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1.
J Appl Microbiol ; 135(2)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38341275

RESUMO

AIMS: The study aims to explore antifungal properties of bacillibactin siderophore produced by the plant growth-promoting rhizobacterium (PGPR) Bacillus subtilis against fungal phytopathogens Alternaria porri and Fusarium equiseti isolated from Solanum lycopersicum and Solanum melongena plants. METHODS AND RESULTS: Alternaria porri and F. equiseti were isolated from infected plants of eggplant and tomato, respectively. A plate assay was employed to assess the effect of bacillibactin against the phytopathogens. The antifungal potential of the PGPR was evaluated by estimation of dry fungal biomass, visualization of cellular deformity using compound and scanning electron microscopy, antioxidative enzyme assay and analysis of membrane damage via using lipid peroxidation. Inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis was employed to investigate changes in intracellular iron content. The impact of bacillibactin on pathogenesis was evaluated by infecting detached leaves of S. lycopersicum and S. melongena plants with both the pathogens and treating the infected leaves with bacillibactin. Leaves were further investigated for ROS accumulation, extent of necrosis and cell death. Our findings revealed significant damage to the hyphal structure of A. porri and F. equiseti following treatment with bacillibactin. Biomass reduction, elevated antioxidative enzyme levels, and membrane damage further substantiated the inhibitory effects of the siderophore on fungal growth. ICP-AES analysis indicates an increase in intracellular iron content suggesting enhanced iron uptake facilitated by bacillibactin. Moreover, application of 1500 µg ml-1 bacillibactin on infected leaves demonstrated a substantial inhibition of ROS accumulation, necrosis, and cell death upon bacillibactin treatment. CONCLUSIONS: This study confirms the potent antagonistic activity of bacillibactin against both the phytopathogens A. porri and F. equiseti growth, supporting its potential as a promising biological control agent for fungal plant diseases. Bacillibactin-induced morphological, physiological, and biochemical alterations in the isolated fungi and pathogen-infected leaves highlight the prospects of bacillibactin as an effective and sustainable solution to mitigate economic losses associated with fungal infections in vegetable crops.


Assuntos
Alternaria , Solanum lycopersicum , Solanum , Antifúngicos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Solanum/metabolismo , Sideróforos/farmacologia , Produtos Agrícolas/metabolismo , Ferro , Necrose , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia
2.
Int J Mol Sci ; 24(5)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36901740

RESUMO

Lacrimal gland inflammation triggers dry eye disease through impaired tear secretion by the epithelium. As aberrant inflammasome activation occurs in autoimmune disorders including Sjögren's syndrome, we analyzed the inflammasome pathway during acute and chronic inflammation and investigated its potential regulators. Bacterial infection was mimicked by the intraglandular injection of lipopolysaccharide (LPS) and nigericin, known to activate the NLRP3 inflammasome. Acute injury of the lacrimal gland was induced by interleukin (IL)-1α injection. Chronic inflammation was studied using two Sjögren's syndrome models: diseased NOD.H2b compared to healthy BALBc mice and Thrombospondin-1-null (TSP-1-/-) compared to TSP-1WTC57BL/6J mice. Inflammasome activation was investigated by immunostaining using the R26ASC-citrine reporter mouse, by Western blotting, and by RNAseq. LPS/Nigericin, IL-1α and chronic inflammation induced inflammasomes in lacrimal gland epithelial cells. Acute and chronic inflammation of the lacrimal gland upregulated multiple inflammasome sensors, caspases 1/4, and interleukins Il1b and Il18. We also found increased IL-1ß maturation in Sjögren's syndrome models compared with healthy control lacrimal glands. Using RNA-seq data of regenerating lacrimal glands, we found that lipogenic genes were upregulated during the resolution of inflammation following acute injury. In chronically inflamed NOD.H2b lacrimal glands, an altered lipid metabolism was associated with disease progression: genes for cholesterol metabolism were upregulated, while genes involved in mitochondrial metabolism and fatty acid synthesis were downregulated, including peroxisome proliferator-activated receptor alpha (PPARα)/sterol regulatory element-binding 1 (SREBP-1)-dependent signaling. We conclude that epithelial cells can promote immune responses by forming inflammasomes, and that sustained inflammasome activation, together with an altered lipid metabolism, are key players of Sjögren's syndrome-like pathogenesis in the NOD.H2b mouse lacrimal gland by promoting epithelial dysfunction and inflammation.


