos , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Conejos , Regeneración , Tráquea/lesiones , Tráquea/ultraestructura
10.
Int J Biol Macromol ; 269(Pt 1): 132005, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38777686

RESUMEN

To enhance the mechanics performance, sensitivity and response range of multi-responsive photonic films, herein, a facile method for fabricating multi-responsive films is demonstrated using the evaporative self-assembly of a mixture of grape skin red (GSR), cellulose nanocrystal (CNC), polyvinyl alcohol (PVA) and deep eutectic solvent (DES). The prepared materials exhibited excellent thermal stability, strain properties, solvent resistance, ultraviolet (UV) resistance and antioxidant activity. Compared to a pure PVA film, the presence of GSR strengthened the antioxidant property of the film by 240.1 % and provided excellent UV barrier capability. The additional cross-linking of DES and CNC promoted more efficient phase fusion, yielding a film strain of 41.5 %. The addition of hydrophilic compound GSR, wetting and swelling due to the DES and the surface inhomogeneity of the films rendered the multi-responsive films high sensitivity, wide response range and multi-cyclic stability in environments with varying pH and humidity. A sample application showed that a PVA/CNC/DES film has the potential to differentiate between fresh, sub-fresh and fully spoiled shrimps. The above results help in designing intelligent thin film materials that integrate antioxidant properties, which help in monitoring the changes in food freshness and food packaging.


Asunto(s)
Antioxidantes , Celulosa , Nanopartículas , Alcohol Polivinílico , Alcohol Polivinílico/química , Celulosa/química , Nanopartículas/química , Antioxidantes/química , Disolventes Eutécticos Profundos/química , Embalaje de Alimentos/métodos , Vitis/química , Análisis de los Alimentos/métodos , Concentración de Iones de Hidrógeno
11.
PeerJ ; 10: e13894, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36068865

RESUMEN

Plastic film mulching (PFM) affects the spatiotemporal distribution of soil moisture and temperature, which in turn affects cotton growth and the spatiotemporal distribution of canopy photosynthetically active radiation (PAR). Due to the spatial heterogeneity of soil moisture, temperature and limited monitoring methods, the issues such as relatively few sampling points and long sampling intervals in most existing studies prevent the accurate quantification of spatiotemporal changes in moisture and temperature along soil profile. To investigate the effects of PFM on spatiotemporal changes in soil moisture, temperature, and canopy PAR in cotton fields, two field trials of plastic film-mulched (M) and nonmulched (NM) cultivations were performed in 2018 and 2019. The grid method was used for the soil information continuous monitoring and multiple-time fixed-site canopy PAR monitoring during the duration of cotton growth. Two-year field trial data showed that, M cultivation increased soil moisture by approximately 13.6%-25% and increased temperature by 2-4 °C in the 0-50 cm soil layer before the first irrigation (June 20) and by 1-2 °C in the 70-110 cm soil layer, compared with NM cultivation. In addition, the temperature difference between the two treatments gradually decreased with the increase in irrigation and air temperature. The M treatment reached the peak PAR interception rate 10 days earlier than the NM treatment. In 2018 and 2019, the PAR peak value under the M treatment was 4.62% and 1.8% higher than that under the NM treatment, respectively, but the PAR interception rate was decreased rapidly in the late growth stage. Overall, PFM had an effect on soil moisture retention during the whole growth period and greatly increased the soil temperature before budding stage, thus promoted the early growth of cotton. Considering this, we suggest that the irrigation quota and frequency could be appropriately decreased in the case of plastic film mulching cultivation. For nonmulching cultivation, the irrigation quota and frequency should be increased, and it is necessary to take measures to improve the soil temperature before middle July.


Asunto(s)
Agricultura , Suelo , Agricultura/métodos , Plásticos , Temperatura , Agua/análisis
12.
Environ Int ; 164: 107276, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35537366

