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1.
PLoS One ; 19(4): e0301296, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38574046

RESUMEN

In this study, the complex interactions between soil types, compaction, and moisture on nitrogen (N) transformation processes such as ammonia (NH3) volatilization, ammonification, nitrification, and denitrification were examined over a 30-day period using a simulated column approach. Two soil types: loam, and sandy loam, were subjected to three compaction treatments-control, surface, and sub-surface compaction-and two moisture regimes, dry and wet. Liquid urea ammonium nitrate (32-0-0) was used as the N fertilizer source at a rate of 200 kg N ha-1. Key indicators of N transformations were measured, including residual concentrations of ammonium (NH4-N) and nitrate (NO3-N), NO3-N leaching, NH3 volatilization, and nitrous oxide (N2O) emissions. Findings revealed that compaction significantly increased residual NH4-N concentrations in deeper soil profiles, with the highest 190.80 mg kg-1 recorded in loam soil under sub-surface compaction and dry conditions. Nitrification rates decreased across both soil types due to compaction, evidenced by elevated residual NH4-N levels. Increased NO3-N leaching was observed in loam soil (178.06 mg L-1), greater than sandy loam (81.11 mg L-1), due to initial higher residual NO3- in loam soil. The interaction of compaction and moisture most affected N2O emissions, with the highest emissions in control treatments during dry weather at 2.88 kg ha -1. Additionally, higher NH3 volatilization was noted in moist sandy loam soil under control conditions at 19.64 kg ha -1. These results highlight the necessity of considering soil texture, moisture, and compaction in implementing sustainable N management strategies in agriculture and suggest recommendations such as avoiding broadcast application in moist sandy loam and loam soil to mitigate NH3 volatilization and enhance N use efficiency, as well as advocating for readjustment of fertilizer rate based on organic matter content to reduce potential NO3-N leaching and N2O emissions, particularly in loam soil.


Asunto(s)
Nitrógeno , Suelo , Fertilizantes/análisis , Agricultura , Amoníaco/análisis , Arena , Óxido Nitroso/análisis
2.
Cureus ; 15(10): e46663, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37942368

RESUMEN

BACKGROUND: Allergic rhinitis is largely treated by using antihistamines and nasal sprays, either alone or in combination. However, these measures ease out the symptoms but do not address causative factors, and have their share of side effects and limitations. An Ayurvedic herbo-mineral formulation, IMMBO, has been reported to be effective in treating allergic rhinitis. OBJECTIVE: The present study was carried out to evaluate the efficacy, safety, and tolerability of the Ayurvedic herbo-mineral formulation in comparison with a fixed-dose combination of levocetirizine and montelukast. METHOD: This was a randomized, comparative, clinical study carried out on 250 patients at a medical college in India. The patients were enrolled according to the eligibility criteria of the study and randomized into two groups, to receive either Ayurvedic herbo-mineral formulation, IMMBO, or a combination of levocetirizine and montelukast for 28 days. Total nasal symptom score (TNSS) and Immunoglobulin E (IgE) were calculated for evaluation of efficacy parameters.  Result: At the end of therapy both IMMBO and levocetirizine and montelukast combination showed significant improvement in TNSS in both treated population and per protocol population. The IMMBO group had a statistically higher reduction in TNSSs compared to the levocetirizine + montelukast group (-5.70 vs. -3.31; p<0.01). There was a statistically significant difference in the reduction of IgE levels between the groups (-351.54 vs. -208.79; p<0.05).  Conclusion: The findings of this study establish prima facie evidence about the efficacy and safety of Ayurvedic formulation. However, the said Ayurvedic formulation needs to be further developed scientifically.

