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1.
Plant Cell Physiol ; 64(10): 1124-1138, 2023 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-37498947

RESUMEN

From simple algal forms to the most advanced angiosperms, calcium oxalate (CaOx) crystals (CRs) occur in the majority of taxonomic groups of photosynthetic organisms. Various studies have demonstrated that this biomineralization is not a simple or random event but a genetically regulated coordination between calcium uptake, oxalate (OX) synthesis and, sometimes, environmental stresses. Certainly, the occurrence of CaOx CRs is old; however, questions related to their genesis, biosynthesis, significance and genetics exhibit robust evolution. Moreover, their speculated roles in bulk calcium regulation, heavy metal/OX detoxification, light reflectance and photosynthesis, and protection against grazing and herbivory, besides other characteristics, are gaining much interest. Thus, it is imperative to understand their synthesis and regulation in relation to the ascribed key functions to reconstruct future perspectives in harnessing their potential to achieve nutritious and pest-resistant crops amid anticipated global climatic perturbations. This review critically addresses the basic and evolving concepts of the origin (and recycling), synthesis, significance, regulation and fate vis-à-vis various functional aspects of CaOx CRs in plants (and soil). Overall, insights and conceptual future directions present them as potential biominerals to address future climate-driven issues.


Asunto(s)
Oxalato de Calcio , Calcio , Oxalato de Calcio/química , Calcio/metabolismo , Fotosíntesis/fisiología , Transporte Biológico , Plantas/metabolismo
2.
Sensors (Basel) ; 22(4)2022 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-35214219

RESUMEN

The paradigm of dynamic shared access aims to provide flexible spectrum usage. Recently, Federal Communications Commission (FCC) has proposed a new dynamic spectrum management framework for the sharing of a 3.5 GHz (3550-3700 MHz) federal band, called a citizen broadband radio service (CBRS) band, which is governed by spectrum access system (SAS). It is the responsibility of SAS to manage the set of CBRS-SAS users. The set of users are classified in three tiers: incumbent access (IA) users, primary access license (PAL) users and the general authorized access (GAA) users. In this article, dynamic channel assignment algorithm for PAL and GAA users is designed with the goal of maximizing the transmission rate and minimizing the total cost of GAA users accessing PAL reserved channels. We proposed a new mathematical model based on multi-objective optimization for the selection of PAL operators and idle PAL reserved channels allocation to GAA users considering the diversity of PAL reserved channels' attributes and the diversification of GAA users' business needs. The proposed model is estimated and validated on various performance metrics through extensive simulations and compared with existing algorithms such as Hungarian algorithm, auction algorithm and Gale-Shapley algorithm. The proposed model results indicate that overall transmission rate, net cost and data-rate per unit cost remain the same in comparison to the classical Hungarian method and auction algorithm. However, the improved model solves the resource allocation problem approximately up to four times faster with better load management, which validates the efficiency of our model.

3.
Sensors (Basel) ; 20(7)2020 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-32230988

RESUMEN

The focus of research efforts in cognitive radio networks (CRNs) has primarily remained confined to maximizing the utilization of the discovered resources. However, it is also important to enhance the user satisfaction in CRNs by finding a suitable match between the secondary users and the idle channels available from the primary network while taking into consideration not only the quality of service (QoS) requirements of the secondary users but the quality of the channels as well. In this work, the Gale Shapley matching theory was applied to find the best match, so that the most suitable channels from the available pool were allocated that satisfy the QoS requirements of the secondary users. Before applying matching theory, two objective functions were defined from the secondary user's perspective as well as from the channel's perspective. The objective function of secondary users is the weighted sum of the data rate of the secondary users and the probability of reappearance of the primary user on the channel. Whereas, the objective function of the channel is the maximum utilization of the channel. The weight factors included in the objective functions allow for diverse service classes of secondary users (SUs) or varying channel quality characteristics. The objective functions were used in developing the preference lists for the secondary users and the idle channels. The preference lists were then used by the Gale Shapely matching algorithm to determine the most suitably matched SU-channel pairs. The performance of the proposed scheme was evaluated using Monte-Carlo simulations. The results show significant improvement in the overall satisfaction of the secondary users with the proposed scheme in comparison to other contemporary techniques. Further, the impact of changing the weight factors in the objective functions on the secondary user's satisfaction and channel utilization was also analyzed.

