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1.
J Med Virol ; 96(2): e29478, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38377063

RESUMEN

Choroidal neovascularization (CNV) is a serious condition that affects the retina, causing partial or complete blindness in people of different ages. While CNV is a common occurrence in various chorioretinopathies, research on its occurrence in neonates is limited. Human cytomegalovirus (HCMV) is a significant health threat to neonates, with a strong association with retinal angiogenesis. However, there has been limited investigation into HCMV-associated CNV progression. In this article, we extensively studied the expression of different inflammatory cytokines and chemokines during latent HCMV-associated retinal neovascularization. Our research found that HCMV-induced CNV progression was significantly prominent in the presence of AT2R-dependent angiogenesis (p < 0.001), whereas in the absence of HCMV, AT1R-dependent CCL-5-mediated angiogenesis was documented. We also observed significant increases in CCL-19, CCL-21 chemokine responses, followed by CCR-7 chemokine receptor activation (p < 0.001) in HCMV-induced CNV patients compared to HCMV non-induced CNV groups. Furthermore, significant changes in predictive chemokine markers of HCMV-induced CNV were positively correlated with HCMV viremia. These immunological alterations ultimately lead to the switching of NFκB canonical and noncanonical pathways, respectively, in HCMV-induced neonatal CNV and HCMV non-induced CNV. This clinical observation presents a novel hypothesis that ocular HCMV latency poses a noteworthy risk factor for the progression of retinal neovascularization through a distinctive immunological signaling pathway. The current study represents the first of its kind to report on this association, which may have significant implications for the clinical management of patients with ocular HCMV.


Asunto(s)
Neovascularización Coroidal , Infecciones por Citomegalovirus , Neovascularización Retiniana , Recién Nacido , Humanos , Neovascularización Retiniana/metabolismo , Centros de Atención Terciaria , Neovascularización Coroidal/metabolismo , Retina , Infecciones por Citomegalovirus/complicaciones , Citomegalovirus , Transducción de Señal , Quimiocinas/metabolismo
2.
Phytother Res ; 38(2): 592-619, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37929761

RESUMEN

Sterols, including ß-sitosterol, are essential components of cellular membranes in both plant and animal cells. Despite being a major phytosterol in various plant materials, comprehensive scientific knowledge regarding the properties of ß-sitosterol and its potential applications is essential for scholarly pursuits and utilization purposes. ß-sitosterol shares similar chemical characteristics with cholesterol and exhibits several pharmacological activities without major toxicity. This study aims to bridge the gap between phytochemistry and current pharmacological evidence of ß-sitosterol, focusing on its anticancer activity and other biomedical properties. The goal is to provide a comprehensive understanding of ß-sitosterol's potential for future translational approaches. A thorough examination of the literature was conducted to gather relevant information on the biological properties of ß-sitosterol, particularly its anticancer therapeutic potential. Various databases were searched, including PubMed/MedLine, Scopus, Google Scholar, and Web of Science using appropriate keywords. Studies investigating the effects of ß-sitosterol on different types of cancer were analyzed, focusing on mechanisms of action, pharmacological screening, and chemosensitizing properties. Modern pharmacological screening studies have revealed the potential anticancer therapeutic properties of ß-sitosterol against various types of cancer, including leukemia, lung, stomach, breast, colon, ovarian, and prostate cancer. ß-sitosterol has demonstrated chemosensitizing effects on cancer cells, interfering with multiple cell signaling pathways involved in proliferation, cell cycle arrest, apoptosis, survival, metastasis invasion, angiogenesis, and inflammation. Structural derivatives of ß-sitosterol have also shown anti-cancer effects. However, research in the field of drug delivery and the detailed mode of action of ß-sitosterol-mediated anticancer activities remains limited. ß-sitosterol, as a non-toxic compound with significant pharmacological potential, exhibits promising anticancer effects against various cancer types. Despite being relatively less potent than conventional cancer chemotherapeutics, ß-sitosterol holds potential as a safe and effective nutraceutical against cancer. Further comprehensive studies are recommended to explore the biological properties of ß-sitosterol, including its mode of action, and develop novel formulations for its potential use in cancer treatment. This review provides a foundation for future investigations and highlights the need for further research on ß-sitosterol as a potent superfood in combating cancer.