3.
Plant Commun ; 4(6): 100726, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37789617

RESUMEN

Rapid climate change has led to enhanced soil salinity, one of the major determinants of land degradation, resulting in low agricultural productivity. This has a strong negative impact on food security and environmental sustainability. Plants display various physiological, developmental, and cellular responses to deal with salt stress. Recent studies have highlighted the root cap as the primary stress sensor and revealed its crucial role in halotropism. The root cap covers the primary root meristem and is the first cell type to sense and respond to soil salinity, relaying the signal to neighboring cell types. However, it remains unclear how root-cap cells perceive salt stress and contribute to the salt-stress response. Here, we performed a root-cap cell-specific proteomics study to identify changes in the proteome caused by salt stress. The study revealed a very specific salt-stress response pattern in root-cap cells compared with non-root-cap cells and identified several novel proteins unique to the root cap. Root-cap-specific protein-protein interaction (PPI) networks derived by superimposing proteomics data onto known global PPI networks revealed that the endoplasmic reticulum (ER) stress pathway is specifically activated in root-cap cells upon salt stress. Importantly, we identified root-cap-specific jacalin-associated lectins (JALs) expressed in response to salt stress. A JAL10-GFP fusion protein was shown to be localized to the ER. Analysis of jal10 mutants indicated a role for JAL10 in regulating the ER stress pathway in response to salt. Taken together, our findings highlight the participation of specific root-cap proteins in salt-stress response pathways. Furthermore, root-cap-specific JAL proteins and their role in the salt-mediated ER stress pathway open a new avenue for exploring tolerance mechanisms and devising better strategies to increase plant salinity tolerance and enhance agricultural productivity.


Asunto(s)
Proteínas de Plantas , Proteoma , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Lectinas , Estrés del Retículo Endoplásmico , Plantas/metabolismo , Suelo
4.
BMC Plant Biol ; 23(1): 493, 2023 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-37833626

RESUMEN

BACKGROUND: Reproductive stage drought stress (RDS) is a major global threat to rice production. Due to climate change, water scarcity is becoming an increasingly common phenomenon in major rice-growing areas worldwide. Understanding RDS mechanisms will allow candidate gene identification to generate novel rice genotypes tolerant to RDS. RESULTS: To generate novel rice genotypes that can sustain yield under RDS, we performed gamma-irradiation mediated mutation breeding in the drought stress susceptible mega rice variety, MTU1010. One of the mutant MM11 (MTU1010 derived mutant11) shows consistently increased performance in yield-related traits under field conditions consecutively for four generations. In addition, compared to MTU1010, the yield of MM11 is sustained in prolonged drought imposed during the reproductive stage under field and in pot culture conditions. A comparative emerged panicle transcriptome analysis of the MTU1010 and MM11 suggested metabolic adjustment, enhanced photosynthetic ability, and hormone interplay in regulating yield under drought responses during emerged panicle development. Regulatory network analysis revealed few putative significant transcription factor (TF)-target interactions involved in integrated signalling between panicle development, yield and drought stress. CONCLUSIONS: A gamma-irradiate rice mutant MM11 was identified by mutation breeding, and it showed higher potential to sustain yield under reproductive stage drought stress in field and pot culture conditions. Further, a comparative panicle transcriptome revealed significant biological processes and molecular regulators involved in emerged panicle development, yield and drought stress integration. The study extends our understanding of the physiological mechanisms and candidate genes involved in sustaining yield under drought stress.


Asunto(s)
Oryza , Transcriptoma , Oryza/metabolismo , Sequías , Fitomejoramiento , Genes Reguladores , Estrés Fisiológico/genética
5.
Plant Cell Physiol ; 63(8): 1038-1051, 2022 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-35662353