Assuntos
Aparelho Lacrimal , Síndrome de Sjogren , Animais , Camundongos , Aparelho Lacrimal/patologia , Inflamassomos/metabolismo , Trombospondina 1/metabolismo , Metabolismo dos Lipídeos , Lipopolissacarídeos/metabolismo , Nigericina , Camundongos Endogâmicos NOD , Camundongos Endogâmicos C57BL , Inflamação/metabolismo , Células Epiteliais/metabolismo , Imunidade
3.
Int Microbiol ; 23(2): 277-286, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31655918

RESUMO

Siderophores (Gk iron carriers) are low molecular weight secondary metabolites produced by bacteria, fungi, and plants that have strong binding affinity for iron. Owing to their iron-chelating ability, they are produced mainly when the organism faces iron scarcity. The present study empirically investigated the importance of applying hydroxamate siderophore extracted from Aspergillus nidulans to the cells of Bacillus subtilis for bioremediation of cadmium salt. This investigation deals with siderophore-mediated intracellular Cd accumulation by bacterial cells, growth estimation, biochemical assays like lipid peroxidation, total protein content, carbohydrate content, and iron content estimation. In silico docking and STRING analyses revealed specific interaction between Aspergillus siderophore and receptors present on B. subtilis. Estimation of intracellular Cd by atomic absorption spectroscopy showed more accumulation of Cd ions by B. subtilis in the presence of hydroxamate siderophore. This suggests a possibility of confiscating environmental Cd2+ by utilizing metal chelation property of siderophores and hence can lead to emerging bioremediation mechanisms for heavy metals. In silico studies support experimental investigation and suggest higher affinity of siderophore for Cd ions as compared with ferric ions.


Assuntos
Bacillus subtilis/metabolismo , Cádmio/metabolismo , Metais Pesados/metabolismo , Sideróforos , Aspergillus nidulans/metabolismo , Biodegradação Ambiental , Ferro/metabolismo , Simulação de Acoplamento Molecular , Sideróforos/biossíntese , Sideróforos/metabolismo
4.
Int J Mol Sci ; 21(23)2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33271951

RESUMO

Sjögren's syndrome (SS) is a systemic autoimmune disorder affecting approximately 3% of the population in the United States. This disease has a female predilection and affects exocrine glands, including lacrimal and salivary glands. Dry eyes and dry mouths are the most common symptoms due to the loss of salivary and lacrimal gland function. Symptoms become more severe in secondary SS, where SS is present along with other autoimmune diseases like systemic lupus erythematosus, systemic sclerosis, or rheumatoid arthritis. It is known that aberrant activation of immune cells plays an important role in disease progression, however, the mechanism for these pathological changes in the immune system remains largely unknown. This review highlights the role of different immune cells in disease development, therapeutic treatments, and future strategies that are available to target various immune cells to cure the disease.


