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1.
Rev Sci Instrum ; 95(5)2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38717270

RESUMEN

An efficient and compact, 20 kW solid-state power amplifier (SSA) at 325 MHz has been designed and developed in-house, using single stage combining. It comprises of 24 nos. of 1 kW power amplifier (PA) modules, a 24-way Wilkinson power combiner and divider, and other peripheral systems. The typical gain and conversion efficiency of the PA modules at 1.0 kW output is 21.7 dB and 66.6%, respectively. It is demonstrated that overall power gain and AC to RF efficiency of this SSA at 20 kW is 88.5 dB and 54.8%, respectively, which matches closely with the design estimates. The harmonic content in the RF output is < -40 dBc for all the harmonics. The results of the Monte Carlo simulation are also presented, showing lower bound on combining efficiency with a degree of confidence if magnitude and phase data for 24 inputs are randomly chosen from a normal distribution's pre-defined interval. The salient features of this SSA include power density of 12.7 kW/m3, AC to RF efficiency of 54.8% at 20 kW, and guaranteed output of 20 kW with one failed PA module and 18.1 kW under two failed PA modules condition.

2.
J Basic Microbiol ; 64(6): e2300767, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38616707

RESUMEN

In the current study salt tolerant-plant growth-promoting rhizobacteria (ST-PGPR) Pseudomonas atacamensis KSS-6, selected on the basis of prominent plant growth-promoting (PGP) and stress tolerance properties was tested as bioinoculant to improve yield of rice grown in saline soil. The ST-PGPR KSS-6 was capable of maintaining the PGP traits up to 200 mM NaCl, however, higher salt stress conditions affected these activities. The study was designed to determine the effect of developed talc-based bioformulation using KSS-6 along with organic manure (OM) on growth and yield of paddy under saline conditions. Bioformulation broadcasting was also done to examine the effect on soil properties. It was found that the combinatorial treatment showed positive impact on growth and yield of rice under saline conditions. Co-application of KSS-6 with OM showed maximum increment in growth, chlorophyll content, plant fresh weight, and dry weight as compared to untreated control plants. Furthermore, the combinatorial treatment improved the nutrient content (P, K, Zn, Fe, Mg, and Mn) by more than 35% and enhanced the biochemical parameters such as proline, flavonoids, carbohydrates, protein, dietary fiber, and antioxidant content of rice grains by more than 32%. Soil parameters including pH and electrical conductivity (EC), moisture content, total organic carbon, OM, sodium, and chloride ions were also improved upon treatment. There was significant lowering of EC from 7.43 to 4.3 dS/m when combination of OM and bacteria were applied. These findings suggest that the application of KSS-6 in the form of bioinoculant could be a promising strategy to mitigate negative impacts of salt stress and enhance the yield and nutritional properties of rice grown in degraded and saline soil.


Asunto(s)
Estiércol , Oryza , Pseudomonas , Microbiología del Suelo , Suelo , Oryza/crecimiento & desarrollo , Oryza/microbiología , Oryza/metabolismo , Pseudomonas/metabolismo , Pseudomonas/crecimiento & desarrollo , Estiércol/microbiología , Suelo/química , Estrés Salino , Tolerancia a la Sal , Nutrientes/metabolismo , Plantas Tolerantes a la Sal/crecimiento & desarrollo , Plantas Tolerantes a la Sal/microbiología , Clorofila/metabolismo , Salinidad , Cloruro de Sodio/farmacología
3.
World J Microbiol Biotechnol ; 40(1): 11, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37953356

