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1.
Glob Heart ; 19(1): 25, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38434155

RESUMO

Background: It is unclear whether serum calcium on admission is associated with clinical outcomes in dilated cardiomyopathy (DCM). In this study, we conducted a retrospective study spanning a decade to investigate the prognostic value of baseline calcium in elderly patients with DCM. Methods: A total of 1,089 consecutive elderly patients (age ≥60 years) diagnosed with DCM were retrospectively enrolled from January 2010 to December 2019. Univariate and multivariate analyses were performed to investigate the association of serum calcium with their clinical outcomes. Results: In this study, the average age of the subjects was 68.36 ± 6.31 years. Receiver operating characteristic (ROC) curve analysis showed that serum calcium level had a great sensitivity and specificity for predicting in-hospital death, with an AUC of 0.732. Kaplan-Meier survival analysis showed that patients with a serum calcium >8.62 mg/dL had a better prognosis than those with a serum calcium ≤8.62 mg/dL (log-rank χ2 40.84, p < 0.001). After adjusting for several common risk factors, a serum calcium ≤8.62 mg/dL was related to a higher risk of long-term mortality (HR: 1.449; 95% CI: 1.115~1.882; p = 0.005). Conclusions: Serum calcium level could be served as a simple and affordable tool to evaluate patients' prognosis in DCM.


Assuntos
Cálcio , Cardiomiopatia Dilatada , Idoso , Humanos , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Cardiomiopatia Dilatada/diagnóstico , Mortalidade Hospitalar
2.
Molecules ; 28(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38138468

RESUMO

A large quantity of coal fly ash is generated worldwide from thermal power plants, causing a serious environmental threat owing to disposal and storage problems. In this work, for the first time, coal fly ash is converted into advanced and novel aerogel fibers and high-purity α-Al2O3. Silica-bacterial cellulose composite aerogel fibers (CAFs) were synthesized using an in situ sol-gel process under ambient pressure drying. Due to the unique "nanoscale interpenetrating network" (IPN) structure, the CAFs showed wonderful mechanical properties with an optimum tensile strength of 5.0 MPa at an ultimate elongation of 5.8%. Furthermore, CAFs with a high porosity (91.8%) and high specific surface area (588.75 m2/g) can inherit advanced features, including excellent thermal insulation, stability over a wide temperature range, and hydrophobicity (contact angle of approximately 144°). Additionally, Al2O3 was simultaneously extracted from the coal fly ash to ensure that the coal fly ash was fully exploited. Overall, low-cost woven CAFs fabrics are suitable for wearable applications and offer a great approach to comprehensively use coal fly ash to address environmental threats.

3.
Sci Rep ; 13(1): 12823, 2023 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-37550374

RESUMO

Drought stress can severely affect sugarcane growth and yield. The objective of this research was to identify candidate genes in sugarcane tillering seedlings in response to drought stress. We performed a comparative phenotypic, physiological and transcriptomic analysis of tiller seedlings of drought-stressed and well-watered "Guire 2" sugarcane, in a time-course experiment (5 days, 9 days and 15 days). Physiological examination reviewed that SOD, proline, soluble sugars, and soluble proteins accumulated in large amounts in tiller seedlings under different intensities of drought stress, while MDA levels remained at a stable level, indicating that the accumulation of osmoregulatory substances and the enhancement of antioxidant enzyme activities helped to limit further damage caused by drought stress. RNA-seq and weighted gene co-expression network analysis (WGCNA) were performed to identify genes and modules associated with sugarcane tillering seedlings in response to drought stress. Drought stress induced huge down-regulated in gene expression profiles, most of down-regulated genes were mainly associated with photosynthesis, sugar metabolism and fatty acid synthesis. We obtained four gene co-expression modules significantly associated with the physiological changes under drought stress (three modules positively correlated, one module negatively correlated), and found that LSG1-2, ERF1-2, SHKA, TIL, HSP18.1, HSP24.1, HSP16.1 and HSFA6A may play essential regulatory roles as hub genes in increasing SOD, Pro, soluble sugar or soluble protein contents. In addition, one module was found mostly involved in tiller stem diameter, among which members of the BHLH148 were important nodes. These results provide new insights into the mechanisms by which sugarcane tillering seedlings respond to drought stress.