Assuntos
Terapia Biológica , Suscetibilidade a Doenças , Imunidade Inata , Síndrome de Sjogren/imunologia , Síndrome de Sjogren/terapia , Animais , Autoimunidade , Linfócitos B/imunologia , Linfócitos B/metabolismo , Terapia Biológica/métodos , Terapia Combinada , Citocinas/metabolismo , Gerenciamento Clínico , Suscetibilidade a Doenças/imunologia , Humanos , Macrófagos/imunologia , Macrófagos/metabolismo , Glândulas Salivares/imunologia , Glândulas Salivares/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Resultado do Tratamento
5.
World J Microbiol Biotechnol ; 36(12): 178, 2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33128090

RESUMO

Siderophores are metal chelating secondary metabolites secreted by almost all organisms. Beside iron starvation, the ability to produce siderophores depends upon several other factors. Chemical structure of siderophore is very complex with vast structural diversity, thus the principle challenge involves its detection, quantification, purification and characterisation. Metal chelation is its most fascinating attribute. This metal chelation property is now forming the basis of its application as molecular markers, siderotyping tool for taxonomic clarification, biosensors and bioremediation agents. This has led researchers to develop and continuously modify previous techniques in order to provide accurate and reproducible methods of studying siderophores. Knowledge obtained via computational approaches provides a new horizon in the field of siderophore biosynthetic gene clusters and their interaction with various proteins/peptides. This review illustrates various techniques, bioinformatics tools and databases employed in siderophores' studies, the principle of analytical methods and their recent applications.


Assuntos
Ferro/metabolismo , Sideróforos/genética , Sideróforos/metabolismo , Biodegradação Ambiental , Técnicas Biossensoriais , Biologia Computacional , Estrutura Molecular , Metabolismo Secundário , Sideróforos/química
6.
Artigo em Inglês | MEDLINE | ID: mdl-28085556

RESUMO

An appreciation of comparative microbial survival is most easily done while evaluating their adaptive strategies during stress. In the present experiment, antioxidative and whole cell proteome variations based on spectrophotometric analysis and SDS-PAGE and 2-dimensional gel electrophoresis have been analysed among salt-tolerant and salt-sensitive Frankia strains. This is the first report of proteomic basis underlying salt tolerance in these newly isolated Frankia strains from Hippophae salicifolia D. Don. Salt-tolerant strain HsIi10 shows higher increment in the contents of superoxide dismutase, catalase and ascorbate peroxidase as compared to salt-sensitive strain HsIi8. Differential 2-DGE profile has revealed differential profiles for salt-tolerant and salt-sensitive strains. Proteomic confirmation of salt tolerance in the strains with inbuilt efficiency of thriving in nitrogen-deficient locales is a definite advantage for these microbes. This would be equally beneficial for improvement of soil nitrogen status. Efficient protein regulation in HsIi10 suggests further exploration for its potential use as biofertilizer in saline soils.


Assuntos
Antioxidantes/metabolismo , Frankia/metabolismo , Estresse Oxidativo , Proteoma/análise , Tolerância ao Sal , Estresse Fisiológico , Catalase/metabolismo , Frankia/química , Nitrogênio/metabolismo , Proteômica , Cloreto de Sódio/metabolismo
7.
Gen Comp Endocrinol ; 220: 41-5, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25172152

RESUMO

Less is known about genetic basis of photoperiodic regulation of reproductive cycle in subtropical birds. This study measured the expression levels of DIO2, DIO3, GnRH, and GnIH genes in Indian weaver birds subjected to short days (8h light:16h darkness, 8L:16D) and long days (16L:8D) for 48weeks. Whereas small, reproductively inactive testes were maintained under short days, weaver birds underwent testis recrudescence - regression cycle under long days. Relative expression levels of DIO2, DIO3, GnRH and GnIH genes were quantified by the real-time PCR (qPCR) in hypothalamus of birds (n=4) sampled at the beginning of the experiments, and after 10 and 48weeks of short and long day exposures. These sample times represented photosensitive unstimulated (day 0), and under long days the recrudescence (photostimulated, after 10weeks) and regression (photorefractory, after 48weeks) testicular phases. Birds under short days served as controls. The expression pattern of these genes corresponded with testicular phases. High and low GnRH and DIO2 levels were found in birds with large and small testes, respectively. By-and-large the converse was true for GnIH and DIO3 expression levels. Thus, after 10weeks of exposure, there was a significant difference in the mRNA levels between short and long day birds, with small and large testes, respectively. The results also suggest for a possible rapid switching between DIO2 and DIO3 and GnRH and GnIH expressions during testis maturation - regression cycle in Indian weaver birds.