RESUMEN

Salt-tolerant plant growth promoting rhizobacteria (ST-PGPR) are known to ameliorate salt stress in plants by various mechanisms. The current study aims to investigate the role of an ST-PGPR strain Pseudomonas taiwanensis PWR-1 applied along with a reduced dose of mineral fertilizers (N, P, and K) in the improvement of the antioxidant and nutritional properties of wheatgrass (Triticum aestivum L.) grown in saline soil. Application of P. taiwanensis PWR-1 along with 50% of the recommended dose of mineral fertilizers resulted in a significant improvement of growth parameters including shoot length (22.79%), root length (20.38%), fresh weight (13.15%), dry weight (92.34%), vigor index (13.36%), and relative water content (48.24%). The combined application of PWR-1 and mineral fertilizers increased the production of osmoprotectants (proline, total soluble sugars, glycine betaine), antioxidants (SOD, POD, APX, CAT, PPO, and reduced glutathione), and free radical scavengers (DPPH and H2O2) in wheatgrass. Furthermore, the concentration of micronutrients (Zn and Fe), macronutrients (N, and P), and vitamins (B1 and E) also increased in the above treatment. Oxidative stress markers (malondialdehyde and electrolyte leakage) and Na+ accumulation were significantly reduced whilst K+ content increased in the shoot, which helped in maintaining the K+/Na+ ratio in wheatgrass under saline conditions. The results indicated that the application of ST-PGPR could not only reduce the dosage of mineral fertilizers but might be useful for improving the nutritional and antioxidant properties of medicinal crops such as wheatgrass under salt-stress conditions. Implementing this approach could result in the reduction of chemical usage, while also facilitating enhanced uptake of micronutrients in crops, particularly in regions affected by salinity.


Asunto(s)
Antioxidantes , Fertilizantes , Suelo/química , Peróxido de Hidrógeno , Minerales , Micronutrientes
4.
Microbiol Res ; 275: 127442, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37437425

RESUMEN

Trace element deficiency is a pervasive issue contributing to malnutrition on a global scale. The primary cause of this hidden hunger is related to low dietary intake of essential trace elements, which is highly prevalent in numerous regions across the world. To address deficiency diseases in humans, fortification of staple crops with vital trace elements has emerged as a viable solution. Current methods for fortifying crops encompass chemical amendments, genetic breeding, and transgenic approaches, yet these approaches possess certain limitations, constraining their agricultural application. In contrast, fortifying staple crops through the utilization of soil-beneficial microbes has emerged as a promising and economically feasible approach to enhance trace element content in crops. A specific subset of these beneficial soil microbes, referred to as plant growth-promoting microbes, have demonstrated their ability to influence the interactions between plants, soil, and minerals. These microbes facilitate the transport of essential soil minerals, such as zinc, iron, and selenium, into plants, offering the potential for the development of tailored bioinoculants that can enhance the nutritional quality of cereals, pulses, and vegetable crops. Nevertheless, further research efforts are necessary to comprehensively understand the molecular mechanisms underlying the uptake, transport, and augmentation of trace element concentrations in staple crops. By delving deeper into these mechanisms, customized bioinoculants of soil-beneficial microbes can be developed to serve as highly effective strategies in combating trace element deficiency and promoting global nutritional well-being.


Asunto(s)
Selenio , Oligoelementos , Humanos , Biofortificación , Suelo , Zinc , Productos Agrícolas
5.
Int J STD AIDS ; 34(11): 763-776, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37269245

RESUMEN

Background: HIV pre-exposure prophylaxis (PrEP) is part of India's HIV prevention policy. We aimed to determine awareness of and willingness-to-use PrEP among men-who-have-sex-with-men (MSM) and transgender-persons (TG) in Delhi, India.Methods: A cross-sectional study was conducted at five purposively selected targeted-intervention projects in Delhi. Participants included self-identified MSM/TG aged ≥18 years, with negative/unknown HIV serostatus. A structured interview schedule, developed using formative research, was used. Primary outcomes were awareness of, and willingness-to-use PrEP. Socio-demographic and behaviour variables included age, living situation, education, anal-sex, condom-use and experiences of physical-violence. Determinants of outcome were identified in univariable logistic regression; variables associated at p < .25 were included in multivariable regression models.Results: Of 400 (224 MSM, 176 TG), mean ± SD age 25.7 ± 7.2 years, 14.5% (95% CI 11.0, 18.0) were aware of PrEP, while 63.3% (95% CI: 58.6, 68.1) reported willingness-to-use PrEP. PrEP-awareness was independently associated with formal-education (adjusted odds ratio; AOR = 1.20), professional occupation (AOR = 5.45) and condom-use (AOR = 3.07). Willingness-to-use PrEP was higher if participants had recent anal-sex (AOR = 2.29), had used condoms during anal-sex (AOR = 2.09), or recently experienced physical-violence (AOR = 3.65).Conclusions: PrEP awareness was low, but most were willing to use PrEP, implying that communication is key to PrEP awareness and uptake.