Asunto(s)
Leucemia , Fitosteroles , Neoplasias de la Próstata , Humanos , Masculino , Animales , Extractos Vegetales/farmacología , Sitoesteroles/farmacología , Sitoesteroles/uso terapéutico , Fitoquímicos/farmacología , Fitoquímicos/uso terapéutico , Etnofarmacología
3.
Physiol Mol Biol Plants ; 29(10): 1591-1603, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38076773

RESUMEN

The present study evaluates the alleviation of polyethylene glycol (PEG) mediated osmotic stress by exogenous spermine (SP) application on seeds of Lens culinaris. Seeds were soaked overnight with SP (0.05 M) and PEG (10%) separately. Third set was prepared by combined treatment with SP (0.05 M) and PEG (10%). Further, various physiological parameters, defense enzymes, phenol, flavonoid, nitric oxide (NO), proline content, chromosomal abnormality studies etc. was conducted after 5 days of incubation. PEG application significantly hampered the seed germination, root length, shoot length, relative water content and vigour index. Application of PEG induced electrolytic leakage in root cells. PEG application also significantly reduced the activities of different defense parameters viz. peroxidase, polyphenol oxidase, phenylalanine ammonia lyase and ß-1,3 glucanase, total phenol and flavonoid accumulation over control. Reactive oxygen species, lipid peroxidation, cell death was found significantly high in PEG treated sets. However, NO level has been significantly decreased by PEG treatment. Cytological studies showed reduced mitotic index and highest abnormalities under osmotic stress. Contrary to that, application of SP either alone or in combination with PEG showed improved responses of aforesaid defense parameters compared to control and solely PEG treated sets. Interestingly, cytological abnormalities were also reduced in SP treated roots. Overall, these results suggests that SP application on seeds reduced the PEG induced damage and intricately improved the defense mechanisms which might help to fight against oxidative stress.

4.
Entropy (Basel) ; 24(4)2022 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-35455126

RESUMEN

The statistical behaviours of different entropy generation mechanisms in the head-on interaction of turbulent premixed flames with a chemically inert wall within turbulent boundary layers have been analysed using Direct Numerical Simulation data. The entropy generation characteristics in the case of head-on premixed flame interaction with an isothermal wall is compared to that for an adiabatic wall. It has been found that entropy generation due to chemical reaction, thermal diffusion and molecular mixing remain comparable when the flame is away from the wall for both wall boundary conditions. However, the wall boundary condition affects the entropy generation during flame-wall interaction. In the case of isothermal wall, the entropy generation due to chemical reaction vanishes because of flame quenching and the entropy generation due to thermal diffusion becomes the leading entropy generator at the wall. By contrast, the entropy generation due to thermal diffusion and molecular mixing decrease at the adiabatic wall because of the vanishing wall-normal components of the gradients of temperature and species mass/mole fractions. These differences have significant effects on the overall entropy generation rate during flame-wall interaction, which suggest that combustor wall cooling needs to be optimized from the point of view of structural integrity and thermodynamic irreversibility.

5.
Plant Cell Rep ; 40(8): 1415-1427, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34109470

RESUMEN

KEY MESSAGE: Foliar application of SA cross-talks and induce endogenous nitric oxide and reactive oxygen species to improve innate immunity and vigor of tomato plant against Fusarium oxysporum stress. The present investigation was aimed to demonstrate the efficacy of salicylic acid (SA), as a powerful elicitor or plant growth regulator (PGR) and its cross-talk with nitric oxide (NO) in tomato against the biotic stress caused by wilt pathogen, Fusarium oxysporum f. sp. lycopersici. Different defense-related enzymes and gene expression, phenol, flavonoid, and phenolic acid content along with NO generation and other physiological characters have been estimated after foliar application of SA. Total chlorophyll content was steadily maintained and the amount of death of cells was negligible after 72 h of SA treatment. Significant reduction of disease incidence was also recorded in SA treated sets. Simultaneously, NO generation was drastically improved at this stage, which has been justified by both spectrophotometrically and microscopically. A direct correlation between reactive oxygen species (ROS) generation and NO has been established. Production of defense enzymes, gene expressions, different phenolic acids was positively influenced by SA treatment. However, tomato plants treated with SA along with NO synthase (NOS) inhibitor or NO scavenger significantly reduce all those parameters tested. On the other hand, NO donor-treated plants showed the same inductive effect like SA. Furthermore, SA treated seeds of tomato also showed improved physiological parameters like higher seedling vigor index, shoot and root length, mean trichome density, etc. It is speculated that the cross-talk between SA and endogenous NO have tremendous ability to improve defense responses and growth of the tomato plant. It can be utilized in future sustainable agriculture for bimodal action.


