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1.
J Basic Microbiol ; 62(6): 647-668, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35020220

RESUMEN

Endophytic microbiota opens a magnificent arena of metabolites that served as a potential source of medicines for treating a variety of ailments and having prospective uses in agriculture, food, cosmetics, and many more. There are umpteen reports of endophytes improving the growth and tolerance of plants. In addition, endophytes from lifesaving drug-producing plants such as Taxus, Nothapodytes, Catharanthus, and so forth have the ability to produce host mimicking compounds. To harness these benefits, it is imperative to isolate the true endophytes, not the surface microflora. The foremost step in endophyte isolation is the removal of epiphytic microbes from plant tissues, called as surface sterilization. The success of surface sterilization decides "what to grow" (the endophytes) and "what not to grow" (the epiphytes). It is very crucial to use an appropriate sterilant solution, concentration, and exposure time to ensure thorough surface disinfection with minimal damage to the endophytic diversity. Commonly used surface sterilants include sodium hypochlorite (2%-10%), ethanol (70%-90%), mercuric chloride (0.1%), formaldehyde (40%), and so forth. In addition, the efficiency could further be improved by pretreatment with surfactants such as Triton X-100, Tween 80, and Tween 20. This review comprehensively deals with the various sterilants and sterilization methods for the isolation of endophytic microbes. In addition, the mechanisms and rationale behind using specific surface sterilants have also been elaborated at length.


Asunto(s)
Plantas Medicinales , Taxus , Endófitos , Estudios Prospectivos , Esterilización
2.
Planta Med ; 86(13-14): 906-940, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32126583

RESUMEN

Azadirachta indica, commonly known as neem, is an evergreen tree of the tropics and sub-tropics native to the Indian subcontinent with demonstrated ethnomedicinal value and importance in agriculture as well as in the pharmaceutical industry. This ancient medicinal tree, often called the "wonder tree", is regarded as a chemical factory of diverse and complex compounds with a plethora of structural scaffolds that is very difficult to mimic by chemical synthesis. Such multifaceted chemical diversity leads to a fantastic repertoire of functional traits, encompassing a wide variety of biological activity and unique modes of action against specific and generalist pathogens and pests. Until now, more than 400 compounds have been isolated from different parts of neem including important bioactive secondary metabolites such as azadirachtin, nimbidin, nimbin, nimbolide, gedunin, and many more. In addition to its insecticidal property, the plant is also known for antimicrobial, antimalarial, antiviral, anti-inflammatory, analgesic, antipyretic, hypoglycaemic, antiulcer, antifertility, anticarcinogenic, hepatoprotective, antioxidant, anxiolytic, molluscicidal, acaricidal, and antifilarial properties. Notwithstanding the chemical and biological virtuosity of neem, it has also been extensively explored for associated microorganisms, especially a class of mutualists called endophytic microorganisms (or endophytes). More than 30 compounds, including neem "mimetic" compounds, have been reported from endophytes harbored in the neem trees in different ecological niches. In this review, we provide an informative and in-depth overview of the topic that can serve as a point of reference for an understanding of the functions and applications of a medicinal plant such as neem, including associated endophytes, within the overall theme of phytopathology. Our review further exemplifies the already-noted current surge of interest in plant and microbial natural products for implications both within the ecological and clinical settings, for a more secure and sustainable future.


Asunto(s)
Azadirachta , Insecticidas , Plantas Medicinales , Medicina Tradicional , Extractos Vegetales/farmacología
3.
Microb Pathog ; 119: 145-151, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29596880