4.
Planta ; 251(1): 15, 2019 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-31776718

RESUMEN

MAIN CONCLUSION: Present review provides a thorough insight on some significant aspects of CHSs over a period of about past three decades with a better outlook for future studies toward comprehending the structural and mechanistic intricacy of this symbolic enzyme. Polyketide synthases (PKSs) form a large family of iteratively acting multifunctional proteins that are involved in the biosynthesis of spectrum of natural products. They exhibit remarkable versatility in the structural configuration and functional organization with an incredible ability to generate different classes of compounds other than the characteristic secondary metabolite constituents. Architecturally, chalcone synthase (CHS) is considered to be the simplest representative of Type III PKSs. The enzyme is pivotal for phenylpropanoid biosynthesis and is also well known for catalyzing the initial step of the flavonoid/isoflavonoid pathway. Being the first Type III enzyme to be discovered, CHS has been subjected to ample investigations which, to a greater extent, have tried to understand its structural complexity and promiscuous functional behavior. In this context, we vehemently tried to collect the fragmented information entirely focussed on this symbolic enzyme from about past three-four decades. The aim of this review is to selectively summarize data on some of the fundamental aspects of CHSs viz, its history and distribution, localization, structure and analogs in non-plant hosts, promoter analyses, and role in defense, with an emphasis on mechanistic studies in different species and vis-à-vis mutation-led changes, and evolutionary significance which has been discussed in detail. The present review gives an insight with a better perspective for the scientific community for future studies devoted towards delimiting the mechanistic and structural basis of polyketide biosynthetic machinery vis-à-vis CHS.


Asunto(s)
Sintasas Poliquetidas/genética , Aciltransferasas/genética , Aciltransferasas/metabolismo , Sintasas Poliquetidas/metabolismo , Regiones Promotoras Genéticas/genética
5.
Plant Mol Biol ; 96(1-2): 197-215, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29270891

RESUMEN

KEY MESSAGE: Comprehensive transcriptome analysis of leaf and root tissues of Nothapodytes nimmoniana unravels several putative pathway genes, transcription factors and CYPs related to camptothecin (CPT) biosynthesis. Additionally, post-transcriptional suppression by artificial microRNA (aMIR) of NnCYP76B6 (geraniol 10-hydroxylase) suggests its role in CPT biosynthesis. Tissue-specific LC-MS/MS analysis revealed the presence of secologanin as the central intermediate of MIA pathway in N. nimmoniana. Nothapodytes nimmoniana is a rich source of potent anticancer drug camptothecin (CPT) whose biosynthetic pathway is unresolved due to the lack of genomic and transcriptomic information. Present investigation entails deep transcriptome analysis of N. nimmoniana which led to identification of putative pathway genes and regulatory components involved in CPT biosynthesis. Using Illumina HiSeq 2500 sequencing platform a total of 31,172,889 (6.23 Gb) and 31,218,626 (6.24 Gb) raw reads were generated from leaf and root wood, respectively. These were assembled de novo into 138,183 unique contigs. Additionally, 16 cytochrome P450 transcripts related to secondary metabolism were also identified. Further, transcriptome data pool presented 1683 putative transcription factors of which transcripts corresponding to WRKY TFs were the most abundant (14.14%). A total of 2741 transcripts were differentially expressed out of which 478 contigs showed downregulation in root wood and 2263 contigs were up-regulated. Further, comparative analyses of 17 genes involved in CPT biosynthetic pathway were validated by qRT-PCR. On basis of intermediates, two distinct seco-iridoid pathways are involved in the biosynthesis of monoterpene indole alkaloids either through multiple isomers of strictosidinic acid or strictosidine. Tissue-specific LC-MS/MS analysis revealed the presence of secologanin as the central intermediate of MIA pathway in N. nimmoniana. Geraniol-10 hydroxylase (NnCYP76B6) an important enzyme in CPT biosynthesis which specifically shunts geraniol into the secologanin pathway was also cloned from the trancriptome resource. In planta transient expression of NnCYP76B6 showed a significant enhancement in mRNA transcript levels coincident with enhanced CPT accumulation. Further, artificial microRNA (aMIR) mediated downregulation of NnCYP76B6 resulted in reduction of mRNA transcript levels as well as CPT content in comparison to control. These empirical results suggest a plausible regulatory role for NnCYP76B6 in CPT biosynthesis and also establish a valuable repository for deciphering various structural, rate limiting and regulatory genes of CPT biosynthetic pathway.