Asunto(s)
Infecciones por VIH , Profilaxis Pre-Exposición , Minorías Sexuales y de Género , Personas Transgénero , Masculino , Humanos , Adolescente , Adulto , Adulto Joven , Homosexualidad Masculina , Estudios Transversales , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , India/epidemiología
6.
Appl Opt ; 61(13): 3695-3701, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36256410

RESUMEN

Convolutional neural network based transfer learning (TL) is proposed to achieve joint optical performance monitoring with bit rate and modulation format identification in optical communication systems. TL is used to improve the execution of various tasks by extracting features without knowing other optical link parameters. Eye diagrams of four different modulation formats are generated at optical signal-to-noise ratios (OSNRs) varying from 15 to 30 dB for two distinct bit rates, which are then identified simultaneously with a trained deep neural network. In addition, comparisons of different TL approaches are presented. The database is divided into distinct categories with varying parameter ranges in offline mode, and prediction models are assigned to each class. The results suggest that the proposed system may greatly increase identification performance over existing strategies by utilizing TL techniques. The impacts of training, testing, and validation data size, as well as model structure based on TL, are also thoroughly investigated. The results reveal that the VGG16 achieves the highest accuracies compared to other deep learning algorithms even at low OSNR values of 20 dB. The proposed structure can intelligently evaluate the signals of future heterogeneous optical communications, and the results can be used to enhance optical network management.

7.
3 Biotech ; 12(6): 138, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35646503

RESUMEN

Maize (Zea mays L.) is a major cereal crop grown in a large number of countries. Loss in maize yield due to biotic stresses including fungal phytopathogens is a matter of immense concern. Control measures applied for eradication of fungal phytopathogens in maize are not up to the mark and more often involve harsh chemical(s)/pesticide(s) that cause deleterious effects both in humans and soil biota. Greener alternatives, such as the use of rhizosphere microbes in the form of bioinoculants, have proven to be very successful in terms of enhancing crop yield and suppressing fungal phytopathogens. In the present study, fluorescent pseudomonads were isolated from the maize rhizosphere and monitored for their plant growth-promoting (PGP) and biocontrol activities against Fusarium moniliforme. Based on various PGP traits and biocontrol potential, isolate JM-1 was found to be most effective and as per 16S rRNA gene sequencing analysis was identified as Pseudomonas fluorescens. Further experiments showed that the biocontrol potential of JM-1 against ear rot fungus involved the production of antifungal compound 2,4-diacetylphloroglucinol (DAPG). When examined for antagonistic interaction under scanning electron microscopy (SEM), structural abnormality, hyphal lysis, and deformity in fungal mycelium were observed. In the pot experiment, application of talc-based JM-1 containing bioformulation (in pot trials) showed significant enhancement in maize growth parameters (including the seed number and weight) in comparison to control even in presence of the phytopathogen. Ear fresh weight, dry weight, number of seeds per plant, and 100-grain weight were found to increase significantly by 34, 34, 52, and 18% respectively, in comparison to control. P. fluorescens JM-1 can therefore be used as a bioinoculant for ear rot disease control and sustainably enhancing maize yield. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-022-03201-7.

