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1.
BMC Health Serv Res ; 24(1): 378, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38539139

RESUMEN

INTRODUCTION: Community General Practitioners (CGPs) are crucial to primary healthcare worldwide. Their job satisfaction significantly impacts the quality and accessibility of healthcare. However, a comprehensive global perspective on this issue remains absent, necessitating this systematic review and meta-analysis. METHODS: This systematic review and meta-analysis sourced literature from PubMed, Web of Science, CNKI, and Wanfang, up to June 14, 2023. Of the 2,742 identified studies, 100 articles were selected for meta-analysis to assess satisfaction levels, and 97 studies were chosen for comparative analysis of influential factors. We employed both meta-analytic and comparative analytic methodologies, focusing on varying geographical, economic, and temporal contexts. RESULTS: The pooled rate and corresponding 95% confidence interval (CI) for job satisfaction among CGPs was 70.82% (95%CI: 66.62-75.02%) globally. Studies utilizing 5-point score scale obtained a random effect size of 3.52 (95%CI: 3.43-3.61). Diverse factors influenced satisfaction, with remuneration and working conditions being predominant. A noticeable decline in job satisfaction has been observed since the coronavirus disease 2019 outbreak, with satisfaction rates dropping from an average of 72.39% before 2009 to 63.09% in those published after 2020. CONCLUSIONS: The downward trend in CGPs' job satisfaction is concerning and warrants urgent attention from policymakers, especially in regions with an acute shortage of CGPs. The findings from this comprehensive review and meta-analysis provide essential insights for informed healthcare policy-making. It highlights the urgency of implementing strategies to enhance CGP satisfaction, thereby improving the effectiveness of primary healthcare systems globally.


Asunto(s)
COVID-19 , Médicos Generales , Satisfacción en el Trabajo , Humanos , Médicos Generales/psicología , COVID-19/epidemiología , COVID-19/psicología , Atención Primaria de Salud , SARS-CoV-2 , Salud Global
2.
Anal Chem ; 95(38): 14203-14208, 2023 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-37656042

RESUMEN

Sensitive and multiple detection of the biomarkers of type 1 diabetes mellitus (T1DM) is vital to the early diagnosis and clinical treatment of T1DM. Herein, we developed a SERS-based biosensor using polyvinylidene fluoride (PVDF) membranes as a flexible support for the detection of glutamic acid decarboxylase antibodies (GADA) and insulin autoantibodies (IAA). Two kinds of silver-gold core-shell nanotags embedded with Raman probes and attached with GADA or IAA antibodies were synthesized to capture the targets, enabling highly sensitive and highly selective detection of GADA and IAA. The embedded Raman probes sandwiched between silver and gold layers guaranteed spectral stability and reliability. Moreover, the utilization of two Raman probes enables simultaneous and multiplexing detection of both GADA and IAA, improving the detection accuracy for T1DM. The proposed SERS-based method has been proven feasible for clinical sample detection, demonstrating its great potential in sensitive, reliable, and rapid diagnosis of T1DM.


Asunto(s)
Técnicas Biosensibles , Diabetes Mellitus Tipo 1 , Nanopartículas del Metal , Humanos , Diabetes Mellitus Tipo 1/diagnóstico , Plata , Reproducibilidad de los Resultados , Biomarcadores , Anticuerpos , Oro , Espectrometría Raman/métodos
3.
Bioorg Chem ; 138: 106650, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37302314

RESUMEN

As one of the important members of reactive oxygen species, ONOO- plays a crucial role in signal transduction, immune response, and other physiological activities. Aberrant changes in ONOO- levels in the living organism are usually associated with many diseases. Therefore, it is important to establish a highly selective and sensitive method for the determination of ONOO- in vivo. Herein, we designed a novel ratio near-infrared fluorescent probe for ONOO- by directly conjugating dicyanoisophorone (DCI) to hydroxyphenyl-quinazolinone (HPQ). Surprisingly, HPQD was unaffected by environmental viscosity and responded rapidly to ONOO- within 40 s. The linear range of ONOO- detection was from 0 µM to 35 µM. Impressively, HPQD did not react with reactive oxygen species and was sensitive to exogenous/endogenous ONOO- in live cells. We also investigated the relationship between ONOO- and ferroptosis and achieved in vivo diagnosis and efficacy evaluation of mice model of LPS-induced inflammation, which showed promising prospects of HPQD in ONOO--related studies.