Asunto(s)
Camptotecina/metabolismo , Magnoliopsida/metabolismo , Transcriptoma/genética , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Perfilación de la Expresión Génica , Magnoliopsida/genética , MicroARNs/genética
6.
Phytochem Rev ; 17(3): 573-609, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-32214920

RESUMEN

Rheum australe (Himalayan Rhubarb) is a multipurpose, endemic and endangered medicinal herb of North Western Himalayas. It finds extensive use as a medicinal herb since antiquity in different traditional systems of medicine to cure a wide range of ailments related to the circulatory, digestive, endocrine, respiratory and skeletal systems as well as to treat various infectious diseases. The remedying properties of this plant species are ascribed to a set of diverse bioactive secondary metabolite constituents, particularly anthraquinones (emodin, chrysophanol, physcion, aloe-emodin and rhein) and stilbenoids (piceatannol, resveratrol), besides dietary flavonoids known for their putative health benefits. Recent studies demonstrate the pharmacological efficacy of some of these metabolites and/or their derivatives as lead molecules for the treatment of various human diseases. Present review comprehensively covers the literature available on R. australe from 1980 to early 2018. The review provides up-to-date information available on its botany for easy identification of the plant, and origin and historical perspective detailing its trade and commerce. Distribution, therapeutic potential in relation to traditional uses and pharmacology, phytochemistry and general biosynthesis of major chemical constituents are also discussed. Additionally, efficient and reproducible in vitro propagation studies holding vital significance in preserving the natural germplasm of the plant and for its industrial exploitation have also been highlighted. The review presents a detailed perspective for future studies to conserve and sustainably make use of this endangered plant species at a commercial scale.

7.
East Mediterr Health J ; 24(1): 33-41, 2018 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-29658619

RESUMEN

BACKGROUND: Pakistan lacks data on the prevalence of risk factors for common noncommunicable diseases (NCDs). OBJECTIVES: This study aimed to determine the prevalence of risk factors for NCDs among a population-based sample in Punjab and Sindh provinces, Pakistan. METHODS: This study was conducted in 2013-2014. The NCD risk factors examined were: current daily smoking, eating fewer than 5 servings of fruits/vegetable a day, low physical activity, overweight and obesity. A total of 7 710 households were selected and 1 adult was enrolled from each household. Data were collected using the WHO STEPS instrument (Step 1 and 2), and analysed according to the STEPS statistical plan. RESULTS: The prevalence of tobacco use was 19.7%. The majority of the respondents (96.5%) consumed fewer than 5 servings of fruits/vegetables a day, 41.5% had a low level of physical activity, 26.3% were overweight and 14.9% were obese. The prevalence of stage I and stage II hypertension, including those on medication, was 37% and 15.9% respectively. The prevalence of NCD risk factors differed significantly by sex and occupation (P = 0.0001) but not by age group (P = 0.118), level of education (P = 0.668) and province (P = 0.056). Only 0.6% of the sample had none of the 5 NCD risk factors while 40% had 3-5. CONCLUSION: The high prevalence of NCD risk factors in Punjab and Sindh provinces is of concern. Urgent public health interventions are needed to reduce them, especially in youth and young adults.


Asunto(s)
Enfermedades no Transmisibles/epidemiología , Adolescente , Adulto , Factores de Edad , Anciano , Dieta/estadística & datos numéricos , Ejercicio Físico , Femenino , Encuestas Epidemiológicas , Humanos , Masculino , Persona de Mediana Edad , Sobrepeso/epidemiología , Pakistán/epidemiología , Prevalencia , Características de la Residencia , Factores de Riesgo , Factores Sexuales , Fumar/epidemiología , Factores Socioeconómicos , Adulto Joven
8.
Plant Physiol ; 171(4): 2599-619, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27268960

RESUMEN

Plants effectively defend themselves against biotic and abiotic stresses by synthesizing diverse secondary metabolites, including health-protective flavonoids. These display incredible chemical diversity and ubiquitous occurrence and confer impeccable biological and agricultural applications. Chalcone synthase (CHS), a type III plant polyketide synthase, is critical for flavonoid biosynthesis. It catalyzes acyl-coenzyme A thioesters to synthesize naringenin chalcone through a polyketidic intermediate. The functional divergence among the evolutionarily generated members of a gene family is pivotal in driving the chemical diversity. Against this backdrop, this study was aimed to functionally characterize members of the CHS gene family from Rheum emodi, an endangered and endemic high-altitude medicinal herb of northwestern Himalayas. Two full-length cDNAs (1,179 bp each), ReCHS1 and ReCHS2, encoding unique paralogs were isolated and characterized. Heterologous expression and purification in Escherichia coli, bottom-up proteomic characterization, high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry analysis, and enzyme kinetic studies using five different substrates confirmed their catalytic potential. Phylogenetic analysis revealed the existence of higher synonymous mutations in the intronless divergents of ReCHS. ReCHS2 displayed significant enzymatic efficiency (Vmax/Km) with different substrates. There were significant spatial and altitudinal variations in messenger RNA transcript levels of ReCHSs correlating positively with metabolite accumulation. Furthermore, the elicitations in the form of methyl jasmonate, salicylic acid, ultraviolet B light, and wounding, chosen on the basis of identified cis-regulatory promoter elements, presented considerable differences in the transcript profiles of ReCHSs. Taken together, our results demonstrate differential propensities of CHS paralogs in terms of the accumulation of flavonoids and their relative substrate selectivities.


