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1.
J Environ Manage ; 368: 122199, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39146646

RESUMEN

Coastal wetland ecosystems harbor rich biodiversity and possess significant ecosystem service value (ESV). Therefore, it offers a range of crucial ecosystem services (ES) for human well-being and socio-economic development. Taking the Hainan Island coastal zone (HICZ) as a case study, the spatio-temporal characteristics of land use and land cover change (LULCC), and its associated ESV in wetland landscapes were analyzed over three time points (2000, 2010 and 2020). We explored the spatio-temporal evolution trajectory of ESV on the basis of geo-information tupu. Then, future land use simulation (FLUS) was employed to predict wetland patterns and ESV under three different scenarios: business as usual (BAU), ecological conservation first (ECF), and economic development first (EDF). The results showed that over the past two decades, a significant proportion (exceeding 80%) of the overall wetland region was comprised of offshore and coastal wetlands (OCW) as well as constructed wetlands (CW); these formed the matrix of the landscape. The area of building land (BL) continued to exhibit a consistent upward trend. Expanding by 2.18 times, it represented the most significant increase in the rate of dynamic changes in BL. The main ES in the HICZ corresponded to the regulation services (53.57%) and the support services (27.58%). The ESV of wetland losses accounted for 45.17% (43.08 × 108 yuan) of the total loss. The spatial differentiation of ESV in the HICZ was larger in the southwest and the northeast regions, while it was comparatively lower in the north. The transformation in the area of early and late change types accounted for 236.46 km2 and 356.69 km2, respectively. The scenario ECF was achieved with an optimal development of ESV (1807.72 × 108 yuan), which was coordinated with the high-level of development of regional ES functions and the economy. These findings provide valuable information for the sustainable development as well as the protection of ecology and environment of the coastal zone under the background of the construction of Hainan pilot free trade zone in the future.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Humedales , China , Biodiversidad , Islas , Análisis Espacio-Temporal
2.
Environ Sci Ecotechnol ; 8: 100123, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36156989

RESUMEN

In this study, metal-organic framework MIL-53(Al) was synthesized and studied to understand the different mechanisms between normal MIL-53(Al) and 2D metal-organic framework MIL-53(Al) for removing fluoride. Comparatively, the 2D MIL-53(Al) had two-dimensional linear morphology rather than block shape, indicating more expose adsorptive sites than normal MIL-53(Al). The batch adsorption experiments were applied to investigate the performance of 2D MIL-53(Al), including pH, adsorption kinetics, and thermodynamics. The 2D MIL-53(Al) (75.50 mg/g) showed better adsorption capacity than normal MIL-53(Al) (35.63 mg/g). The adsorption process of 2D MIL-53(Al) followed the pseudo-first-order model and Langmuir model. The adsorption mechanism of this material was further studied by using experimental characterization and density functional theory calculations in detail. The main adsorptive sites were Al and O in the 2D MIL-53(Al), and the relationship between fluoride binding with Al and O was HF2 - > HF > F-. The species of fluoride were HF2 -, HF, F at different pH and concentrations. Hence, this study provides a significant way on the application of two-dimensional materials for removing fluoride.

3.
Nat Commun ; 2: 599, 2011 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-22186895

RESUMEN

Human IgG3 displays the strongest effector functions of all IgG subclasses but has a short half-life for unresolved reasons. Here we show that IgG3 binds to IgG-salvage receptor (FcRn), but that FcRn-mediated transport and rescue of IgG3 is inhibited in the presence of IgG1 due to intracellular competition between IgG1 and IgG3. We reveal that this occurs because of a single amino acid difference at position 435, where IgG3 has an arginine instead of the histidine found in all other IgG subclasses. While the presence of R435 in IgG increases binding to FcRn at neutral pH, it decreases binding at acidic pH, affecting the rescue efficiency-but only in the presence of H435-IgG. Importantly, we show that in humans the half-life of the H435-containing IgG3 allotype is comparable to IgG1. H435-IgG3 also gave enhanced protection against a pneumococcal challenge in mice, demonstrating H435-IgG3 to be a candidate for monoclonal antibody therapies.


Asunto(s)
Agammaglobulinemia/inmunología , Anticuerpos Monoclonales/inmunología , Antígenos de Histocompatibilidad Clase I/metabolismo , Inmunoglobulina G/inmunología , Terapia Molecular Dirigida/métodos , Infecciones Neumocócicas/tratamiento farmacológico , Transporte de Proteínas/inmunología , Receptores Fc/metabolismo , Agammaglobulinemia/tratamiento farmacológico , Agammaglobulinemia/metabolismo , Agammaglobulinemia/patología , Sustitución de Aminoácidos , Animales , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/metabolismo , Anticuerpos Monoclonales/uso terapéutico , Arginina/genética , Arginina/inmunología , Arginina/metabolismo , Unión Competitiva , Línea Celular Tumoral , Modelos Animales de Enfermedad , Semivida , Histidina/genética , Histidina/inmunología , Histidina/metabolismo , Antígenos de Histocompatibilidad Clase I/inmunología , Humanos , Concentración de Iones de Hidrógeno , Inmunoglobulina G/administración & dosificación , Inmunoglobulina G/metabolismo , Inmunoglobulina G/uso terapéutico , Ratones , Infecciones Neumocócicas/inmunología , Infecciones Neumocócicas/metabolismo , Unión Proteica , Receptores Fc/inmunología , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/inmunología
4.
J Mol Endocrinol ; 38(1-2): 113-25, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17242174