Asunto(s)
Fusarium/patogenicidad , Óxido Nítrico/metabolismo , Ácido Salicílico/metabolismo , Solanum lycopersicum/inmunología , Solanum lycopersicum/microbiología , Muerte Celular/efectos de los fármacos , Enzimas/metabolismo , Flavonoides/análisis , Flavonoides/metabolismo , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Interacciones Huésped-Patógeno/fisiología , Lignina/metabolismo , Solanum lycopersicum/metabolismo , NG-Nitroarginina Metil Éster/farmacología , Fenoles/análisis , Fenoles/metabolismo , Células Vegetales/efectos de los fármacos , Células Vegetales/microbiología , Enfermedades de las Plantas/inmunología , Enfermedades de las Plantas/microbiología , Inmunidad de la Planta , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácido Salicílico/farmacología , Plantones/efectos de los fármacos , Plantones/inmunología , Plantones/microbiología
6.
Pediatr Nephrol ; 35(7): 1257-1266, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32170428

RESUMEN

BACKGROUND: Congenital nephrotic syndrome (CNS) is a rare but serious condition which affects neonates and is caused by monogenic defects of glomerular structural proteins or congenital viral infections. Several reports have established a causal relationship between human cytomegalovirus (HCMV) intrauterine infection and CNS, but thorough study assessing parameters has not yet been done. METHODS: This study aimed to ascertain significant demographic, biochemical, serological, inflammatory and etiological parameters with 12 months follow-up to clinically identify and monitor neonates with HCMV-associated CNS and sought to decipher the phylogenetic nature of infecting strains. Differences between four patient groups (neonates < 4 weeks old) with or without CNS and HCMV infection were compared by unpaired t testing and one-way analysis of variance (ANOVA). Linear regression was performed to assess statistical significance among individual groups. Maximum-likelihood-based phylogenetic analysis was performed with HCMV gH gene sequences to compare clinically isolated and referenced NCBI strains. This was further supported by analysis of effective number of codons (ENc), codon adaptation index (CAI) and mRNA structural variation. RESULTS: Patients with HCMV-associated CNS were found to have significant variations in many studied parameters compared with controls. The majority of clinical strains formed a separate phylogenetic cluster defining them as somewhat distinct from standard reference strains, which was supported by the other analyses. CONCLUSION: This study defined parameters for monitoring cases of HCMV-associated CNS, which suggest the possible existence of a selection force acting and rendering these HCMV strains able to infect selective host tissues and cause specific disease types.


Asunto(s)
Infecciones por Citomegalovirus/congénito , Síndrome Nefrótico/virología , Adulto , Estudios de Casos y Controles , Estudios Transversales , Citomegalovirus/genética , Citomegalovirus/aislamiento & purificación , Infecciones por Citomegalovirus/sangre , Infecciones por Citomegalovirus/complicaciones , ADN Viral/sangre , Femenino , Humanos , Recién Nacido , Masculino , Síndrome Nefrótico/complicaciones , Síndrome Nefrótico/genética
7.
BMC Pediatr ; 19(1): 291, 2019 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-31438890

RESUMEN

BACKGROUND: Cytomegalovirus [CMV] is a causative agent of congenital infection worldwide and often leads to neurological deficits and hearing loss in newborns. Infants born with symptomatic congenital Cytomegalovirus infection [cCMV] are at significant high risk for developing adverse long-term outcomes. In this study, we look into the sequence variability of surface glycoprotein B [gB] encoding region in newborns with symptomatic CMV infection for the first time in Eastern region of India. METHODS: 576 suspected newborns from seropositive mothers were subjected to the study and ELISA was used to confirm CMV infection. Different genotypes and their subtypes were determined using multiplex nested-PCR. Viral load of different glycoprotein B [gB] genotypes was measured using RT-PCR. Sequencing and phylogenetic analysis was then performed using Bayesian interference. RESULTS: The overall frequency of cCMV infection was 18.4%, where 16.0% neonates were symptomatic. Among the different gB genotypes, gB1 had the highest frequency [23.5%] and gB4 showed the lowest occurrence [5.8%]. 23.5% of symptomatic neonates had mixed genotypes of gB, probably indicating matrenal reinfection with CMV strains in Indian population. Significant genotypic clades [gB1-gB2-gB3-gB5] were grouped closely based on gene sequences, but the gB4 sequence was in the outlier region of the phylogenetic tree indicating the genetic polymorphism. CONCLUSION: This is the first study on cCMV genotyping and its phylogenetic analysis from Eastern Indian neonatal population. The study holds importance in the assessment of cCMV seroprevalence in global perspective. gB protein can be used as a potential therapeutic target against CMV infection.


