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1.
Immunity ; 55(3): 405-422.e11, 2022 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-35180378

RESUMEN

Developmental origins of dendritic cells (DCs) including conventional DCs (cDCs, comprising cDC1 and cDC2 subsets) and plasmacytoid DCs (pDCs) remain unclear. We studied DC development in unmanipulated adult mice using inducible lineage tracing combined with clonal DNA "barcoding" and single-cell transcriptome and phenotype analysis (CITE-seq). Inducible tracing of Cx3cr1+ hematopoietic progenitors in the bone marrow showed that they simultaneously produce all DC subsets including pDCs, cDC1s, and cDC2s. Clonal tracing of hematopoietic stem cells (HSCs) and of Cx3cr1+ progenitors revealed clone sharing between cDC1s and pDCs, but not between the two cDC subsets or between pDCs and B cells. Accordingly, CITE-seq analyses of differentiating HSCs and Cx3cr1+ progenitors identified progressive stages of pDC development including Cx3cr1+ Ly-6D+ pro-pDCs that were distinct from lymphoid progenitors. These results reveal the shared origin of pDCs and cDCs and suggest a revised scheme of DC development whereby pDCs share clonal relationship with cDC1s.


Asunto(s)
Linfocitos B , Células Dendríticas , Animales , Recuento de Células , Corea , Células Madre Hematopoyéticas , Ratones
2.
Proc Natl Acad Sci U S A ; 121(4): e2317929121, 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38227649

RESUMEN

The hierarchical model of hematopoiesis posits that self-renewing, multipotent hematopoietic stem cells (HSCs) give rise to all blood cell lineages. While this model accounts for hematopoiesis in transplant settings, its applicability to steady-state hematopoiesis remains to be clarified. Here, we used inducible clonal DNA barcoding of endogenous adult HSCs to trace their contribution to major hematopoietic cell lineages in unmanipulated animals. While the majority of barcodes were unique to a single lineage, we also observed frequent barcode sharing between multiple lineages, specifically between lymphocytes and myeloid cells. These results suggest that both single-lineage and multilineage contributions by HSCs collectively drive continuous hematopoiesis, and highlight a close relationship of myeloid and lymphoid development.


Asunto(s)
Células Madre Adultas , Células Madre Hematopoyéticas , Animales , Diferenciación Celular , Hematopoyesis/genética , Linaje de la Célula/genética
3.
Proc Natl Acad Sci U S A ; 120(22): e2302019120, 2023 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-37216517

RESUMEN

Mammalian aging is associated with multiple defects of hematopoiesis, most prominently with the impaired development of T and B lymphocytes. This defect is thought to originate in hematopoietic stem cells (HSCs) of the bone marrow, specifically due to the age-dependent accumulation of HSCs with preferential megakaryocytic and/or myeloid potential ("myeloid bias"). Here, we tested this notion using inducible genetic labeling and tracing of HSCs in unmanipulated animals. We found that the endogenous HSC population in old mice shows reduced differentiation into all lineages including lymphoid, myeloid, and megakaryocytic. Single-cell RNA sequencing and immunophenotyping (CITE-Seq) showed that HSC progeny in old animals comprised balanced lineage spectrum including lymphoid progenitors. Lineage tracing using the aging-induced HSC marker Aldh1a1 confirmed the low contribution of old HSCs across all lineages. Competitive transplantations of total bone marrow cells with genetically marked HSCs revealed that the contribution of old HSCs was reduced, but compensated by other donor cells in myeloid cells but not in lymphocytes. Thus, the HSC population in old animals becomes globally decoupled from hematopoiesis, which cannot be compensated in lymphoid lineages. We propose that this partially compensated decoupling, rather than myeloid bias, is the primary cause of the selective impairment of lymphopoiesis in older mice.