Asunto(s)
Variación Genética , Sintasas Poliquetidas/genética , Rheum/enzimología , Rheum/genética , Homología de Secuencia de Ácido Nucleico , Secuencia de Aminoácidos , Antraquinonas/metabolismo , Vías Biosintéticas/genética , Southern Blotting , Cromatografía Líquida de Alta Presión , Células Clonales , Simulación por Computador , ADN Complementario/genética , ADN Complementario/aislamiento & purificación , Electroforesis en Gel de Poliacrilamida , Escherichia coli/metabolismo , Flavonoides/biosíntesis , Regulación de la Expresión Génica de las Plantas , Genoma de Planta , Cinética , Metaboloma , Filogenia , Sintasas Poliquetidas/química , Regiones Promotoras Genéticas/genética , Proteómica , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas Recombinantes/metabolismo , Alineación de Secuencia , Espectrometría de Masas en Tándem
9.
Funct Integr Genomics ; 14(2): 381-99, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24522789

RESUMEN

Picrorhiza kurrooa synthesizes a large array of pharmacologically important monoterpenoid iridoid glycosides called picrosides. Although chemical profile and pharmacological activities of P. kurrooa have been extensively studied, limited attempts have been made to decipher the biosynthetic route and to identify the key regulatory genes involved in picroside biosynthesis. In the present study, NADPH-cytochrome P450 reductase, a key enzyme involved in electron transfer to cytochrome P450s was identified from P. kurrooa. The full length cDNA (2679 bp) contained an open reading frame of 2133 bp, corresponding to 710 amino acids. PkCPR was heterologously expressed in Escherichia coli and the kinetic parameters of the recombinant enzyme were determined. Specific activity, V max and K m of PkCPR were found to be 5.8 ± 0.05 µmol min(-1) mg(-1), 8.1 ± 0.12 µmol min(-1) mg(-1) and 7.8 µM, respectively. PkCPR was found to be spatially regulated at transcript level, being maximally expressed in leaf tissues. Altitude was found to have a positive effect on the picroside concentration and the picroside content positively correlated with the PkCPR transcript levels in samples collected at varied altitudes. Further, transcript profiling under methyl jasmonate, salicylic acid, 2,4-dicholorophenoxy acetic acid and UV-B elicitations displayed differential transcriptional regulation of PkCPR that fully corroborated with the identified cis-elements within the PkCPR promoter. Expression of PkCPR was inducible by UV-B and phytohormone elicitation, indicating that the PkCPR is possibly related to defence reactions, including biosynthesis of secondary metabolites. Present study is so far the only report of identification and functional characterization of CPR ortholog from P. kurrooa.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , NADPH-Ferrihemoproteína Reductasa/metabolismo , Picrorhiza/enzimología , Hojas de la Planta/enzimología , Proteínas de Plantas/metabolismo , Ácido 2,4-Diclorofenoxiacético/farmacología , Acetatos/farmacología , Altitud , Ciclopentanos/farmacología , Activación Enzimática , Escherichia coli/genética , Escherichia coli/metabolismo , Redes Reguladoras de Genes , Glucósidos Iridoides/metabolismo , Cinética , Redes y Vías Metabólicas , NADPH-Ferrihemoproteína Reductasa/genética , Oxidación-Reducción , Oxilipinas/farmacología , Picrorhiza/efectos de los fármacos , Picrorhiza/genética , Reguladores del Crecimiento de las Plantas/farmacología , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/genética , Proteínas de Plantas/genética , Regiones Promotoras Genéticas , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Ácido Salicílico/farmacología , Transcripción Genética
10.
BMC Biotechnol ; 14: 89, 2014 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-25416924