Assuntos
Saccharum , Transcriptoma , Plântula/genética , Saccharum/genética , Secas , Superóxido Dismutase/genética , Estresse Fisiológico/genética
4.
Phytomedicine ; 114: 154774, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36996530

RESUMO

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is currently the third leading cause of death globally. Oxidative stress affects various molecular mechanisms and is the main driving factor of COPD. Ally isothiocyanate (AITC) is an effective component of Semen Sinapis Albae, which has favorable effects for the treatment of COPD, but its mechanism has not been fully elucidated. PURPOSE: This study aimed to elucidate the antioxidant effect of AITC on COPD and its molecular mechanism, and preliminarily determine the role of AhR in the progression of COPD. STUDY DESIGN: The COPD rat model was established by smoking combined with intratracheal instillation of lipopolysaccharide. Different doses of AITC, positive control drug acetylcysteine, AhR inhibitor alpha-naphthoflavone, and agonist beta-naphthoflavone were administered by gavage. Human bronchial epithelial cells induced by cigarette smoke extract (CSE) were used in an in vitro model to explore the molecular mechanisms of AITC. METHODS: The effects of AITC on lung function and oxidative stress in rats were evaluated in vivo using the respiratory function test, white blood cell count, enzyme-linked immunosorbent assay, and histological staining. The changes in protein expression in the lung tissue were detected by immunohistochemistry and Western blotting. RT-PCR, western blotting, and immunofluorescence were used to explore the molecular mechanisms of AITC. Enzyme-linked immunosorbent assay, reactive oxygen species probing, and flow cytometry were used to determine the antioxidant effect of AITC. RESULTS: AITC can improve the lung function of rats with COPD, restore lung tissue structure, improve oxidative stress, reduce inflammation, and inhibit lung cell apoptosis. AITC reversed the upregulation of AhR and CYP1A1 and the down-regulation of Nrf2 and NQO1 in the lung tissues of rats with COPD. CSE stimulation can increase the expressions of AhR and CYP1A1 and decrease the expressions of Nrf2 and NQO1 in 16HBE cells, leading to severe oxidative stress and inflammatory response and, ultimately, apoptosis. AITC inhibited AhR and CYP1A1 expressions, induced Nrf2 and NQO1 expressions, promoted Nrf2 nuclear translocation, and improved CSE-induced toxicological effects. CONCLUSION: AITC may improve lung oxidative stress by inhibiting the AhR / CYP1A1 and activating the Nrf2 / NQO1 pathways, thereby delaying the pathological progression of COPD.


Assuntos
Fator 2 Relacionado a NF-E2 , Doença Pulmonar Obstrutiva Crônica , Ratos , Humanos , Animais , Fator 2 Relacionado a NF-E2/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Antioxidantes/farmacologia , Transdução de Sinais , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Isotiocianatos/farmacologia , Estresse Oxidativo , NAD(P)H Desidrogenase (Quinona)/metabolismo
5.
ACS Appl Mater Interfaces ; 15(14): 18101-18113, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36989425

RESUMO

In recent years, two-dimensional (2D) nonlayered Bi2O2Se-based electronics and optoelectronics have drawn enormous attention owing to their high electron mobility, facile synthetic process, stability to the atmosphere, and moderate narrow band gaps. However, 2D Bi2O2Se-based photodetectors typically present large dark current, relatively slow response speed, and persistent photoconductivity effect, limiting further improvement in fast-response imaging sensors and low-consumption broadband detection. Herein, a Bi2O2Se/2H-MoTe2 van der Waals (vdWs) heterostructure obtained from the chemical vapor deposition (CVD) approach and vertical stacking is reported. The proposed type-II staggered band alignment desirable for suppression of dark current and separation of photoinduced carriers is confirmed by density functional theory (DFT) calculations, accompanied by strong interlayer coupling and efficient built-in potential at the junction. Consequently, a stable visible (405 nm) to near-infrared (1310 nm) response capability, a self-driven prominent responsivity (R) of 1.24 A·W-1, and a high specific detectivity (D*) of 3.73 × 1011 Jones under 405 nm are achieved. In particular, R, D*, fill factor, and photoelectrical conversion efficiency (PCE) can be enhanced to 4.96 A·W-1, 3.84 × 1012 Jones, 0.52, and 7.21% at Vg = -60 V through a large band offset originated from the n+-p junction. It is suggested that the present vdWs heterostructure is a promising candidate for logical integrated circuits, image sensors, and low-power consumption detection.