Asunto(s)
Envejecimiento , Células Madre Hematopoyéticas , Ratones , Animales , Linaje de la Célula , Diferenciación Celular , Médula Ósea , Hematopoyesis , Mamíferos
4.
Blood ; 142(5): 460-476, 2023 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-37267505

RESUMEN

The chromosome 9p21 locus comprises several tumor suppressor genes including MTAP, CDKN2A, and CDKN2B, and its homo- or heterozygous deletion is associated with reduced survival in multiple cancer types. We report that mice with germ line monoallelic deletion or induced biallelic deletion of the 9p21-syntenic locus (9p21s) developed a fatal myelodysplastic syndrome/myeloproliferative neoplasm (MDS/MPN)-like disease associated with aberrant trabecular bone formation and/or fibrosis in the bone marrow (BM). Reciprocal BM transfers and conditional targeting of 9p21s suggested that the disease originates in the BM stroma. Single-cell analysis of 9p21s-deficient BM stroma revealed the expansion of chondrocyte and osteogenic precursors, reflected in increased osteogenic differentiation in vitro. It also showed reduced expression of factors maintaining hematopoietic stem/progenitor cells, including Cxcl12. Accordingly, 9p21s-deficient mice showed reduced levels of circulating Cxcl12 and concomitant upregulation of the profibrotic chemokine Cxcl13 and the osteogenesis- and fibrosis-related multifunctional glycoprotein osteopontin/Spp1. Our study highlights the potential of mutations in the BM microenvironment to drive MDS/MPN-like disease.


Asunto(s)
Médula Ósea , Osteogénesis , Ratones , Animales , Médula Ósea/patología , Células Madre Hematopoyéticas/metabolismo , Genes Supresores de Tumor , Diferenciación Celular
5.
Immunity ; 45(3): 597-609, 2016 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-27590115

RESUMEN

Hematopoietic stem cells (HSCs) sustain long-term reconstitution of hematopoiesis in transplantation recipients, yet their role in the endogenous steady-state hematopoiesis remains unclear. In particular, recent studies suggested that HSCs provide a relatively minor contribution to immune cell development in adults. We directed transgene expression in a fraction of HSCs that maintained reconstituting activity during serial transplantations. Inducible genetic labeling showed that transgene-expressing HSCs gave rise to other phenotypic HSCs, confirming their top position in the differentiation hierarchy. The labeled HSCs rapidly contributed to committed progenitors of all lineages and to mature myeloid cells and lymphocytes, but not to B-1a cells or tissue macrophages. Importantly, labeled HSCs gave rise to more than two-thirds of all myeloid cells and platelets in adult mice, and this contribution could be accelerated by an induced interferon response. Thus, classically defined HSCs maintain immune cell development in the steady state and during systemic cytokine responses.


Asunto(s)
Linaje de la Célula/fisiología , Hematopoyesis/fisiología , Células Madre Hematopoyéticas/fisiología , Animales , Linfocitos B/metabolismo , Linfocitos B/fisiología , Plaquetas/metabolismo , Plaquetas/fisiología , Diferenciación Celular/fisiología , Trasplante de Células Madre Hematopoyéticas/métodos , Células Madre Hematopoyéticas/metabolismo , Interferones/metabolismo , Macrófagos/metabolismo , Macrófagos/fisiología , Ratones , Ratones Endogámicos C57BL , Células Mieloides/metabolismo , Células Mieloides/fisiología
6.
J Biol Chem ; 296: 100024, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33410399

RESUMEN

The human genome contains vast genetic diversity as naturally occurring coding variants, yet the impact of these variants on protein function and physiology is poorly understood. RGS14 is a multifunctional signaling protein that suppresses synaptic plasticity in dendritic spines of hippocampal neurons. RGS14 also is a nucleocytoplasmic shuttling protein, suggesting that balanced nuclear import/export and dendritic spine localization are essential for RGS14 functions. We identified genetic variants L505R (LR) and R507Q (RQ) located within the nuclear export sequence (NES) of human RGS14. Here we report that RGS14 encoding LR or RQ profoundly impacts protein functions in hippocampal neurons. RGS14 membrane localization is regulated by binding Gαi-GDP, whereas RGS14 nuclear export is regulated by Exportin 1 (XPO1). Remarkably, LR and RQ variants disrupt RGS14 binding to Gαi1-GDP and XPO1, nucleocytoplasmic equilibrium, and capacity to inhibit long-term potentiation (LTP). Variant LR accumulates irreversibly in the nucleus, preventing RGS14 binding to Gαi1, localization to dendritic spines, and inhibitory actions on LTP induction, while variant RQ exhibits a mixed phenotype. When introduced into mice by CRISPR/Cas9, RGS14-LR protein expression was detected predominantly in the nuclei of neurons within hippocampus, central amygdala, piriform cortex, and striatum, brain regions associated with learning and synaptic plasticity. Whereas mice completely lacking RGS14 exhibit enhanced spatial learning, mice carrying variant LR exhibit normal spatial learning, suggesting that RGS14 may have distinct functions in the nucleus independent from those in dendrites and spines. These findings show that naturally occurring genetic variants can profoundly alter normal protein function, impacting physiology in unexpected ways.