Assuntos
Reprodução/fisiologia , Aves Canoras/fisiologia , Animais , Ritmo Circadiano/fisiologia , Fotoperíodo
8.
J Circadian Rhythms ; 13: 5, 2015 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-27103931

RESUMO

BACKGROUND: Daily feeding and locomotion are interrelated behaviours. The time spent in feeding and rate of food intake depends on food availability. In low food condition, the birds would show intense movement (locomotion) for a longer time throughout the day however during abundant food supply they may chose higher activity and food intake in the morning and evening only. In the present study we hypothesized that in Spotted Munia (Lonchura punctulata), intermittent food availability during day would reallocate their interrelated behaviors, the feeding (food intake) and locomotor activity patterns. METHODS: Two groups of birds (N = 6 each) were kept individually in activity cages under 12L:12D. Group 1 (Control; C) had ad libitum food but group 2 (Treatment; T) had food for 6 hours only (2 h presence followed by 2 h absence; 2P:2A) during 12 hour light period. In the first week, group 2 received food with 'lights on' (TI; ZT 0-2, 4-6 and 8-10; where ZT 0= zeitgeber time 0, time of lights ON). In the following week, the food was given 2 hours after 'lights on' (TII; ZT 2-4, 6-8, 10-12). The food intake and locomotor activity under each condition were observed. RESULTS: The results showed that locomotor activity was induced during food deprivation and suppressed during food availability. Also the food deprivation led to increased food intake. CONCLUSION: Our results suggest that intermittent food availability/deprivation reallocates the locomotor activity and food intake in Spotted Munia.

9.
J Basic Microbiol ; 55(8): 1013-20, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25871924

RESUMO

16S rRNA and nifD-nifK sequences were used to study the molecular phylogeny and evolutionary genetics of Frankia strains isolated from Hippöphae salicifolia D. Don growing at different altitudes (ecologically classified as riverside and hillside isolates) of the Eastern Himalayan region of North Sikkim, India. Genetic information for the small subunit rRNA (16S rRNA) revealed that the riverside Frankia isolates markedly differed from the hillside isolates suggesting that the riverside isolates are genetically compact. Further, for enhanced resolutions, the partial sequence of nifD (3' end), nifK (5' end) and nifD-K IGS region have been investigated. The sequences obtained, failed to separate riverside isolates and hillside isolates, thus suggesting a possible role of genetic transfer events either from hillside to riverside or vice versa. The evolutionary genetic analyses using evogenomic extrapolations of gene sequence data obtained from 16S rRNA and nifD-K provided differing equations with the pace of evolution being more appropriately, intermediate. Values of recombination frequency (R), nucleotide diversity per site (Pi), and DNA divergence estimates supported the existence of an intermixed zone where spatial isolations occurred in sync with the temporal estimates. J. Basic Microbiol. 2015, 54, 1-9.


Assuntos
Evolução Molecular , Frankia/genética , Filogenia , RNA Ribossômico 16S/genética , DNA Intergênico , Frankia/classificação , Frankia/crescimento & desenvolvimento , Genes Bacterianos , Genes de RNAr , Hippophae/microbiologia , Índia , Nitrogenase/genética , Reação em Cadeia da Polimerase , Nódulos Radiculares de Plantas/microbiologia , Análise de Sequência de DNA
10.
Indian J Exp Biol ; 52(4): 352-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24772938