6.
Acta Pharmacol Sin ; 44(6): 1262-1276, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36482085

RESUMO

Malignant glioma is the most fatal, invasive brain cancer with limited treatment options. Our previous studies show that 2-(indol-3-ylmethyl)-3,3'-diindolylmethane (LTr1), a major metabolite of indole-3-carbinol (I3C) derived from cruciferous vegetables, produces anti-tumour effect against various tumour cell lines. In this study we characterized LTr1 as a novel anti-glioma agent. Based on screening 134 natural compounds and comparing the candidates' efficacy and toxicity, LTr1 was selected as the lead compound. We showed that LTr1 potently inhibited the viability of human glioma cell lines (SHG-44, U87, and U251) with IC50 values of 1.97, 1.84, and 2.03 µM, respectively. Furthermore, administration of LTr1 (100,300 mg· kg-1 ·d-1, i.g. for 18 days) dose-dependently suppressed the tumour growth in a U87 xenograft nude mouse model. We demonstrated that LTr1 directly bound with TrkA to inhibit its kinase activity and the downstream PI3K/AKT pathway thus inducing significant S-phase cell cycle arrest and apoptosis in SHG-44 and U87 cells by activating the mitochondrial pathway and inducing the production of reactive oxygen species (ROS). Importantly, LTr1 could cross the blood-brain barrier to achieve the therapeutic concentration in the brain. Taken together, LTr1 is a safe and promising therapeutic agent against glioma through inhibiting TrkA/PI3K/AKT pathway.


Assuntos
Glioma , Proteínas Proto-Oncogênicas c-akt , Animais , Humanos , Camundongos , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Glioma/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Proteína Tirosina Quinases , Verduras/metabolismo
7.
Front Microbiol ; 13: 1003714, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36274725

RESUMO

The incidence of infections caused by the H7N9 subtype of the influenza virus has expanded rapidly in China in recent decades, generating massive economic loss and posing a significant threat to public health. In the absence of specialized antiviral treatments or long-term effective preventative vaccinations, it is critical to constantly enhance vaccines and create effective antiviral drugs to prevent the recurrence of pandemics. In the present study, a transmembrane-substituted (TM) virus-like particle (VLP)-based vaccine was created by replacing the transmembrane region of hemagglutinin (HA) protein with the transmembrane region of the H3 HA protein and then used to immunize BALB/c mice. Sera and T cells were collected from the immunized mice to evaluate the passive immune effects. Our results showed that naïve mice achieved 80-100% protection against homologous and heterologous H7N9 influenza strains after receiving passive serum immunization; the protective effect of the TM VLPs was more evident than that of the wild-type HA VLPs. In contrast, mice immunized with passive T cells achieved only 20 to 80% protection against homologous or heterologous strains. Our findings significantly contribute to understanding the control of the H7N9 virus and the development of a vaccine.

8.
Front Cell Infect Microbiol ; 12: 927840, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35873172

RESUMO

Mycoplasma hyopneumoniae is a highly contagious pathogen causing porcine enzootic pneumonia, which elicits prolonged inflammatory response modulated by pattern recognition receptors (PRRs). Although significant advances have been achieved in understanding the Toll-Like receptors that recognize M. hyopneumoniae, the role of nucleotide-binding oligomerization domain 1 (NOD1) in M. hyopneumoniae infected cells remains poorly understood. This study revealed that M. hyopneumoniae activates the NOD1-RIP2 pathway and is co-localized with host NOD1 during infection. siRNA knockdown of NOD1 significantly impaired the TRIF and MYD88 pathway and blocked the activation of TNF-α. In contrast, NOD1 overexpression significantly suppressed M. hyopneumoniae proliferation. Furthermore, we for the first time investigated the interaction between M. hyopneumoniae mhp390 and NOD1 receptor, and the results suggested that mhp390 and NOD1 are possibly involved in the recognition of M. hyopneumoniae. These findings may improve our understanding of the interaction between PRRs and M. hyopneumoniae and the function of NOD1 in host defense against M. hyopneumoniae infection.