Asunto(s)
Núcleo Celular/metabolismo , Hipocampo/metabolismo , Potenciación a Largo Plazo , Mutación , Neuronas/metabolismo , Proteínas RGS/genética , Animales , Hipocampo/citología , Hipocampo/fisiología , Humanos , Carioferinas/metabolismo , Ratones , Plasticidad Neuronal , Transporte de Proteínas , Proteínas RGS/metabolismo , Receptores Citoplasmáticos y Nucleares/metabolismo , Transducción de Señal , Aprendizaje Espacial , Proteína Exportina 1
7.
Ann Vasc Surg ; 46: 331-336, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28743653

RESUMEN

BACKGROUND: To analyze the outcomes of arteriovenous fistulae (AVFs) creation in octogenarians. METHODS: A retrospective study of 47 AVFs created in patients aged 80 years and above from 2008 to 2014. Patient and AVF characteristics and outcomes were evaluated. Predictors of patency were analyzed with multivariate analysis and Kaplan-Meier patency, and survival analysis was performed. RESULTS: Forty-seven of 1,259 AVFs created were for octogenarians (4%). Mean age was 83 years old (range: 80-91 years), with 27 male (57%) and 35 with tunneled dialysis catheters in situ (75%). There were a total of 15 (32%) radiocephalic AVFs, 30 (64%) brachial-cephalic AVFs, and 2 (4%) brachial-basilic transposition AVFs. At 12 months, assisted primary patency rate was 28% (13 patients) while primary failure rate was 72% (34 patients). Subset analysis showed brachial-cephalic AVFs to have the highest assisted primary patency rate at 33%. Within 24 months, tunneled dialysis catheter-related sepsis rate was 31% (11 patients). Multivariate analysis did not reveal any factor to be statistically significant in predicting AVF patency. Kaplan-Meier survival curve showed a 50% survival rate at 63 months after AVF creation. CONCLUSIONS: In view of high AVF primary failure rate and relatively low tunneled dialysis catheter bacteremia rate, long-term tunneled dialysis catheters as the main form of hemodialysis renal access may be a viable option. However, with 50% of end-stage renal failure patients surviving up to 63 months after AVF creation, the risks and benefits of long-term tunneled dialysis catheters must be balanced against those of AVF creation.


Asunto(s)
Derivación Arteriovenosa Quirúrgica , Fallo Renal Crónico/terapia , Diálisis Renal , Extremidad Superior/irrigación sanguínea , Factores de Edad , Anciano de 80 o más Años , Derivación Arteriovenosa Quirúrgica/efectos adversos , Derivación Arteriovenosa Quirúrgica/mortalidad , Cateterismo Venoso Central , Distribución de Chi-Cuadrado , Toma de Decisiones Clínicas , Femenino , Humanos , Estimación de Kaplan-Meier , Fallo Renal Crónico/diagnóstico , Fallo Renal Crónico/mortalidad , Longevidad , Masculino , Análisis Multivariante , Diálisis Renal/efectos adversos , Diálisis Renal/mortalidad , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento , Grado de Desobstrucción Vascular
8.
Eur J Clin Pharmacol ; 73(10): 1199-1208, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28681177