RESUMEN

In this paper, we have reported the synthesis, characterization, and evaluation of antimicrobial and antioxidant potential of monodispersed Zinc Oxide (ZnO) nanoparticles synthesized by the room temperature precipitation (aqueous phase) and polyol method (organic phase). ZnO nanoparticle synthesized by both the methods had shown excellent DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging, metal chelating (MC), ABTS (2,2'-azino-bis; 3-ethylbenzothiazoline-6-sulphonic acid), hydroxyl radical and superoxide radical scavenging activity (SAS). Scavenging activities were assayed within a concentration range of 25-75 ng ml-1. The antibacterial activities with MIC were investigated against two Gram-positive bacteria Streptococcus mutans (MTCC 497) and S. pyogens (MTCC 1926); three Gram negative bacteria Vibrio cholerae (MTCC 3906), Shigella flexneri (MTCC 1457) and Salmonella typhii (MTCC 1252). ZnO nanoparticles synthesized by the polyol method showed better MIC values against both Gram-positive and Gram-negative bacteria as compared to particles synthesized by aqueous precipitation method. Present study demonstrates the successful synthesis of ZnO nanoparticles with antioxidant property and significant broad spectrum antibacterial activity against several clinical bacterial pathogens.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Nanopartículas/química , Óxido de Zinc/farmacología , Antibacterianos/síntesis química , Benzotiazoles , Compuestos de Bifenilo , Quelantes , Depuradores de Radicales Libres , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Radical Hidroxilo , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Picratos , Polímeros , Espectroscopía Infrarroja por Transformada de Fourier , Ácidos Sulfónicos , Superóxidos , Difracción de Rayos X , Óxido de Zinc/síntesis química
4.
Med Sci Law ; 54(3): 158-66, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24166687

RESUMEN

Estimating time since death (TSD) with fair accuracy from postmortem changes still remains an important but difficult task to be performed by every autopsy surgeon in medicolegal scenario. The aim of the present study was to estimate TSD from electrolyte analysis of postmortem vitreous humour collected from samples under semi-arid climate. Vitreous humour was collected from 210 dead bodies brought to University College of Medical Sciences and Guru Teg Bahadur Hospital, Delhi, during the period of November 2010 to April 2012. The vitreous samples were analysed for sodium, potassium, calcium, chloride and glucose. The results showed a significant positive relationship between TSD and potassium (r = 0.841, p = 0.000) and a weak negative relationship between TSD and sodium (r = -0.137, p = 0.048) and glucose (r = -0.241, p = 0.000), whereas no significant relationship could be established between TSD and calcium (r = 0.055, p = 0.429) and chloride (r = 0.075, p = 0.11).


Asunto(s)
Calcio/análisis , Electrólitos/análisis , Glucosa/análisis , Cambios Post Mortem , Cuerpo Vítreo/química , Biomarcadores/análisis , Clima , Estudios Transversales , Femenino , Humanos , India , Masculino , Factores de Tiempo
5.
Plant Physiol Biochem ; 212: 108731, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38761545

RESUMEN

Seed endophytic bacteria have been shown to promote the growth and development of numerous plants. However, the underlying mechanism still needs to be better understood. The present study aims to investigate the role of a seed endophytic bacterium Lysinibacillus sp. (ZM1) in promoting plant growth and shaping the root architecture of maize seedlings. The study explores how bacteria-mediated auxin biosynthesis and nitrogen metabolism affect plant growth promotion and shape the root architecture of maize seedlings. The results demonstrate that ZM1 inoculation significantly enhances root length, root biomass, and the number of seminal roots in maize seedlings. Additionally, the treated seedlings exhibit increased shoot biomass and higher levels of photosynthetic pigments. Confocal laser scanning microscopy (CLSM) analysis revealed extensive colonization of ZM1 on root hairs, as well as in the cortical and stellar regions of the root. Furthermore, LC-MS analysis demonstrated elevated auxin content in the roots of the ZM1 treated maize seedlings compared to the uninoculated control. Inoculation with ZM1 significantly increased the levels of endogenous ammonium content, GS, and GOGAT enzyme activities in the roots of treated maize seedlings compared to the control, indicating enhanced nitrogen metabolism. Furthermore, inoculation of bacteria under nitrogen-deficient conditions enhanced plant growth, as evidenced by increased root shoot length, fresh and dry weights, average number of seminal roots, and content of photosynthetic pigments. Transcript analysis indicated upregulation of auxin biosynthetic genes, along with genes involved in nitrogen metabolism at different time points in roots of ZM1-treated maize seedlings. Collectively, our findings highlight the positive impact of Lysinibacillus sp. ZM1 inoculation on maize seeds by improving root architecture through modulation of auxin biosynthesis and affecting various nitrogen metabolism related parameters. These findings provide valuable insights into the potential utilization of seed endophytic bacteria as biofertilizers to enhance plant growth and yield in nutrient deficient soils.


