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1.
Mol Cell Biochem ; 479(4): 761-777, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37178376

RESUMEN

Saliva has emerged as a promising noninvasive biofluid for the diagnosis of oral and systemic diseases, including viral infections. During the coronavirus disease 2019 (COVID-19) pandemic, a growing number of studies focused on saliva-based detection of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Taking advantage of the WoS core collection (WoSCC) and CiteSpace, we retrieved 1021 articles related to saliva-based detection of SARS-CoV-2 and conducted a comprehensive bibliometric analysis. We analyzed countries, institutions, authors, cited authors, and cited journals to summarize their contribution and influence and analyzed keywords to explore research hotspots and trends. From 2020 to 2021, research focused on viral transmission via saliva and verification of saliva as a reliable specimen, whereas from 2021 to the present, the focus of research has switched to saliva-based biosensors for SARS-CoV-2 detection. By far, saliva has been verified as a reliable specimen for SARS-CoV-2 detection, although a standardized procedure for saliva sampling and processing is needed. Studies on saliva-based detection of SARS-CoV-2 will promote the development of saliva-based diagnostics and biosensors for viral detection. Collectively, our findings could provide valuable information to help scientists perceive the basic knowledge landscapes on saliva-based detection of SARS-CoV-2, the past and current research hotspots, and future opportunities.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/diagnóstico , COVID-19/epidemiología , Saliva , Prueba de COVID-19 , Bibliometría
2.
Nat Mater ; 21(12): 1426-1433, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36357686

RESUMEN

The ability to impart multiple covarying properties into a single material represents a grand challenge in manufacturing. In the design of block copolymers (BCPs) for directed self-assembly and nanolithography, materials often balance orthogonal properties to meet constraints related to processing, structure and defectivity. Although iterative synthesis strategies deliver BCPs with attractive properties, identifying materials with all the required attributes has been difficult. Here we report a high-throughput synthesis and characterization platform for the discovery and optimization of BCPs with A-block-(B-random-C) architectures for lithographic patterning in semiconductor manufacturing. Starting from a parent BCP and using thiol-epoxy 'click' chemistry, we synthesize a library of BCPs that cover a large and complex parameter space. This allows us to readily identify feature-size-dependent BCP chemistries for 8-20-nm-pitch patterns. These blocks have similar surface energies for directed self-assembly, and control over the segregation strength to optimize the structure (favoured at higher segregation strengths) and defectivity (favoured at lower segregation strengths).


Asunto(s)
Polímeros , Proyectos de Investigación , Semiconductores , Compuestos de Sulfhidrilo
3.
Chem Soc Rev ; 51(18): 7883-7943, 2022 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-35993776

RESUMEN

Calcium carbonate (CaCO3) is an important inorganic mineral in biological and geological systems. Traditionally, it is widely used in plastics, papermaking, ink, building materials, textiles, cosmetics, and food. Over the last decade, there has been rapid development in the controlled synthesis and surface modification of CaCO3, the stabilization of amorphous CaCO3 (ACC), and CaCO3-based nanostructured materials. In this review, the controlled synthesis of CaCO3 is first examined, including Ca2+-CO32- systems, solid-liquid-gas carbonation, water-in-oil reverse emulsions, and biomineralization. Advancing insights into the nucleation and crystallization of CaCO3 have led to the development of efficient routes towards the controlled synthesis of CaCO3 with specific sizes, morphologies, and polymorphs. Recently-developed surface modification methods of CaCO3 include organic and inorganic modifications, as well as intensified surface reactions. The resultant CaCO3 can then be further engineered via template-induced biomineralization and layer-by-layer assembly into porous, hollow, or core-shell organic-inorganic nanocomposites. The introduction of CaCO3 into nanostructured materials has led to a significant improvement in the mechanical, optical, magnetic, and catalytic properties of such materials, with the resultant CaCO3-based nanostructured materials showing great potential for use in biomaterials and biomedicine, environmental remediation, and energy production and storage. The influences that the preparation conditions and additives have on ACC preparation and stabilization are also discussed. Studies indicate that ACC can be used to construct environmentally-friendly hybrid films, supramolecular hydrogels, and drug vehicles. Finally, the existing challenges and future directions of the controlled synthesis and functionalization of CaCO3 and its expanding applications are highlighted.


