Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
1.
Braz. j. biol ; 83: e246436, 2023. tab, graf
Artigo em Inglês | LILACS-Express | MEDLINE, LILACSEXPRESS | ID: biblio-1339391

RESUMO

Abstract Application of different fertilizers to check the efficiency of expression of Bt (Bacillus thuringiensis) gene in one of the leading commercialized crops (cotton) against Lepidopteran species is of great concern. The expression of Cry protein level can be controlled by the improvement of nutrients levels. Therefore, the myth of response of Cry toxin to different combinations of NP fertilizers was explored in three Bt cotton cultivars. Combinations include three levels of nitrogen and three levels of phosphorus fertilizers. Immunostrips and Cry gene(s) specific primer based PCR (Polymerase Chain Reaction) analysis were used for the presence of Bt gene that unveiled the presence of Cry1Ac gene only. Further, the ELISA (enzyme-linked immunosorbent assay) kit was used to quantify the expression of Cry1Ac protein. Under various NP fertilizers rates, the level of toxin protein exhibited highly significant differences. The highest toxin level mean was found to be 2.3740 and 2.1732 µg/g under the treatment of N150P75 kg ha-1 combination while the lowest toxin level mean was found to be 0.9158 and 0.7641 µg/g at the N50P25 kg ha-1 level at 80 and 120 DAS (Days After Sowing), respectively. It was concluded from the research that the usage of NP fertilizers has a positive relation with the expression of Cry1Ac toxin in Bt cotton. We recommend using the N150P50 kg ha-1 level as the most economical and practicable fertilizer instead of the standard dose N100P50 kg ha-1 to get the desired level of Cry1Ac level for long lasting plant resistance (<1.5). The revised dose of fertilizer may help farmers to avoid the cross-resistance development in contradiction of insect pests.


Resumo A aplicação de diferentes fertilizantes para verificar a eficiência da expressão do gene Bt (Bacillus thuringiensis) em uma das principais culturas comercializadas (algodão) contra espécies de lepidópteros é uma grande preocupação. A expressão do nível de proteína Cry pode ser controlada pela melhoria dos níveis de nutrientes. Portanto, o mito da resposta da toxina Cry a diferentes combinações de fertilizantes NP foi explorado em três cultivares de algodão Bt. As combinações incluem três níveis de nitrogênio e três níveis de fertilizantes de fósforo. A análise de PCR (reação em cadeia da polimerase) específica para o gene (s) Immunostrips e Cry (s) foi usada para a presença do gene Bt que revelou a presença do gene Cry1Ac apenas. Além disso, o kit ELISA (ensaio de imunoabsorção enzimática) foi usado para quantificar a expressão da proteína Cry1Ac. Sob várias taxas de fertilizantes NP, o nível de proteína de toxina exibiu diferenças altamente significativas. A média do nível mais alto de toxina foi de 2,3740 e 2,1732 µg / g sob o tratamento da combinação N150P75 kg ha-1, enquanto a média do nível mais baixo de toxina foi de 0,9158 e 0,7641 µg / g no nível de N50P25 kg ha-1 em 80 e 120 DAS (dias após a semeadura), respectivamente. Concluiu-se com a pesquisa que o uso de fertilizantes NP tem relação positiva com a expressão da toxina Cry1Ac no algodão Bt. Recomendamos o uso do nível de N150P50 kg ha-1 como o fertilizante mais econômico e praticável em vez da dose padrão N100P50 kg ha-1 para obter o nível desejado de nível de Cry1Ac para resistência de planta de longa duração (<1,5). A dose revisada de fertilizante pode ajudar os agricultores a evitar o desenvolvimento de resistência cruzada em contradição com as pragas de insetos.

2.
Braz. j. biol ; 83: e246440, 2023. tab
Artigo em Inglês | LILACS-Express | MEDLINE, LILACSEXPRESS | ID: biblio-1339395

RESUMO

Abstract 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.