Asunto(s)
Bacillaceae , Ácidos Indolacéticos , Nitrógeno , Raíces de Plantas , Zea mays , Zea mays/microbiología , Zea mays/metabolismo , Zea mays/crecimiento & desarrollo , Ácidos Indolacéticos/metabolismo , Nitrógeno/metabolismo , Raíces de Plantas/microbiología , Raíces de Plantas/metabolismo , Bacillaceae/metabolismo , Endófitos/metabolismo , Endófitos/fisiología , Semillas/microbiología , Semillas/metabolismo , Semillas/crecimiento & desarrollo , Plantones/microbiología , Plantones/metabolismo , Plantones/crecimiento & desarrollo
6.
Microb Ecol ; 64(2): 388-98, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22430503

RESUMEN

A total of 1,151 endophytic fungal isolates representing 29 taxa were isolated from symptom-less, surface-sterilized segments of stem, leaf, petiole, and root of Tinospora cordifolia which had been collected at three locations differing in air pollution in India (Ramnagar, Banaras Hindu University, Maruadih) during three seasons (summer, monsoon, winter). Endophytes were most abundant in leaf tissues (29.38% of all isolates), followed by stem (18.16%), petiole (10.11%), and root segments (6.27%). The frequency of colonization (CF) varied more strongly among tissue type and season than location. CF was maximal during monsoon followed by winter and minimal during summer. A species each of Guignardia and Acremonium could only be isolated from leaves, whereas all other species occurred in at least two tissue types. Penicillium spp. were dominant (12.62% of all isolates), followed by Colletotrichum spp. (11.8%), Cladosporium spp. (8.9%), Chaetomium globosum (8.1%), Curvularia spp. (7.6%), and Alternaria alternata (6.8%). Species richness, evenness, and the Shannon-Wiener diversity index followed the same pattern as the CF with the tissue type and the season having the greatest effect on these indices, suggesting that tissue type and season are more influential than geography. Dissimilarity of endophyte communities in regards to species composition was highest among seasons. Colletotrichum linicola occurred almost exclusively in winter, Fusarium oxysporum only in winter and summer but never during monsoon and Curvularia lunata only in winter and during monsoon but never in summer. Emissions of NO(2), SO(2), and suspended particulate matter were negatively correlated with the CF. Ozone did not have any effect. The frequency of most species declined with increasing pollution, but some showed an opposite trend (e.g., Aspergillus flavus). Five unnamed taxa (sterile mycelia) were identified as Aspergillus tubingensis, Colletotrichum crassipes, Botryosphaeria rhodina, Aspergillus sydowii, and Pseudofusicoccum violaceum, using molecular tools. Fifteen of the 29 endophyte taxa exhibited antibacterial activity. B. rhodina (JQ031157) and C. globosum showed activity against all bacterial human pathogens tested, with the former showing higher activity than the latter.


Asunto(s)
Ascomicetos/aislamiento & purificación , Endófitos/aislamiento & purificación , Plantas Medicinales/microbiología , Estaciones del Año , Tinospora/microbiología , Antibacterianos/farmacología , Ascomicetos/clasificación , Ascomicetos/genética , Ecosistema , Endófitos/clasificación , Endófitos/genética , Hongos , Humanos , India , Pruebas de Sensibilidad Microbiana , Hojas de la Planta/microbiología , Raíces de Plantas/microbiología , Tallos de la Planta/microbiología , Especificidad de la Especie , Esporas Bacterianas/efectos de los fármacos
8.
PeerJ ; 10: e13879, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35971430