Asunto(s)
Ferroptosis , Colorantes Fluorescentes , Ratones , Animales , Ácido Peroxinitroso , Lipopolisacáridos/farmacología , Especies Reactivas de Oxígeno , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Modelos Animales de Enfermedad
4.
Molecules ; 28(11)2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37298934

RESUMEN

Zinc-ion batteries (ZIBs) have recently attracted great interest and are regarded as a promising energy storage device due to their low cost, environmental friendliness, and superior safety. However, the development of suitable Zn-ion intercalation cathode materials remains a great challenge, resulting in unsatisfactory ZIBs that cannot meet commercial demands. Considering that spinel-type LiMn2O4 has been shown to be a successful Li intercalation host, spinel-like ZnMn2O4 (ZMO) is expected to be a good candidate for ZIBs cathodes. This paper first introduces the zinc storage mechanism of ZMO and then reviews the promotion of research progress in improving the interlayer spacing, structural stability, and diffusivity of ZMO, including the introduction of different intercalated ions, introduction of defects, and design of different morphologies and in combination with other materials. The development status and future research directions of ZMO-based ZIBs characterization and analysis techniques are summarized.


Asunto(s)
Tecnología , Zinc , Electrodos , Iones
5.
Cryobiology ; 105: 1-9, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35065926

RESUMEN

The aim of this study was to investigate the effects of freeze-drying protective agents on the viability, survival and membrane fatty acid composition of Lactobacillus plantarum L1 and Lactobacillus fermentum L2. Cell survival rates of Lactobacillus plantarum L1 after freeze-drying without any additives was 6.57% (control group), 37.4% with a single protective agent, as compared to 97.4% when L.plantarum L1 was freeze-dried in a solution of four protectants (10% skim milk, 13% sucrose, 2% sorbitol, and 0.8% tyrosine (p < 0.05).) The L.fermentum L2 strain had the highest survival rate 92.3% when was freeze-dried in a solution containing 10% skim milk, 7% trehalose, 2% sorbitol and 0.6% tyrosine (p < 0.05). Freeze drying in the presence of all four protective agents maintained cell membrane integrity, as determined by reduced leakage of ß-galactosidase and LDH, and increased ATPase activity. LAB Incubation and freeze drying in the complex protective solution increased the content of unsaturated fatty acids in the cell membrane such as oleic acid (C18:1) and C19cyc11 and it is speculated that this may correlate with the improved outcomes.


Asunto(s)
Lactobacillus plantarum , Limosilactobacillus fermentum , Criopreservación/métodos , Crioprotectores/metabolismo , Crioprotectores/farmacología , Ácidos Grasos/metabolismo , Liofilización , Lactobacillus plantarum/metabolismo , Sorbitol/metabolismo , Tirosina/metabolismo
6.
Anal Chem ; 93(4): 2490-2499, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33433198

RESUMEN

Epilepsy is a chronic neurodegenerative disease that has seriously threatened human health. Accumulating evidence reveals that the pathological progression of epilepsy is closely related to peroxynitrite (ONOO-). Unfortunately, understanding the physiological roles of ONOO- in epilepsy is still challenging due to the lack of powerful imaging probes for the determination of the level of fluctuations of ONOO- in the epileptic brain. Herein, a near-infrared (NIR) two-photon (TP) fluorescent probe [dicyanomethylene-4H-pyran (DCM)-ONOO] is presented to trace ONOO- in living cells and in kainate (KA)-induced rat epilepsy models with satisfactory sensitivity and selectivity. The probe is composed of a NIR TP DCM fluorophore and a recognition moiety diphenylphosphinamide. The phosphoramide bond of the probe is interrupted after reacting with ONOO- for 10 min, and then, the released amino groups emit strong fluorescence due to the restoration of the intramolecular charge transfer process. The probe can effectively detect the changes of endogenous ONOO- with excellent temporal and spatial resolution in living cells and in rat epileptic brain. The imaging results demonstrate that the increasing level of ONOO- is closely associated with epilepsy and severe neuronal damage in the brain under KA stimulation. In addition, the low-dose resveratrol can effectively inhibit ONOO- overexpression and further relieve neuronal damage. With the assistance of TP fluorescence imaging in the epileptic brain tissue, we hypothesize that the abnormal levels of ONOO- may serve as a potential indicator for the diagnosis of epilepsy. The TP fluorescence imaging based on DCM-ONOO provides a great potential approach for understanding the epilepsy pathology and diagnosis.