Asunto(s)
Carbonato de Calcio , Nanocompuestos , Materiales Biocompatibles , Carbonato de Calcio/química , Emulsiones , Hidrogeles , Minerales , Plásticos , Agua/química
4.
Clin Oral Investig ; 24(11): 4133-4142, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32356209

RESUMEN

OBJECTIVE: The aim of this study was to predict the risk of lingual plate fracture during mandibular third molar (M3) extraction. MATERIALS AND METHODS: Cone beam computed tomography (CBCT) data from 264 mandibular M3s (erupted and impacted) from 264 patients (104 males and 160 females; age range, 17-75 years) were retrospectively analyzed. Lingual plate thicknesses at the levels of the mid-root and root apex of the M3s were measured and defined as "thicker" (bone thicker than 1 mm), "thinner" (bone thinner than 1 mm), or "perforated" (bone perforated by the M3 root). These measurements were correlated with potential risk factors for thinner and perforated lingual plates: tooth position of the mandibular M3, morphology of the lingual plate, and patient characteristics (age and sex). RESULTS: The mean thickness of the lingual plate was 1.49 ± 1.38 mm at the mid-root of the M3s, and 2.35 ± 2.03 mm at the root apex. Multivariate regression analyses revealed that mesioangularly and horizontally impacted M3s were significantly associated with thinner and perforated lingual plates at the mid-root (P < 0.001), whereas the M3s in infra-occlusion positions (in infra-occlusion when compared with the adjacent second molar) had thinner lingual bone at the root apex (P = 0.022 and P = 0.027, depending on the level of impaction). Female patients were less likely to have lingual plate perforation (P = 0.036). CONCLUSIONS: Mesioangulation, infra-occlusion, and male sex were risk factors for lingual plate fracture. CLINICAL RELEVANCE: When the risk of lingual plate fracture is high, a sufficiently large flap, osteotomy, and tooth section by bur or piezosurgery are recommended to create a good operative field and avoid excessive pressure on the lingual plate.


Asunto(s)
Tercer Molar , Diente Impactado , Adolescente , Adulto , Anciano , Tomografía Computarizada de Haz Cónico , Femenino , Humanos , Masculino , Mandíbula , Persona de Mediana Edad , Diente Molar , Tercer Molar/diagnóstico por imagen , Tercer Molar/cirugía , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
5.
BMC Musculoskelet Disord ; 20(1): 246, 2019 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-31122219

RESUMEN

BACKGROUND: Managing with diabetic foot osteomyelitis (DFO) is challenging. Even after infective bone resection and thorough debridement, DFO is still difficult to cure and has a high recurrence rate. This retrospective study aims to compare the outcomes of two treatment methods, infected bone resection combined with adjuvant antibiotic-impregnated calcium sulfate and infected bone resection alone, for the treatment of diabetic foot osteomyelitis. METHODS: Between 2015 to 2017, 48 limbs (46 patients) with DFO met the criteria were included for assessment. 20 limbs (18 patients) were included in the calcium sulfate group (the CS group) in which vancomycin and/or gentamicin-impregnated calcium sulfate was used as an adjuvant after infected bone resection while 28 limbs (28 patients) as the control group were undergone infected bone resection only. Systemic antibiotics, postoperative wound care and offloading were continued to be applied following surgery in both groups. The time to healing, healing rate, recurrence rate and amputation rate were compared between the two groups. RESULTS: In total, 90% (18/20) limbs in the CS group as compared to 78.6% (22/28) infected limbs in the control group went to heal (P = 0.513). The Mean time to healing was 13.3 weeks in the CS group and 11.2 weeks in control group (P = 0.132). Osteomyelitis recurrence rate was 0% (0/18) in the CS group and 36.4% (8/22) in the control group (P = 0.014). Postoperative leakage in calcium sulfate group was 30.0% (6/20) with a mean duration of 8.5 weeks. Amputation rate in the control group was 7.1% (2/28) compared to 0% (0/20) in the CS group (P = 0.153). CONCLUSIONS: Antibiotic-impregnated calcium sulfate as an adjuvant prevents the recurrence of DFO but cannot improve the healing rate, reduce the postoperative amputation rate or shorten the time to healing. Prolonged postoperative leakage as the most common complication can be managed with regular dressing. LEVEL OF EVIDENCE: III, Retrospective Comparative Study.