Asunto(s)
Infecciones por Citomegalovirus/congénito , Genotipo , Proteínas del Envoltorio Viral/genética , Secuencia de Bases , Infecciones por Citomegalovirus/complicaciones , Infecciones por Citomegalovirus/epidemiología , Infecciones por Citomegalovirus/genética , Cartilla de ADN/genética , Femenino , Humanos , India/epidemiología , Recién Nacido , Masculino , Reacción en Cadena de la Polimerasa Multiplex , Filogenia , Análisis de Secuencia de ADN
8.
J Occup Environ Hyg ; 16(1): 41-53, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30299217

RESUMEN

Steady-state axisymmetric simulations using the Reynolds-Averaged Navier-Stokes equations have been carried out in order to optimize the performance of a Chemical, Biological, Radiological, and Nuclear (CBRN) canister filter for its use in a powered air-purifying respirator (PAPR). Alterations have been made to the shape of the canister, the spacing of the rear wall of the canister with regard to the carbon filter, and the bracketing between (i) the particulate filter and the carbon bed and (ii) the carbon bed and the canister wall. The pressure drops across the canister and the residence time distribution at the rear of the carbon bed have been analyzed in detail based on an extensive parametric analysis involving the aforementioned variations. It has been demonstrated that the non-uniform porosity profile of the carbon bed resulted in alternating regions of high and low velocity close to the canister wall, providing a possible route for breakthrough. Designs, which included a bracket at the rear of the carbon bed, blocked this route and consequently had a longer minimum mean residence time than those, which did not. It has also been shown that the spacing between the carbon bed and the canister rear wall had a large impact on both residence time and pressure drop. In cases where the carbon backed directly onto the canister rear wall flow in the axial direction from the outside wall toward the canister axis resulted in far greater pressure drop and a reduction in minimum mean residence time within the carbon bed.


Asunto(s)
Filtros de Aire , Diseño de Equipo , Dispositivos de Protección Respiratoria , Carbono/química , Hidrodinámica , Exposición por Inhalación/prevención & control , Modelos Teóricos
9.
Physiol Mol Biol Plants ; 23(3): 581-596, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28878497

RESUMEN

The objective of this study was to investigate the effectiveness of calcium chloride (CaCl2), as potential elicitor, on tomato plants against Fusarium oxysporum f. sp. lycopersici. Foliar application of CaCl2 showed significant reduction of wilt incidence after challenge inoculation. Increased production of defense and antioxidant enzymes was observed in elicitor treated sets over control. Simultaneously, altered amount of phenolic acids were analyzed spectrophotometrically and by using high performance liquid chromatography. Significant induction of defense-related genes expressions was measured by semi-quantitative RT-PCR. Greater lignifications by microscopic analysis were also recorded in elicitor treated plants. Simultaneously, generation of nitric oxide (NO) in elicitor treated plants was confirmed by spectrophotometrically and microscopically by using membrane permeable fluorescent dye. Furthermore, plants treated with potential NO donor and NO modulators showed significant alteration of all those aforesaid defense molecules. Transcript analysis of nitrate reductase and calmodulin gene showed positive correlation with elicitor treatment. Furthermore, CaCl2 treatment showed greater seedling vigor index, mean trichome density etc. The result suggests that CaCl2 have tremendous potential to elicit defense responses as well as plant growth in co-relation with NO, which ultimately leads to resistance against the wilt pathogen.