8.
Microbiol Res ; 252: 126861, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34521049

RESUMEN

Soil salinity has emerged as a great threat to the agricultural ecosystems throughout the globe. Many continents of the globe are affected by salinity and crop productivity is severely affected. Anthropogenic activities leading to the degradation of agricultural land have also accelerated the rate of salinization in arid and semi-arid regions. Several approaches are being evaluated for remediating saline soil and restoring their productivity. Amongst these, utilization of plant growth promoting bacteria (PGPB) has been marked as a promising tool. This greener approach is suitable for simultaneous reclamation of saline soil and improving the productivity. Salt-tolerant PGPB utilize numerous mechanisms that affect physiological, biochemical, and molecular responses in plants to cope with salt stress. These mechanisms include osmotic adjustment by ion homeostasis and osmolyte accumulation, protection from free radicals by the formation of free radicals scavenging enzymes, oxidative stress responses and maintenance of growth parameters by the synthesis of phytohormones and other metabolites. As salt-tolerant PGPB elicit better plant survival under salinity, they are the potential candidates for enhancing agricultural productivity. The present review focuses on the various mechanisms used by PGPB to improve plant health under salinity. Recent developments and prospects to facilitate better understanding on the functioning of PGPB for ameliorating salt stress in plants are emphasized.


Asunto(s)
Fenómenos Fisiológicos Bacterianos , Ecosistema , Interacciones Microbiota-Huesped , Plantas , Estrés Salino , Interacciones Microbiota-Huesped/fisiología , Plantas/microbiología , Suelo/química
9.
Foot (Edinb) ; 48: 101813, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34332396

RESUMEN

Giant cell tumor of tendon sheath usually is localized painless solitary benign swelling, which presents as a firm nodular gradually growing mass. Giant cell tumor is infrequent in the lower limb and its incidence in the tendo Achilles is rare. It is often diagnosed and treated conservatively as tendinitis in the initial stages. The slow growth and limited functional deficit is the reason for its late presentation where excision of the mass leaves a large residual defect, for which reconstruction of the tendo Achilles has to be done by mobilizing different tendons. A case series of bilateral giant cell tumor of tendo Achilles and study the functional outcome of the reconstructed tendo Achilles using peroneus brevis - tibialis posterior tendons - are presented. The outcome of reconstruction using peroneus brevis - tibialis posterior tendon gave satisfactory outcome at the end of one year. LEVEL OF EVIDENCE: Level 4.


Asunto(s)
Tendón Calcáneo , Tumores de Células Gigantes , Tendinopatía , Tendón Calcáneo/cirugía , Pie , Tumores de Células Gigantes/cirugía , Humanos , Músculo Esquelético
10.
Environ Sustain (Singap) ; 4(3): 455-467, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-38624661

RESUMEN

Coronavirus disease (COVID-19) caused by severe acute respiratory syndrome (SARS) coronavirus 2 (SARS-CoV-2) has taken mankind by surprise with various unprecedented impacts on human life around the globe. This zoonotic pandemic is proving to be the most destructive disease outbreaks since decades. The increasing human population and anthropogenic activities have impacted the environment and have direct linkages with the current and other recent outbreaks of zoonotic diseases. Despite having a difference in their origin, major reasons behind the emergence and spread of zoonotic pandemics are related to activities such as habitat fragmentation, deforestation, biodiversity loss, intensive agriculture and livestock farming, uncontrolled urbanization, pollution, climate change and bushmeat hunting and trading. It is important to focus on environmental and climatic factors that are involved in the emergence of such pandemics involving novel human pathogens and viruses in particular. Research and data analysis, particularly in relation to COVID-19, has shown that meteorological factors along with population density and living conditions (particularly in the urban and semi-urban areas) play a crucial role in the intensity, evolution and spread of SARS-CoV-2. This particular virus is novel but coronaviruses have a long history and are known to cause disease outbreaks earlier as well. COVID-19 pandemic provides learning for the future, in particular the importance of environmental sustainability for controlling such outbreaks. A strategic plan can be developed involving policy-makers, organizations, and governments to control the onset and spread of the novel pathogens. This review-based study recommends that prevention of COVID-19 like pandemics from re-occurring is through tackling the issues related to the environment by controlling anthropogenic activities. It will also be important to track the lineage and future evolution course of such human pathogens so as to determine the nexus of environmental and biological factors in the development and spread of novel strains.