RESUMEN

BACKGROUND: Pharmacological investigations position withanolides as important bioactive molecules demanding their enhanced production. Therefore, one of the pivotal aims has been to gain knowledge about complete biosynthesis of withanolides in terms of enzymatic and regulatory genes of the pathway. However, the pathway remains elusive at the molecular level. P450s monooxygenases play a crucial role in secondary metabolism and predominantly help in functionalizing molecule core structures including withanolides. RESULTS: In an endeavor towards identification and characterization of different P450s, we here describe molecular cloning, characterization and expression analysis of two A-type P450s, WsCYP98A and WsCYP76A from Withania somnifera. Full length cDNAs of WsCYP98A and WsCYP76A have open reading frames of 1536 and 1545 bp encoding 511 (58.0 kDa) and 515 (58.7 kDa) amino acid residues, respectively. Entire coding sequences of WsCYP98A and WsCYP76A cDNAs were expressed in Escherichia coli BL21 (DE3) using pGEX4T-2 expression vector. Quantitative real-time PCR analysis indicated that both genes express widely in leaves, stalks, roots, flowers and berries with higher expression levels of WsCYP98A in stalks while WsCYP76A transcript levels were more obvious in roots. Further, transcript profiling after methyl jasmonate, salicylic acid, and gibberellic acid elicitations displayed differential transcriptional regulation of WsCYP98A and WsCYP76A. Copious transcript levels of both P450s correlated positively with the higher production of withanolides. CONCLUSIONS: Two A-types P450 WsCYP98A and WsCYP76A were isolated, sequenced and heterologously expressed in E. coli. Both P450s are spatially regulated at transcript level showing differential tissue specificity. Exogenous elicitors acted as both positive and negative regulators of mRNA transcripts. Methyl jasmonate and salicylic acid resulted in copious expression of WsCYP98A and WsCYP76A. Enhanced mRNA levels also corroborated well with the increased accumulation of withanolides in response to elicitations. The empirical findings suggest that elicitors possibly incite defence or stress responses of the plant by triggering higher accumulation of withanolides.


Asunto(s)
Sistema Enzimático del Citocromo P-450/genética , Reguladores del Crecimiento de las Plantas/farmacología , Proteínas de Plantas/genética , Withania/enzimología , Acetatos/farmacología , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Ciclopentanos/farmacología , Sistema Enzimático del Citocromo P-450/química , Sistema Enzimático del Citocromo P-450/metabolismo , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Giberelinas/farmacología , Datos de Secuencia Molecular , Oxilipinas/farmacología , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Salicilatos/farmacología , Alineación de Secuencia , Withania/clasificación , Withania/efectos de los fármacos , Withania/genética , Witanólidos/metabolismo
11.
J Phys Condens Matter ; 36(17)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38224622

RESUMEN

The atomic mobility in liquid pure gallium and a gallium-nickel alloy with 2 at% of nickel is studied experimentally by incoherent quasielastic neutron scattering. The integral diffusion coefficients for all-atom diffusion are derived from the experimental data at different temperatures. DFT-basedab-initiomolecular dynamics (MD) is used to find numerically the diffusion coefficient of liquid gallium at different temperatures, and numerical theory results well agree with the experimental findings at temperatures below 500 K. Machine learning force fields derived fromab-initiomolecular dynamics (AIMD) overestimate within a small 6% error the diffusion coefficient of pure gallium within the genuine AIMD. However, they better agree with experiment for pure gallium and enable the numerical finding of the diffusion coefficient of nickel in the considered melted alloy along with the diffusion coefficient of gallium and integral diffusion coefficient, that agrees with the corresponding experimental values within the error bars. The temperature dependence of the gallium diffusion coefficientDGa(T)follows the Arrhenius law experimentally for all studied temperatures and below 500 K also in the numerical simulations. However,DGa(T)can be well described alternatively by an Einstein-Stokes dependence with the metallic liquid viscosity following the Arrhenius law, especially for the MD simulation results at all studied temperatures. Moreover, a novel variant of the excess entropy scaling theory rationalized our findings for gallium diffusion. Obtained values of the Arrhenius activation energies are profoundly different in the competing theoretical descriptions, which is explained by different temperature-dependent prefactors in the corresponding theories. The diffusion coefficient of gallium is significantly reduced (at the same temperature) in a melted alloy with natural nickel, even at a tiny 2 at% concentration of nickel, as compared with its pure gallium value. This highly surprising behavior contradicts the existing excess entropy scaling theories and opens a venue for further research.

12.
Mol Biol Rep ; 40(12): 7007-16, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24190485

RESUMEN

Withania somnifera (L.) Dunal synthesizes large array of pharmacologically active secondary metabolites known as withanolides. It has been extensively investigated in terms of chemistry and bioactivity profiling. However, there exists fragmentary information about the dynamics of withanolide biosynthesis at different phenophases in concert with the expression analysis of key pathway genes. In the present study, two morpho-chemovariants of W. somnifera were harvested at five developmental stages, dissected into leaf and root tissues and assayed for three major withanolides viz. withanolide-A (WS-1), withanone (WS-2) and withaferin A (WS-3) content using high performance liquid chromatography. The present investigation also analyzed the expression pattern of five withanolide biosynthetic pathway genes namely squalene synthase, squalene epoxidase, cycloartenol synthase, cytochrome P450 reductase 1, cytochrome P450 reductase 2 to corroborate with the metabolite flux at different developmental stages. The relative transcript profiles of identified genes at various ontogenetic stages illustrated significant variation in leaf and root tissues and were largely concurrent with the alteration in withanolide pool. Comparatively, the concentrations of withanolide A, withanone and withaferin A along with expression levels of all the five genes were appreciably higher in the leaves than in roots. Relative dynamics in terms of quantitative and qualitative profiles of withanolides in leaf and root tissues revealed least correspondence between the pattern of accumulation, possibly indicting towards de novo tissue-specific biosynthesis.