Assuntos
Infecções por Mycoplasma , Mycoplasma hyopneumoniae , Pneumonia Suína Micoplasmática , Animais , Inflamação , Mycoplasma hyopneumoniae/genética , Transdução de Sinais , Suínos
9.
Int J Mol Sci ; 23(11)2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35682919

RESUMO

Sugarcane (Saccharum officinarum L.) is one of the world's highly significant commercial crops. The amounts of synthetic nitrogen (N2) fertilizer required to grow the sugarcane plant at its initial growth stages are higher, which increases the production costs and adverse environmental consequences globally. To combat this issue, sustainable environmental and economic concerns among researchers are necessary. The endophytic diazotrophs can offer significant amounts of nitrogen to crops through the biological nitrogen fixation mediated nif gene. The nifH gene is the most extensively utilized molecular marker in nature for studying N2 fixing microbiomes. The present research intended to determine the existence of novel endophytic diazotrophs through culturable and unculturable bacterial communities (EDBCs). The EDBCs of different tissues (root, stem, and leaf) of five sugarcane cultivars (Saccharum officinarum L. cv. Badila, S. barberi Jesw.cv Pansahi, S. robustum, S. spontaneum, and S. sinense Roxb.cv Uba) were isolated and molecularly characterized to evaluate N2 fixation ability. The diversity of EDBCs was observed based on nifH gene Illumina MiSeq sequencing and a culturable approach. In this study, 319766 operational taxonomic units (OTUs) were identified from 15 samples. The minimum number of OTUs was recorded in leaf tissues of S. robustum and maximum reads in root tissues of S. spontaneum. These data were assessed to ascertain the structure, diversity, abundance, and relationship between the microbial community. A total of 40 bacterial families with 58 genera were detected in different sugarcane species. Bacterial communities exhibited substantially different alpha and beta diversity. In total, 16 out of 20 genera showed potent N2-fixation in sugarcane and other crops. According to principal component analysis (PCA) and hierarchical clustering (Bray-Curtis dis) evaluation of OTUs, bacterial microbiomes associated with root tissues differed significantly from stem and leaf tissues of sugarcane. Significant differences often were observed in EDBCs among the sugarcane tissues. We tracked and validated the plethora of individual phylum strains and assessed their nitrogenase activity with a culture-dependent technique. The current work illustrated the significant and novel results of many uncharted endophytic microbial communities in different tissues of sugarcane species, which provides an experimental system to evaluate the biological nitrogen fixation (BNF) mechanism in sugarcane. The novel endophytic microbial communities with N2-fixation ability play a remarkable and promising role in sustainable agriculture production.


Assuntos
Microbiota , Saccharum , Bactérias/genética , Humanos , Nitrogênio , Fixação de Nitrogênio , Saccharum/genética
10.
Gels ; 8(5)2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35621601

RESUMO

Aerogels are three-dimensional nanoporous materials with outstanding properties, especially great thermal insulation. Nevertheless, their extremely high brittleness restricts their practical application. Recently, although the mechanical properties of silica aerogels have been improved by regulating the precursor or introducing a polymer reinforcer, these preparation processes are usually tedious and time-consuming. The purpose of this study was to simplify the preparation process of these composite aerogels. A silicic acid solution treated with cation exchange resin was mixed with agarose (AG) to gel in situ, and then composite aerogels (CAs) with an interpenetrating network (IPN) structure were obtained by aging and supercritical CO2 fluid (SCF) drying. Compared to previous works, the presented CAs preparation process is briefer and more environmentally friendly. Moreover, the CAs exhibit a high specific surface area (420.5 m2/g), low thermal conductivity (28.9 mW m-1 K-1), excellent thermal insulation properties, and thermal stability. These results show that these CAs can be better used in thermal insulation.