RESUMEN

Escherichia coli is generally considered a bacterium associated with animal microbiomes. However, we present evidence that E. coli may also mutualistically colonize roots of plant species, even to the extent that it may become endophytic in plants. In this study we used GFP tagged E. coli to observe its colonization and effects on tomato (Solanum lycopersicum) and Bermuda grass (Cynodon dactylon) seedling development and growth. Inoculation with the bacterium significantly improved root development of both seedlings tested. Treatment also increased the photosynthetic pigments in Bermuda grass seedlings. However, effects on shoot length in both seedlings were not significant. This bacterium was found to produce indole acetic acid (IAA) up to 8.68 ± 0.43 µg ml-1 in the broth medium amended with tryptophan. Effects on seedling root growth could, in part, be explained by IAA production. Bacteria successfully colonized the root surfaces and interiors of both seedlings. Tagged bacteria expressing the GFP were observed in the vascular tissues of Bermuda grass seedling roots. Seedlings with bacteria showed greater survival and were healthier than seedlings without bacteria, indicating that E. coli set up a successful mutualistic symbiosis with seedlings. E. coli is not commonly considered to be a plant endophyte but is more generally considered to be a crop contaminant. In this study we show that E. coli may also be an endophyte in plant tissues.


Asunto(s)
Plantones , Solanum lycopersicum , Simbiosis , Cynodon , Escherichia coli/genética , Raíces de Plantas , Endófitos , Bacterias
9.
Microbiol Res ; 265: 127201, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36167006

RESUMEN

The genus Burkholderia has proven potential in improving plant performance. In recent decades, a huge diversity of Burkholderia spp. have been reported with diverse capabilities of plant symbiosis which could be harnessed to enhance plant growth and development. Colonization of endophytic Burkholderia spp. have been extensively studied through techniques like advanced microscopy, fluorescent labelling, PCR based assays, etc., and found to be systemically distributed in plants. Thus, use of these biostimulant microbes holds the promise of improving quality and quantity of crops. The endophytic Burkholderia spp. have been found to support plant functions along with boosting nutrient availability, especially under stress. Endophytic Burkholderia spp. improve plant survival against deadly pathogens via mechanisms like competition, induced systemic resistance, and antibiosis. At the same time, they are reported to extend plant tolerance towards multiple abiotic stresses especially drought, salinity, and cold. Several attempts have been made to decipher the potential of Burkholderia spp. by genome mining, and these bacteria have been found to harbour genes for plant symbiosis and for providing multiple benefits to host plants. Characteristics specific for host recognition and nutrient acquisition were confirmed in endophytic Burkholderia by genomics and proteomics-based studies. This could pave the way for harnessing Burkholderia spp. for biotechnological applications like biotransformation, phytoremediation, insecticidal activity, antimicrobials, etc. All these make Burkholderia spp. a promising microbial agent in improving plant performance under multiple adversities. Thus, the present review highlights critical roles of endophytic Burkholderia spp., their colonization, alleviation of biotic and abiotic stresses, biotechnological applications and genomic insights.


Asunto(s)
Burkholderia , Burkholderia/genética , Endófitos/metabolismo , Desarrollo de la Planta , Plantas/microbiología , Simbiosis
10.
Front Microbiol ; 12: 774293, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34956137

RESUMEN

Seed endophytic bacteria (SEB) are primary symbionts that play crucial roles in plant growth and development. The present study reports the isolation of seven culturable SEB including Kosakonia cowanii (KAS1), Bacillus subtilis (KAS2), Bacillus tequilensis (KAS3), Pantoea stewartii (KAS4), Paenibacillus dendritiformis (KAS5), Pseudomonas aeruginosa (KAS6), and Bacillus velezensis (KAS7) in pearl millet seeds. All the isolates were characterized for their plant growth promoting activities. Most of the SEB also inhibited the growth of tested fungal phytopathogens in dual plate culture. Removal of these SEB from seeds compromised the growth and development of seedlings, however, re-inoculation with the SEB (Kosakonia cowanii, Pantoea stewartii, and Pseudomonas aeruginosa) restored the growth and development of seedlings significantly. Fluorescence microscopy showed inter and intracellular colonization of SEB in root parenchyma and root hair cells. Lipopeptides were extracted from all three Bacillus spp. which showed strong antifungal activity against tested fungal pathogens. Antifungal lipopeptide genes were also screened in Bacillus spp. After lipopeptide treatment, live-dead staining with fluorescence microscopy along with bright-field and scanning electron microscopy (SEM) revealed structural deformation and cell death in Fusarium mycelia and spores. Furthermore, the development of pores in the membrane and leakages of protoplasmic substances from cells and ultimately death of hyphae and spores were also confirmed. In microcosm assays, treatment of seeds with Bacillus subtilis or application of its lipopeptide alone significantly protected seedlings from Fusarium sp. infection.