RESUMEN

Land plants have developed robust roots to grow in diverse soil ecosystems. The distal end of the root tip has a specialized organ called the 'root cap'. The root cap assists the roots in penetrating the ground, absorbing water and minerals, avoiding heavy metals and regulating the rhizosphere microbiota. Furthermore, root-cap-derived auxin governs the lateral root patterning and directs root growth under varying soil conditions. The root cap formation is hypothesized as one of the key innovations during root evolution. Morphologically diversified root caps in early land plant lineage and later in angiosperms aid in improving the adaptation of roots and, thereby, plants in diverse soil environments. This review article presents a retrospective view of the root cap's important morphological and physiological characteristics for the root-soil interaction and their response toward various abiotic and biotic stimuli. Recent single-cell RNAseq data shed light on root cap cell-type-enriched genes. We compiled root cap cell-type-enriched genes from Arabidopsis, rice, maize and tomato and analyzed their transcription factor (TF) binding site enrichment. Further, the putative gene regulatory networks derived from root-cap-enriched genes and their TF regulators highlight the species-specific biological functions of root cap genes across the four plant species.


Asunto(s)
Arabidopsis , Suelo , Arabidopsis/genética , Ecosistema , Ácidos Indolacéticos/metabolismo , Raíces de Plantas/metabolismo , Estudios Retrospectivos
6.
IEEE Trans Biomed Eng ; 67(1): 226-233, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-30998454

RESUMEN

In the last several years, conventional drug delivery systems (DDS) have evolved into DDS that are responsive to exogenous or endogenous stimuli. The objective of this paper is to present a DDS that is responsive to an electric stimulus in the form of bipolar electric pulses. The DDS structure is based on chitosan embedded with magnetic nanoparticles, and crosslinked with polyethylene glycol dimethacrylate to form microbeads. This DDS is loaded with vancomycin as the therapeutic agent of interest. Silver inter-digitated electrodes (IDE) were printed on polyimide substrates with a MEMS-based inkjet material deposition printer, and used to provide 100 Hz pulses of electric current to the DDS for 3 min. The results showed that the stimulated groups released ∼800% more vancomycin than the non-stimulated groups in the excitation duration, but followed a first-order elution profile otherwise. Another significance of our approach is that it does not need complicated or expensive fabrication processes, and can be customized according to the targeted implant site. The IDE system has also been modeled using COMSOL to study the distributed electric fields and ion migration during the stimulus. This paper demonstrates a novel and promising technique of providing stimulus to drug substrates for controllable drug delivery.


Asunto(s)
Quitosano/química , Sistemas de Liberación de Medicamentos/métodos , Nanopartículas de Magnetita/química , Electricidad , Diseño de Equipo , Microelectrodos , Microesferas , Vancomicina/farmacocinética
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2018: 4277-4280, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30441299

RESUMEN

Inkjet printing (IJP) is an exciting new additive manufacturing technology that promises monolithic electronic circuit fabrication of $\mu \mathrm{m}$ thin low-cost large-area electronic low-cost body-worn flexible sensors. In this work, we demonstrate inkjet printed multilayer metal-dielectric-metal capacitors on flexible polyimide (PI) substrate by formulating a custom dielectric ink based on Poly 4-vinylphenol (PVP). Silver nanoparticle ink was used for printing theconductive parallel metal plates. We also demonstrate control over the capacitance values by varying the design parameters and succeeded in printing capacitors in the range 8.8 pF to 467 pF, with excellent repeatability on flexible PI substrates. A functional LC circuit using these printed capacitors has been designed and demonstrated to have a resonance frequency of 24.3 MHz. These results are a vital step forward towards monolithic printing of flexible electronic circuits using IJP technique formany applications such as body-worn sensors.


Asunto(s)
Nanopartículas del Metal , Polivinilos/química , Pirrolidinas/química , Tinta , Impresión , Impresión Tridimensional , Plata
8.
J Biomed Mater Res B Appl Biomater ; 106(6): 2169-2176, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29052337