RESUMO

Effect of salinity (0, 50, 100, 250, 500 and 750 mM NaCI) was observed on some important physiological parameters of nitrogen metabolism such as nitrate uptake, intracellular and extracellular ammonium status and activities of nitrogenase, nitrate reductase, nitrite reductase and glutamine synthetase among Frankia strains differing in their salt tolerance capacity. Nitrogenase activity closely followed the growth pattern with regular decline on NaCI supplementation. All the other enzymes showed optimum activity at 100 mM and declined further. Co-regulation of the nitrate uptake system and sequential enzyme activities plays a crucial role in governing the nitrogen status of strains during salt stress. HsIil0 experiencing minimum decline in enzyme activities and best possible nitrogen regulation under NaC1 replete condition showed adequate nutritional management. Among all the strains, HsIil0 proved to be salt tolerant on account of above features while the salt sensitive strain HsIi8 lacked the ability to regulate various steps of nitrogen metabolism during salinity, and thus Frankia strain HsIil0 can potentially serve as a potential biofertilizer in the saline soil.


Assuntos
Frankia/metabolismo , Nitrogênio/metabolismo , Tolerância ao Sal , Amônia/metabolismo , Frankia/enzimologia , Glutamato-Amônia Ligase/metabolismo , Nitratos/metabolismo , Nitrogenase/metabolismo , Salinidade , Cloreto de Sódio/metabolismo
11.
Chronobiol Int ; 41(1): 105-126, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38108138

RESUMO

Biological clocks regulate the behavior and physiology of animals by tracking the local time using diverse time cues. Social cues are relevant in studying the behavior of gregarious animals, but these cues have not been widely studied in birds. Temporal information for circadian timekeeping is socially communicated through visual, physical, olfactory, and auditory means. We examined the efficacy of pulsatile social interactions on locomotor activity and its associated characteristics such as distribution profile of rest and activity, total counts, activity duration, phase shift in activity onset, and circadian periodicity in spotted munia. Besides, we analyzed the effect of such social interactions on their body mass. Spotted munia exhibited phase shift in the onset of activity when subjected to social isolation, but these cues could not affect their circadian periodicity. In Pair as well as in Group, social isolation led to increased activity and activity duration, and decreased body mass in guests relative to the host bird. Our results suggest that the circadian rhythm of locomotor activity in spotted munia is quite sensitive to socialization and isolation, and isolation is detrimental for the birds. Consistent with these observations, the decline in body mass revealed the physiological consequences of social isolation on spotted munia.


Assuntos
Aves , Ritmo Circadiano , Animais , Ritmo Circadiano/fisiologia , Aves/fisiologia
12.
Indian J Otolaryngol Head Neck Surg ; 76(2): 1575-1579, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38566721

RESUMO

Sense of smell is a vital perception in mammals. Temporary loss of smell is the main neurological symptom and one of the earliest and most commonly reported indicators of COVID-19. A observational hospital based analytical study carried out at a tertiary care centre for a period of 22 months from January 2021 to October 2022. All the patients were subjected to sniffin stick test and all the data were noted, tabulated and compared to know the correlation of olfactory sensitivity to different parameters. Males were affected with hyposmia slightly more than females. There was not much difference in the olfactory sensitivity in various phases of uterine cycle. Olfactory sensitivity had a negative correlation with serum oestrogen and serum progesterone levels, which was significant. Mean olfactory sensitivity of males for different odours were slightly higher than females. BMI has a negative correlation with olfactory sensitivity in males as well as females, which was significant.