Resumo A utilização de técnicas modernas de melhoramento para o desenvolvimento de tipos de plantas uniformes e de alto rendimento, em última análise, estreitando a composição genética da maioria das culturas. A composição genética restrita dessas plantações tornou-as vulneráveis a doenças e epidemias de insetos. Para uma produção agrícola sustentável, a variabilidade genética dessas culturas deve ser ampliada contra vários estresses bióticos e abióticos. Uma das maneiras de ampliar a configuração genética dessas culturas é identificar novas fontes adicionais de resistência durável. A esse respeito, os parentes selvagens das culturas estão fornecendo fontes valiosas de diversidade alélica para vários componentes de qualidade e tolerância ao estresse abiótico e biótico. Para incorporar a nova variabilidade da ampla técnica de hibridização de parente selvagem tornou-se um método de reprodução promissor. Para esse efeito, trigo-Th. As linhas anfiploides, de adição e translocação de bessarabicum foram selecionadas em condições de campo e de casa de tela para obter novas fontes de ferrugem amarela e resistência ao bunt de Karnal. A triagem de ferrugem em faixas em condições de campo revelou as linhas de adição 4JJ e 6JJ como resistentes a moderadamente resistentes, enquanto as linhas de adição 3JJ, 5JJ, 7JJ e as linhas de translocação Tr-3, Tr-6 como estoque genético de trigo-Thinopyrum bessarabicum moderadamente resistente. A triagem Karnal bunt descreveu as linhas de adição 5JJ e 4JJ como estoque genético altamente resistente. Esses estoques genéticos podem ser usados para introgressão da nova ferrugem e resistência ao bunt de Karnal do pool genético terciário em origens de trigo suscetíveis.

3.
Braz J Biol ; 83: e246440, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34550282

RESUMO

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.


Assuntos
Basidiomycota , Triticum , Basidiomycota/genética , Cromossomos de Plantas , Resistência à Doença/genética , Melhoramento Vegetal , Doenças das Plantas/genética , Triticum/genética
4.
Braz J Biol ; 83: e246436, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495159

RESUMO

Application of different fertilizers to check the efficiency of expression of Bt (Bacillus thuringiensis) gene in one of the leading commercialized crops (cotton) against Lepidopteran species is of great concern. The expression of Cry protein level can be controlled by the improvement of nutrients levels. Therefore, the myth of response of Cry toxin to different combinations of NP fertilizers was explored in three Bt cotton cultivars. Combinations include three levels of nitrogen and three levels of phosphorus fertilizers. Immunostrips and Cry gene(s) specific primer based PCR (Polymerase Chain Reaction) analysis were used for the presence of Bt gene that unveiled the presence of Cry1Ac gene only. Further, the ELISA (enzyme-linked immunosorbent assay) kit was used to quantify the expression of Cry1Ac protein. Under various NP fertilizers rates, the level of toxin protein exhibited highly significant differences. The highest toxin level mean was found to be 2.3740 and 2.1732 µg/g under the treatment of N150P75 kg ha-1 combination while the lowest toxin level mean was found to be 0.9158 and 0.7641 µg/g at the N50P25 kg ha-1 level at 80 and 120 DAS (Days After Sowing), respectively. It was concluded from the research that the usage of NP fertilizers has a positive relation with the expression of Cry1Ac toxin in Bt cotton. We recommend using the N150P50 kg ha-1 level as the most economical and practicable fertilizer instead of the standard dose N100P50 kg ha-1 to get the desired level of Cry1Ac level for long lasting plant resistance (<1.5). The revised dose of fertilizer may help farmers to avoid the cross-resistance development in contradiction of insect pests.