Asunto(s)
Epilepsia/inducido químicamente , Epilepsia/metabolismo , Colorantes Fluorescentes/química , Ácido Peroxinitroso/metabolismo , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Ácido Kaínico/toxicidad , Ratones , Estructura Molecular , Ratas , Ratas Sprague-Dawley
7.
Mol Biol Rep ; 48(8): 5847-5855, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34370208

RESUMEN

BACKGROUND: The mitogen-activated protein kinase (MAPK) cascades play important roles in various signaling transduction networks of biotic and abiotic stress responses. However, MAPK signaling pathways in cold-active yeast Rhodotorula mucilaginosa have not been reported comprehensively. METHODS AND RESULTS: In the present study, MAPK gene (RmMAPK) was first cloned and characterized from Antarctic sea ice yeast R. mucilaginosa AN5. The full length of the RmMAPK gene is 1086 bp and encodes a 361 amino acids protein with a predicted molecular mass of 40.9 kDa and a pI of 5.25. The RmMAPK contains 11 MAPK conserved subdomains and the phosphorylation motif TGY located in the activation loop of the kinase. Quantitative real-time PCR and western blot assay revealed that the expression and phosphorylation level of RmMAPK up-regulated rapidly and significantly when yeast cells were subjected to low temperature (4 °C), high salinity (120‰ NaCl) and heavy metal (2 mmol/L CuCl2). CONCLUSIONS: All data suggested that the MAPK cascades might act as a key function in response to extreme stresses, such as low temperature, high salinity and heavy metal.


Asunto(s)
Clonación Molecular/métodos , Proteínas Quinasas Activadas por Mitógenos/genética , Rhodotorula/genética , Secuencia de Aminoácidos/genética , Sistema de Señalización de MAP Quinasas/genética , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Proteínas de Plantas/genética , Rhodotorula/metabolismo , Análisis de Secuencia de ADN/métodos
8.
J Exp Bot ; 71(6): 1943-1955, 2020 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-31858133

RESUMEN

Vacuolar processing enzyme (VPE) is responsible for the maturation and activation of vacuolar proteins in plants. We found that ßVPE was involved in tapetal degradation and pollen development by transforming proproteases into mature protease in Arabidopsis thaliana. ßVPE was expressed specifically in the tapetum from stages 5 to 8 of anther development. The ßVPE protein first appeared as a proenzyme and was transformed into the mature enzyme before stages 7-8. The recombinant ßVPE protein self-cleaved and transformed into a 27 kDa mature protein at pH 5.2. The mature ßVPE protein could induce the maturation of CEP1 in vitro. ßvpe mutants exhibited delayed vacuolar degradation and decreased pollen fertility. The maturation of CEP1, RD19A, and RD19C was seriously inhibited in ßvpe mutants. Our results indicate that ßVPE is a crucial processing enzyme that directly participates in the maturation of cysteine proteases before vacuolar degradation, and is indirectly involved in pollen development and tapetal cell degradation.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , Cisteína Endopeptidasas , Proteasas de Cisteína , Polen , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteasas de Cisteína/genética , Proteasas de Cisteína/metabolismo , Regulación de la Expresión Génica de las Plantas , Polen/genética , Polen/metabolismo , Vacuolas/metabolismo
9.
J Exp Bot ; 70(1): 205-215, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30376110