RESUMEN

AIM: The aim of this study was to identify the best probiotic supplementation in triple therapy for pediatric population with Helicobacter pylori infection. METHODS: Eligible trials were identified by comprehensive searches. Relative risks with 95% confidence intervals and relative ranks with P scores were assessed. RESULTS: Twenty-nine trials (3122 participants) involving 17 probiotic regimens were identified. Compared with placebo, probiotic-supplemented triple therapy significantly increased H. pylori eradication rates (relative ratio (RR) 1.19, 95% CI 1.13-1.25) and reduced the incidence of total side effects (RR 0.49, 95% CI 0.38-0.65). Furthermore, to supplemented triple therapy, Lactobacillus casei was identified the best for H. pylori eradication rates (P score = 0.84), and multi-strain of Lactobacillus acidophilus and Lactobacillus rhamnosus for total side effects (P score = 0.93). As for the subtypes of side effects, multi-strain of Bifidobacterium infantis, Bifidobacterium longum, L. acidophilus, L. casei, Lactobacillus plantarum, Lactobacillus reuteri, L. rhamnosus, Lactobacillus salivarius, Lactobacillus sporogenes, and Streptococcus thermophilus was the best to reduce the incidence of diarrhea; multi-strain of Bacillus mesentericus, Clostridium butyricum, and Streptococcus faecalis for loss of appetite; multi-strain of B. longum, Lactobacillus bulgaricus, and S. thermophilus for constipation; multi-strain of Bifidobacterium bifidum, B. infantis, L. acidophilus, L. bulgaricus, L. casei, L. reuteri, and Streptococcus for taste disturbance; Saccharomyces boulardii for bloating; and multi-strain of Bifidobacterium breve, B. infantis, L. acidophilus, L. bulgaricus, L. casei, L. rhamnosus, and S. thermophilus for nausea/vomiting. CONCLUSIONS: Probiotics are recommended to supplement triple therapy in pediatrics, and the effectiveness of triple therapy is associated with specific probiotic supplementation.


Asunto(s)
Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori/efectos de los fármacos , Probióticos/administración & dosificación , Probióticos/uso terapéutico , Niño , Suplementos Dietéticos , Quimioterapia Combinada , Infecciones por Helicobacter/microbiología , Humanos , Metaanálisis en Red , Probióticos/efectos adversos , Resultado del Tratamiento
9.
Nucleic Acids Res ; 42(15): 9771-80, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25100870

RESUMEN

NONO, SFPQ and PSPC1 make up a family of proteins with diverse roles in transcription, RNA processing and DNA double-strand break (DSB) repair. To understand long-term effects of loss of NONO, we characterized murine embryonic fibroblasts (MEFs) from knockout mice. In the absence of genotoxic stress, wild-type and mutant MEFs showed similar growth rates and cell cycle distributions, and the mutants were only mildly radiosensitive. Further investigation showed that NONO deficiency led to upregulation of PSPC1, which replaced NONO in a stable complex with SFPQ. Knockdown of PSPC1 in a NONO-deficient background led to severe radiosensitivity and delayed resolution of DSB repair foci. The DNA-dependent protein kinase (DNA-PK) inhibitor, NU7741, sensitized wild-type and singly deficient MEFs, but had no additional effect on doubly deficient cells, suggesting that NONO/PSPC1 and DNA-PK function in the same pathway. We tested whether NONO and PSPC1 might also affect repair indirectly by influencing mRNA levels for other DSB repair genes. Of 12 genes tested, none were downregulated, and several were upregulated. Thus, NONO or related proteins are critical for DSB repair, NONO and PSPC1 are functional homologs with partially interchangeable functions and a compensatory response involving PSPC1 blunts the effect of NONO deficiency.


Asunto(s)
Reparación del ADN , Proteínas de Unión al ADN/genética , Proteínas Nucleares/metabolismo , Proteínas de Unión al ARN/metabolismo , Animales , Proliferación Celular , Células Cultivadas , Roturas del ADN de Doble Cadena , Embrión de Mamíferos/citología , Fibroblastos/metabolismo , Ratones , Ratones Noqueados , Tolerancia a Radiación , Regulación hacia Arriba
10.
J Surg Oncol ; 109(7): 730-9, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24374987