Assuntos
Proteínas Hemolisinas , Mariposas , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/genética , Endotoxinas/genética , Fertilizantes , Proteínas Hemolisinas/genética , Resistência a Inseticidas , Larva , Nitrogênio , Fósforo , Plantas Geneticamente Modificadas/genética
5.
Anim Nutr ; 7(1): 1-10, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33997325

RESUMO

It has been well recognized that interactions between the gut microbiota and host-metabolism have a proven effect on health. The gut lumen is known for harboring different bacterial communities. Microbial by-products and structural components, which are derived through the gut microbiota, generate a signaling response to maintain homeostasis. Gut microbiota is not only involved in metabolic disorders, but also participates in the regulation of reproductive hormonal function. Bacterial phyla, which are localized in the gut, allow for the metabolization of steroid hormones through the stimulation of different enzymes. Reproductive hormones such as progesterone, estrogen and testosterone play a pivotal role in the successful completion of reproductive events. Disruption in this mechanism may lead to reproductive disorders. Environmental bacteria can affect the metabolism, and degrade steroid hormones and their relevant compounds. This behavior of the bacteria can safely be implemented to eliminate steroidal compounds from a polluted environment. In this review, we summarize the metabolism of steroid hormones on the regulation of gut microbiota and vice-versa, and also examined the significant influence this process has on various events of reproductive function. Altogether, the evidence suggests that steroid hormones and gut microbiota exert a central role in the modification of host bacterial action and impact the reproductive efficiency of animals and humans.

6.
Preprint em Inglês | medRxiv | ID: ppmedrxiv-21254794

RESUMO

BackgroundSARS-CoV-2 infection demonstrates a wide range of severity, the 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. ObjectivesThe effect of Tocilizumab treatment on the composite outcome of ventilator free days, among critically ill SARS-CoV-2 patients. MethodRetrospective observational propensity score matching study, comparing mechanically ventilated patients upon ICU admission who received Tocilizumab to a control group. Utilizing competing risk analysis method, and reporting sub-distributional hazard ratio of a composite outcome of ventilator free days at day 28. Results29 patients in the intervention group were compared to 29 patients in the control group. Matched groups were similar at base line. The primary outcome of ventilator free days was higher in the intervention group (SHR 2.7, 95% CI: 1.2 - 6.3; p = 0.02), crude ICU mortality rate was not different between Tocilizumab and control groups (37.9% versus 62% respectively, p = 0.1), actual ventilator free days were significantly longer in Tocilizumab group (mean difference 4.7 days, 95% CI 1.1 - 8.3; p = 0.02). Sensitivity analysis by Cox regression showed a significantly lower hazard ratio of death in Tocilizumab group (HR 0.49, 95% CI: 0.25 - 0.97; p = 0.04). While there was no difference in grown positive cultures among groups (55.2% in Tocilizumab group versus 34.5% in the control, 95% CI of difference: -7.11% to 54.4%; p = 0.1). ConclusionTocilizumab 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 days, and insignificantly lower mortality and superinfection.

7.
J Healthc Qual Res ; 36(3): 150-155, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33640310

RESUMO

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.

8.
Sensors (Basel) ; 20(7)2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32230988

RESUMO

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.

9.
Planta ; 251(1): 15, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31776718

RESUMO

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.


Assuntos
Policetídeo Sintases/genética , Aciltransferases/genética , Aciltransferases/metabolismo , Policetídeo Sintases/metabolismo , Regiões Promotoras Genéticas/genética
10.
Cureus ; 11(5): e4774, 2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31367493

RESUMO

INTRODUCTION: Stroke is a major cause of death with hypertension being identified as an important modifiable risk factor. Prompt identification of stroke symptoms and timely management is noted to be significant in lowering both morbidity and mortality. Baseline stroke knowledge in hypertensive patients is crucial to develop effectively targeted, and appropriate health promotion campaigns; thus, the main objectives of this study are to assess the awareness of stroke and to determine health-seeking practices among hypertensive patients. MATERIALS AND METHODS: A standardized questionnaire survey regarding awareness and practices about stroke among hypertensive patients was conducted in a tertiary care hospital of Islamabad. The sample size was calculated as 384. RESULTS: Out of 384 patients evaluated, 80.5% had heard about stroke, 71.6% knew someone with stroke, and 76% identified the brain as the organ affected. Sudden onset numbness of limb (66.9%) and hypertension (93.5%) were common warning symptom and risk factor identified. 87.5% would take stroke patients to a hospital. Only 45.1% of the patients took their medications regularly, and 38% checked their blood pressure. CONCLUSION: Majority of hypertensive patients were aware of stroke but the awareness of risk factors and warning signs was poor. Stroke prevention practices were also sub-optimal. There is a need to increase knowledge regarding risk factors, which will benefit the community at large.