10.
Physiol Mol Biol Plants ; 22(3): 307-320, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27729717

RESUMEN

Improvement of the host resistance by using hazard free chemical elicitors is emerging as an alternative approach in the field of plant disease management. In our present work, we have screened the efficacy and possible mechanism of abiogenic elicitors like Dipotassium hydrogen orthophosphate (K2HPO4), Oxalic acid (OA), Isonicotinic acid (INA), Salicylic acid (SA), Acetylsalicylate (AS), Arachidonic acid (AA) and Calcium chloride (CaCl2) to stimulate innate immune responses in Lycopersicum esculentum Mill. Excised tomato leaves, treated with elicitors at three different concentrations, were found to stimulate defense and antioxidative enzymes, total phenol and flavonoid content after 24 h of incubation. CaCl2 (0.5 %) followed by INA (2.5 mM) were found most effective in activation of all such defense molecules in tomato leaves. Furthermore, nitric oxide (NO), a key gaseous mediator in plant defense signaling, was also measured after subsequent elicitor application. Higher doses of elicitors showed an elevated level of reactive oxygen species (ROS) generation, enhanced lipid peroxidation rate and proline content, which indicates the extent of abiotic stress generation on the leaves. However, ROS production, lipid peroxidation rate and proline concentration remain significantly reduced as a result of CaCl2 (0.5 %) and INA (2.5 mM) application. A sharp increase of total chlorophyll content was also recorded due to treatment of CaCl2 (0.5 %). These results demonstrate the effects of different abiogenic elicitors to regulate the production of defense molecules. Results also suggest that among all such chemicals, CaCl2 (0.5 %) and INA (2.5 mM) can be used as a potential elicitor in organic farming of tomato.

11.
ScientificWorldJournal ; 2015: 208649, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25729768

RESUMEN

Effect of sublethal heavy metal stress as plant biotic elicitor for triggering innate immunity in tomato plant was investigated. Copper in in vivo condition induced accumulation of defense enzymes like peroxidase (PO), polyphenol oxidase (PPO), phenylalanine ammonia-lyase (PAL), and ß-1,3 glucanase along with higher accumulation of total phenol, antioxidative enzymes (catalase and ascorbate peroxidase), and total chlorophyll content. Furthermore, the treatment also induced nitric oxide (NO) production which was confirmed by realtime visualization of NO burst using a fluorescent probe 4,5-diaminofluorescein diacetate (DAF-2DA) and spectrophotometric analysis. The result suggested that the sublethal dose of heavy metal can induce an array of plant defense responses that lead to the improvement of innate immunity in plants.


Asunto(s)
Inmunidad Innata/efectos de los fármacos , Metales Pesados/toxicidad , Solanum lycopersicum/inmunología , Análisis de Varianza , Ascorbato Peroxidasas/metabolismo , Catalasa/metabolismo , Catecol Oxidasa/inmunología , Clorofila/metabolismo , Fluorescencia , Glucano 1,3-beta-Glucosidasa/inmunología , Solanum lycopersicum/efectos de los fármacos , Peroxidasa/inmunología , Fenoles/metabolismo , Fenilanina Amoníaco-Liasa/inmunología , Espectrofotometría
12.
Sci Rep ; 14(1): 14861, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38937515

RESUMEN

The combustion of hydrogen and carbon-monoxide mixtures, so-called syngas, plays an increasingly important role in the safety context of non-fossil energy generation, more specifically in the risk management of incidents in process engineering plants for ammonia synthesis and in nuclear power plants. In order to characterize and simulate syngas/air combustion on industrially relevant scales, subgrid modelling is required, which is often based on a reaction progress variable. To understand the influence of different fuel compositions, turbulence intensities and flame topologies on different possible definitions of reaction progress variable, detailed chemistry direct numerical simulations data of premixed, lean hydrogen/air and syngas/air flames has been considered. A reaction progress variable based on normalized molecular oxygen mass fraction has been found not to capture the augmentation of the normalized burning rate per unit flame surface area in comparison to the corresponding 1D unstretched premixed flame due to preferential diffusion effects. By contrast, reaction progress variables based on other individual species, such as hydrogen, can capture the augmentation of the rate of burning well, but exhibit a pronounced sensitivity to preferential diffusion effects, especially in response to flame curvatures. However, a reaction progress variable based on the linear combination of the main products can accurately represent the temperature evolution of the flame for different mixtures, turbulence intensities and varying local flame topology, while effectively capturing the augmentation of burning rate due to preferential diffusion effects. However, its tendency to assume values larger than 1.0 in the regions of super-adiabatic temperatures poses challenges for future modeling approaches, whereas the reaction progress variable based on hydrogen mass fraction remains bound between 0.0 and 1.0 despite showing deviations in comparison to corresponding variations obtained from the unstretched laminar flame depending on flame curvature variations.