RESUMEN

BACKGROUND: Advanced colorectal cancer (CRC) is prone to developing peritoneal carcinomatosis (PC). This case-control study was to compare the efficacy and safety of cytoreductive surgery (CRS) versus CRS plus hyperthermic intraperitoneal chemotherapy (HIPEC) in Chinese patients with CRC PC. METHODS: The 62 consecutive PC patients were treated with CRS (Control group, n = 29) or CRS + HIPEC (Study group, n = 33). The primary end point was overall survival (OS), the secondary end points were perioperative safety profiles. RESULTS: For the comparison of Control versus Study groups, the peritoneal cancer index (PCI) ≤20 was 13 (44.8%) versus 16 (48.5%) patients (P = 0.78), complete cytoreduction (CC0-1) was achieved in 9 (31.0%) versus 14 (42.4%) cases (P = 0.36). At the median OS was 8.5 (95% confidence interval [CI] 4.7-12.4) versus 13.7 (95% CI 10.0-16.5) months (P = 0.02), the 1-, 2-, and 3-year survival rates were 27.5% versus 63.6%, 12.0% versus 20.0%, and 0.0% versus 16.0%, respectively. Serious adverse events in postoperative 30 days were 9.4% versus 28.6% (P = 0.11). Multivariate analysis revealed that CRS + HIPEC, CC0-1, adjuvant chemotherapy ≥6 cycles were independent factors for OS benefit. CONCLUSION: CRS + HIPEC could improve OS for CRC PC patients, with acceptable perioperative safety.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Neoplasias Colorrectales/patología , Hipertermia Inducida , Neoplasias Peritoneales/terapia , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Terapia Combinada , Femenino , Humanos , Infusiones Parenterales , Masculino , Persona de Mediana Edad , Neoplasias Peritoneales/mortalidad
11.
Heliyon ; 10(6): e27841, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38533064

RESUMEN

Green technology transformation is crucial for China to achieve its carbon peak and carbon neutrality goals. We use green transformation keywords extracted from the annual reports of listed firms to construct a green technology transformation intensity index for enterprises and investigate the impact of green technology transformation on corporate financial constraints. Our findings indicate that green technology transformation significantly mitigates corporate financial constraints, with green subsidies and debt financing as crucial mechanisms. Moreover, this effect is particularly pronounced in high-carbon-intensity industries, firms with fewer political connections, and firms affected by the carbon trading pilot. Additionally, digital and green transformations have a synergistic effect on alleviating corporate financial constraints. Therefore, we should promote the green technology transformation of enterprises and guide green finance to serve the real economy, effectively solve the financing dilemma of green enterprises, and provide strong green kinetic energy for sustainable development.

12.
Nature ; 448(7149): 78-82, 2007 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-17611541

RESUMEN

Cell signalling requires efficient Ca2+ mobilization from intracellular stores through Ca2+ release channels, as well as predicted counter-movement of ions across the sarcoplasmic/endoplasmic reticulum membrane to balance the transient negative potential generated by Ca2+ release. Ca2+ release channels were cloned more than 15 years ago, whereas the molecular identity of putative counter-ion channels remains unknown. Here we report two TRIC (trimeric intracellular cation) channel subtypes that are differentially expressed on intracellular stores in animal cell types. TRIC subtypes contain three proposed transmembrane segments, and form homo-trimers with a bullet-like structure. Electrophysiological measurements with purified TRIC preparations identify a monovalent cation-selective channel. In TRIC-knockout mice suffering embryonic cardiac failure, mutant cardiac myocytes show severe dysfunction in intracellular Ca2+ handling. The TRIC-deficient skeletal muscle sarcoplasmic reticulum shows reduced K+ permeability, as well as altered Ca2+ 'spark' signalling and voltage-induced Ca2+ release. Therefore, TRIC channels are likely to act as counter-ion channels that function in synchronization with Ca2+ release from intracellular stores.