11.
Toxins (Basel) ; 10(8)2018 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-30082604

RESUMO

The mycotoxin, ochratoxin-A (OTA), produced by some fungi, and is a natural contaminant of many foods and animal feeds worldwide. Due to its toxic effects, the recommended maximum daily intake of OTA for poultry feeds is 0.1 mg OTA/kg (ECR2006/575/EC); this dose does not induce changes in hepatic/renal parameters, but decreases thymus size and serum globulin concentrations. Accordingly, in this study, we assessed quantitatively the total circulating IgY and IgA serum levels, in chicks consuming a 0.1 mg OTA/kg diet (limit) and higher doses (0.3⁻1.1 mg OTA/kg diet) for 14 or 21 days. We also evaluated other immunological parameters (thymus, bursa of Fabricius, and spleen weights and leukocyte profiles) at day 21. Decreased IgY serum levels were observed in all OTA-treated groups (p < 0.05). In the low-dose group, IgA levels were decreased on day 21, but not on day 14. The size of the thymus and the bursa of Fabricius was decreased in all OTA-treated groups (p < 0.05), whereas reduced spleen size and altered leukocyte profiles were detected only in the high-dose group (p < 0.05). We concluded that chronic exposure to OTA, even at the recommended highest dose, affected IgY and IgA production in chicks.


Assuntos
Imunoglobulina A/sangue , Imunoglobulinas/sangue , Ocratoxinas/toxicidade , Animais , Bolsa de Fabricius/efeitos dos fármacos , Bolsa de Fabricius/patologia , Galinhas , Contagem de Leucócitos , Tamanho do Órgão/efeitos dos fármacos , Baço/efeitos dos fármacos , Baço/patologia , Timo/efeitos dos fármacos , Timo/patologia
12.
East Mediterr Health J ; 24(1): 33-41, 2018 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-29658619

RESUMO

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.


Assuntos
Doenças não Transmissíveis/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Dieta/estatística & dados numéricos , Exercício Físico , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Pessoa de Meia-Idade , Sobrepeso/epidemiologia , Paquistão/epidemiologia , Prevalência , Características de Residência , Fatores de Risco , Fatores Sexuais , Fumar/epidemiologia , Fatores Socioeconômicos , Adulto Jovem
13.
Plant Mol Biol ; 96(1-2): 197-215, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29270891

RESUMO

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.


Assuntos
Camptotecina/metabolismo , Magnoliopsida/metabolismo , Transcriptoma/genética , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Perfilação da Expressão Gênica , Magnoliopsida/genética , MicroRNAs/genética
14.
Phytochem Rev ; 17(3): 573-609, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-32214920

RESUMO

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.

15.
Biomed Res Int ; 2017: 3872783, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29119106

RESUMO

GRAPPA (Generalized Autocalibrating Partially Parallel Acquisition) is a widely used parallel MRI reconstruction technique. The processing of data from multichannel receiver coils may increase the storage and computational requirements of GRAPPA reconstruction. Random projection on GRAPPA (RP-GRAPPA) uses random projection (RP) method to overcome the computational overheads of solving large linear equations in the calibration phase of GRAPPA, saving reconstruction time. However, RP-GRAPPA compromises the reconstruction accuracy in case of large reductions in the dimensions of calibration equations. In this paper, we present the implementation of GRAPPA reconstruction method using potential iterative solvers to estimate the reconstruction coefficients from the randomly projected calibration equations. Experimental results show that the proposed methods withstand the reconstruction accuracy (visually and quantitatively) against large reductions in the dimension of linear equations, when compared with RP-GRAPPA reconstruction. Particularly, the proposed method using conjugate gradient for least squares (CGLS) demonstrates more savings in the computational time of GRAPPA, without significant loss in the reconstruction accuracy, when compared with RP-GRAPPA. It is also demonstrated that the proposed method using CGLS complements the channel compression method for reducing the computational complexities associated with higher channel count, thereby resulting in additional memory savings and speedup.