RESUMEN

Local antibiotic delivery can overcome some of the shortcomings of systemic therapy, such as low local concentrations and delivery to avascular sites. A localized drug delivery system (DDS), ideally, could also use external stimuli to modulate the normal drug release profile from the DDS to provide efficacious drug administration and flexibility to healthcare providers. To achieve this objective, chitosan microbeads embedded with magnetic nanoparticles were loaded with the antibiotic vancomycin and stimulated by a high frequency alternating magnetic field. Three such stimulation sessions separated by 1.5 h were applied to each test sample. The chromatographic analysis of the supernatant from these stimulated samples showed more than approximately 200% higher release of vancomycin from the DDS after the stimulation periods compared to nonstimulated samples. A 16-day long term elution study was also conducted where the DDS was allowed to elute drug through normal diffusion over a period of 11 days and stimulated on day 12 and day 15, when vancomycin level had dropped below therapeutic levels. Magnetic stimulation boosted elution of test groups above minimum inhibitory concentration (MIC), as compared to control groups (with no stimulation) which remained below MIC. The drug release from test groups in the intervals where no stimulation was given showed similar elution behavior to control groups. These results indicate promising possibilities of controlled drug release using magnetic excitation from a biopolymer-based DDS. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2169-2176, 2018.


Asunto(s)
Quitosano/química , Campos Magnéticos , Nanopartículas de Magnetita/química , Microesferas , Vancomicina , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacocinética , Vancomicina/química , Vancomicina/farmacocinética
9.
Int J Biol Macromol ; 104(Pt B): 1407-1414, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28365285

RESUMEN

Stimuli-responsive biomaterials offer a unique advantage over traditional local drug delivery systems in that the drug elution rate can be controllably increased to combat developing symptomology or maintain high local elution levels for disease treatment. In this study, superparamagnetic Fe3O4 nanoparticles and the antibiotic vancomycin were loaded into chitosan microbeads cross-linked with varying lengths of polyethylene glycol dimethacrylate. Beads were characterized using degradation, biocompatibility, and elution studies with successive magnetic stimulations at multiple field strengths and frequencies. Thirty-minute magnetic stimulation induced a temporary increase in daily elution rate of up to 45% that was dependent on field strength, field frequency and cross-linker length. Beads degraded by up to 70% after 3 days in accelerated lysozyme degradation tests, but continued to elute antibiotic for up to 8 days. No cytotoxic effects were observed in vitro compared to controls. These promising preliminary results indicate clinical potential for use in stimuli-controlled drug delivery.


Asunto(s)
Quitosano/química , Portadores de Fármacos/química , Liberación de Fármacos , Campos Magnéticos , Animales , Quitosano/farmacología , Portadores de Fármacos/farmacología , Nanopartículas de Magnetita/química , Ensayo de Materiales , Ratones , Células 3T3 NIH , Vancomicina/química
10.
Crit Rev Biomed Eng ; 43(5-6): 347-69, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-27480580

RESUMEN

In generic terms, a drug delivery substrate (DDS) can be described as a vehicle to transport drug to the point of interest. A DDS that would ideally have the capability to control drug dosage and achieve target specificity, localization, and higher therapeutic efficacy has been pursued as a holy grail in pharmaceutical research. Over the years, diverse classes, structures, and modifications of DDS have been proposed to achieve this aim. One of its major deterrents, however, is rapid elimination of drug by the immune system before intended functionality. Stealth engineering is broadly defined as a method of designing a drug carrier to minimize or delay opsonization until the encapsulated drug is delivered to the intended target. Stealth-engineered DDS has been successful in extending drug circulation lifetime from a few minutes to several days. Currently, this field of research has made much progress since its initiation in 1960s with liposomes to DNA boxes. Activity has also benefited several areas of medicine, where it has been applied in cancer, gene therapy, bone regrowth, and infection treatment. This review covers the progress of some types of DDS that have been published and indexed in major databases (including ScienceDirect, PubMed, and Google Scholar) in the scientific literature.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Vehículos Farmacéuticos , ADN , Terapia Genética/métodos , Humanos , Infecciones/tratamiento farmacológico , Liposomas , Neoplasias/tratamiento farmacológico , Osteogénesis , Vehículos Farmacéuticos/administración & dosificación , Vehículos Farmacéuticos/farmacocinética
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