Asunto(s)
Antibacterianos/administración & dosificación , Sustitutos de Huesos/administración & dosificación , Pie Diabético/terapia , Osteomielitis/terapia , Osteotomía/métodos , Complicaciones Posoperatorias/epidemiología , Adulto , Anciano , Anciano de 80 o más Años , Amputación Quirúrgica/estadística & datos numéricos , Sustitutos de Huesos/química , Sulfato de Calcio/administración & dosificación , Terapia Combinada , Pie Diabético/complicaciones , Femenino , Pie , Humanos , Masculino , Persona de Mediana Edad , Osteomielitis/etiología , Osteotomía/efectos adversos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/terapia , Recurrencia , Estudios Retrospectivos , Factores de Tiempo , Cicatrización de Heridas/efectos de los fármacos
6.
Chemistry ; 24(59): 15840-15851, 2018 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-30088300

RESUMEN

Three new polyether-tethered bisquinolinium dimers (3 a-c) were synthesized, and their binding affinities, selectivities, and thermal stabilization towards dimeric G-quadruplex DNA (G2T1) in human telomeric regions were studied. The bisquinolinium dimer with a medium-length polyether linker (3 b) showed 30-425-fold higher binding affinity and selectivity towards antiparallel G2T1 than towards monomeric quadruplexes, which included human telomeric monomeric G-quadruplexes (G1), c-kit 1, c-kit 2, and c-myc. In addition, compound 3 b induced the formation of quadruplexes and displayed the highest level of thermal stabilization (ΔTm >28.1 °C) among all reported multimeric G-quadruplex binders. Compound 3 b also displayed a higher selectivity towards antiparallel G2T1 than monomer 360 A and bisquinolinium dimers 3 a and c. In contrast with our recent research on the analogous berberine dimer 1 b and dinickel-salphen complex 2 c, polyether linkers and their monomeric G-quadruplex binders in these dimeric G-quadruplex binders play a crucial role in regulating the binding affinities, selectivities, and thermal stabilization towards G2T1. More interestingly, these dimeric G-quadruplex compounds bind through end-stacking with the two adjacent G-quadruplex units in G2T1, and they showed high selectivity towards antiparallel G2T1 rather than mixed-type G2T1. In addition, compound 3 b, which displayed high selectivity towards antiparallel G2T1, showed strong telomerase inhibition and potent anticancer activities against HeLa and MCF-7 cells.


Asunto(s)
Antineoplásicos/síntesis química , G-Cuádruplex , Compuestos de Quinolinio/síntesis química , Telómero/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Secuencia de Bases , Berberina/química , Dimerización , Éteres/química , Células HeLa , Humanos , Células MCF-7 , Conformación de Ácido Nucleico , Fenilendiaminas/química , Polímeros/química , Compuestos de Quinolinio/metabolismo , Compuestos de Quinolinio/farmacología , Relación Estructura-Actividad , Telómero/metabolismo , Termodinámica
7.
J Biol Chem ; 289(29): 20359-69, 2014 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-24898252

RESUMEN

Aminoacyl-tRNA synthetases are an ancient enzyme family that specifically charges tRNA molecules with cognate amino acids for protein synthesis. Glycyl-tRNA synthetase (GlyRS) is one of the most intriguing aminoacyl-tRNA synthetases due to its divergent quaternary structure and abnormal charging properties. In the past decade, mutations of human GlyRS (hGlyRS) were also found to be associated with Charcot-Marie-Tooth disease. However, the mechanisms of traditional and alternative functions of hGlyRS are poorly understood due to a lack of studies at the molecular basis. In this study we report crystal structures of wild type and mutant hGlyRS in complex with tRNA and with small substrates and describe the molecular details of enzymatic recognition of the key tRNA identity elements in the acceptor stem and the anticodon loop. The cocrystal structures suggest that insertions 1 and 3 work together with the active site in a cooperative manner to facilitate efficient substrate binding. Both the enzyme and tRNA molecules undergo significant conformational changes during glycylation. A working model of multiple conformations for hGlyRS catalysis is proposed based on the crystallographic and biochemical studies. This study provides insights into the catalytic pathway of hGlyRS and may also contribute to our understanding of Charcot-Marie-Tooth disease.