11.
Microorganisms ; 7(5)2019 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-31117261

RESUMEN

Digitaria ischaemum (Schreb.) Schreb. ex Muhl. and Poa annua L. are competitive, early successional species which are usually considered weeds in agricultural and turfgrass systems. Bacteria and fungi associated with D. ischaemum and P. annua seed may contribute to their competitiveness by antagonizing competitor forbs, and were studied in axenic culture. Pantoea spp. were the most common bacterial isolate of D. ischaemum seed, while Epicoccum and Curvularia spp. were common fungal isolates. A variety of species were collected from non-surface sterilized P. annua. Certain Pantoea spp. isolates were antagonistic to competitor forbs Taraxacum officinale, Trifolium repens. All bacterial isolates that affected T. officinale mortality were isolated from D. ischaemum seed while none of the P. annua isolates affected mortality. Two selected bacterial isolates identified as Pantoea ananatis were evaluated further on D. ischaemum, T. repens (a competitor forb) and P. annua (a competitor grass) alone and in combination with a Curvularia sp. fungus. These bacteria alone caused >65% T. repens seedling mortality but did not affect P. annua seedling mortality. These experiments demonstrate that Pantoea ananatis associated with D. ischaemum seeds is antagonistic to competitor forbs in axenic culture. The weedy character of D. ischaemum could at least in part stem from the possession of bacteria that are antagonistic to competitor species.

12.
Dalton Trans ; 48(30): 11391-11403, 2019 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-31282909

RESUMEN

The present study deals with the material tailoring of Mg(NH2)2-2LiH through dual borohydrides: the reactive LiBH4 and the non-reactive NaBH4. Furthermore, a pulverizer, as well as a catalyst FeTi, has been added in order to facilitate hydrogen sorption. Addition of LiBH4 to LiNH2 in a 1 : 3 molar ratio leads to the formation of Li4(BH4)(NH2)3 which also acts as a catalyst. However, the addition of NaBH4 doesn't lead to any compound formation but shows a catalytic effect. The onset dehydrogenation temperature of thermally treated Mg(NH2)2-2LiH/(Li4(BH4)(NH2)3-NaBH4) is 142 °C as against 196 °C for the basic material Mg(NH2)2-2LiH. However, with the FeTi catalyzed Mg(NH2)2-2LiH/(Li4(BH4)(NH2)3-NaBH4, it has been reduced to 120 °C. This is better than other similar amide/hydride composites where it is 149 °C (when the basic material is catalyzed with LiBH4). The FeTi catalyzed Mg(NH2)2-2LiH/(Li4(BH4)(NH2)3-NaBH4 sample shows better de/re-hydrogenation kinetics as it desorbs 3.9 ± 0.04 wt% and absorbs nearly 4.1 ± 0.04 wt% both within 30 min at 170 °C (with the H2 pressure being 0.1 MPa for desorption and 7 MPa for absorption). The eventual hydrogen storage capacity of Mg(NH2)2-2LiH/(Li4(BH4)(NH2)3-NaBH4 together with FeTi has been found to be ∼5.0 wt%. To make the effect of catalysts intelligible, we have put forward in a schematic way the role of Li and Na borohydrides with FeTi for improving the hydrogen sorption properties of Mg(NH2)2-2LiH.