RESUMEN

Brown carbon (BrC)/water-soluble organic carbon (WSOC) plays a crucial role in glacier melting. A quantitative evaluation of the light absorption characteristics of WSOC on glacier melting is urgently needed, as the WSOC release from glaciers potentially affects the hydrological cycle, downstream ecological balance, and the global carbon cycle. In this work, the optical properties and composition of WSOC in surface snow/ice on four Tibetan Plateau (TP) glaciers were investigated using a three-dimensional fluorescence spectrometer and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry. The total light-absorption of WSOC in snow/ice at 250-400 nm (ultraviolet region) and 400-600 nm (visible region) accounted for about 60.42% and 27.17% of the light absorption by the total organics, respectively. Two protein-like substances (PRLIS), one humic-like substance (HULIS), and one undefined species of chromophores in snow/ice on the TP glacier surfaces were identified. The lignins and lipids were the main compounds in the TP glaciers and were presented as CHO and CHNO molecules, while CHNOS molecules were only observed in the southeast TP glacier. The light absorption capacity of WSOC in snow/ice was mainly affected by their oxidizing properties. PRLIS and undefined species were closely linked to microbial sources and the local environment of the glaciers (lignins and lipids), while HULIS was significantly affected by anthropogenic emissions (protein/amino sugars). Radiative forcing (RF)-induced by WSOC relative to black carbon were accounted for about 11.62 ± 12.07% and 8.40 ± 10.37% in surface snow and granular ice, respectively. The RF was estimated to be 1.14 and 6.36 W m-2 in surface snow and granular ice, respectively, during the melt season in the central TP glacier. These findings contribute to our understanding of WSOC's impact on glaciers and could serve as a baseline for WSOC research in cryospheric science.


Asunto(s)
Cubierta de Hielo , Nieve , Carbono/análisis , Monitoreo del Ambiente/métodos , Sustancias Húmicas/análisis , Cubierta de Hielo/química , Lignina , Lípidos , Tibet , Agua/análisis
13.
Environ Pollut ; 277: 116757, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33647804

RESUMEN

Estuarine sediment denitrification and anammox in response to increased nitrogen (N) loads remain poorly understood. In this study, we used N isotope tracer approach to investigate the spatial distribution of denitrification and anammox and identified the crucial controls on the partitioning of dinitrogen gas (N2) production along the Min River Estuary (MRE), a highly impacted estuary in southeast China. The results indicated that denitrification and anammox rates ranged from 10.5 to 70.7 nmol g-1 h-1 and from 0.44 to 4.31 nmol g-1 h-1, respectively. Relative contribution of anammox to N2 production (Ra) was in a range of 1.04-15.1%, tending to increase toward estuary mouth. Denitrification rates were significantly higher in upper (high N loads) than in lower estuary (low N loads), while anammox rates and Ra showed inverse distributions along the MRE. Wastewater discharge caused the N point pollution triggering denitrification but inhibiting anammox. The best predictor of the variations in denitrification rates was total nitrogen, whereas pH and NH4+ could explained the variations in anammox rates across the estuary. The crucial predictors for the partitioning of N2 production between denitrification and anammox were NH4+ and NOx-. These results suggest that the increase in human activities intensity can alter the partitioning of N2 production between denitrification and anammox, and the magnitude of this switch can be predicted by N loads in MRE and other highly impacted estuaries.


Asunto(s)
Estuarios , Nitrógeno , China , Desnitrificación , Humanos , Nitrógeno/análisis , Oxidación-Reducción , Ríos
14.
Acta Biomater ; 105: 56-67, 2020 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-31954189

RESUMEN

Cell therapy is a promising approach for ischemic tissue regeneration. However, high death rate of delivered cells under low oxygen condition, and poor cell retention in tissues largely limit the therapeutic efficacy. Using cell carriers with high oxygen preservation has potential to improve cell survival. To increase cell retention, cell carriers that can quickly solidify at 37 °C so as to efficiently immobilize the carriers and cells in the tissues are necessary. Yet there lacks cell carriers with these combined properties. In this work, we have developed a family of high oxygen preservation and fast gelation hydrogels based on N-isopropylacrylamide (NIPAAm) copolymers. The hydrogels were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization of NIPAAm, acrylate-oligolactide (AOLA), 2-hydroxyethyl methacrylate (HEMA), and methacrylate-poly(ethylene glycol)-perfluorooctane (MAPEGPFC). The hydrogel solutions exhibited sol-gel temperatures around room temperature and were flowable and injectable at 4°C. They can quickly solidify (≤6 s) at 37°C to form flexible gels. These hydrogels lost 9.4~29.4% of their mass after incubation in Dulbecco's Phosphate-Buffered Saline (DPBS) for 4 weeks. The hydrogels exhibited a greater oxygen partial pressure than DPBS after being transferred from a 21% O2 condition to a 1% O2 condition. When bone marrow mesenchymal stem cells (MSCs) were encapsulated in the hydrogels and cultured under 1% O2, the cells survived and proliferated during the 14-day culture period. In contrast, the cells experienced extensive death in the control hydrogel that had low oxygen preservation capability. The hydrogels possessed excellent biocompatibility. The final degradation products did not provoke cell death even when the concentration was as high as 15 mg/ml, and the hydrogel implantation did not induce substantial inflammation. These hydrogels are promising as cell carriers for cell transplantation into ischemic tissues. STATEMENT OF SIGNIFICANCE: Stem cell therapy for ischemic tissues experiences low therapeutic efficacy largely due to poor cell survival under low oxygen condition. Using cell carriers with high oxygen preservation capability has potential to improve cell survival. In this work, we have developed a family of hydrogels with this property. These hydrogels promoted the encapsulated stem cell survival and growth under low oxygen condition.