Asunto(s)
Calcio/metabolismo , Membranas Intracelulares/metabolismo , Canales Iónicos/metabolismo , Músculo Esquelético/metabolismo , Miocitos Cardíacos/metabolismo , Animales , Señalización del Calcio , Citoplasma/metabolismo , Corazón/embriología , Canales Iónicos/aislamiento & purificación , Ratones , Ratones Noqueados , Microsomas/metabolismo , Datos de Secuencia Molecular , Permeabilidad , Potasio/metabolismo , Conejos , Retículo Sarcoplasmático/metabolismo
13.
RSC Adv ; 13(10): 6688-6698, 2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36860530

RESUMEN

In most of the research about graphitic carbon nitride (g-C3N4), g-C3N4 is prepared through the calcination of nitrogen-rich precursors. However, such a preparation method is time-consuming, and the photocatalytic performance of pristine g-C3N4 is lackluster due to the unreacted amino groups on the surface of g-C3N4. Therefore, a modified preparation method, calcination through residual heating, was developed to achieve rapid preparation and thermal exfoliation of g-C3N4 simultaneously. Compared with pristine g-C3N4, the samples prepared by residual heating had fewer residual amino groups, a thinner 2D structure, and higher crystallinity, which led to a better photocatalytic performance. The photocatalytic degradation rate of the optimal sample for rhodamine B could reach 7.8 times higher than that of pristine g-C3N4.

14.
Nucleic Acids Res ; 38(7): 2355-68, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20047966

RESUMEN

Location analysis for estrogen receptor-alpha (ERalpha)-bound cis-regulatory elements was determined in MCF7 cells using chromatin immunoprecipitation (ChIP)-on-chip. Here, we present the estrogen response element (ERE) sequences that were identified at ERalpha-bound loci and quantify the incidence of ERE sequences under two stringencies of detection: <10% and 10-20% nucleotide deviation from the canonical ERE sequence. We demonstrate that approximately 50% of all ERalpha-bound loci do not have a discernable ERE and show that most ERalpha-bound EREs are not perfect consensus EREs. Approximately one-third of all ERalpha-bound ERE sequences reside within repetitive DNA sequences, most commonly of the AluS family. In addition, the 3-bp spacer between the inverted ERE half-sites, rather than being random nucleotides, is C(A/T)G-enriched at bona fide receptor targets. Diverse ERalpha-bound loci were validated using electrophoretic mobility shift assay and ChIP-polymerase chain reaction (PCR). The functional significance of receptor-bound loci was demonstrated using luciferase reporter assays which proved that repetitive element ERE sequences contribute to enhancer function. ChIP-PCR demonstrated estrogen-dependent recruitment of the coactivator SRC3 to these loci in vivo. Our data demonstrate that ERalpha binds to widely variant EREs with less sequence specificity than had previously been suspected and that binding at repetitive and nonrepetitive genomic targets is favored by specific trinucleotide spacers.


Asunto(s)
ADN/química , Receptor alfa de Estrógeno/metabolismo , Secuencias Repetitivas de Ácidos Nucleicos , Elementos de Respuesta , Sitios de Unión , Línea Celular Tumoral , Estradiol/farmacología , Sitios Genéticos , Humanos , Coactivador 3 de Receptor Nuclear/metabolismo , Transcripción Genética
15.
Front Plant Sci ; 13: 1014640, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36267939

RESUMEN

Maize-soybean intercropping is practiced worldwide because of some of the anticipated advantages such as high crop yield and better utilization of resources (i.e., water, light, nutrients and land). However, the shade of the maize crop has a detrimental effect on the growth and yield of soybean under the maize-soybean intercropping system. Hence, this experiment was conducted to improve the shade tolerance of such soybean crops with optimal nitrogen (N) fertilization combined with foliar application of iron (Fe) and molybdenum (Mo). The treatments comprised five (5) maize-soybean intercropping practices: without fertilizer application (F0), with N fertilizer application (F1), with N fertilizer combined with foliar application of Fe (F2), with N fertilizer coupled with foliar application of Mo (F3) and with N fertilizer combined with foliar application of Fe and Mo (F4). The findings of this study showed that maize-soybean intercropping under F4 treatment had significantly (p< 0.05) increased growth indices such as leaf area (cm2), plant height (cm), stem diameter (mm), stem strength (g pot-1), and internode length (cm) and yield indices (i.e., No of pods plant-1, grain yield (g plant-1), 100-grain weight (g), and biomass dry matter (g plant-1)) of the soybean crop. Moreover, intercropping under F4 treatment enhanced the chlorophyll SPAD values by 26% and photosynthetic activities such as Pn by 30%, gs by 28%, and Tr by 28% of the soybean crops, but reduced its CO2 by 11%. Furthermore, maize-soybean intercropping under F4 treatment showed improved efficiency of leaf chlorophyll florescence parameters of soybean crops such as Fv/Fm (26%), qp (17%), ϕPSII (20%), and ETR (17%), but reduced NPQ (12%). In addition, the rubisco activity and soluble protein content of the soybean crop increased by 18% in maize-soybean intercropping under F4 treatment. Thus, this suggested that intercropping under optimal N fertilization combined with foliar application of Fe and Mo can improve the shade tolerance of soybean crops by regulating their chlorophyll content, photosynthetic activities, and the associated enzymes, thereby enhancing their yield and yield traits.