13.
Chemistry ; 19(52): 17720-32, 2013 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-24327548

RESUMO

N-Glycoprotein linkage region constituents, 2-acetamido-2-deoxy-ß-D-glucopyranose (GlcNAc) and asparagine (Asn) are conserved among all the eukaryotes. To gain a better understanding for nature's choice of GlcNAcßAsn as linkage region constituents and inter- and intramolecular carbohydrate-protein interactions, a detailed systemic structural study of the linkage region conformation is essential. Earlier crystallographic studies of several N-(ß-glycopyranosyl)alkanamides showed that N-glycosidic torsion, φN , is influenced to a larger extent by structural variation in the sugar part than that of the aglycon moiety. To explore the effect of the bioisosteric replacement of a carboxamide group by a sulfonamide moiety on the N-glycosidic torsions as well as on molecular assembly, several glycosyl methanesulfonamides and glycosyl chloromethanesulfonamides were synthesized as analogues of the N-glycoprotein linkage region, and crystal structures of seven of these compounds have been solved. A comparative analysis of this series of crystal structures as well as with those of the corresponding alkanamido derivatives revealed that N-glycosidic torsion, φN, does not alter significantly. Methanesulfonamido and chloromethanesulfonamido derivatives of GlcNAc display a different aglycon conformation compared to other sulfonamido analogues. This may be due to the cumulative effect of the direct hydrogen bonding between N1 and O1' and C-H···O interactions of the aglycon chain, revealing the uniqueness of the GlcNAc as the linkage sugar.


Assuntos
Glicoproteínas/química , Sulfonamidas/química , Cristalografia por Raios X , Ligação de Hidrogênio , Conformação Molecular
14.
Glycoconj J ; 30(8): 769-80, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23760535

RESUMO

The ß-glucosyl linkage to the guanidine group of arginine (Arg) is found in amylogenin, a glycoprotein from sweet corn. Such a linkage is formed by a rare N-glycosylation of proteins. Synthesis of analogs of the unusual N-glycosidic linkage (GlcßArg) with an acetamido or triazole spacer between the glycosyl residue and the guanidine moiety was accomplished by the reaction of fully acetylated sugar unit containing a free amino group with bis-Boc-thiourea. Synthesis of N-glucosylarginine with an amido linker was also achieved during the present study. This methodology was also extended to the synthesis of cationic glucolipid.


Assuntos
Arginina/análogos & derivados , Carboidratos/síntese química , Glucosídeos/síntese química , Acetamidas/síntese química , Arginina/síntese química , Guanidina/síntese química , Triazóis/síntese química
15.
J Basic Microbiol ; 53(2): 163-74, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22733696

RESUMO

The mechanism(s) underlying differential salt sensitivity/tolerance were investigated in the terms of altered morphological and physiological responses against salinity such as growth, electrolyte leakage, Na⁺ uptake, efflux, accumulation and intracellular concentrations of macronutrients among the Frankia strains newly isolated from Hippöphae salicifolia D. Don. Growth was minimally reduced at 500 and 250 mM NaCl respectively in HsIi10 and rest of the strains (HsIi2, HsIi8, HsIi9) which proved that 500 and 250 mM NaCl are the critical concentrations for the respective strains. The differences in the sodium influx/efflux rate was responsible for the differential amount of remaining sodium among the frankial strains and might be one of the primary determinants for the reestablishment of macronutrients (Mg²âº, Ca²âº and K⁺) during salinity. Secondly, the interactive effect of sodium influx/efflux rate, remaining sodium and intracellular macronutrients (Mg²âº, Ca²âº and K⁺) concentration has been responsible for the extent of membrane damage and growth sustenance of the tolerant/sensitive frankial strains during salinity. HsIi10 showed better co-regulation of various factors and managed to tolerate salt stress up to considerable extent. Therefore, HsIi10 can serve as a potential biofertilizer in the saline soil.


Assuntos
Frankia/efeitos dos fármacos , Frankia/metabolismo , Pressão Osmótica , Tolerância ao Sal , Sódio/metabolismo , Estresse Fisiológico , Frankia/fisiologia , Homeostase , Transporte de Íons , Salinidade
16.
J Biomol Struct Dyn ; 41(7): 2733-2746, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35139756