13.
Pest Manag Sci ; 75(10): 2558-2565, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31228333

RESUMEN

Endophytes are microbes (mostly bacteria and fungi) present asymptomatically in plants. Endophytic microbes are often functional in that they may carry nutrients from the soil into plants, modulate plant development, increase stress tolerance of plants, suppress virulence in pathogens, increase disease resistance in plants, and suppress development of competitor plant species. Endophytic microbes have been shown to: (i) obtain nutrients in soils and transfer nutrients to plants in the rhizophagy cycle and other nutrient-transfer symbioses; (ii) increase plant growth and development; (iii) reduce oxidative stress of hosts; (iv) protect plants from disease; (v) deter feeding by herbivores; and (vi) suppress growth of competitor plant species. Because of the effective functions of endophytic microbes, we suggest that endophytic microbes may significantly reduce use of agrochemicals (fertilizers, fungicides, insecticides, and herbicides) in the cultivation of crop plants. The loss of endophytic microbes from crop plants during domestication and long-term cultivation could be remedied by transfer of endophytes from wild relatives of crops to crop species. Increasing atmospheric carbon dioxide levels could reduce the efficiency of the rhizophagy cycle due to repression of reactive oxygen used to extract nutrients from microbes in roots. © 2019 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Producción de Cultivos/métodos , Protección de Cultivos/métodos , Productos Agrícolas/microbiología , Endófitos/fisiología , Simbiosis , Productos Agrícolas/crecimiento & desarrollo , Productos Agrícolas/fisiología , Fertilizantes/análisis
14.
Microorganisms ; 6(3)2018 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-30227634

RESUMEN

In this paper, we describe a mechanism for the transfer of nutrients from symbiotic microbes (bacteria and fungi) to host plant roots that we term the 'rhizophagy cycle.' In the rhizophagy cycle, microbes alternate between a root intracellular endophytic phase and a free-living soil phase. Microbes acquire soil nutrients in the free-living soil phase; nutrients are extracted through exposure to host-produced reactive oxygen in the intracellular endophytic phase. We conducted experiments on several seed-vectored microbes in several host species. We found that initially the symbiotic microbes grow on the rhizoplane in the exudate zone adjacent the root meristem. Microbes enter root tip meristem cells-locating within the periplasmic spaces between cell wall and plasma membrane. In the periplasmic spaces of root cells, microbes convert to wall-less protoplast forms. As root cells mature, microbes continue to be subjected to reactive oxygen (superoxide) produced by NADPH oxidases (NOX) on the root cell plasma membranes. Reactive oxygen degrades some of the intracellular microbes, also likely inducing electrolyte leakage from microbes-effectively extracting nutrients from microbes. Surviving bacteria in root epidermal cells trigger root hair elongation and as hairs elongate bacteria exit at the hair tips, reforming cell walls and cell shapes as microbes emerge into the rhizosphere where they may obtain additional nutrients. Precisely what nutrients are transferred through rhizophagy or how important this process is for nutrient acquisition is still unknown.

15.
Microorganisms ; 6(1)2018 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-29518024

RESUMEN

Non-cultivated plants carry microbial endophytes that may be used to enhance development and disease resistance of crop species where growth-promoting and protective microbes may have been lost. During seedling establishment, seedlings may be infected by several fungal pathogens that are seed or soil borne. Several species of Fusarium, Pythium and other water moulds cause seed rots during germination. Fusarium blights of seedlings are also very common and significantly affect seedling development. In the present study we screened nine endophytic bacteria isolated from the seeds of invasive Phragmites australis by inoculating onto rice, Bermuda grass (Cynodon dactylon), or annual bluegrass (Poa annua) seeds to evaluate plant growth promotion and protection from disease caused by Fusarium oxysporum. We found that three bacteria belonging to genus Pseudomonas spp. (SLB4-P. fluorescens, SLB6-Pseudomonas sp. and SY1-Pseudomonas sp.) promoted seedling development, including enhancement of root and shoot growth, and stimulation of root hair formation. These bacteria were also found to increase phosphate solubilization in in vitro experiments. Pseudomonas sp. (SY1) significantly protected grass seedlings from Fusarium infection. In co-culture experiments, strain SY1 strongly inhibited fungal pathogens with 85.71% growth inhibition of F. oxysporum, 86.33% growth inhibition of Curvularia sp. and 82.14% growth inhibition of Alternaria sp. Seedlings previously treated with bacteria were found much less infected by F. oxysporum in comparison to non-treated controls. On microscopic observation we found that bacteria appeared to degrade fungal mycelia actively. Metabolite products of strain SY1 in agar were also found to inhibit fungal growth on nutrient media. Pseudomonas sp. (SY1) was found to produce antifungal volatiles. Polymerase chain reaction (PCR) amplification using specific primers for pyrrolnitirin synthesis and HCN (hydrogen cyanide) production suggested presence of genes for both compounds in the genome of SY1. HCN was detected in cultures of SY1. We conclude that microbes from non-cultivated plants may provide disease protection and promote growth of crop plants.