RESUMEN

Both tracheary elements and fiber cells undergo programmed cell death (PCD) during xylem development. In this study we investigated the role of papain-like cysteine protease CEP1 in PCD in the xylem of Arabidopsis. CEP1 was located in the cell wall of xylem cells, and CEP1 expression levels in inflorescence stems increased during stem maturation. cep1 mutant plants exhibited delayed stem growth and reduced xylem cell number compared to wild-type plants. Transmission electron microscopy demonstrated that organelle degradation was delayed during PCD, and thicker secondary walls were present in fiber cells and tracheary elements of the cep1 mutant. Transcriptional analyses of the maturation stage of the inflorescence stem revealed that genes involved in the biosynthesis of secondary wall components, including cellulose, hemicellulose, and lignin, as well as wood-associated transcriptional factors, were up-regulated in the cep1 mutant. These results suggest that CEP1 is directly involved in the clearing of cellular content during PCD and regulates secondary wall thickening during xylem development.


Asunto(s)
Apoptosis/genética , Arabidopsis/fisiología , Pared Celular/genética , Cisteína Endopeptidasas/genética , Xilema/crecimiento & desarrollo , Arabidopsis/genética , Arabidopsis/crecimiento & desarrollo , Arabidopsis/metabolismo , Pared Celular/metabolismo , Cisteína Endopeptidasas/metabolismo , Regulación de la Expresión Génica de las Plantas , Xilema/genética
10.
Br J Nutr ; 121(11): 1279-1286, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30837009

RESUMEN

Maternal one-carbon metabolism during pregnancy is crucial for fetal development and programming by DNA methylation. However, evidence on one-carbon biomarkers other than folate is lacking. We, therefore, investigated whether maternal plasma methyl donors, that is, choline, betaine and methionine, are associated with birth outcomes. Blood samples were obtained from 115 women during gestation (median 26·3 weeks, 90 % range 22·7-33·0 weeks). Plasma choline, betaine, methionine and dimethylglycine were measured using HPLC-tandem MS. Multivariate linear and logistic regression models were used to estimate the association between plasma biomarkers and birth weight, birth length, the risk of small-for-gestational-age and large-for-gestational-age (LGA). Higher level of maternal betaine was associated with lower birth weight (-130·3 (95 % CI -244·8, -15·9) per 1 sd increment for log-transformed betaine). Higher maternal methionine was associated with lower risk of LGA, and adjusted OR, with 95 % CI for 1 sd increase in methionine concentration was 0·44 (95 % CI 0·21, 0·89). Stratified analyses according to infant sex or maternal plasma homocysteine status showed that reduction in birth weight in relation to maternal betaine was only limited to male infants or to who had higher maternal homocysteine status (≥5·1 µmol/l). Higher maternal betaine status was associated with reduced birth weight. Maternal methionine was inversely associated with LGA risk. These findings are needed to be replicated in future larger studies.


Asunto(s)
Betaína/sangre , Peso al Nacer , Fenómenos Fisiologicos Nutricionales Maternos/fisiología , Trimestres del Embarazo/sangre , Adulto , Colina/sangre , Femenino , Homocisteína/sangre , Humanos , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Masculino , Metionina/sangre , Embarazo , Sarcosina/análogos & derivados , Sarcosina/sangre
11.
Analyst ; 144(22): 6533-6540, 2019 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-31553332

RESUMEN

Cardiac troponin I (cTnI) and creatine kinase-MB (CK-MB) are important diagnostic biomarkers for acute myocardial infarction (AMI). Many efforts have been undertaken to develop highly sensitive detection methods for the quantitative analysis of these dual targets. However, current immunoassay methods are inadequate for accurate measurement of cTnI and CK-MB, due to their limited detection sensitivity. Thus, there is still an urgent demand for a new technique that will enable ultrahigh sensitive detection of these biomarkers. In this study, we developed a surface-enhanced Raman scattering (SERS)-based sandwich immunoassay platform for the ultrasensitive detection of cTnI and CK-MB. In this study, a monoclonal-antibody-immobilized gold-patterned chip was used as a SERS active template. Target samples and polyclonal-antibody-conjugated Au@Ag core-shell nanoparticles were then added. Using this SERS platform, the concentration of biomarkers could be quantified by monitoring the characteristic Raman peak intensity of Raman reporter molecules. Under optimized conditions, the limits of detection (LODs) were estimated to be 8.9 pg mL-1 and 9.7 pg mL-1 for cTnI and CK-MB, respectively. Thus, the proposed SERS-based immunoassay has great potential to be an effective diagnostic tool for the rapid and accurate detection of cTnI and CK-MB.