Asunto(s)
Regulación de la Expresión Génica de las Plantas , Genes de Plantas , Withania/genética , Withania/metabolismo , Witanólidos/metabolismo , Vías Biosintéticas/genética , Regulación del Desarrollo de la Expresión Génica , Fenotipo , Hojas de la Planta/metabolismo , Raíces de Plantas/metabolismo , Factores de Tiempo , Withania/crecimiento & desarrollo , Witanólidos/química
13.
Ann Med Surg (Lond) ; 85(5): 1468-1474, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37229096

RESUMEN

COVID-19 infection is associated with high mortality, and despite extensive studying the scientific society is still working to find a definitive treatment. Some experts postulated a beneficial role of Deferoxamine. Aim: The aim of this study was to compare the outcomes of COVID-19 adult patients admitted to the ICU who received deferoxamine to those who received standard of care. Methods: Prospective observational cohort study, in the ICU of a tertiary referral hospital in Saudi Arabia to compare all-cause hospital mortality between COVID-19 patients who received deferoxamine and standard of care. Results: A total of 205 patients were enrolled, with an average age of 50.1±14.3, 150 patients received standard of care only, and 55 patients received deferoxamine additionally. Hospital mortality was lower in deferoxamine group (25.5 vs. 40.7%, 95% CI=1.3-29.2%; P=0.045). Clinical status score upon discharge was lower in deferoxamine group (3.6±4.3 vs. 6.2±4, 95% CI: 1.4-3.9; P<0.001), as was the difference between discharge score and admission score (indicating clinical improvement). More patients admitted with mechanical ventilation were successfully extubated in the deferoxamine group (61.5 vs. 14.3%, 95% CI: 15-73%; P=0.001), with a higher median ventilator-free days. There were no differences between groups in adverse events. Deferoxamine group was associated with hospital mortality [odds ratio=0.46 (95% CI: 0.22-0.95); P=0.04]. Conclusions: Deferoxamine may have mortality and clinical improvement benefits in COVID-19 adults admitted to ICU. Further powered and controlled studies are required.

14.
Genet Mol Res ; 11(1): 679-92, 2012 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-22535404

RESUMEN

Identification of new sources of salt tolerance is particularly important to develop crop varieties suitable for saline soils. We evaluated 129 Pakistani and 58 exotic wheat landraces/cultivars grown in Hoagland's hydroponic nutrient solution, under control (tap water equivalent to 10 mM salt) and salt stress (200 mM NaCl) conditions. Forty-four genotypes were also tested under 250 mM NaCl stress. High heritability and positive correlations suggested that number of tillers per plant, root length, root fresh and dry weights, and shoot fresh and dry weights are associated with salt tolerance and could be used as selection criteria. SSR markers revealed high genetic variation in the wheat genotypes. Twelve SSR markers (cfd 1, cfd 9, cfd 18, cfd 46, cfd 49, cfd 183, wmc 11, wmc 17, wmc 18, wmc 154, wmc 432, and wmc 503) were found to be associated with salt tolerance because they were amplified in tolerant genotypes only. Five markers, cfd 9, cfd 18, cfd 183, wmc 96, and wmc 405, were identified as most suitable to evaluate salt tolerance because they were associated with four or more salt tolerance traits studied. Cultivars Pasban 90, accessions 10790, 10828, 10823, and 4098805 from Pakistan and Sakha-92 from Egypt performed best at both stress levels.


Asunto(s)
Tolerancia a la Sal/genética , Triticum/genética , Alelos , Estudios de Asociación Genética , Genotipo , Repeticiones de Microsatélite , Fenotipo , Filogenia , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/genética , Raíces de Plantas/crecimiento & desarrollo , Brotes de la Planta/efectos de los fármacos , Brotes de la Planta/genética , Brotes de la Planta/crecimiento & desarrollo , Cloruro de Sodio/farmacología , Triticum/clasificación , Triticum/efectos de los fármacos
15.
Braz J Biol ; 84: e254816, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35019106