16.
World Neurosurg ; 114: 323-325, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29572171

RESUMEN

BACKGROUND: Anterior sacral meningocele (ASM) leading to secondary rectothecal fistula is extremely rare, and to date only 5 such cases have been described in the world literature. CASE DESCRIPTION: We describe an uncomplicated case of a 52-year-old female patient presenting with cerebrospinal fluid leak from the anus who was investigated and found to have an ASM with rectothecal fistula. The ASM and rectothecal fistula were subsequently repaired using a posterior approach. Pertinent literature review, clinical findings, neuroimaging, and surgical management are described for these rare lesions. CONCLUSION: Early diagnosis and surgical disconnection of the fistulous tract led to satisfactory outcome in the present case and avoided the catastrophic complication of meningitis.


Asunto(s)
Canal Anal/diagnóstico por imagen , Rinorrea de Líquido Cefalorraquídeo/diagnóstico por imagen , Fístula del Sistema Digestivo/diagnóstico por imagen , Meningocele/diagnóstico por imagen , Sacro/diagnóstico por imagen , Canal Anal/cirugía , Rinorrea de Líquido Cefalorraquídeo/etiología , Rinorrea de Líquido Cefalorraquídeo/cirugía , Fístula del Sistema Digestivo/complicaciones , Fístula del Sistema Digestivo/cirugía , Femenino , Humanos , Meningocele/complicaciones , Meningocele/cirugía , Persona de Mediana Edad , Sacro/cirugía
17.
World Neurosurg ; 107: 795-802, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28842231

RESUMEN

BACKGROUND: Opinions vary regarding optimal treatment of unstable hangman's fractures, including rigid orthosis and internal fixation. The anatomy of upper cervical spine is complex. The advent of intraoperative 3-dimensional navigation systems facilitates safe and accurate instrumentation. OBJECTIVE: To evaluate radiologic parameters of fracture morphology in unstable hangman's fracture in preoperative and postoperative period and accuracy of inserting axis pedicle screws by using intraoperative computed tomography-based navigation. METHODS: Fifteen patients with unstable hangman's fractures with age ranging from 17 years to 81 years were operated using computed tomography-based navigation from September 2011 to march 2016. Patient's age, sex, mechanism of injury, associated injuries, and neurologic status were noted. Clinical outcome, accuracy of screw insertion, preoperative and postoperative displacement, and angulation of C2 over C3 and bony fusion were assessed. RESULTS: Overall, 76 screws were inserted including 30 screws in C2 pedicle with 2 (2/60; 6.7%) malplaced screws in C2 pedicle. Mean follow-up period was 34 ± 18 months (range 7-80 months). Mean hospital stay was 12.8 ± 2.4 days. Mean preoperative and postoperative displacements were 4.09 mm ± 1.78 mm and 1.82 mm ± 1.14 mm respectively with a mean reduction of 2.27 mm ± 1.49 mm. Mean preoperative angulation was 7.23° ± 11.96° and postoperative angulation was 2.32° ± 4.77° with a mean reduction of 5.11° ± 11.96°. Bony fusion was achieved and rotation was preserved at C1-C2 joint in all cases. CONCLUSIONS: Intraoperative O-arm-based navigation is a safe, accurate, and effective tool for screw placement in patients with unstable hangman fracture and achieves good anatomical reduction.