11.
Gels ; 8(3)2022 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-35323278

RESUMO

Advanced SiO2-Al2O3 aerogel materials have outstanding potential in the field of thermal insulation. Nevertheless, the creation of a mechanically robust and low-cost SiO2-Al2O3 aerogel material remains a considerable challenge. In this study, SiO2-Al2O3 aerogel based on coal gangue, which is a type of zero-cost inorganic waste, was constructed in porous agarose aerogel beads, followed by simple chemical vapor deposition of trimethylchlorosilane to fabricate SiO2-Al2O3/agarose composite aerogel beads (SCABs). The resulting SCABs exhibited a unique nanoscale interpenetrating network structure, which is lightweight and has high specific surface area (538.3 m2/g), hydrophobicity (approximately 128°), and excellent thermal stability and thermal insulation performance. Moreover, the compressive strength of the SCABs was dramatically increased by approximately a factor of ten compared to that of native SiO2-Al2O3 aerogel beads. The prepared SCABs not only pave the way for the design of a novel aerogel material for use in thermal insulation without requiring expensive raw materials, but also provide an effective way to comprehensively use coal gangue.

12.
Chem Pharm Bull (Tokyo) ; 70(3): 202-210, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35228384

RESUMO

Long-term and constant-release osmotic-pump lorcaserin hydrochloride controlled-release tablets (OP LH CRTs) were prepared, to investigate the influencing factors of LH release and optimize the formulation. The mechanism of release of LH from OP LH CRTs in vitro was investigated. By establishing a high-efficiency method for measuring LH release in vitro, and optimizing it by single-factor and orthogonal experiments, the best formulation of OP LH CRTs was determined. Then, the optimal prescription of OP LH CRTs was: LH = 20.8 mg; mannitol = 100 mg, microcrystalline cellulose = 125 mg; magnesium stearate = 5 mg; cellulose acetate = 3%; polyethylene glycol 400 = 10%; dibutyl phthalate = 10%; Wetting agent and binder was 3% polyvinyl pyrrolidone (PVP) K30 ethanol solution; aperture diameter = 0.8 mm; the coating gained 3% weight. And finally, prepared OP LH CRTs were released at a constant rate in vitro and sustained for 16 h with good reproducibility between batches. Using an orthogonal experimental design, OP LH CRTs with remarkable zero-order release characteristics within 16 h were obtained, and formulation optimization was realized.


Assuntos
Preparações de Ação Retardada , Benzazepinas , Preparações de Ação Retardada/química , Reprodutibilidade dos Testes , Solubilidade , Comprimidos
13.
Gels ; 7(3)2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34563031

RESUMO

Aerogels are nanoporous materials with excellent properties, especially super thermal insulation. However, owing to their serious high brittleness, the macroscopic forms of aerogels are not sufficiently rich for the application in some fields, such as thermal insulation clothing fabric. Recently, freeze spinning and wet spinning have been attempted for the synthesis of aerogel fibers. In this study, robust fibrous silica-bacterial cellulose (BC) composite aerogels with high performance were synthesized in a novel way. Silica sol was diffused into a fiber-like matrix, which was obtained by cutting the BC hydrogel and followed by secondary shaping to form a composite wet gel fiber with a nanoscale interpenetrating network structure. The tensile strength of the resulting aerogel fibers reached up to 5.4 MPa because the quantity of BC nanofibers in the unit volume of the matrix was improved significantly by the secondary shaping process. In addition, the composite aerogel fibers had a high specific area (up to 606.9 m2/g), low density (less than 0.164 g/cm3), and outstanding hydrophobicity. Most notably, they exhibited excellent thermal insulation performance in high-temperature (210 °C) or low-temperature (-72 °C) environments. Moreover, the thermal stability of CAFs (decomposition temperature was about 330 °C) was higher than that of natural polymer fiber. A novel method was proposed herein to prepare aerogel fibers with excellent performance to meet the requirements of wearable applications.