RESUMEN

Pakistan is an agricultural country and fisheries play a very important role in the economic development of the country. Different diseases are prevalent in Pakistani fish but information related to the causative agents is not well-known. Keeping in view the significance of bacterial pathogens as the causative agents of multiple fish diseases, the present study was conducted for identification, characterization and analysis of virulence genes of Aeromonas spp. isolated from diseased fishes. A total of fifty fish samples having multiple clinical indications were collected from different fish farms of district Kasur, Punjab Pakistan. For isolation of Aeromonas spp. samples were enriched and inoculated on Aeromonas isolation medium. Isolates were identified and characterized by different biochemical tests, Analytical Profile Index (API) 20E kit and Polymerase Chain Reaction (PCR) assays. All isolates were screened for three putative virulence genes including aerolysin (aer), haemolysin (hyl) and heat labile cytotonic enterotoxin (alt). Seven isolates of Aeromonas (A.) hydrophila were retrieved and identified based on API 20E. These isolates were further confirmed as A. hydrophila on the basis of PCR assays. Three isolates were detected positive for the presence of virulence genes (alt and hyl). Whereas aerolysin (aer) gene was not present in any of A. hydrophila isolates. The present study confirmed A. hydrophila as the causative agent of epizootic ulcerative syndrome and motile Aeromonas septicemia in fish farms of district Kasur, Punjab Pakistan. Moreover, detection of two virulence genes (alt and hyl) in A. hydrophila isolates is a threat for fish consumers of study area.


Asunto(s)
Aeromonas , Infecciones por Bacterias Gramnegativas , Aeromonas/genética , Aeromonas hydrophila/genética , Animales , Enterotoxinas/genética , Peces , Infecciones por Bacterias Gramnegativas/epidemiología , Infecciones por Bacterias Gramnegativas/veterinaria , Pakistán
16.
J Healthc Eng ; 2022: 7745132, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36397885

RESUMEN

With the advancement of camera and wireless technologies, surveillance camera-based occupancy has received ample attention from the research community. However, camera-based occupancy monitoring and wireless channels, especially Wi-Fi hotspot, pose serious privacy concerns and cybersecurity threats. Eavesdroppers can easily access confidential multimedia information and the privacy of individuals can be compromised. As a solution, novel encryption techniques for the multimedia data concealing have been proposed by the cryptographers. Due to the bandwidth limitations and computational complexity, traditional encryption methods are not applicable to multimedia data. In traditional encryption methods such as Advanced Encryption Standard (AES) and Data Encryption Standard (DES), once multimedia data are compressed during encryption, correct decryption is a challenging task. In order to utilize the available bandwidth in an efficient way, a novel secure video occupancy monitoring method in conjunction with encryption-compression has been developed and reported in this paper. The interesting properties of Chebyshev map, intertwining map, logistic map, and orthogonal matrix are exploited during block permutation, substitution, and diffusion processes, respectively. Real-time simulation and performance results of the proposed system show that the proposed scheme is highly sensitive to the initial seed parameters. In comparison to other traditional schemes, the proposed encryption system is secure, efficient, and robust for data encryption. Security parameters such as correlation coefficient, entropy, contrast, energy, and higher key space prove the robustness and efficiency of the proposed solution.


Asunto(s)
Algoritmos , Compresión de Datos , Humanos , Compresión de Datos/métodos , Seguridad Computacional , Confidencialidad , Tecnología Inalámbrica
17.
Rom J Anaesth Intensive Care ; 29(1): 1-7, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36844963

RESUMEN

Background: SARS-CoV-2 infection demonstrates a wide range of severity. More severe cases demonstrate a cytokine storm with elevated serum interleukin-6, hence IL-6 receptor antibody tocilizumab was tried for the management of severe cases. Aims: Effect of tocilizumab on ventilator-free days among critically ill SARS-CoV-2 patients. Method: Retrospective propensity score matching study, comparing mechanically ventilated patients who received tocilizumab to a control group. Results: 29 patients in the intervention group were compared to 29 controls. Matched groups were similar. Ventilator-free days were more numerous in the intervention group (SHR 2.7, 95% CI: 1.2 - 6.3; p = 0.02), ICU mortality rate was not different (37.9% versus 62%, p = 0.1), actual ventilator-free periods were significantly longer in tocilizumab group (mean difference 4.7 days; p = 0.02). Sensitivity analysis showed a significantly lower hazard ratio of death in tocilizumab group (HR 0.49, 95% CI: 0.25 - 0.97; p = 0.04). There was no difference in positive cultures among groups (55.2% in tocilizumab group versus 34.5% in the control; p = 0.1). Conclusion: Tocilizumab may improve the composite outcome of ventilator-free days at day 28 among mechanically ventilated SARS-CoV-2 patients; it is associated with significantly longer actual ventilator-free periods, and insignificantly lower mortality and higher superinfection.