RESUMO

Iron is an important micronutrient for plant growth and development. In the case of Oryza sativa, iron is made available primarily with the help of iron chelators called phytosiderophores i.e. variants of deoxymugineic acid (DMA). They bind with ferric ions and get internalized through Yellow Stripe Like transporters viz. YSL15 and YSL18. However, due to low amount of secretion of phytosiderophores, rice suffers from iron deficiency. Alternatively, siderophores of plant growth promoting rhizobacteria may support iron uptake and make it available to plants via transporting ferric ions possibly through the same transporters. Present study aims to assess comparative binding of DMA and a xenosiderophore (siderophores used by organisms other than the ones producing them) of rhizobacteria i.e. bacillibactin with Fe3+ ion and subsequent transporters of rice. Protein-protein interaction and gene expression analysis predicts uptake of Fe3+ by YSL15 from the rhizosphere region and further distribution through YSL18 with the help of various predicted functional partners. Docking studies confirm the thermodynamically more favourable structure of bacillibactin-Fe3+ complex than DMA-Fe3+ complex. Molecular modelling of YSL15 and YSL18 was done through ab initio method and their evaluation by Ramachandran plot, ProSA, ERRAT value and verify 3 D score revealed a good quality models. Comparative binding assessment through docking and molecular dynamics simulation suggests better binding energies of YSL transporters with bacillibactin-Fe3+ complex as compared to DMA-Fe3+ complex. The current study suggests possible application of xenosiderophores of PGPR origin in supporting plant growth via iron uptake and distribution in rice.Communicated by Ramaswamy H. Sarma.


Assuntos
Ferro , Oryza , Ferro/metabolismo , Sideróforos/genética , Sideróforos/metabolismo , Oryza/genética , Proteínas de Transporte/metabolismo , Proteínas de Membrana Transportadoras/genética , Íons/metabolismo
17.
J Biomol Struct Dyn ; 41(22): 12714-12733, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36762696

RESUMO

Microorganisms produce non-ribosomal peptides called siderophores for the purpose of iron acquisition. Mammalian immune system is well-known for producing small secretory proteins called lipocalins upon bacterial infection. These proteins sequester siderophores produced by invading bacterial pathogens rendering them unable to acquire iron from the host. However, this is not their sole function. In addition to transferrin and lactoferrin, lipocalins are also known to transport siderophore-bound iron to the host cells. While binding of bacterial siderophores with human lipocalin is well studied, binding of the fungal counterpart is still not confirmed and fully understood. Apart from pathogen-affected cells, developing cancerous cells also show varying expression level of different proteins including those involved in iron transport. The possibility of exogenous fungal siderophore-mediated iron transport via lipocalin and its receptor in mammalian cells has not yet been explored much. In present investigation we have checked differential expression of human lipocalin, LCN2 in hepatocellular carcinoma cell lines HepG2 as well as its normal counterpart WRL-68 and computationally determined the feasibility of LCN2 binding with fungal siderophore. Further in case of a stable complex being formed, whether this complex has the ability to transport iron through its specific receptor was assessed. Also, we have tried to explore possible mechanism of fungal-siderophore mediated oxidative stress leading to significant cell death in cancerous cells. This study will thus be useful towards finding a new way of treating hepatocellular carcinoma via inducing siderophore-mediated cell death in cancerous cells.Communicated by Ramaswamy H. Sarma.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Humanos , Sideróforos/química , Sideróforos/metabolismo , Ferro/química , Lipocalina-2/metabolismo , Lipocalinas/metabolismo , Bactérias/química , Linhagem Celular , Morte Celular , Estresse Oxidativo , Mamíferos/metabolismo
18.
Biol Trace Elem Res ; 201(7): 3300-3310, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36192614