Asunto(s)
Glicina-ARNt Ligasa/química , ARN de Transferencia de Glicerina/química , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Dominio Catalítico/genética , Enfermedad de Charcot-Marie-Tooth/enzimología , Enfermedad de Charcot-Marie-Tooth/genética , Cristalografía por Rayos X , Glicina-ARNt Ligasa/genética , Glicina-ARNt Ligasa/metabolismo , Glicosilación , Células HeLa , Humanos , Sustancias Macromoleculares/química , Sustancias Macromoleculares/metabolismo , Modelos Moleculares , Mutagénesis Insercional , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Conformación de Ácido Nucleico , Conformación Proteica , ARN de Transferencia de Glicerina/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Thermus thermophilus/enzimología , Thermus thermophilus/genética
8.
Bioorg Med Chem Lett ; 25(4): 745-8, 2015 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-25616903

RESUMEN

A rigid bis(choloyl) conjugate functionalized with guanidino groups was synthesized and fully characterized on the basis of NMR ((1)H and (13)C) and ESI MS (LR and HR) data. Its transmembrane ionophoric activity across egg-yolk l-α-phosphatidylcholine-based liposomal membranes was investigated by means of chloride ion selective electrode technique and pH discharge assay. The data indicate that under the assay conditions, this conjugate was capable of promoting the transport of anions, presumably via a cation/anion symport process. A Hill analysis reveals that two molecules of this compound are assembled into the transport-active species.


Asunto(s)
Ácidos Cólicos/química , Ácidos Cólicos/farmacología , Guanidina/química , Guanidina/farmacología , Ionóforos/química , Ionóforos/farmacología , Cationes/química , Cloruros/química , Concentración de Iones de Hidrógeno , Transporte Iónico/efectos de los fármacos , Liposomas/química , Fosfatidilcolinas/química
9.
Bioorg Med Chem Lett ; 24(13): 2859-62, 2014 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-24835981

RESUMEN

A squaramide-linked bis(choloyl) conjugate was synthesized and fully characterized on the basis of NMR ((1)H and (13)C) and ESI MS (LR and HR) data. Fluorescence and chloride ion selective electrode assays indicate that this compound exhibits potent ionophoric activity across egg-yolk L-α-phosphatidylcholine-based liposomal membranes, presumably via an anion-modulating anion-cation co-transport/symport process. A Hill analysis reveals that three molecules of this compound are assembled into the transport-active species.


Asunto(s)
Amidas/química , Ácidos Cólicos/química , Ionóforos/química , Liposomas/química , Animales , Pollos , Yema de Huevo/química , Ionóforos/síntesis química , Estructura Molecular
10.
BMC Vet Res ; 10: 2, 2014 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-24386990

RESUMEN

BACKGROUND: Toll-like receptor (TLR) agonists reportedly have potent antiviral and antitumor activities and may be a new kind of adjuvant for enhancing immune efficacy. Resiquimod (R848) is an imidazoquinoline compound with potent antiviral activity and functions through the TLR7/TLR8 MyD88-dependent signaling pathway. Polyinosinic-polycytidylic acid [poly(I:C)] is a synthetic analog of double-stranded RNA that induces the production of pro-inflammatory cytokines by the activation of NF-κB through TLR3. This study investigated the potential of R848 and poly(I:C) as an adjuvant 146S foot-and-mouth disease virus (FMDV) vaccine formulated with aluminum hydroxide (Al(OH)3). RESULTS: Antibody titers to FMDV and CD8+ T cells were markedly enhanced in mice immunized to 146S FMDV + Al(OH)3 + R848 + poly(I:C) compared with mice immunized to FMDV + ISA206. IFN-γ secretion substantially increased compared with IL-4 secretion by splenic T cells stimulated with FMDV antigens in vitro, suggesting that R848, poly(I:C), and with Al(OH)3 together biased the immune response toward a Th1-type direction. CONCLUSIONS: These results indicated that the R848 and poly(I:C) together with Al(OH)3 enhanced humoral and cellular immune responses to immunization with 146S FMDV antigens. Thus, this new vaccine formulation can be used for FMDV prevention.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Hidróxido de Aluminio/farmacología , Fiebre Aftosa/prevención & control , Imidazoles/farmacología , Poli I-C/farmacología , Vacunas Virales/inmunología , Adyuvantes Inmunológicos/administración & dosificación , Hidróxido de Aluminio/administración & dosificación , Hidróxido de Aluminio/química , Animales , Anticuerpos Antivirales/sangre , Especificidad de Anticuerpos , Femenino , Fiebre Aftosa/inmunología , Imidazoles/administración & dosificación , Ratones , Ratones Endogámicos BALB C , Poli I-C/administración & dosificación , Bazo/citología , Bazo/efectos de los fármacos , Subgrupos de Linfocitos T , Vacunas Virales/administración & dosificación
11.
Adv Sci (Weinh) ; 11(5): e2302674, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38037309