11.
Front Microbiol ; 11: 567768, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33193157

RESUMEN

Soil salinization has emerged as one of the prime environmental constraints endangering soil quality and agricultural productivity. Anthropogenic activities coupled with rapid pace of climate change are the key drivers of soil salinity resulting in degradation of agricultural lands. Increasing levels of salt not only impair structure of soil and its microbial activity but also restrict plant growth by causing harmful imbalance and metabolic disorders. Potential of secondary metabolites synthesized by halotolerant plant growth promoting rhizobacteria (HT-PGPR) in the management of salinity stress in crops is gaining importance. A wide array of secondary metabolites such as osmoprotectants/compatible solutes, exopolysaccharides (EPS) and volatile organic compounds (VOCs) from HT-PGPR have been reported to play crucial roles in ameliorating salinity stress in plants and their symbiotic partners. In addition, HT-PGPR and their metabolites also help in prompt buffering of the salt stress and act as biological engineers enhancing the quality and productivity of saline soils. The review documents prominent secondary metabolites from HT-PGPR and their role in modulating responses of plants to salinity stress. The review also highlights the mechanisms involved in the production of secondary metabolites by HT-PGPR in saline conditions. Utilizing the HT-PGPR and their secondary metabolites for the development of novel bioinoculants for the management of saline agro-ecosystems can be an important strategy in the future.

12.
J Adv Res ; 26: 69-82, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33133684

RESUMEN

BACKGROUND: The collective impact of climate change and soil salinity is continuously increasing the degraded lands across the globe, bringing agricultural productivity and food security under stress. The high concentration of salts in saline soils impose osmotic, ionic, oxidative and water stress in plants. Biological solutions can be the most reliable and sustainable approach to ensure food security and limit the use of agro-chemicals. AIM OF REVIEW: Halo-tolerant plant growth promoting rhizobacteria (HT-PGPR) are emerging as efficient biological tools to mitigate the toxic effects of high salt concentrations and improve the growth of plants, simultaneously remediating the degraded saline soils. The review explains the role of HT-PGPR in mitigating the salinity stress in plants through diverse mechanisms and concurrently leading to improvement of soil quality. KEY SCIENTIFIC CONCEPTS OF REVIEW: HT-PGPR are involved in alleviating the salinity stress in plants through a number of mechanisms evoking multipronged physiological, biochemical and molecular responses. These include changes in expression of defense-related proteins, exopolysaccharides synthesis, activation of antioxidant machinery, accumulation of osmolytes, maintaining the Na+ kinetics and improving the levels of phytohormones and nutrient uptake in plants. The modification of signaling by HT-PGPR inoculation under stress conditions elicits induced systemic resistance in plants which further prepares them against salinity stress. The role of microbial-mechanisms in remediating the saline soil through structural and compositional improvements is also important. Development of novel bioinoculants for saline soils based on the concepts presented in the review can be a sustainable approach in improving productivity of affected agro-ecosystems and simultaneously remediating them.

13.
3 Biotech ; 10(5): 210, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32351868

RESUMEN

Despite enhancing the crop yields, the so called green revolution (GR) has proven unsuccessful in assuring long term agricultural sustainability. The methods used for productivity enhancement during GR have not only proven to be problematic but have also resulted in deterioration of soil quality and several other issues related to ecosystems and health issues. The damage was mainly caused by the indiscriminate use of chemical fertilizers and insecticides. Various types of pesticides, are now known to be causing huge problems in the agro-ecosystems. In such a situation, where chemicals have caused or are causing irreversible impacts on agroecosystems, the use of biopesticides has emerged as a sustainable alternative leading to safe organic farming. At the global level, environmentally benign nature and target-specificity of biopesticides are gaining wide popularity. However, in developing countries like India usage of biopesticides is still minuscule in comparison to conventional chemical pesticides. Although the Indian government has encouraged the use of biopesticides by placing them into many of the agricultural schemes, at the grassroots level, biopesticides are facing many challenges. The lower adaptability and declining interest of farmers towards biopesticides have become a matter of concern. However, technological challenges related to production, manufacture and application in agroecosystems have also raised a question on their long-term sustainability. The main objective of this review is to highlight the developing trend in the field of biocontrol products in India. Apart from this, the review also focuses on the technological perspectives that are required for the long-term sustainability of biological control products in Indian agriculture and market.