13.
Viruses ; 16(6)2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38932140

RESUMEN

Background: HCMV causes severe clinical complications in transplant recipients and may lead to graft rejection. Successful renal transplantation heavily relies on the early prevention and diagnosis of CMV infections, followed by prompt prophylactic treatment before transplantation. Despite the majority of renal rejection cases with acute HCMV infections being asymptomatic and occurring one to two years later, the objective of this research was to comprehend the effect of late HCMV infection on renal rejection by examining specific clinical parameters in the Eastern Indian cohort. Method: In this study, 240 patients were studied for five years following transplantation, and their data were collected from the local metropolitan hospital in Eastern India. Both HCMV-positive and -negative post-transplant patients were investigated using the clinical parameters and viral loads for latent infection. Results: Within the studied population, 79 post-transplant patients were found to be HCMV positive. Among them, 13 (16.45%) patients suffered from renal rejection within less than 2 yrs. of transplantation (early rejection) and 22 (27.84%) patients suffered from renal rejection after 2 yrs. from the operation date (late rejection). Assessment of clinical parameters with respect to HCMV infection revealed that in early rejection cases, fever (p-0.035) and urinary tract infection (p-0.017) were prominent, but in late rejection, hematuria (p-0.032), diabetes (p-0.005), and creatinine level changes (p < 0.001) were significant along with urinary tract infection (p-0.047). Conclusions: This study provides valuable insights into monitoring latent CMV infections and highlights the understanding of reducing renal rejection rates and the need for further research in this field.


Asunto(s)
Infecciones por Citomegalovirus , Citomegalovirus , Rechazo de Injerto , Trasplante de Riñón , Humanos , Infecciones por Citomegalovirus/epidemiología , Infecciones por Citomegalovirus/etiología , Trasplante de Riñón/efectos adversos , India/epidemiología , Masculino , Femenino , Adulto , Persona de Mediana Edad , Carga Viral , Estudios de Cohortes , Adulto Joven , Receptores de Trasplantes
14.
Sci Rep ; 14(1): 5525, 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38448459

RESUMEN

Flame self-interaction (FSI) events in Moderate or Intense Low-Oxygen Dilution (MILD) combustion of homogeneous and inhomogeneous mixtures of methane and oxidiser have been analysed using three-dimensional Direct Numerical Simulations (DNS). The simulations have been conducted at the same global equivalence ratio ( ⟨ ϕ ⟩ = 0.8 ) for different levels of O 2 concentration (dilution) and initial turbulence intensities. It has been reported that both homogeneous and inhomogeneous mixture MILD combustion cases exhibit significant occurrences of FSI events, with the peak frequency of FSI events occurring towards the burned gas side in all cases. Moreover, the frequency of FSI events increases with increasing dilution level and turbulence intensity, but the presence of mixture inhomogeneity leads to a reduction in total FSI events. In all cases, the cylindrical FSI topologies (i.e. tunnel formation and tunnel closure) were found to have a higher likelihood of occurrence compared to spherical FSI topologies (i.e. unburned and burned gas pockets). The geometries of FSI topologies were also analysed using the mean and Gaussian curvatures. It has been shown that the inward propagating spherical FSI topologies (i.e. unburned gas pockets) are associated with negative mean curvature, while outward propagating spherical FSI topologies (i.e. burned gas pockets) are associated with positive mean curvature. Moreover, tunnel formation (tunnel closure) FSI topologies predominantly exhibit either elliptic geometries with positive (negative) mean curvature or hyperbolic saddle geometries with negative (positive) mean curvature. It has been shown for the first time in MILD combustion that the mean values of kinematic restoration and dissipation terms in the transport equation of the magnitude of the reaction progress variable conditional upon the reaction progress variable tend to cancel each other in the vicinity of the critical points associated with cylindrical topologies. Thus, the singular contributions in these terms, which are obtained from analytical descriptions in the vicinity of tunnel formation and tunnel closure topologies, do not affect the balance equation of the magnitude of the gradient of the reaction progress variable. Consequently, there is no need for a separate model treatment for singularities in modelling approaches based on the magnitude of the gradient of the reaction progress variable. The FSI events in the reaction dominated and propagating flame regions of MILD combustion have also been analysed for the first time. It has been found that more FSI events occur in the reaction dominated region, particularly towards the burned gas side. However, the majority of spherical FSI topologies are found in the propagating flame region. The findings from this study indicate that turbulence intensity, dilution level and mixture inhomogeneity effects need to be considered in any attempt to extend flame surface-based modelling approaches to MILD combustion.