RESUMEN

Developing biomaterials with antimicrobial and wound-healing activities for the treatment of wound infections remains challenging. Macrophages play non-negligible roles in healing infection-related wounds. In this study, a new sequential immunomodulatory approach is proposed to promote effective and rapid wound healing using a novel hybrid hydrogel dressing based on the immune characteristics of bacteria-associated wounds. The hydrogel dressing substrate is derived from a porcine dermal extracellular matrix (PADM) and loaded with a new class of bioactive glass nanoparticles (BGns) doped with copper (Cu) and zinc (Zn) ions (Cu-Zn BGns). This hybrid hydrogel demonstrates a controlled release of Cu2+ and Zn2+ and sequentially regulates the phenotypic transition of macrophages from M1 to M2 by alternately activating nucleotide-binding oligomerization domain (NOD) and inhibiting mitogen-activated protein kinases (MAPK) signaling pathways. Additionally, its dual-temporal bidirectional immunomodulatory function facilitates enhanced antibacterial activity and wound healing. Hence, this novel hydrogel is capable of safely and efficiently accelerating wound healing during infections. As such, the design strategy provides a new direction for exploring novel immunomodulatory biomaterials to address current clinical challenges related to the treatment of wound infections.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infección de Heridas , Animales , Porcinos , Cobre , Hidrogeles/química , Cicatrización de Heridas , Materiales Biocompatibles/química , Infección de Heridas/tratamiento farmacológico , Zinc
12.
Colloids Surf B Biointerfaces ; 230: 113523, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37634286

RESUMEN

Polyetheretherketone (PEEK) is being increasingly recognized as a highly promising polymer implant in orthopaedics due to its advantageous biocompatibility, favorable processability, and radiation resistance. Nonetheless, the long-term application of PEEK implants in vivo faces challenges due to unfavorable post-implantation inflammatory and immune reactions, which result in suboptimal osseointegration rates. Hence, biofunctionalizing the surface of PEEK implants emerges as a viable strategy to enhance osseointegration and increase the success rate. In this study, we developed a multifunctional PEEK implant through the in-situ incorporation of chitosan-coated bioactive glass nanoparticles (BGNs). This approach can impart immunomodulatory properties and enhance the potential for osseointegration. The resulting biofunctionalized PEEK material exhibited multiple beneficial effects. For instance, it facilitated M2 phenotypic polarization of macrophages, diminished the expression of inflammatory factors, and enhanced the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in vitro. Moreover, it exhibited an improved capacity for osseointegration when tested in vivo. The findings of the experiment highlighted the pivotal and complex role of the biofunctionalized PEEK implant in maintaining typical bone immunity and metabolism. The study proposes that the application of chitosan-BGNs presents a straightforward approach to developing multifunctional implants with the ability to promote biomineralization and immunomodulation, specifically tailored for orthopaedic applications.