14.
Medicine (Baltimore) ; 100(48): e28103, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-35049238

RESUMO

RATIONALE: Most self-insertion of urethral foreign bodies is the result of exotic impulses, psychometric problems, sexual curiosity, or sexual practice while intoxicated. Ultrasound has been proven to be an effective tool for determining the presence, location, and characteristics of the urethral foreign body. PATIENT CONCERNS: A 48-year-old man presented with a mass in the urethra for 2 years. Physical examination suggested swelling and ulcer in the scrotum. The white blood cell count was elevated (12.60 × 109/L). Urinalysis showed an increased white cell count (484.60/µL) and urine occult blood (±). DIAGNOSIS: Ultrasound examination of the genitourinary system identified an 8.3 cm linear hyperechoic object and hyperechoic spots in the urethra. Computed tomography revealed an extremely hyperdense lesion in the penis. Intraoperative findings showed electric wire bending and winding surrounded by fibrous tissues with urethral rupture. INTERVENTIONS: The patient was treated with urethrotomy as the endoscopic treatment failed. and the electric wire was removed successfully. OUTCOMES: The patient was followed up for 45 days without discomfort. Ultrasound examination of the genitourinary system suggested that the wound was almost healed, but with a small urethral effusion, with a maximum depth of approximately 1.9 mm. LESSONS: A foreign body was inserted into the patient's urethra for 2 years without any medical treatment. Urethral perforation was found during surgery. In such cases, ultrasound examination can determine the location, shape, and size of the urethral foreign body and play an important role in the diagnosis of foreign bodies.


Assuntos
Corpos Estranhos/cirurgia , Pênis/diagnóstico por imagem , Ultrassonografia/métodos , Uretra/diagnóstico por imagem , Endoscopia , Corpos Estranhos/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Uretra/cirurgia
15.
Gels ; 8(1)2021 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-35049552

RESUMO

Forming fibers for fabric insulation is difficult using aerogels, which have excellent thermal insulation performance but poor mechanical properties. A previous study proposed a novel method that could effectively improve the mechanical properties of aerogels and make them into fibers for use in fabric insulation. In this study, composite aerogel fibers (CAFs) with excellent mechanical properties and thermal insulation performance were prepared using a streamlined method. The wet bacterial cellulose (BC) matrix without freeze-drying directly was immersed in an inorganic precursor (silicate) solution, followed by initiating in situ sol-gel reaction under the action of acidic catalyst after secondary shaping. Finally, after surface modification and ambient drying of the wet composite gel, CAFs were obtained. The CAFs prepared by the simplified method still had favorable mechanical properties (tensile strength of 4.5 MPa) and excellent thermal insulation properties under extreme conditions (220 °C and -60 °C). In particular, compared with previous work, the presented CAFs preparation process is simpler and more environmentally friendly. In addition, the experimental costs were reduced. Furthermore, the obtained CAFs had high specific surface area (671.3 m²/g), excellent hydrophobicity, and low density (≤0.154 g/cm3). This streamlined method was proposed to prepare aerogel fibers with excellent performance to meet the requirements of wearable applications.

16.
BMC Plant Biol ; 20(1): 220, 2020 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-32423383

RESUMO

BACKGROUND: Nitrogen is an essential element for sugarcane growth and development and is generally applied in the form of urea often much more than at recommended rates, causing serious soil degradation, particularly soil acidification, as well as groundwater and air pollution. In spite of the importance of nitrogen for plant growth, fewer reports are available to understand the application and biological role of N2 fixing bacteria to improve N2 nutrition in the sugarcane plant. RESULTS: In this study, a total of 350 different bacterial strains were isolated from rhizospheric soil samples of the sugarcane plants. Out of these, 22 isolates were selected based on plant growth promotion traits, biocontrol, and nitrogenase activity. The presence and activity of the nifH gene and the ability of nitrogen-fixation proved that all 22 selected strains have the ability to fix nitrogen. These strains were used to perform 16S rRNA and rpoB genes for their identification. The resulted amplicons were sequenced and phylogenetic analysis was constructed. Among the screened strains for nitrogen fixation, CY5 (Bacillus megaterium) and CA1 (Bacillus mycoides) were the most prominent. These two strains were examined for functional diversity using Biolog phenotyping, which confirmed the consumption of diverse carbon and nitrogen sources and tolerance to low pH and osmotic stress. The inoculated bacterial strains colonized the sugarcane rhizosphere successfully and were mostly located in root and leaf. The expression of the nifH gene in both sugarcane varieties (GT11 and GXB9) inoculated with CY5 and CA1 was confirmed. The gene expression studies showed enhanced expression of genes of various enzymes such as catalase, phenylalanine-ammonia-lyase, superoxide dismutase, chitinase and glucanase in bacterial-inoculated sugarcane plants. CONCLUSION: The results showed that a substantial number of Bacillus isolates have N-fixation and biocontrol property against two sugarcane pathogens Sporisorium scitamineum and Ceratocystis paradoxa. The increased activity of genes controlling free radical metabolism may at least in part accounts for the increased tolerance to pathogens. Nitrogen-fixation was confirmed in sugarcane inoculated with B. megaterium and B. mycoides strains using N-balance and 15N2 isotope dilution in different plant parts of sugarcane. This is the first report of Bacillus mycoides as a nitrogen-fixing rhizobacterium in sugarcane.