14.
15.
Environ Sustain (Singap) ; 3(2): 121, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-38624399

RESUMEN

[This corrects the article DOI: 10.1007/s42398-020-00107-z.].

16.
Appl Opt ; 58(31): 8449-8456, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31873328

RESUMEN

In this paper, a micro-electro-mechanical system-based cantilever is integrated as a line defect on a photonic crystal silicon slab for optical switching applications. The elliptical holes are etched in the photonic crystal waveguide that result in wide transmission bandwidth of 56 nm in comparison to etched circular holes in the structure with a footprint of only ${12.5}\,\,{\unicode{x00B5}{\rm m}} \times {8}\,\,{\unicode{x00B5}{\rm m}}$12.5µm×8µm. The device is optimized for variation in height, the lattice constant, and semi-major and semi-minor axes in the optical range of the S-C-L band. It is shown that the response rise time of the device is 21 µs with very high extinction ratio of 30.4 dB and low insertion loss of 0.32 dB.

17.
Cancer Res ; 79(12): 3112-3124, 2019 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-31015228

RESUMEN

The cell membrane glycolipid GD2 is expressed by multiple solid tumors, including 88% of osteosarcomas and 98% of neuroblastomas. However, osteosarcomas are highly heterogeneous, with many tumors exhibiting GD2 expression on <50% of the individual cells, while some tumors are essentially GD2-negative. Anti-GD2 immunotherapy is the current standard of care for high-risk neuroblastoma, but its application to recurrent osteosarcomas, for which no effective therapies exist, has been extremely limited. This is, in part, because the standard assays to measure GD2 expression in these heterogeneous tumors are not quantitative and are subject to tissue availability and sampling bias. To address these limitations, we evaluated a novel, sensitive radiotracer [64Cu]Cu-Bn-NOTA-hu14.18K322A to detect GD2 expression in osteosarcomas (six patient-derived xenografts and one cell line) in vivo using positron emission tomography (PET). Tumor uptake of the radiolabeled, humanized anti-GD2 antibody [64Cu]Cu-Bn-NOTA-hu14.18K322A was 7-fold higher in modestly GD2-expressing osteosarcomas (32% GD2-positive cells) than in a GD2-negative tumor (9.8% vs. 1.3% of the injected dose per cc, respectively). This radiotracer also identified lesions as small as 29 mm3 in a 34% GD2-positive model of metastatic osteosarcoma of the lung. Radiolabeled antibody accumulation in patient-derived xenografts correlated with GD2 expression as measured by flow cytometry (Pearson r = 0.88, P = 0.01), distinguishing moderately GD2-expressing osteosarcomas (32%-69% GD2-positive cells) from high GD2 expressors (>99%, P < 0.05). These results support the utility of GD2 imaging with PET to measure GD2 expression in osteosarcoma and thus maximize the clinical impact of anti-GD2 immunotherapy. SIGNIFICANCE: In situ assessment of all GD2-positive osteosarcoma sites with a novel PET radiotracer could significantly impact anti-GD2 immunotherapy patient selection and enable noninvasive probing of correlations between target expression and therapeutic response.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Neoplasias Óseas/patología , Gangliósidos/antagonistas & inhibidores , Neoplasias Pulmonares/secundario , Recurrencia Local de Neoplasia/patología , Osteosarcoma/patología , Tomografía de Emisión de Positrones/métodos , Animales , Apoptosis , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/inmunología , Neoplasias Óseas/metabolismo , Proliferación Celular , Gangliósidos/inmunología , Humanos , Inmunoterapia , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/metabolismo , Ratones , Ratones Desnudos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/inmunología , Recurrencia Local de Neoplasia/metabolismo , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/inmunología , Osteosarcoma/metabolismo , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
18.
Front Microbiol ; 10: 2791, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31921005