Assuntos
Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/normas , Modelos Teóricos , Calibragem
16.
PLoS One ; 12(6): e0179155, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28662128

RESUMO

Chalcone synthase constitutes a functionally diverse gene family producing wide range of flavonoids by catalyzing the initial step of the phenylpropanoid pathway. There is a pivotal role of flavonoids in pollen function as they are imperative for pollen maturation and pollen tube growth during sexual reproduction in flowering plants. Here we focused on medicinally important fruit-bearing shrub Grewia asiatica. It is a rich repository of flavonoids. The fruits are highly acclaimed for various putative health benefits. Despite its importance, full commercial exploitation is hampered due to two drawbacks which include short shelf life of its fruits and larger seed volume. To circumvent these constraints, seed abortion is one of the viable options. Molecular interventions tested in a number of economic crops have been to impair male reproductive function by disrupting the chalcone synthase (CHS) gene activity. Against this backdrop the aim of the present study included cloning and characterization of two full-length cDNA clones of GaCHS isoforms from the CHS multigene family. These included GaCHS1 (NCBI acc. KX129910) and GaCHS2 (NCBI acc. KX129911) with an ORF of 1176 and 1170 bp, respectively. GaCHSs were heterologously expressed and purified in E. coli to validate their functionality. Functionality of CHS isoforms was also characterized via enzyme kinetic studies using five different substrates. We observed differential substrate specificities in terms of their Km and Vmax values. Accumulation of flavonoid constituents naringenin and quercetin were also quantified and their relative concentrations corroborated well with the expression levels of GaCHSs. Further, our results demonstrate that GaCHS isoforms show differential expression patterns at different reproductive phenological stages. Transcript levels of GaCHS2 were more than its isoform GaCHS1 at the anthesis stage of flower development pointing towards its probable role in male reproductive maturity.


Assuntos
Aciltransferases/metabolismo , Flavonoides/metabolismo , Regulação Enzimológica da Expressão Gênica , Grewia/metabolismo , Isoenzimas/metabolismo , Aciltransferases/química , Sequência de Aminoácidos , Cromatografia Líquida de Alta Pressão , Grewia/classificação , Isoenzimas/química , Cinética , Filogenia , Homologia de Sequência de Aminoácidos , Espectrometria de Massas por Ionização por Electrospray
17.
J Healthc Eng ; 2017: 3153252, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29312654

RESUMO

Goal: The aim of this paper is to conduct a comprehensive comparative analysis between five different controllers for a drug infusion system in total intravenous anesthesia (TIVA) administration. Methods: The proposed method models a dilution chamber with first order exponential decay characteristics to represent the pharmacokinetic decay of a drug. The dilution chamber is integrated with five different control techniques with a simulation-based comparative analysis performed between them. The design process is conducted using MATLAB SISOTOOL. Results: The findings show that each controller has its own merits and demerits. The results generated using MATLAB signify and confirm the effectiveness of PI and cascaded lead controllers, with cascaded lead controller as the best control technique to automate and control the propofol delivery. Conclusion: In this paper, different control techniques for measurement-based feedback-controlled propofol delivery is confirmed with promising results. Significance: The comparative analysis showed that this drug infusion platform, merged with the proper control technique, will perform eminently in the field of total intravenous anesthesia.