Asunto(s)
Quitosano , Magnesio , Osteogénesis , Regeneración Ósea , Polietilenglicoles/farmacología , Diferenciación Celular
13.
Front Immunol ; 14: 1135096, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36911675

RESUMEN

Background/Objectives: Autoimmune pancreatitis (AIP) is a distinct form of pancreatic inflammatory disease that responds well to glucocorticoid therapy. Knowledge on AIP has rapidly evolved over the past two decades. Based on bibliometric analysis, this study aimed to assess the research status of AIP over the past two decades and determine the research focus and emerging topics. Methods: AIP-related publications published between January 1, 2002, and June 6, 2022, were retrieved from the Web of Science Core Collection. Bibliometric data were analyzed using HisCite, VOSviewer, CiteSpace, and bibliometrix package. Annual output, leading countries/regions, active institutions and authors, core journals and references, and keywords of AIP were evaluated. Results: Overall, 1,772 publications were retrieved from 501 journals by 6,767 authors from 63 countries/regions. Japan published articles on AIP the most (n=728, 41.1%), followed by the United States (n=336, 19%), Germany (n=147, 8.3%), China (n=127, 7%), and Italy (n=107, 6%). The top three most prolific authors were Terumi Kamisawa from Tokyo Metropolitan Komagome Hospital (n=117), Kazuichi Okazaki from Kansai Medical University (n=103), and Shigeyuki Kawa from Matsumoto Dental University (n=94). Pancreas was the most productive journal regarding AIP research (n=95), followed by the Journal of Gastroenterology (n=67), Internal Medicine (n=66), Pancreatology (n=63), and World Journal of Gastroenterology (n=62). "Diagnosis" was the most mentioned keyword. "Risk," "malignancy," "outcome," "22-gauge needle," and "fine-needle aspiration" were recognized as emerging topics. Conclusion: Japan was the leading country in AIP research. Research papers were mainly published in specialized journals. Diagnosis was the research focus. Long-term outcomes and pancreatic tissue acquisition were recognized as research frontiers for AIP.


Asunto(s)
Pancreatitis Autoinmune , Enfermedades Pancreáticas , Humanos , Páncreas , Bibliometría , China , Alemania
14.
Int J Pharm ; 635: 122767, 2023 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-36822342

RESUMEN

Type 2 diabetes mellitus (T2DM) is a complex metabolic disorder, which is ultimately treated by the insulin (INS). However, the subcutaneous (s. c.) injection of insulin solution faces the problems of pain and unsatisfactory patient compliance. In this study, the long-acting formulations of insulin are propsed to treat the T2DM and prevent the associated complications. The chitosan (CS) and/or branched polyethyleneimine (bPEI) nanoparticles (bPEI-INS NPs, CS-bPEI-INS NPs) were constructed to load insulin. The long -acting nanoparticles successfully achieved the sustained release of the INS in vitro and in vivo. After s. c. administration, the CS-bPEI-INS NPs greatly improved the INS bioavailability. As a result, the CS-bPEI-INS NPs produced sustained glucose-lowering effects, promising short-term and long-term hypoglycemic efficacy in the T2DM model. Furthermore, the treatment of the CS-bPEI-INS NPs greatly protected the islet in the pancreas and prevented the associated complications of the T2DM, such as cardiac fibrosis in the myocardial interstitium and the perivascular area. In a word, the CS-bPEI-INS NPs was an encouraging long-acting formulation of insulin and had great potential in the treatment of T2DM.


Asunto(s)
Quitosano , Diabetes Mellitus Tipo 2 , Nanopartículas , Humanos , Insulina , Polietileneimina , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Portadores de Fármacos
15.
Bioorg Med Chem Lett ; 22(18): 5853-6, 2012 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-22884990

RESUMEN

Inspired by the potent DNA-cleaving activity of the Cu(II) complex of monopyrrole-polyamide dimer 1 (i.e., 1@Cu(2+)), we designed a new dimeric dipyrrole-polyamide analog 2 with the aim to optimize the catalytic activities of the metal complexes of this type of polypyrrole-polyamides. Compound 2 was prepared in 50% yield from the reaction of 1-methyl-4-[(1-methyl-4-nitro-1H-pyrrole-2-carbonyl)-amino]-1H-pyrrole-2-carboxylic acid with 2,2'-(ethane-1,2-diylbis(oxy))diethanamine, and fully characterized on the basis of NMR ((1)H and (13)C), MS (ESI and HR) and IR. Spectrophotometric titration, ESI-MS and conductivity measurements indicated that compound 2 formed a 1:1 complex with Cu(2+) ion (i.e., 2@Cu(2+)). Agarose gel electrophoresis studies indicated that 2@Cu(2+) was capable of efficiently converting pBR322 DNA into open circular and linear forms under physiological conditions, most probably via an oxidative mechanism. Its overall catalytic activity was estimated to be at least 30-fold higher than that of 1@Cu(2+). The fact that the cleaving activities of these Cu(II) complexes parallel, exactly, their binding affinities, raises the possibility that the cleaving activities of polypyrrole-polyamide derivatives of the type can be regulated by the binding affinities.