Asunto(s)
Forma MB de la Creatina-Quinasa/análisis , Inmunoensayo/métodos , Nanopartículas del Metal/química , Infarto del Miocardio/diagnóstico , Troponina I/análisis , Enfermedad Aguda , Anticuerpos Inmovilizados/inmunología , Anticuerpos Monoclonales/inmunología , Biomarcadores/análisis , Forma MB de la Creatina-Quinasa/inmunología , Oro/química , Humanos , Límite de Detección , Reproducibilidad de los Resultados , Plata/química , Espectrometría Raman/métodos , Troponina I/inmunología
12.
Int J Mol Sci ; 20(14)2019 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-31337083

RESUMEN

Histone acetylation and deacetylation play essential roles in eukaryotic gene regulation. HD2 (HD-tuins) proteins were previously identified as plant-specific histone deacetylases. In this study, we investigated the function of the HDT1 gene in the formation of stem vascular tissue in Arabidopsis thaliana. The height and thickness of the inflorescence stems in the hdt1 mutant was lower than that of wild-type plants. Paraffin sections showed that the cell number increased compared to the wild type, while transmission electron microscopy showed that the size of individual tracheary elements and fiber cells significantly decreased in the hdt1 mutant. In addition, the cell wall thickness of tracheary elements and fiber cells increased. We also found that the lignin content in the stem of the hdt1 mutants increased compared to that of the wild type. Transcriptomic data revealed that the expression levels of many biosynthetic genes related to secondary wall components, including cellulose, lignin biosynthesis, and hormone-related genes, were altered, which may lead to the altered phenotype in vascular tissue of the hdt1 mutant. These results suggested that HDT1 is involved in development of the vascular tissue of the stem by affecting cell proliferation and differentiation.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Histona Desacetilasas/genética , Desarrollo de la Planta/genética , Tallos de la Planta/genética , Haz Vascular de Plantas/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Pared Celular/genética , Pared Celular/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Histona Desacetilasas/metabolismo , Lignina/metabolismo , Mutación , Fenotipo , Tallos de la Planta/metabolismo , Haz Vascular de Plantas/metabolismo , Xilema/citología , Xilema/genética , Xilema/metabolismo
14.
Anal Chem ; 89(2): 1163-1169, 2017 01 17.
Artículo en Inglés | MEDLINE | ID: mdl-28194991

RESUMEN

A new class of surface-enhanced Raman scattering (SERS)-based lateral flow assay (LFA) biosensor has been developed for the simultaneous detection of dual DNA markers. The LFA strip in this sensor was composed of two test lines and one control line. SERS nano tags labeled with detection DNA probes were used for quantitative evaluation of dual DNA markers with high sensitivity. Target DNA, associated with Kaposi's sarcoma-associated herpesvirus (KSHV) and bacillary angiomatosis (BA), were tested to validate the detection capability of this SERS-based LFA strip. Characteristic peak intensities of SERS nano tags on two test lines were used for quantitative evaluations of KSHV and BA. The limits of detection for KSHV and BA, determined from our SERS-based LFA sensing platform, were estimated to be 0.043 and 0.074 pM, respectively. These values indicate approximately 10 000 times higher sensitivity than previously reported values using the aggregation-based colorimetric method. We believe that this is the first report of simultaneous detection of two different DNA mixtures using a SERS-based LFA platform. This novel detection technique is also a promising multiplex DNA sensing platform for early disease diagnosis.