Assuntos
Anestesia Intravenosa/métodos , Anestésicos Intravenosos/administração & dosagem , Bombas de Infusão/estatística & dados numéricos , Propofol/administração & dosagem , Anestésicos Intravenosos/farmacocinética , Retroalimentação , Humanos , Modelos Teóricos , Propofol/farmacocinética
18.
Case Rep Crit Care ; 2016: 5643470, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27429809

RESUMO

Retroperitoneal haemorrhage (or retroperitoneal haematoma) refers to an accumulation of blood found in the retroperitoneal space. It is a rare clinical entity with variable aetiology including anticoagulation, ruptured aortic aneurysm, acute pancreatitis, malignancy, and bleeding from renal aneurysm. Diagnosis of retroperitoneal bleed is sometimes missed or delayed as presentation is often nonspecific. Multislice CT and arteriography are important for diagnosis. There is no consensus about the best management plan for patients with retroperitoneal haematoma. Stable patients can be managed with fluid resuscitation, correction of coagulopathy if any, and blood transfusion. Endovascular options involving selective intra-arterial embolisation or stent-grafts are clearly getting more and more popularity. Open repair is usually reserved for cases when there is failure of conservative or endovascular measures to control the bleeding or expertise is unavailable and in cases where the patient is unstable. Mortality of patients with retroperitoneal haematoma remains high if appropriate and timely measures are not taken. Haemorrhage from a benign renal tumour is a rarer entity which is described in this case report which emphasizes that physicians should have a wide index of suspicion when dealing with patients presenting with significant groin, flank, abdominal, or back pain, or haemodynamic instability of unclear cause. Our patient presented with features of acute abdomen and, being pregnant, was thought of having a ruptured ectopic pregnancy.

19.
Plant Physiol ; 171(4): 2599-619, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27268960

RESUMO

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.


Assuntos
Variação Genética , Policetídeo Sintases/genética , Rheum/enzimologia , Rheum/genética , Homologia de Sequência do Ácido Nucleico , Sequência de Aminoácidos , Antraquinonas/metabolismo , Vias Biossintéticas/genética , Southern Blotting , Cromatografia Líquida de Alta Pressão , Células Clonais , Simulação por Computador , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Eletroforese em Gel de Poliacrilamida , Escherichia coli/metabolismo , Flavonoides/biossíntese , Regulação da Expressão Gênica de Plantas , Genoma de Planta , Cinética , Metaboloma , Filogenia , Policetídeo Sintases/química , Regiões Promotoras Genéticas/genética , Proteômica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes/metabolismo , Alinhamento de Sequência , Espectrometria de Massas em Tandem
20.
Saudi J Biol Sci ; 23(3): 389-96, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27081365

RESUMO

In the present work, the response surface methodology (RSM) based on a central composite rotatable design (CCRD), was used to determine optimum conditions for the extraction of antioxidant compounds from Origanum vulgare leaves. Four process variables were evaluated at three levels (31 experimental designs): methanol (70%, 80%, and 90%), the solute:solvent ratio (1:5, 1:12.5, 1:20), the extraction time (4, 10, 16 h), and the solute particle size (20, 65, 110 micron). Using RSM, a quadratic polynomial equation was obtained by multiple regression analysis for predicting optimization of the extraction protocol. Analysis of variance (ANOVA) was applied and the significant effect of the factors and their interactions were tested at 95% confidence interval. The antioxidant extract (AE) yield was significantly influenced by solvent composition, solute to solvent ratio, and time. The maximum AE was obtained at methanol (70%), liquid solid ratio (20), time (16 h), and particle size (20 micron). Predicted values thus obtained were closer to the experimental value indicating suitability of the model. Run 25 (methanol:water 70:30; solute:solvent 1:20; extraction time 16 h and solute particle size 20) showed highest TP contents (18.75 mg/g of dry material, measured as gallic acid equivalents) and DPPH radical scavenging activity (IC50 5.04 µg/mL). Results of the present study indicated good correlation between TP contents and DPPH radical scavenging activity. Results of the study indicated that phenolic compounds are powerful scavengers of free radical as demonstrated by a good correlation between TP contents and DPPH radical scavenging activity.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...