Asunto(s)
Fijación Interna de Fracturas , Tornillos Pediculares , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/cirugía , Cirugía Asistida por Computador , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Imagenología Tridimensional , Tiempo de Internación , Masculino , Persona de Mediana Edad , Neuronavegación , Estudios Retrospectivos , Fracturas de la Columna Vertebral/etiología , Resultado del Tratamiento , Adulto Joven
18.
Sci Rep ; 7(1): 3745, 2017 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-28623306

RESUMEN

Fungal endophytes were isolated from leaf, bark and stem of Tectona grandis Linn.f. sampled at four geographical locations in winter, summer and monsoon seasons. The recovered 5089 isolates were assigned to 45 distinct morphotypes based on morphology. The sequences of the internal transcribed spacers (ITS) of the nrDNA of some morphotypes were identical, but morphological differences were strong enough to consider these morphotypes as separate species. Forty-three morphotypes were assigned to ascomycotina and two to basidiomycotina. Ascomycotina was the predominating group with 99.7% of total isolates followed by basidiomycotina with only 0.3% of total isolates. Diaporthe (Phomopsis) species dominated the communities independently on tissue type, location or season. More than 60% of the examined tissue pieces were colonized by members of this species complex. While these endophytes are ubiquitous others were tissue or location specific. Tissue type had the strongest effect on the species evenness of the endophytic assemblage followed by geographical location and season. However, Shannon-Wiener index (H') significantly (p ≤ 0.001) varied with all three factors i.e. season, location and tissue type. Leaves supported the highest diversity across all the seasons and locations. In conclusion, all the three factors together determined the structure of endophytic mycobiota assemblage of T. grandis.


Asunto(s)
Ascomicetos , Basidiomycota , Lamiaceae/microbiología , Micobioma/fisiología , Estaciones del Año , Ascomicetos/aislamiento & purificación , Ascomicetos/fisiología , Basidiomycota/aislamiento & purificación , Basidiomycota/fisiología
19.
Front Microbiol ; 8: 1126, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28674526

RESUMEN

Grape skin and turmeric extracts having the major components resveratrol and curcumin, respectively, were used for the induction of cryptic and bioactive metabolites in an endophytic fungus Colletotrichum gloeosporioides isolated from Syzygium cumini. The increase in total amount of crude compounds in grape skin and turmeric extract treated cultures was 272.48 and 174.32%, respectively, compared to the untreated control. Among six human pathogenic bacteria tested, the maximum inhibitory activity was found against Aeromonas hydrophila IMS/GN11 while no inhibitory activity was observed against Enterococcus faecalis IMS/GN7. The crude compounds derived from turmeric extract treated cultures showed the highest DPPH free radicals scavenging activity (86.46% inhibition) followed by compounds from grape skin treated cultures (11.80% inhibition) and the control cultures (1.92% inhibition). Both the treatments significantly (p ≤ 0.05) increased the antibacterial and antioxidant activities of crude metabolites compared to the control. HPLC profiling of crude compounds derived from grape skin and turmeric extract treated cultures revealed the presence of additional 20 and 14 cryptic compounds, respectively, compared to the control. These findings advocate the future use of such dietary components in induced production of cryptic and bioactive metabolites.

20.
Leg Med (Tokyo) ; 8(1): 1-4, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16054855

RESUMEN

Strangulation is one of the common modes of violent asphyxias. Frequently, the deaths from strangulation are homicidal in nature. To study the pattern of the strangulation deaths in the capital city of Delhi, a retrospective analysis of 10 years records from the period 1993-2002 was undertaken in the department of Forensic Medicine and Toxicology at UCMS and GTB Hospital. During the above period, 8385 Forensic autopsies were conducted out of these 98 (1.17%) cases were found to be of strangulation. These 98 cases were analyzed in detail and showed that: (a) incidence of strangulation have increased many folds in comparison in 1970s; (b) maximum incidence of strangulation is amongst individuals in third decade of life; (c) male, female ratio was 3:2; (d) ligating material was found present in neck in 40% cases; (e) fractures of the neck bones/cartilage were observed in 80% cases; and (f) other associated injuries were seen in as high as approximately 90% of cases. The paper describes and discusses the findings in detail.


Asunto(s)
Asfixia/mortalidad , Traumatismos del Cuello/mortalidad , Accidentes/estadística & datos numéricos , Adolescente , Adulto , Distribución por Edad , Vértebras Cervicales/lesiones , Niño , Preescolar , Femenino , Medicina Legal , Fracturas Óseas/patología , Fracturas del Cartílago/patología , Homicidio/estadística & datos numéricos , Humanos , India/epidemiología , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Distribución por Sexo , Cartílago Tiroides/lesiones
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