RESUMEN

Soil salinity has emerged as a serious issue for global food security. It is estimated that currently about 62 million hectares or 20 percent of the world's irrigated land is affected by salinity. The deposition of an excess amount of soluble salt in cultivable land directly affects crop yields. The uptake of high amount of salt inhibits diverse physiological and metabolic processes of plants even impacting their survival. The conventional methods of reclamation of saline soil which involve scraping, flushing, leaching or adding an amendment (e.g., gypsum, CaCl2, etc.) are of limited success and also adversely affect the agro-ecosystems. In this context, developing sustainable methods which increase the productivity of saline soil without harming the environment are necessary. Since long, breeding of salt-tolerant plants and development of salt-resistant crop varieties have also been tried, but these and aforesaid conventional approaches are not able to solve the problem. Salt tolerance and dependence are the characteristics of some microbes. Salt-tolerant microbes can survive in osmotic and ionic stress. Various genera of salt-tolerant plant growth promoting rhizobacteria (ST-PGPR) have been isolated from extreme alkaline, saline, and sodic soils. Many of them are also known to mitigate various biotic and abiotic stresses in plants. In the last few years, potential PGPR enhancing the productivity of plants facing salt-stress have been researched upon suggesting that ST-PGPR can be exploited for the reclamation of saline agro-ecosystems. In this review, ST-PGPR and their potential in enhancing the productivity of saline agro-ecosystems will be discussed. Apart from this, PGPR mediated mechanisms of salt tolerance in different crop plants and future research trends of using ST-PGPR for reclamation of saline soils will also be highlighted.

19.
Front Microbiol ; 9: 2732, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30498482

RESUMEN

Microbial endophytes are present in all known plant species. The ability to enter and thrive in the plant tissues makes endophytes unique, showing multidimensional interactions within the host plant. Several vital activities of the host plant are known to be influenced by the presence of endophytes. They can promote plant growth, elicit defense response against pathogen attack, and can act as remediators of abiotic stresses. To date, most of the research has been done assuming that the interaction of endophytes with the host plant is similar to the plant growth-promoting (PGP) microbes present in the rhizosphere. However, a new appreciation of the difference of the rhizosphere environment from that of internal plant tissues is gaining attention. It would be interesting to explore the impact of endosymbionts on the host's gene expression, metabolism, and other physiological aspects essential in conferring resistance against biotic and abiotic stresses. A more intriguing and inexplicable issue with many endophytes that has to be critically evaluated is their ability to produce host metabolites, which can be harnessed on a large scale for potential use in diverse areas. In this review, we discuss the concept of endophytism, looking into the latest insights related to the multifarious interactions beneficial for the host plant and exploring the importance of these associations in agriculture and the environment and in other vital aspects such as human health.

20.
Front Microbiol ; 8: 1706, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28932218

RESUMEN

Increasing concentration of heavy metals (HM) due to various anthropogenic activities is a serious problem. Plants are very much affected by HM pollution particularly in contaminated soils. Survival of plants becomes tough and its overall health under HM stress is impaired. Remediation of HM in contaminated soil is done by physical and chemical processes which are costly, time-consuming, and non-sustainable. Metal-microbe interaction is an emerging but under-utilized technology that can be exploited to reduce HM stress in plants. Several rhizosphere microorganisms are known to play essential role in the management of HM stresses in plants. They can accumulate, transform, or detoxify HM. In general, the benefit from these microbes can have a vast impact on plant's health. Plant-microbe associations targeting HM stress may provide another dimension to existing phytoremediation and rhizoremediation uses. In this review, applied aspects and mechanisms of action of heavy metal tolerant-plant growth promoting (HMT-PGP) microbes in ensuring plant survival and growth in contaminated soils are discussed. The use of HMT-PGP microbes and their interaction with plants in remediation of contaminated soil can be the approach for the future. This low input and sustainable biotechnology can be of immense use/importance in reclaiming the HM contaminated soils, thus increasing the quality and yield of such soils.

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