Assuntos
Interações entre Hospedeiro e Microrganismos , Microbiota , Fixação de Nitrogênio , Bactérias Fixadoras de Nitrogênio/metabolismo , Saccharum/crescimento & desenvolvimento , Interações Hospedeiro-Patógeno , Bactérias Fixadoras de Nitrogênio/classificação , Bactérias Fixadoras de Nitrogênio/isolamento & purificação , Rizoma/crescimento & desenvolvimento , Rizoma/microbiologia , Saccharum/microbiologia
17.
Neuropharmacology ; 171: 108084, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32294462

RESUMO

In recent years, with the discovery and research of lactate-specific receptor HCAR1(hydroxycarboxylic acid receptor 1), lactate is not only as a product of Glycolysis in astrocytes, but also as a signaling molecule which has gradually received attention. Studies have found that lactate can be used as an intercellular signaling molecule involved in synaptic plasticity, and so that peripheral administration of lactate can produce antidepressant effects. Here, we focus on HCAR1 on the most widely distributed astrocytes in the brain, found and verified that lactate could cause Arc/arg3.1 protein overexpression in astrocytes through HCAR1. However, the expression of Arc/arg3.1 does not depend on the Gi protein pathway of HCAR1, and we found that lactate enhanced the expression of Arc/arg3.1 protein through the HCAR1-ß-arrestin2 pathway. In summary, lactate acts on HCAR1 of astrocytes. It enhances the expression of MAPK-dependent Arc through ß-arrestin2, thereby reducing the influx of calcium ions when astrocytes are exposed to glutamate damage, achieving the role of protecting astrocytes and indirectly enhancing the absorption of glutamate by astrocytes. These results also demonstrate that HCAR1 in the brain is a potential therapeutic target in an experimental in vitro model of glutamate damage, which is strongly associated with many neurodegenerative diseases.


Assuntos
Astrócitos/efeitos dos fármacos , Proteínas do Citoesqueleto/efeitos dos fármacos , Ácido Láctico/farmacologia , Proteínas do Tecido Nervoso/efeitos dos fármacos , Receptores Acoplados a Proteínas G/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , beta-Arrestina 2/efeitos dos fármacos , Animais , Sinalização do Cálcio/efeitos dos fármacos , Células Cultivadas , Proteínas do Citoesqueleto/biossíntese , Potenciação de Longa Duração/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Proteínas do Tecido Nervoso/biossíntese , Doenças Neurodegenerativas/tratamento farmacológico , Plasticidade Neuronal/efeitos dos fármacos , Receptores Acoplados a Proteínas G/biossíntese
18.
Methods Mol Biol ; 2057: 103-112, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31595474

RESUMO

Nitrogen (N2) is the most necessary element in the atmosphere, it is an energetic micronutrient for plant growth and development after water, besides its key role in chlorophyll production, which is crucial for photosynthesis process. Biological nitrogen fixation is measured to be the most potent method to deliver a fixed way of nitrogen to the plants. Plant depends on free-living and symbiotic microbes present in the soil for nitrogen because it cannot be absorbed by the plant itself directly from the atmosphere. Many techniques were reported in the laboratory for nitrogen estimation till now, but Kjeldahl digestion and acetylene reduction assay (ARA) techniques became the most popular. In this chapter, we focus on the most common and popular methods used to determine plant N2; awareness obtained through the wide application of these methods should offer the source for the N2 fixation rate in agriculture system.