18.
Heart Lung ; 56: 118-124, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35839546

RESUMEN

BACKGROUND: SARS-CoV-2 infection demonstrates a wide range of severity, with more severe cases presenting with a cytokine storm with elevated serum interleukin-6; hence, the interleukin-6 receptor antibody tocilizumab was used for the management of severe cases. OBJECTIVE: To explore the effect of tocilizumab on ventilator-free day composite outcomes among critically ill patients with SARS-CoV-2 infection. METHODS: This retrospective propensity score-matching study compared mechanically ventilated patients who received tocilizumab to a control group. RESULTS: Twenty-nine patients in the intervention group were compared to 29 controls. The matched groups were similar. The ventilator-free days composite outcome was higher in the intervention group (sub-distribution hazard ratio 2.7, 95% confidence interval [CI]: 1.2-6.3; p = 0.02), the mortality rate in the intensive care unit was not different (37.9% vs 62%, p = 0.1), and actual ventilator-free days were significantly longer in the tocilizumab group (mean difference 4.7 days; p = 0.02). Sensitivity analysis showed a significantly lower hazard ratio for death in the tocilizumab group (HR 0.49, 95% CI: 0.25-0.97; p = 0.04). Positive cultures were not significantly different among the groups (55.2% vs 34.5% in the tocilizumab and control groups, respectively; p = 0.1). CONCLUSIONS: Tocilizumab may improve the composite outcome of ventilator-free days at day 28 among mechanically ventilated patients with SARS-CoV-2 infection. It is associated with significantly longer actual ventilator-free days, insignificantly lower mortality, and higher superinfection.


Asunto(s)
COVID-19 , Humanos , SARS-CoV-2 , Estudios Retrospectivos , Interleucina-6 , Receptores de Interleucina-6 , Medición de Riesgo , Resultado del Tratamiento , Respiración Artificial , Tratamiento Farmacológico de COVID-19
19.
J Healthc Qual Res ; 36(3): 150-155, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33640310

RESUMEN

INTRODUCTION: Like many other countries, Pakistan's healthcare system is divided into the public and the private sector. According to some studies and the mindset of many Pakistani people, private hospitals provide better services than government hospitals. PURPOSE: The paucity of research studies compelled us to compare the understanding of prescription among outpatients of the government and private hospitals since the understanding of prescription by the patient is an important patient care indicator according to WHO. METHOD: A cross sectional study was conducted by virtue of convenience sampling. The study included 365 patients; 182 from the government sector and 183 from the private sector. The study was conducted over a period of 3 months. A structured questionnaire was prepared to gather data that was analyzed using SPSS Version 22.0. RESULTS: Patients from both government and private hospitals got no counseling while only 45.9% of the government hospital patients and 65.9% of private hospital patients were satisfied with the counseling they received. Our study concluded that the role of a pharmacist must be extended besides dispensing only, in counseling and educating patients to reduce the burden on the physicians and hospitals as well. CONCLUSION: It was concluded that although the patients of private hospitals scored somewhat better at answering the questions than the government hospital patients but they failed to hit the benchmark. Their slightly better results were attributed to higher education levels and better socioeconomic status rather than better services of the hospital.


Asunto(s)
Hospitales Privados , Pacientes Ambulatorios , Estudios Transversales , Gobierno , Humanos , Pakistán , Prescripciones
20.
Braz J Biol ; 83: e246440, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34550282

RESUMEN

Utilization of modern breeding techniques for developing high yielding and uniform plant types ultimately narrowing the genetic makeup of most crops. Narrowed genetic makeup of these crops has made them vulnerable towards disease and insect epidemics. For sustainable crop production, genetic variability of these crops must be broadened against various biotic and abiotic stresses. One of the ways to widen genetic configuration of these crops is to identify novel additional sources of durable resistance. In this regard crops wild relatives are providing valuable sources of allelic diversity towards various biotic, abiotic stress tolerance and quality components. For incorporating novel variability from wild relative's wide hybridization technique has become a promising breeding method. For this purpose, wheat-Th. bessarabicum amphiploid, addition and translocation lines have been screened in field and screen house conditions to get novel sources of yellow rust and Karnal bunt resistant. Stripe rust screening under field conditions has revealed addition lines 4JJ and 6JJ as resistant to moderately resistant while addition lines 3JJ, 5JJ, 7JJ and translocation lines Tr-3, Tr-6 as moderately resistant wheat-Thinopyrum-bessarabicum genetic stock. Karnal bunt screening depicted addition lines 5JJ and 4JJ as highly resistant genetic stock. These genetic stocks may be used to introgression novel stripe rust and Karnal bunt resistance from the tertiary gene pool into susceptible wheat backgrounds.


Asunto(s)
Basidiomycota , Triticum , Basidiomycota/genética , Cromosomas de las Plantas , Resistencia a la Enfermedad/genética , Fitomejoramiento , Enfermedades de las Plantas/genética , Triticum/genética
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