Asunto(s)
Angiomatosis Bacilar/microbiología , Técnicas Biosensibles/instrumentación , ADN/análisis , Infecciones por Herpesviridae/virología , Herpesvirus Humano 8/aislamiento & purificación , Espectrometría Raman/instrumentación , Bartonella henselae/genética , Bartonella henselae/aislamiento & purificación , ADN/genética , Sondas de ADN/química , Sondas de ADN/genética , ADN Bacteriano/análisis , ADN Bacteriano/genética , ADN Viral/análisis , ADN Viral/genética , Diseño de Equipo , Herpesvirus Humano 8/genética , Humanos , Tiras Reactivas/análisis
15.
Eur J Neurosci ; 44(2): 1878-85, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27062560

RESUMEN

Depression is a major neuropsychiatric disorder that exerts deleterious effects upon public health. However, the neuronal mechanisms of depression remain largely uncharacterized, which has retarded the identification and development of effective therapeutic tools for the treatment of this disorder. The aim of this study was to explore the neuronal mechanisms underlying the protective effects of ginsenoside Rg1, a natural steroidal saponin found in ginseng, against chronic stress-induced depression.The results showed that chronic administration of ginsenoside Rg1 (40 mg/kg, i.p., 5 weeks) significantly ameliorated depression-like behaviours in rats as assessed in the sucrose preference and forced swim tests. Furthermore, chronic stress decreased the phosphorylation levels of the extracellular signal-regulated kinase and cAMP-response element-binding protein in the prefrontal cortex as well as producing a reduction of brain-derived neurotrophic factor expression. Of particular importance, all reductions in these parameters were significantly reversed by pre-treatment with ginsenoside Rg1. Taken together, the results of the present study suggest that the antidepressant-like effect of ginsenoside Rg1 might be mediated, at least in part, by activating the cAMP-response element-binding protein-brain-derived neurotrophic factor system within the prefrontal cortex. These findings not only reveal some of the underlying neuronal mechanisms of depression, but also the therapeutic potential of ginsenoside Rg1 as a preventive agent in the treatment of depression.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/metabolismo , Fármacos del Sistema Nervioso Central/farmacología , Depresión/tratamiento farmacológico , Ginsenósidos/farmacología , Corteza Prefrontal/efectos de los fármacos , Estrés Psicológico/tratamiento farmacológico , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Fármacos del Sistema Nervioso Central/administración & dosificación , Fármacos del Sistema Nervioso Central/uso terapéutico , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Depresión/etiología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Ginsenósidos/administración & dosificación , Ginsenósidos/uso terapéutico , Masculino , Corteza Prefrontal/metabolismo , Corteza Prefrontal/fisiología , Ratas , Ratas Wistar , Estrés Psicológico/complicaciones
16.
ACS Synth Biol ; 13(7): 2081-2090, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-38607270

RESUMEN

Ectoine is a compatible solute that functions as a cell protector from various stresses, protecting cells and stabilizing biomolecules, and is widely used in medicine, cosmetics, and biotechnology. Microbial fermentation has been widely used for the large-scale production of ectoine, and a number of fermentation strategies have been developed to increase the ectoine yield, reduce production costs, and simplify the production process. Here, Corynebacterium glutamicum was engineered for ectoine production by heterologous expression of the ectoine biosynthesis operon ectBAC gene from Halomonas elongata, and a series of genetic modifications were implemented. This included introducing the de3 gene from Escherichia coli BL21 (DE3) to express the T7 promoter, eliminating the lysine transporter protein lysE to limit lysine production, and performing a targeted mutation lysCS301Y on aspartate kinase to alleviate feedback inhibition of lysine. The new engineered strain Ect10 obtained an ectoine titer of 115.87 g/L in an optimized fed-batch fermentation, representing the highest ectoine production level in C. glutamicum and achieving the efficient production of ectoine in a low-salt environment.


Asunto(s)
Aminoácidos Diaminos , Corynebacterium glutamicum , Escherichia coli , Fermentación , Halomonas , Ingeniería Metabólica , Aminoácidos Diaminos/biosíntesis , Aminoácidos Diaminos/metabolismo , Aminoácidos Diaminos/genética , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Ingeniería Metabólica/métodos , Halomonas/genética , Halomonas/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Lisina/metabolismo , Lisina/biosíntesis , Regiones Promotoras Genéticas , Operón/genética , Aspartato Quinasa/genética , Aspartato Quinasa/metabolismo , Sistemas de Transporte de Aminoácidos Básicos
17.
J Colloid Interface Sci ; 673: 679-689, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38901358