Asunto(s)
Hidrogeles/farmacología , Oxígeno/farmacología , Animales , Materiales Biocompatibles/farmacología , Muerte Celular/efectos de los fármacos , Hipoxia de la Célula/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , ADN/metabolismo , Módulo de Elasticidad , Hidrogeles/síntesis química , Hidrogeles/química , Ratones Endogámicos C57BL , Comunicación Paracrina/efectos de los fármacos , Polímeros/síntesis química , Polímeros/química , Espectroscopía de Protones por Resonancia Magnética , Ratas , Tejido Subcutáneo/efectos de los fármacos , Resistencia a la Tracción , Temperatura de Transición , Agua/química
15.
J Leukoc Biol ; 108(5): 1501-1514, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32421906

RESUMEN

ß2 Integrins mediate neutrophil-endothelial adhesion and recruitment of neutrophils to sites of inflammation. The diminished expression of ß2 integrins in patients with mutations in the ITGB2 (CD18) gene (leukocyte adhesion deficiency-Type 1; LAD1) results in few or no neutrophils in peripheral tissues. In the periodontium, neutrophil paucity is associated with up-regulation of IL-23 and IL-17, which drive inflammatory bone loss. Using a relevant mouse model, we investigated whether diminished efferocytosis (owing to neutrophil scarcity) is associated with LAD1 periodontitis pathogenesis and aimed to develop approaches to restore the missing efferocytosis signals. We first showed that CD18-/- mice phenocopied human LAD1 in terms of IL-23/IL-17-driven inflammatory bone loss. Ab-mediated blockade of c-Mer tyrosine kinase (Mer), a major efferocytic receptor, mimicked LAD1-associated up-regulation of gingival IL-23 and IL-17 mRNA expression in wild-type (WT) mice. Consistently, soluble Mer-Fc reversed the inhibitory effect of efferocytosis on IL-23 expression in LPS-activated Mϕs. Adoptive transfer of WT neutrophils to CD18-/- mice down-regulated IL-23 and IL-17 expression to normal levels, but not when CD18-/- mice were treated with blocking anti-Mer Ab. Synthetic agonist-induced activation of liver X receptors (LXR) and peroxisome proliferator-activated receptors (PPAR), which link efferocytosis to generation of homeostatic signals, inhibited the expression of IL-23 and IL-17 and favorably affected the bone levels of CD18-/- mice. Therefore, our data link diminished efferocytosis-associated signaling due to impaired neutrophil recruitment to dysregulation of the IL-23-IL-17 axis and, moreover, suggest LXR and PPAR as potential therapeutic targets for treating LAD1 periodontitis.


Asunto(s)
Homeostasis/inmunología , Síndrome de Deficiencia de Adhesión del Leucocito/inmunología , Receptores X del Hígado/inmunología , Periodontitis/inmunología , Periodoncio/inmunología , Receptores Activados del Proliferador del Peroxisoma/inmunología , Animales , Antígenos CD18/genética , Antígenos CD18/inmunología , Homeostasis/genética , Interleucina-17/genética , Interleucina-17/inmunología , Interleucina-23/genética , Interleucina-23/inmunología , Síndrome de Deficiencia de Adhesión del Leucocito/genética , Síndrome de Deficiencia de Adhesión del Leucocito/patología , Receptores X del Hígado/genética , Ratones , Ratones Noqueados , Periodontitis/genética , Periodontitis/patología , Periodoncio/patología , Receptores Activados del Proliferador del Peroxisoma/genética , ARN Mensajero/genética , ARN Mensajero/inmunología , Regulación hacia Arriba/inmunología , Tirosina Quinasa c-Mer/genética , Tirosina Quinasa c-Mer/inmunología
16.
Front Cell Infect Microbiol ; 10: 588155, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33117738