Asunto(s)
Cobre/química , División del ADN/efectos de los fármacos , ADN Bacteriano/química , Nylons/química , Compuestos Organometálicos/síntesis química , Compuestos Organometálicos/farmacología , Pirroles/química , ADN Bacteriano/metabolismo , Dimerización , Estructura Molecular , Compuestos Organometálicos/química , Plásmidos/química , Plásmidos/metabolismo , Relación Estructura-Actividad
16.
Chem Biodivers ; 9(6): 1125-32, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22700230

RESUMEN

A simple polyether-tethered pyrrole-polyamide dimer 1 was synthesized in 50% yield from the reaction of 2,2,2-trichloro-1-(1-methyl-4-nitro-1H-pyrrol-2-yl)ethanone with 2,2'-[1,2-ethanediylbis(oxy)]bisethanamine, and fully characterized on the basis of ¹H- and ¹³C-NMR, MS, HR-MS, and IR data. Agarose gel-electrophoresis study of the cleavage of plasmid pBR322 DNA by the complexes of compound 1 with seven metal ions indicated that most of the metal complexes were capable of efficiently cleaving DNA at pH 7.0 and 37°. Among them, the Cu(II) complex exhibited the highest activity, with the maximal catalytic rate constant k(max) and Michaelis constant K(M) being 5.61 h⁻¹ and 7.30 mM, respectively. Spectroscopic, ESI-MS, ethidium-bromide (EB) displacement, and viscosity experiments indicated that compound 1 could form a 1 : 1 complex with Cu(II) ion, and that this complex showed moderate binding affinity toward calf-thymus DNA.


Asunto(s)
Complejos de Coordinación/química , ADN/metabolismo , Nylons/química , Poliésteres/química , Pirroles/química , Animales , Bovinos , Cobre/química , División del ADN , Dimerización , Concentración de Iones de Hidrógeno , Plásmidos/metabolismo
17.
Chem Soc Rev ; 40(11): 5588-617, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21863197

RESUMEN

Lignocellulosic biomass is the most abundant and bio-renewable resource with great potential for sustainable production of chemicals and fuels. This critical review provides insights into the state-of the-art accomplishments in the chemocatalytic technologies to generate fuels and value-added chemicals from lignocellulosic biomass, with an emphasis on its major component, cellulose. Catalytic hydrolysis, solvolysis, liquefaction, pyrolysis, gasification, hydrogenolysis and hydrogenation are the major processes presently studied. Regarding catalytic hydrolysis, the acid catalysts cover inorganic or organic acids and various solid acids such as sulfonated carbon, zeolites, heteropolyacids and oxides. Liquefaction and fast pyrolysis of cellulose are primarily conducted over catalysts with proper acidity/basicity. Gasification is typically conducted over supported noble metal catalysts. Reaction conditions, solvents and catalysts are the prime factors that affect the yield and composition of the target products. Most of processes yield a complex mixture, leading to problematic upgrading and separation. An emerging technique is to integrate hydrolysis, liquefaction or pyrolysis with hydrogenation over multifunctional solid catalysts to convert lignocellulosic biomass to value-added fine chemicals and bio-hydrocarbon fuels. And the promising catalysts might be supported transition metal catalysts and zeolite-related materials. There still exist technological barriers that need to be overcome (229 references).