RESUMEN

Photodynamic therapy (PDT) is an emerging treatment but often restricted by the availability of oxygen. Enhancing the lifespan of singlet oxygen (1O2) by fractionated generation is an effective approach to improve the efficacy of PDT. Herein, an imine-based nanoscale COF (TpDa-COF) has been synthesized and functionalized with a pyridone-derived structure (Py) to create a 1O2-storing nanoplatform TpDa-COF@Py, which can reversibly capture and release 1O2. Under 660 nm laser exposure, Py interacts with 1O2 produced by the porphyrin motif in COF backbones to generate 1O2-enriched COF (TpDa-COF@Py + hv), followed by the release of 1O2 through retro-Diels-Alder reactions at physiological temperatures. The continuous producing and releasing of 1O2 upon laser exposure leads to an "afterglow" effect and a prolonged 1O2 lifespan. In vitro cytotoxicity assays demonstrates that TpDa-COF@Py + hv exhibits an extremely low half-maximal inhibitory concentration (IC50) of 0.54 µg/mL on 4T1 cells. Remarkably, the Py-mediated TpDa-COF@Py nanoplatform demonstrates enhanced cell-killing capability under laser exposure, attributed to the sustained 1O2 cycling, compared to TpDa-COF alone. Further in vivo assessment highlights the potential of TpDa-COF@Py + hv as a promising strategy to enhance phototheronostics and achieve effective tumor regression. Accordingly, the study supplies a generalized 1O2 "afterglow" nanoplatform to improve the effectiveness of PDT.


Asunto(s)
Supervivencia Celular , Estructuras Metalorgánicas , Fotoquimioterapia , Fármacos Fotosensibilizantes , Oxígeno Singlete , Oxígeno Singlete/metabolismo , Oxígeno Singlete/química , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/síntesis química , Animales , Ratones , Supervivencia Celular/efectos de los fármacos , Estructuras Metalorgánicas/química , Estructuras Metalorgánicas/farmacología , Estructuras Metalorgánicas/síntesis química , Antineoplásicos/farmacología , Antineoplásicos/química , Tamaño de la Partícula , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Estructura Molecular , Propiedades de Superficie , Humanos , Proliferación Celular/efectos de los fármacos , Femenino , Ratones Endogámicos BALB C
18.
J Exp Clin Cancer Res ; 43(1): 35, 2024 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-38287371

RESUMEN

BACKGROUND: Hepatocellular Carcinoma (HCC) is a matter of great global public health importance; however, its current therapeutic effectiveness is deemed inadequate, and the range of therapeutic targets is limited. The aim of this study was to identify early growth response 1 (EGR1) as a transcription factor target in HCC and to explore its role and assess the potential of gene therapy utilizing EGR1 for the management of HCC. METHODS: In this study, both in vitro and in vivo assays were employed to examine the impact of EGR1 on the growth of HCC. The mouse HCC model and human organoid assay were utilized to assess the potential of EGR1 as a gene therapy for HCC. Additionally, the molecular mechanism underlying the regulation of gene expression and the suppression of HCC growth by EGR1 was investigated. RESULTS: The results of our investigation revealed a notable decrease in the expression of EGR1 in HCC. The decrease in EGR1 expression promoted the multiplication of HCC cells and the growth of xenografted tumors. On the other hand, the excessive expression of EGR1 hindered the proliferation of HCC cells and repressed the development of xenografted tumors. Furthermore, the efficacy of EGR1 gene therapy was validated using in vivo mouse HCC models and in vitro human hepatoma organoid models, thereby providing additional substantiation for the anti-cancer role of EGR1 in HCC. The mechanistic analysis demonstrated that EGR1 interacted with the promoter region of phosphofructokinase-1, liver type (PFKL), leading to the repression of PFKL gene expression and consequent inhibition of PFKL-mediated aerobic glycolysis. Moreover, the sensitivity of HCC cells and xenografted tumors to sorafenib was found to be increased by EGR1. CONCLUSION: Our findings suggest that EGR1 possesses therapeutic potential as a tumor suppressor gene in HCC, and that EGR1 gene therapy may offer benefits for HCC patients.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Humanos , Ratones , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/metabolismo , Línea Celular Tumoral , Proliferación Celular , Proteína 1 de la Respuesta de Crecimiento Precoz/genética , Proteína 1 de la Respuesta de Crecimiento Precoz/metabolismo , Regulación Neoplásica de la Expresión Génica , Glucólisis , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/metabolismo , Sorafenib/farmacología
19.
Biosens Bioelectron ; 261: 116467, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38901392