16.
Biochemistry ; 50(5): 752-62, 2011 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-21158412

RESUMEN

RGS14 is a brain scaffolding protein that integrates G protein and MAP kinase signaling pathways. Like other RGS proteins, RGS14 is a GTPase activating protein (GAP) that terminates Gαi/o signaling. Unlike other RGS proteins, RGS14 also contains a G protein regulatory (also known as GoLoco) domain that binds Gαi1/3-GDP in cells and in vitro. Here we report that Ric-8A, a nonreceptor guanine nucleotide exchange factor (GEF), functionally interacts with the RGS14-Gαi1-GDP signaling complex to regulate its activation state. RGS14 and Ric-8A are recruited from the cytosol to the plasma membrane in the presence of coexpressed Gαi1 in cells, suggesting formation of a functional protein complex with Gαi1. Consistent with this idea, Ric-8A stimulates dissociation of the RGS14-Gαi1-GDP complex in cells and in vitro using purified proteins. Purified Ric-8A stimulates dissociation of the RGS14-Gαi1-GDP complex to form a stable Ric-8A-Gαi complex in the absence of GTP. In the presence of an activating nucleotide, Ric-8A interacts with the RGS14-Gαi1-GDP complex to stimulate both the steady-state GTPase activity of Gαi1 and binding of GTP to Gαi1. However, sufficiently high concentrations of RGS14 competitively reverse these stimulatory effects of Ric-8A on Gαi1 nucleotide binding and GTPase activity. This observation correlates with findings that show RGS14 and Ric-8A share an overlapping binding region within the last 11 amino acids of Gαi1. As further evidence that these proteins are functionally linked, native RGS14 and Ric-8A coexist within the same hippocampal neurons. These findings demonstrate that RGS14 is a newly appreciated integrator of unconventional Ric-8A and Gαi1 signaling.


Asunto(s)
Subunidades alfa de la Proteína de Unión al GTP Gi-Go/metabolismo , Guanosina Difosfato/metabolismo , Proteínas Nucleares/metabolismo , Proteínas RGS/metabolismo , Transducción de Señal , Animales , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/genética , Factores de Intercambio de Guanina Nucleótido , Guanosina Trifosfato/metabolismo , Células HeLa , Humanos , Ratones , Ratones Endogámicos C57BL , Proteínas Nucleares/genética , Unión Proteica , Proteínas RGS/genética
17.
Zhonghua Zhong Liu Za Zhi ; 33(7): 504-7, 2011 Jul.
Artículo en Zh | MEDLINE | ID: mdl-22093626