Assuntos
Bactérias/química , Nitrogênio/análise , Plantas/química , Acetileno/química , Bactérias/metabolismo , Botânica/métodos , Espectrometria de Massas , Técnicas Microbiológicas/métodos , Nitrogênio/metabolismo , Fixação de Nitrogênio , Simbiose , Fluxo de Trabalho
19.
Neuropharmacology ; 160: 107779, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31539536

RESUMO

Depression is considered a neuropsychiatric condition which is associated with neuronal injury within specific brain regions. We previously reported that cyclo-oxygenase (COX)-2, a rate-limiting enzyme for prostaglandin E2 (PGE2) synthesis, significantly enhanced depressive-like disorders induced by chronic stress in rats. However, the underlying molecular mechanisms and identification of potential therapeutic targets for preventing neuronal injury associated with depression remain largely uncharacterized. Here, we show that COX-2 inhibition by celecoxib protects against neuronal injury through suppression of oxidative stress and, in this way, mediates its antidepressant effects. COX-2 is highly expressed in the hippocampal dentate gyrus (DG) of rat depression model and its activity is responsible for depression-like behaviors as demonstrated in two independent rat models of depression. Inhibition of COX-2 exerts neuroprotective actions in DG regions, including suppressing neuroinflammatory response, against oxidative stress and neuronal apoptosis, which are the critical risk factors for neuronal injury and pathophysiology of depression. Moreover, the antioxidant, N-acetylcysteine (NAC), significantly attenuates oxidative stress levels and dendritic spine deficiencies resulting from COX-2 overexpression; and, suppression of oxidative stress by NAC also significantly ameliorates depressive behaviors in rats. These findings suggest that selective inhibition of COX-2 ameliorates depression-like behaviors in rat models of depression. This selective inhibition of COX-2 appears to be protective against oxidative stress and neuronal deterioration resulting from chronic stress. Taken together, these findings have potentially important clinical implications with regard to the development of novel therapeutic approaches in the treatment of neuropsychiatric conditions like depression.


Assuntos
Apoptose/efeitos dos fármacos , Celecoxib/farmacocinética , Inibidores de Ciclo-Oxigenase 2/farmacologia , Depressão/tratamento farmacológico , Neurônios/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Antidepressivos/administração & dosagem , Antidepressivos/farmacologia , Celecoxib/administração & dosagem , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/administração & dosagem , Depressão/fisiopatologia , Modelos Animais de Doenças , Inflamação/tratamento farmacológico , Masculino , Neuroglia/efeitos dos fármacos , Ratos , Ratos Wistar , Estresse Psicológico
20.
Brain Behav Immun ; 82: 106-121, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31394209

RESUMO

Neuronal injury within specific brain regions is considered a critical risk factor in the pathophysiology of depression. However, the underlying mechanisms of this process, and thus the potential for development of novel therapeutic strategies in the treatment of depression, remain largely unknown. Here, we report that Il-6 protects against neuronal anomalies related with depression, in part, by suppressing oxidative stress and consequent autophagic and apoptotic hyperactivity. Specifically, we show that IL-6 is downregulated within the CA1 hippocampus in two animal models of depression and upregulated by antidepressants. Increasing levels of IL-6 in the CA1 region result in pleiotropic protective actions including reductions in oxidative stress and modulation of autophagy, anti-immuno-inflammatory activation and anti-apoptotic effects in CA1 neurons, all of which are associated with the rescue of depression-like behaviors. In contrast, IL-6 downregulation exacerbates neuronal anomalies within the CA1 region and facilitates the genesis of depression phenotypes in rats. Interestingly, in addition to attenuating oxidative damage, the antioxidant, N-acetylcysteine (NAC), is also associated with significantly decreased neuronal deficits and the display of depressive behaviors in rats. These results suggest that IL-6 may exert neuroprotection within CA1 neurons via pleiotropic mechanisms and may serve as a potential therapeutic target for the treatment of depression.


Assuntos
Depressão/metabolismo , Interleucina-6/metabolismo , Animais , Antidepressivos/uso terapêutico , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Região CA1 Hipocampal/metabolismo , Região CA1 Hipocampal/fisiologia , Depressão/imunologia , Depressão/fisiopatologia , Transtorno Depressivo/tratamento farmacológico , Transtorno Depressivo/metabolismo , Modelos Animais de Doenças , Hipocampo/metabolismo , Interleucina-6/farmacologia , Masculino , Neurônios/efeitos dos fármacos , Neuroproteção , Estresse Oxidativo/fisiologia , Ratos , Ratos Wistar , Estresse Psicológico/fisiopatologia
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