RESUMO

Tumour illness and its resistance against existing anticancer therapies pose a serious health concern globally despite the progressive advancement of therapeutic options. The prevailing treatment of HCC using numerous antitumor agents has inflated long-lived complete remissions, but a percentage of individuals still die due to disease recurrence, indicating a need for further exploration of possible anti-tumour regimes. We aim to boost the effectiveness of the HCC treatment by conducting current investigations evaluating the effect of arsenic trioxide (ATO) with different herbal compounds like quercetin and aloe-emodin against liver tumour via inhibition of telomerase, a pro-cancer enzyme. The anticancer activity of ATO with herbal compounds was investigated in human control liver cell line (Wrl-68) and cancer liver cell line (HepG2) at different time intervals. Viability and cytotoxicity in response to combinatorial drugs were assessed in vitro by trypan blue dye exclusion assay and MTT and WST assay. Apoptosis was analysed by annexin V/PI assay, and the expression of telomerase and apoptosis-regulating proteins was evaluated by immunoblotting and qRT-PCR. Arsenic trioxide in combination with quercetin and aloe-emodin reduced cell viability in cancerous cells compared to normal cells by inducing apoptosis, downregulating telomerase and Bcl-2 (anti-apoptotic protein) and upregulating the expression of Bax (pro-apoptotic protein). ATO exhibited significant anticancer effects due to the synergistic effects of quercetin and aloe-emodin in liver tumour cells. The current study data collectively suggest that a successful inhibition of cancer growth by the combination of ATO and tested herbal medicines against liver tumour growth is via the inhibition of telomerase activity.


Assuntos
Antineoplásicos , Arsênio , Arsenicais , Carcinoma Hepatocelular , Emodina , Neoplasias Hepáticas , Telomerase , Humanos , Trióxido de Arsênio/farmacologia , Arsênio/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Telomerase/metabolismo , Telomerase/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Arsenicais/farmacologia , Óxidos/farmacologia , Óxidos/metabolismo , Emodina/farmacologia , Emodina/uso terapêutico , Quercetina/farmacologia , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Apoptose , Proliferação de Células
19.
Indian J Otolaryngol Head Neck Surg ; 75(Suppl 1): 424-428, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36777928

RESUMO

SARS-CoV-2 virus could damage the hearing by several mechanisms, it could damage the auditory centre in the temporal lobe and direct peripheral injury to the sensory cells of the cochlear due to neurotropism of the virus. A Prospective hospital-based observational study was carried out at a tertiary care centre for a period of 22 months from January 2021 to October 2022. A total of 100 patients were selected according to inclusion criteria and exclusion criteria. Pure-tone audiometry (PTA) was done as a screening test; patients were followed up till 6 months. Among those patients who had hearing loss, repeat audiological profile (PTA) was done after 1 month, 13(65%) patients were found to have normal hearing. After 3 months, repeat PTA was done, 18 patients (90%) found to have normal hearing and the remaining 2 patients followed up till 6 months and again PTA was done where only 1 patient continued to have sensorineural hearing loss.

20.
Indian J Otolaryngol Head Neck Surg ; 75(4): 3565-3574, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37974819

RESUMO

Aim & objectives-To assess and compare the nasal obstruction in patients before and after undergoing FESS using Visual analogue scale, Rhinomanometry and Diagnostic nasal endoscopy. Introduction- Chronic Rhinosinusitis with, or without nasal polyps can lead to nasal obstruction. Patients refractory to medical treatment undergo Functional endoscopic sinus surgery (FESS). FESS has been shown to improve subjective quality of life outcomes and objective endoscopic improvement. Material & methods- A prospective study conducted in the department of Ear, Nose & Throat, of a tertiary care medical college and associated Hospital between January 2021 and October 2022. Subjective and objective assessment of nasal obstruction was done using Visual analogue scale, Rhinomanometry and Diagnostic nasal endoscopy before and after surgery at 1st, 3rd and 6th month. Results- Post FESS, there was a significant improvement in nasal obstruction on Visual analogue scale, sinuses were healthy and drainage was adequate on Diagnostic nasal endoscopy, statistically significant (P < 0.05) decrease in nasal resistance was seen on Rhinomanometry. Conclusion- A good subjective outcome on Visual analogue scale and a good objective outcome on Diagnostic nasal endoscopy and Rhinomanometry can be obtained with FESS in patients with Chronic Rhinosinusitis.

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