RESUMEN

Efforts to map gingival tissue proteomes and microbiomes have been hampered by lack of sufficient tissue extraction methods. The pressure cycling technology (PCT) is an emerging platform for reproducible tissue homogenisation and improved sequence retrieval coverage. Therefore, we employed PCT to characterise the proteome and microbiome profiles in healthy and diseased gingival tissue. Healthy and diseased contralateral gingival tissue samples (total n = 10) were collected from five systemically healthy individuals (51.6 ± 4.3 years) with generalised chronic periodontitis. The tissues were then lysed and digested using a Barocycler, proteins were prepared and submitted for mass spectrometric analysis and microbiome DNA for 16S rRNA profiling analysis. Overall, 1,366 human proteins were quantified (false discovery rate 0.22%), of which 69 proteins were differentially expressed (≥2 peptides and p < 0.05, 62 up, 7 down) in periodontally diseased sites, compared to healthy sites. These were primarily extracellular or vesicle-associated proteins, with functions in molecular transport. On the microbiome level, 362 species-level operational taxonomic units were identified. Of those, 14 predominant species accounted for >80% of the total relative abundance, whereas 11 proved to be significantly different between healthy and diseased sites. Among them, Treponema sp. HMT253 and Fusobacterium naviforme and were associated with disease sites and strongly interacted (r > 0.7) with 30 and 6 up-regulated proteins, respectively. Healthy-site associated strains Streptococcus vestibularis, Veillonella dispar, Selenomonas sp. HMT478 and Leptotrichia sp. HMT417 showed strong negative interactions (r < -0.7) with 31, 21, 9, and 18 up-regulated proteins, respectively. In contrast the down-regulated proteins did not show strong interactions with the regulated bacteria. The present study identified the proteomic and intra-tissue microbiome profile of human gingiva by employing a PCT-assisted workflow. This is the first report demonstrating the feasibility to analyse full proteome profiles of gingival tissues in both healthy and disease sites, while deciphering the tissue site-specific microbiome signatures.


Asunto(s)
Microbiota , Proteoma , Fusobacterium , Encía , Humanos , Proteómica , ARN Ribosómico 16S/genética , Streptococcus , Veillonella
17.
Sci Total Environ ; 665: 171-180, 2019 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-30772546

RESUMEN

Increasing attention has been paid to anaerobic ammonium oxidation (anammox) in river ecosystems due to their special role in the global nitrogen cycle from land to the ocean. This study have revealed the spatial patterns of anammox bacterial response to geographic characteristics and dam operation along the Yangtze River, using 15N tracers and molecular analyses of microbial communities in sediment samples over a 4300 km continuum. Here we found a significant temperature-related increase in anammox bacterial abundance and alpha diversity from mountainous area in the upper, fluvial plain area in the middle and lower reach, to the river mouth. In contrast, an opposite trend in anammox contribution to N2 production (ra) was observed down the Yangtze River due to enhanced denitrification induced by spatial heterogeneity of total organic carbon. Interestingly, the Three Gorges Dam resulted in an intensive erosion and thus a change from muddy to sandy sediments within 400 km downstream the dam, which readjusted the anammox community characterized with a decreased bacterial diversity and enhanced anammox contribution to nitrogen loss. Our study highlights the importance of natural and anthropogenic impacts on anammox bacterial community and function in a complex large river ecosystem.


Asunto(s)
Compuestos de Amonio/toxicidad , Monitoreo del Ambiente , Contaminantes Químicos del Agua/toxicidad , Bacterias , China , Desnitrificación , Ecosistema , Sedimentos Geológicos , Nitrógeno , Oxidación-Reducción , ARN Ribosómico 16S , Ríos/química , Microbiología del Agua
18.
Ann Thorac Surg ; 107(3): 921-928, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30403979

RESUMEN

BACKGROUND: The purpose of this study is to use 3-dimensional printing (3DP) polyetheretherketone (PEEK) implants for skeletal reconstructions after wide excision of chest wall. 3DP PEEK implants were expected to provide a better physiological simulation than traditional ones because of a closer elastic modulus to cortical bone and similar biomechanical properties. METHODS: Eighteen patients (mean age 44.5 years), comprising 6 males and 12 females, underwent adequate radical wide excision for tumors and chest wall reconstruction using 3DP PEEK implants. Surgical data, which include patient demographic characteristics, implant preparation parameters, and preoperative and postoperative pulmonary function test results, were collected and analyzed. RESULTS: Ten patients with rib tumors and 8 patients with sternum tumors were selected for the study. The mean chest wall defect size was 173.6 ± 151.5 cm2 (range, 55 to 625 cm2). The mean weight of a single 3DP PEEK rib and sternum was 28 g and 104 g, respectively. The flexural and tensile strength of PEEK implants were 141 ± 7 MPa and 89 ± 3 MPa, respectively. Preoperative and postoperative pulmonary function tests revealed that mean forced vital capacity was from 2.79 ± 0.68 L to 2.40 ± 0.70 L with a reduction of 14.0% (p < 0.001). No side effects were observed 6 to 12 months after the operation. CONCLUSIONS: These findings suggest that 3DP PEEK implant is a safe and effective alternative in the reconstruction of chest wall defects. The pulmonary function of the patient may be preserved effectively after surgery.