15.
PLoS One ; 19(4): e0301644, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38573991

RESUMEN

Dengue and chikungunya are co-circulating vector-borne diseases that share a significant number of clinical symptoms. To identify variables to aid physicians in making rapid and effective diagnostic decisions, we performed molecular diagnosis of the chikungunya virus and examined the clinical manifestations of chikungunya cases to identify the prevalence among dengue-negative individuals in Kolkata. Dengue suspected patients' samples were collected during January 2020-December 2021 and Enzyme-linked immunosorbent assay (ELISA) and reverse transcription-polymerase chain reaction (RT-PCR) methods have been performed to confirm the prevalence of chikungunya infection among dengue-negative patients. By performing phylogenetic analysis, comparing clinical classifications, identifying disease aetiology using clinical and laboratory factors, and evaluating the time course of several clinical variables, we have evaluated the clinical manifestations linked to dengue and chikungunya virus infections. Chikungunya infection was found in 15.1% and 6.3% of the 635 dengue-negative patients, as determined by ELISA and RT-PCR, respectively. Arthritis and myalgia were more common in chikungunya-infected patients at the time of hospital admission while conjunctivitis, photosensitivity, arthralgia, Anorexia, fatigue, retro-orbital pain, vomiting, dermatitis, or swollen glands were significantly presented as an overlapping symptom. Although dengue and chikungunya infections have significant clinical overlap, basic clinical and laboratory criteria can predict these diseases at presentation for proper management. Effective management enables doctors to treat and care for patients properly and contributes to the development of control measures for these infections in a medical setting.


Asunto(s)
Fiebre Chikungunya , Virus Chikungunya , Dengue , Humanos , Fiebre Chikungunya/diagnóstico , Fiebre Chikungunya/epidemiología , Filogenia , Dengue/diagnóstico , Dengue/epidemiología , Anticuerpos Antivirales , India/epidemiología
16.
Plant Physiol Biochem ; 206: 108272, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38100892

RESUMEN

Lipid peroxidation (LPO) is a complex process that, depending on the context, can either result in oxidative injury or promote redox homeostasis. LPO is a series of reactions in which polyunsaturated fatty acids are attacked by free radicals that result in the synthesis of lipid peroxides. LPO can alter membrane fluidity and operation and produce secondary products that amplify oxidative stress. LPO can activate cellular signaling pathways that promote antioxidant defense mechanisms that provide oxidative stress protection by elevating antioxidant enzyme action potentials. Enzymatic and nonenzymatic mechanisms tightly regulate LPO to prevent excessive LPO and its adverse consequences. This article emphasizes the dual nature of LPO as a mechanism that can both damage cells and regulate redox homeostasis. In addition, it also highlights the major enzymatic and nonenzymatic mechanisms that tightly regulate LPO to prevent excessive oxidative damage. More importantly, it emphasizes the importance of understanding the cellular and biochemical complexity of LPO for developing strategies targeting this process for efficient management of plant stress.


Asunto(s)
Antioxidantes , Estrés Oxidativo , Peroxidación de Lípido/fisiología , Antioxidantes/metabolismo , Oxidación-Reducción , Plantas/metabolismo , Homeostasis , Especies Reactivas de Oxígeno/metabolismo
17.
Eur J Med Res ; 29(1): 269, 2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38704602

RESUMEN

HHT has emerged as a notable compound in the realm of cancer treatment, particularly for hematological malignancies. Its multifaceted pharmacological properties extend beyond traditional applications, warranting an extensive review of its mechanisms and efficacy. This review aims to synthesize comprehensive insights into the efficacy of HHT in treating hematological malignancies, diverse cancers, and other biomedical applications. It focuses on elucidating the molecular mechanisms, therapeutic potential, and broader applications of HHT. A comprehensive search for peer-reviewed papers was conducted across various academic databases, including ScienceDirect, Web of Science, Scopus, American Chemical Society, Google Scholar, PubMed/MedLine, and Wiley. The review highlights HHT's diverse mechanisms of action, ranging from its role in leukemia treatment to its emerging applications in managing other cancers and various biomedical conditions. It underscores HHT's influence on cellular processes, its efficacy in clinical settings, and its potential to alter pathological pathways. HHT demonstrates significant promise in treating various hematological malignancies and cancers, offering a multifaceted approach to disease management. Its ability to impact various physiological pathways opens new avenues for therapeutic applications. This review provides a consolidated foundation for future research and clinical applications of HHT in diverse medical fields.