RESUMEN

The IGF-binding protein (IGFBP) family consists of six proteins that are expressed and secreted in different tissues. The proteins are regulators of physiological processes throughout the body by modulating the activity of IGF-I and IGF-II. In this article, we describe the coordinated expression of IGFBP5 and MN1 in meningiomas. MN1 is a transcriptional co-activator and we show that MN1 stimulates the IGFBP5 promoter in Hep3B cells. A CACCC-containing sequence, located 140 bp upstream of the transcription start site of the promoter, is required for MN1 action. This sequence matches with the CACCCAC consensus sequence that was selected in an oligonucleotide selection assay performed for MN1. The CACCC element has also been shown to be important for induction of the IGFBP5 promoter by retinoic acid (RA) and progesterone (Pg). We were unable to confirm the effect of Pg on the promoter in Hep3B and U2-osteosarcoma cells regardless of the presence of MN1. On the other hand, we show that induction of the promoter by RA depends on co-expressed MN1 in Hep3B cells. MN1TEL, a leukemia-related fusion protein containing parts of the MN1 and TEL (ETV6) genes, is capable of stimulating the IGFBP5 promoter but is unable to cooperate with RA in Hep3B cells. This suggests that the effects of RA can be negatively affected in leukemias caused by MN1TEL.


Asunto(s)
Secuencia de Consenso/genética , Proteína 5 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Regiones Promotoras Genéticas/fisiología , Proteínas Supresoras de Tumor/fisiología , Regulación hacia Arriba/fisiología , Células 3T3 , Animales , Secuencia de Bases , Línea Celular Tumoral , Células HeLa , Humanos , Proteína 5 de Unión a Factor de Crecimiento Similar a la Insulina/biosíntesis , Meningioma/genética , Meningioma/metabolismo , Ratones , Datos de Secuencia Molecular , Transactivadores
5.
Vaccine ; 23(43): 5082-90, 2005 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-16029915

RESUMEN

This article describes a method in which multiple vaccine candidates can be tested in parallel for their immunogenicity. Antigens derived from the genome sequence of Neisseria meningitidis group B strain MC58 were cloned and expressed as recombinant proteins fused to the IgG-binding domain ZZ or to a His-tag. Immunization of mice with a mixture of 22 ZZ-fusion antigens applied with the adjuvant QuilA, induced an enhanced immune response as compared to the same antigen mixture without QuilA or a mixture containing the corresponding His-tagged antigens with QuilA. The enhanced immune response of the ZZ-fusion antigens/QuilA preparation was apparent from 1) the higher number of antigens in the mixture that elicited an antibody response and 2) the much lower antigen dose needed to get this response. Our approach using ZZ-fusion antigens/QuilA mixtures may serve as a high throughput discovery tool for new vaccine candidates.


Asunto(s)
Antígenos/administración & dosificación , Inmunoglobulina G/química , Inmunoglobulinas/metabolismo , Vacunas Sintéticas/administración & dosificación , Adyuvantes Inmunológicos , Animales , Presentación de Antígeno , Antígenos/metabolismo , Proteínas Portadoras/administración & dosificación , Proteínas Portadoras/inmunología , Epítopos , Hibridomas , Inmunización , Ratones , Proteínas Recombinantes de Fusión/administración & dosificación , Proteínas Recombinantes de Fusión/inmunología , Vacunas Sintéticas/inmunología
6.
Infect Immun ; 70(9): 5319-21, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12183592

RESUMEN

Screening of 7,680 Salmonella enterica serovar Enteritidis mutants for attenuation in a chicken macrophage infection model yielded a series of mutants including several with defects in previously unrecognized Salmonella virulence genes. One of the newly identified genes was the pbpA2 gene, belonging to the penicillin binding protein gene family.


Asunto(s)
Proteínas Bacterianas , Genes Bacterianos , Hexosiltransferasas , Macrófagos/microbiología , Peptidil Transferasas , Salmonella enterica/genética , Salmonella enterica/patogenicidad , Animales , Proteínas Portadoras/genética , Pollos , Técnicas In Vitro , Familia de Multigenes , Muramoilpentapéptido Carboxipeptidasa/genética , Mutación , Proteínas de Unión a las Penicilinas , Virulencia/genética
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