Asunto(s)
Cetonas , Polietilenglicoles , Impresión Tridimensional , Neoplasias Torácicas/cirugía , Pared Torácica/cirugía , Toracoplastia/métodos , Adolescente , Adulto , Anciano , Benzofenonas , Materiales Biocompatibles , Diseño Asistido por Computadora , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada Multidetector/métodos , Polímeros , Tomografía de Emisión de Positrones , Diseño de Prótesis , Estudios Retrospectivos , Neoplasias Torácicas/diagnóstico , Pared Torácica/diagnóstico por imagen , Adulto Joven
19.
Sci Rep ; 9(1): 6535, 2019 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-31024011

RESUMEN

A primary goal in the management of burn wounds is early wound closure. The use of skin allografts represents a lifesaving strategy for severe burn patients, but their ultimate rejection limits their potential efficacy and utility. IL-6 is a major pleiotropic cytokine which critically links innate and adaptive immune responses. Here, we devised anti-IL-6 receptor eluting gelatin methacryloyl (GelMA) biomaterials (GelMA/anti-IL-6), which were implanted at the interface between the wound beds and skin allografts. Our visible light crosslinked GelMA/anti-IL-6 immunomodulatory biomaterial (IMB) demonstrated a stable kinetic release profile of anti-IL-6. In addition, the incorporation of anti-IL-6 within the GelMA hydrogel had no effect on the mechanical properties of the hydrogels. Using a highly stringent skin transplant model, the GelMA/anti-IL-6 IMB almost doubled the survival of skin allografts. The use of GelMA/anti-IL-6 IMB was far superior to systemic anti-IL-6 receptor treatment in prolonging skin allograft survival. As compared to the untreated control group, skin from the GelMA/anti-IL-6 IMB group contained significantly fewer alloreactive T cells and macrophages. Interestingly, the environmental milieu of the draining lymph nodes (DLNs) of the mice implanted with the GelMA/anti-IL-6 IMB was also considerably less pro-inflammatory. The percentage of CD4+ IFNγ+ cells was much lower in the DLNs of the GelMA/anti-IL-6 IMB group in comparison to the GelMA group. These data highlight the importance of localized immune delivery in prolonging skin allograft survival and its potential utility in treating patients with severe burns.


Asunto(s)
Aloinjertos/efectos de los fármacos , Materiales Biocompatibles/farmacología , Supervivencia de Injerto/efectos de los fármacos , Factores Inmunológicos/farmacología , Interleucina-6/inmunología , Trasplante de Piel , Animales , Sistemas de Liberación de Medicamentos , Liberación de Fármacos , Femenino , Fibrosis , Gelatina/química , Supervivencia de Injerto/inmunología , Inflamación/patología , Ganglios Linfáticos/efectos de los fármacos , Ganglios Linfáticos/patología , Metacrilatos/química , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Porcinos , Linfocitos T/efectos de los fármacos , Adhesivos Tisulares/farmacología
20.
Zhongguo Fei Ai Za Zhi ; 21(4): 273-276, 2018 Apr 20.
Artículo en Zh | MEDLINE | ID: mdl-29587904

RESUMEN

Chest wall defect may be caused by many factors such as the resection of tumor and trauma, and the reconstruction of bone-defection is still the key point of thoracic surgery. With the development of material science, more and more new materials have been used in medical practice, which makes huge progress in the surgery of chest wall. However, none of these materials satisfy all the practical needs of the reconstruction. Recently, with the development of the capacity of computer, 3D-printing technology has been gradually used in clinical work, and the idea of individual treatment has been accepted by more and more people. The weakness of these materials may be solved by the new material and the application of individual treatment, which could also make great advance in chest wall surgery. This article will make a summary of the research on the reconstruction of chest wall.
.


Asunto(s)
Procedimientos de Cirugía Plástica/métodos , Neoplasias Torácicas/cirugía , Pared Torácica/cirugía , Animales , Materiales Biocompatibles/síntesis química , Materiales Biocompatibles/química , Humanos , Impresión Tridimensional , Procedimientos de Cirugía Plástica/instrumentación , Pared Torácica/trasplante
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