Asunto(s)
Neoplasias Hematológicas , Homoharringtonina , Humanos , Neoplasias Hematológicas/tratamiento farmacológico , Homoharringtonina/uso terapéutico , Homoharringtonina/farmacología , Neoplasias/tratamiento farmacológico , Animales
18.
Physiol Mol Biol Plants ; 19(1): 117-25, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24381443

RESUMEN

Withania somnifera (L.) Dunal, is an important medicinal plant being the source of extremely important compounds like withanolides and withaferin. Influence of different plant growth regulators (PGRs) were evaluated for induction of callus, callus mediated regeneration and production of secondary metabolites in them. Explants for callusing were collected from plants grown in vitro and maximum callusing (98 %) was obtained on MS medium supplemented with a combination of 2,4-dichlorophenoxy acetic acid (2,4-D) (0.5 mg l(-1)) and kinetin (KN) (0.2 mg l(-1)). Among different types of calli, best shoot regeneration was observed on green, compact calli produced on MS medium with a combination of 6-benzylamino purine (BAP) and indole butyric acid (IBA). MS medium supplemented with BAP (2 mg l(-1)) showed highest frequency (98 %) of shoot bud regeneration. The micro-shoots were efficiently rooted on MS media supplemented with 0.5 mg l(-1) IBA. Rooted plants were transferred to soil-vermi-compost (1:3; w/w) medium in greenhouse for acclimatization. Presence of withanolide A and withaferin A in calli was validated through high performance thin layer chromatography (HPTLC). It was interesting to observe that the PGRs showed significant influence on the secondary metabolites production in callus and 2,4-D having the least effect. Histological studies revealed the origin of shoot tip in the callus during regeneration.

19.
Sci Rep ; 13(1): 837, 2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36646821

RESUMEN

The reactive Richtmyer-Meshkov instability (RMI) exhibits strong wrinkling of a reactive flame front after an interaction with a shock wave. High levels of deformation and wrinkling can cause the flame surface to intersect with itself, leading to the events of flame self interactions (FSI). As FSI can have a significant influence on the development and topology of the flame surface, it should be considered an important factor affecting the burning characteristics of the flame. The topological structure and statistics of FSI are analyzed using data from high-fidelity simulations of a planar shock wave interacting with a statistically planar hydrogen/air flame for stoichiometric, lean and nonreactive gas mixtures. FSI events are detected by searching for critical points in the field of the reaction progress variable c and divided into the following topological categories: burned gas mixture pocket (BP), unburned gas mixture pocket (UP), tunnel formation (TF) and tunnel closure (TC). It is found that reactivity and flame thickness are decisive factors, influencing the frequency and topological distribution of the detected FSI events. While in early RMI-stages the FSI is found to be mainly dependent on the flame thickness, later stages are heavily influenced by the reactivity, as high reactivity quickly burns out emerging wrinkled structures (in the stoichiometric case) leading to massively reduced levels of FSI. The findings are further supported by the results from the nonreactive case, which at later stages of the RMI closely resembles the less reactive lean case. Analysis of the topology distribution over time and conditioned over c, reveals further differences between the lean and stoichiometric case, as the strong wrinkling and mixing encountered with the lean case facilitates the build up of many pocket-type and tunnel-type interactions throughout the wrinkled flame front. For the stoichiometric case, mainly tunnel-type and unburned pocket topologies are found in the narrow flame funnels extending into the burned gas.

20.
Heliyon ; 9(1): e12953, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36711264

RESUMEN

Bio-inoculation involves the association of plant with some beneficial microorganisms, and among these microbiotas, those bacteria which can promote plant growth and development are known as Plant Growth Promoting Rhizobacteria (PGPR). It can help a plant directly or indirectly, which includes root development, biological nitrogen (N2) fixation, stress tolerance, cell division and elongation, solubilization of Zinc, Phosphate, Potassium, soil health improvement and many more. PGPR have gained attention as it can be used as biofertilizers and helpful in bioremediation techniques, which in turn can reduce the chemical dependency in agriculture. PGPR mediated plant growth and stress management is developed by the virtue of the interaction of plant and microbial signalling pathways. On the other hand, environmental stresses are something to which a plant is always exposed irrespective of other factors. The present review is all about the better understanding of the convergence strategies of these signalling molecules and the ambiguities of signalling activities occurring in the host due to the interaction with PGPR under environmental stressed conditions.

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