Asunto(s)
Biocombustibles , Biomasa , Celulosa/química , Catálisis , Hidrogenación , Hidrólisis , Solventes/química
18.
J Hazard Mater ; 431: 128547, 2022 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-35220117

RESUMEN

Microplastics (MPs), nanoplastics (NPs) and antibiotic resistance genes (ARGs), as emerging pollutants, have been frequently detected in wastewater treatment plants. However, the behavior of phosphorus and ARGs under MP and NP (MP/NP) pressure in biological phosphorus removal (BPR) system is still unknown. This study investigated the effects of MP/NPs on phosphorus removal and ARGs propagation in BPR system. Results showed that MP/NPs had no influence on phosphorus removal, but significantly promoted the amplification of tetracycline resistance genes (TRGs). Moreover, the TRG abundance were more facilitated by MPs than NPs, and the TRGs of efflux pump and enzymatic modification mechanism were mainly enriched. Meanwhile, MP/NPs increased the transmission risk of multiple resistance genes and mobile gene elements (MGEs). Microbial communities demonstrated the main polyphosphate accumulating organisms shifted from Acinetobacter to unclassified_Gammaproteobacteria, which explained why phosphorus removal efficiency was unaffected with MP/NP addition. Correlation analysis revealed there was no significant correlation between ARGs and MGEs (intI1 and intI2), but the abundances of potential hosts of ARGs were significantly increased with MP/NP addition, implying microbial community structure changes rather than gene horizontal transfer was the main factor promoting ARG propagation under MP/NP pressure.


Asunto(s)
Antibacterianos , Microplásticos , Antibacterianos/farmacología , Farmacorresistencia Microbiana/genética , Genes Bacterianos , Fósforo , Plásticos
19.
J Hazard Mater ; 432: 128715, 2022 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-35305418

RESUMEN

Microplastics (MPs) and nanoplastics (NPs), as emerging pollutants, are frequently detected in wastewater treatment plants. However, studies comparing the effects of MPs versus NPs on nitrogen removal by activated sludge are rarely reported. Here, the responses of nitrogen removal performance, microbial community and functional genes to MPs and NPs in sequencing batch reactors were investigated. Results revealed that MPs (10 and 1000 µg/L) had no effects on nitrogen removal. While upon exposure to NPs, although low concentration (10 µg/L) of NPs showed no remarkable influence on nitrogen removal, high level (1000 µg/L) of NPs decreased NH4+-N removal efficiency by 24.48% and caused accumulation of NO3--N and NO2--N. These inhibitory probably due to the acute toxicity of NPs to activated sludge, which was reflected by the increasing reactive oxygen species generation and lactate dehydrogenase release. The toxic effects of NPs further declined the relative abundance of nitrifiers (e.g., Nitrospira) and denitrifiers (e.g., Dechloromonas). These negative effects, accompanied by a decrease in abundance of amoA and nxrA genes related to nitrification (30.01% and 65.24% of control) and narG, nirK and nirS genes associated with denitrification (78.59%, 61.39%, and 86.17% of control), directly illustrated the attenuate phenomenon observed in nitrogen removal.


Asunto(s)
Microbiota , Microplásticos , Reactores Biológicos , Desnitrificación , Microbiota/genética , Microplásticos/toxicidad , Nitrificación , Nitrógeno/análisis , Plásticos , Aguas del Alcantarillado
20.
Arch Oral Biol ; 129: 105199, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34174589

RESUMEN

OBJECTIVE: The mechanism underlying lipopolysaccharide (LPS)-induced primary human periodontal ligament (PDLC) cell injury is unclear. In this study, we focused on the therapeutic function of asperuloside (ASP) on LPS-induced cell injury. DESIGN: The study enrolled 41 participants, including 18 healthy controls and 23 CP patients. Western blotting was used to measure the expression of Toll-like receptor 4 (TLR4), phosphorylated p65 (p-p65) and cyclin D1. Enzyme-linked immunosorbent assays (ELISAs) were utilized to evaluate the protein levels of proinflammatory factors interleukin (IL)-1ß, IL-6, IL-8 and tumor necrosis factor alpha (TNF-α). MTT assays and 5-ethynyl-2'-deoxyuridine (EdU) staining were performed to investigate cell proliferation. Immunohistochemistry was used to detect TLR4 and p65 expression in gingival tissues. RESULTS AND CONCLUSIONS: Asperuloside ameliorates lipopolysaccharide-induced PDLC cell injury by decreasing TLR4 expression and NF-κB activation, while this protective effect of ASP was reversed by TLR4 overexpression.


Asunto(s)
Lipopolisacáridos , Receptor Toll-Like 4 , Monoterpenos Ciclopentánicos , Glucósidos , Humanos , FN-kappa B , Ligamento Periodontal , Piranos , Factor de Necrosis Tumoral alfa
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