RESUMEN

OBJECTIVE: To compare the uptake of four contrast agents: (99)Tc(m)-RGD-4CK, (99)Tc(m)-N(NOET)(2), (99)Tc(m)-MIBI and (18)F-FDG in Bal B/c nude mice bearing human non-small cell lung cancer NCI-H358 and evaluate their diagnostic value in low-metabolic lung cancer. METHODS: Human bronchioloalveolar carcinoma NCI-H358 cells were subcutaneously inoculated in Bal B/c nude mice to establish mouse models bearing human lung cancer. Twenty tumor-bearing nude mice were given injection of the four contrast agent, respectively, 5 mice in each group. SPECT imaging and biodistribution of the 4 tracers in the tumor-bearing nude mice were performed. The ratios of tumor to non-tumor (T/NT) of the tracers were compared. RESULTS: The results from semi-quantification of the planar image and assessment of biodistribution showed that tumor to contralateral muscle activity ratios (T/NT) of the four tracers had statistically significant difference between each two of the four tracer groups of tumor-bearing mice (P < 0.001), with a highest value of T/NT ratio in the (99)Tc(m)-RGD-4CK group. CONCLUSIONS: NCI-H358 tumors show a higher uptake of (99)Tc(m)-RGD-4CK than (18)F-FDG. It suggests that when diagnosing a well-differentiated lung cancer such as bronchioloalveolar carcinoma, the contrast agent (99)Tc(m)-RGD-4CK may be more sensitive than (18)F-FDG, and it may become a promising contrast agent in tumor imaging diagnosis.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Medios de Contraste/farmacocinética , Neoplasias Pulmonares/diagnóstico por imagen , Tomografía Computarizada de Emisión de Fotón Único/métodos , Animales , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Femenino , Fluorodesoxiglucosa F18/farmacocinética , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Trasplante de Neoplasias , Oligopéptidos/farmacocinética , Compuestos de Organotecnecio/farmacocinética , Radiofármacos/farmacocinética , Tecnecio Tc 99m Sestamibi/farmacocinética , Tiocarbamatos/farmacocinética , Distribución Tisular
18.
Biomater Sci ; 8(21): 6100, 2020 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-33000784

RESUMEN

Correction for 'Melittin-encapsulating peptide hydrogels for enhanced delivery of impermeable anticancer peptides' by Jue-Ping Feng et al., Biomater. Sci., 2020, 8, 4559-4569, DOI: .

19.
Biomater Sci ; 8(16): 4559-4569, 2020 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-32672773

RESUMEN

Anticancer peptides (ACPs) have gained significant attention in the past few years. Most ACPs only act toward intracellular targets. However, their low membrane penetrability often limits their anticancer efficacy. Here we developed a novel melittin-RADA28 (MR) hydrogel, composed of RADA28 and melittin, through a peptide fusion method in order to promote the membrane permeability of tumor cells with the membrane-disrupting ability of melittin. As a proof of concept, we loaded the MR hydrogel with a therapeutic peptide, KLA (KLAKLAKKLAKLAK), to show the enhanced delivery efficiency of the hydrogel. Our results demonstrated that the formed melittin-RADA28-KLA peptide (MRP) hydrogel has a nanofiber structure, sustained release profile, and attenuated hemolysis effects. Compared with free KLA, the MRP hydrogel markedly increased the cellular accumulation of KLA, produced the highest ratio of the depolarized mitochondrial membrane, and decreased cell viability in vitro. Following peritumoral injection, the MRP hydrogel treatment suppressed CT26 tumor growth by more than 85%, compared to controls. In summary, we provide a facile and efficient strategy to enhance the delivery of impermeable peptides to improve their therapeutic efficiency.


Asunto(s)
Hidrogeles , Neoplasias , Supervivencia Celular , Humanos , Meliteno , Neoplasias/tratamiento farmacológico , Péptidos
20.
Front Genet ; 11: 542004, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33304378

RESUMEN

Polydactyly and syndactyly are congenital limb malformations that may occur either as non-syndromic or syndromic forms. In the present study, massively parallel sequencing was performed on a proband in a four-generation family with polydactyly and syndactyly to identify disease-causing variant(s). A pathogenic variant c.739C > T (p.Gln247∗) in the glioma-associated oncogene family zinc finger 3 (GLI3) gene was identified and co-segregated with the affected members of the family. Firstly, we examined GLI3 mRNA and GLI3 protein levels in peripheral blood mononuclear cells (PBMCs) of patients carrying this variant. The results showed that the truncated GLI3 p.Gln247∗ (c.739C > T) protein was detectable in patients and the GLI3 transcript and protein levels were not significantly altered in the PBMCs of patients compared with healthy controls. Furthermore, functional analysis showed that the truncated GLI3 p.Gln247∗ (c.739C > T) protein variant could lead to cytoplasmic accumulation of mutant protein and loss of ability to bind to the Suppressor of Fused protein. Alterations in protein expression levels of core components of the Sonic hedgehog signaling pathway were also observed. Our study shows that this novel GLI3 variant contributes to the malformations in this family and provides evidence for the mechanism by which GLI3 c.739C > T (p.Gln247∗) was implicated in the pathogenesis of polydactyly and syndactyly.

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