RESUMEN

Light therapy is an effective approach for the treatment of a variety of challenging dermatological conditions. In contrast to existing methods involving high doses and large areas of illumination, alternative strategies based on wearable designs that utilize a low light dose over an extended period provide a precise and convenient treatment. In this study, we present a battery-free, skin-integrated optoelectronic patch that incorporates a coil-powered circuit, an array of microscale violet and red light emitting diodes (LEDs), and polymer microneedles (MNs) loaded with 5-aminolevulinic acid (5-ALA). These polymer MNs, based on the biodegradable composite materials of polyvinyl alcohol (PVA) and hyaluronic acid (HA), serve as light waveguides for optical access and a medium for drug release into deeper skin layers. Unlike conventional clinical photomedical appliances with a rigid and fixed light source, this flexible design allows for a conformable light source that can be applied directly to the skin. In animal models with bacterial-infected wounds, the experimental group with the combination treatment of metronomic photodynamic and light therapies reduced 2.48 log10 CFU mL-1 in bactericidal level compared to the control group, indicating an effective anti-infective response. Furthermore, post-treatment analysis revealed the activation of proregenerative genes in monocyte and macrophage cell populations, suggesting enhanced tissue regeneration, neovascularization, and dermal recovery. Overall, this optoelectronic patch design broadens the scope for targeting deep skin lesions, and provides an alternative with the functionality of standard clinical light therapy methods.


Asunto(s)
Fotoquimioterapia , Animales , Fotoquimioterapia/métodos , Ratones , Humanos , Alcohol Polivinílico/química , Ácido Aminolevulínico/uso terapéutico , Ácido Aminolevulínico/farmacología , Ácido Aminolevulínico/química , Ácido Aminolevulínico/administración & dosificación , Técnicas Biosensibles , Ácido Hialurónico/química , Infección de Heridas/tratamiento farmacológico , Infección de Heridas/microbiología , Infección de Heridas/terapia , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Piel/efectos de la radiación , Piel/microbiología , Diseño de Equipo
20.
Sci Total Environ ; 890: 164510, 2023 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-37257595

RESUMEN

Although increasing attention has been paid to agronomic measures for reducing the heavy metal load in rice grain, the effects of duckweed-paddy co-cropping technology on the accumulation of cadmium (Cd) in rice grains remain unclear. To investigate its specific effects on Cd accumulation in paddy fields, three types of duckweed-like hydrophyte (DH), Azolla imbricata, Spirodela polyrrhiza, and Lemna minor were chosen for study. Their use resulted in a reduction of Cd content in rice grains from 0.40 mg/kg to <0.20 mg/kg, with A. imbricata yielding the best results (0.15 mg/kg). The three types of DH reduced the available Cd content in the soil by 10 % to 35 % after the paddy tillering stage. The reduction of available Cd content was attributed to the absorption, high pH, and increase of relative abundance of special bacteria of immobilizing Cd. In addition, DH could regulate soil nitrogen leading to ammonium nitrogen increased from 75 mg/kg to 100 mg/kg, while nitrate nitrogen decreased from 0.55 to 0.1-0.3 mg/kg. The increase of ammonium nitrogen content might induce the low Cd transfer ability in rice plant and then low Cd content in rice grain. This study demonstrated that DH has a good effect on the reduction of the Cd concentration in rice grains. Consequently, duckweed-paddy co-cropping technology offers a potential solution to heavy metal pollution and agricultural non-point source pollution, as it not only reduces Cd levels in rice plants, but also fixes nitrogen, reducing the need for nitrogen application.


Asunto(s)
Compuestos de Amonio , Oryza , Contaminantes del Suelo , Cadmio/análisis , Oryza/química , Amoníaco , Adsorción , Contaminantes del Suelo/análisis , Suelo/química
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