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1.
Physiol Plant ; 156(3): 278-93, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26260637

RESUMO

To understand the spread of native populations of Lepidium latifolium growing in different altitudes in Ladakh region of Western Himalayas, photosynthetic and fluorescence characteristics were evaluated in relation to their micro-environment. Three sites representing sparsely populated (SPS), moderately populated (MPS) and densely populated site (DPS) were selected. Results showed that the DPS had higher photosynthetic accumulation than MPS and SPS. The higher transpiration rate at DPS despite lower vapor pressure deficit and higher relative humidity suggest the regulation of its leaf temperature by evaporative cooling. Intrinsic soil parameters such as water holding capacity and nutrient availability also play crucial role in higher biomass here. The quantum efficiency of PSII photochemistry (Fv/Fm, non-photochemical quenching (NPQ), ΦPSII) and light curve at various PPFDs suggests better light harvesting potential and light compensation point at DPS than the other two sites. Concomitantly, plants at SPS had significantly higher lipid peroxidation, suggesting a stressful environment, and higher induction of antioxidative enzymes. Metabolic content of reduced glutathione also suggests an efficient mechanism in DPS and MPS than SPS. High light intensities at MPS are managed by specialized contrive of carotenoid pigments and PsbS gene product. Large pool of violaxanthin and lutein plays an important role in this response. It is suggested that L. latifolium is present as 'sleeper weed' that has inherent biochemical plasticity involving multiple processes in Western Himalayas. Its potential spread is linked to site-specific micro-environment, whereby, it prefers flat valley bottoms with alluvial fills having high water availability, and has little or no altitudinal effect.


Assuntos
Ecossistema , Lepidium/fisiologia , Plantas Daninhas/fisiologia , Antioxidantes/metabolismo , Ritmo Circadiano , Clima , Transporte de Elétrons , Fluorescência , Gases/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Umidade , Lepidium/genética , Fotossíntese , Complexo de Proteína do Fotossistema II/metabolismo , Pigmentos Biológicos/metabolismo , Folhas de Planta/fisiologia , Plantas Daninhas/genética , Teoria Quântica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Pressão de Vapor
2.
Bioorg Med Chem ; 17(9): 3229-56, 2009 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19299148

RESUMO

Malaria is a major public health problem mainly due to the development of resistance by the most lethal causative parasitic species, Plasmodium falciparum to the mainstay drugs like chloroquine. New drugs with unique structures and mechanism of action are urgently required to treat sensitive and drug-resistant strains of malaria. Historically, compounds containing novel structure from natural origin represent a major source for the discovery and development of new drugs for several diseases. This review presents recent advances in antimalarial drug discovery from natural sources, including plant extracts, and compounds isolated from plants, bacteria, fungi and marine organisms. These compounds offer new and novel scaffolds for development as antimalarials. The literature from 1998 to October 2008 is reviewed. The review present literature compilation from plant and marine extracts, alkaloids (naphthylisoquinolines, bisbenzylisoquinolines, protoberberines and aporphines, indoles, manzamines, and miscellaneous alkaloids) terpenes (sesquiterpenes, triterpenes, diterpenes, and miscellaneous terpenes) quassinoids, flavonoids, limonoids, chalcones, peptides, xanthones, quinones and coumarines, and miscellaneous antimalarials from nature. The review also provides an outlook to recent semisynthetic approaches to antimalarial drugs discovered from natural sources.


Assuntos
Antimaláricos/química , Antimaláricos/farmacologia , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Sequência de Aminoácidos , Animais , Antimaláricos/isolamento & purificação , Produtos Biológicos/isolamento & purificação , Descoberta de Drogas , Dados de Sequência Molecular , Extratos Vegetais/isolamento & purificação , Plasmodium/efeitos dos fármacos
3.
AACE Clin Case Rep ; 5(2): e138-e141, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31967019

RESUMO

OBJECTIVE: To help clinicians identify and treat patients with tumor-induced osteomalacia (TIO) resulting from a phosphaturic mesenchymal tumor, mixed connective tissue variant (PMTMCT). METHODS: Describe the history, presentation, laboratory findings, diagnostic studies, treatment, and literature review. RESULTS: A 58-year-old female with no significant past medical history presents with ongoing multiple bone pain for years. She had a bone scan showing multiple focal areas of increased uptake involving bilateral ribs, distal right tibia, and left femoral neck, representing previously healed fractures. Her bilateral lower-extremity magnetic resonance imaging showed stress fractures of the anteromedial cortex, right tibia, and the left femoral neck. Phosphorus was noted to be 1.9 mg/dL (normal range, 2.0 to 4.0 mg/dL), and alkaline phosphatase was 179 U/L (normal range, 25 to 110 U/L). Tubular maximum re-absorption of phosphate to glomerular filtration rate ratio was 0.438, which was low. An outside physician initiated patient on teriparatide, which showed bone mineral density improvement after 1 year, and then the teriparatide was stopped. Later, she developed a nontraumatic pubic ramus fracture; teriparatide was resumed. While on teriparatide, she developed several new rib fractures. Due to declining phosphorus levels, further investigation led to an elevated fibroblast growth factor 23 (FGF-23) level of 243 RU/mL (normal, <50 RU/mL). TIO was strongly suspected, and a nuclear medicine positron emission tomography/computed tomography trunk with 68Ga-1,4,7,10-tetraazacyclododecane 1,4,7,10-tetraacetic acid tyrosine-3-octreotate (i.e., 68Ga-DOTATATE) showed a right heel soft-tissue nodule. Fine-needle aspiration biopsy was performed, confirming PMTMCT, positive for FGF-23 mRNA. After surgery, her symptoms resolved and her phosphorus normalized. CONCLUSION: TIO is a rare paraneoplastic syndrome characterized by bone pain, muscle weakness, and fractures associated with persistent hypophosphatemia. Clinicians now have new imaging tools to help identify and treat patients with PMTMCT.

4.
Plant Physiol Biochem ; 112: 29-44, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28033539

RESUMO

The structural and physico-chemical properties that account for the multi-functionality of dehydrins remain largely unknown. In this study, we identified, sequenced and cloned a stress regulated cDNA encoding a dehydrin-like boiling stable protein (designated as wBsSRP; wheat boiling stable stress responsive protein) from drought stressed seedlings of drought tolerant cultivar of wheat (PBW 175). qRT-PCR analysis documented high transcripts levels of wBsSRP during drought and cold conditions in the tolerant cv. PBW 175 as a part of adaptive response to stress while the levels were significantly lower in the sensitive cv. PBW 343. We also describe in-silico characterization and molecular modeling of wBsSRP through homology search, motif analysis, secondary structure prediction, active site prediction and 3D structure analysis. The physico-chemical properties and theoretical data of wBsSRP depicts that it is a canonical group 2 LEA protein. The recombinant wBsSRP protein when expressed in E. coli detected a specific differential band (∼11 kDa) on SDS- PAGE after IPTG induction. The functional analysis of wBsSRP in E. coli revealed that wBsSRP is essential for the survival of E. coli as well as for maintaining bacterial growth under various stress conditions. In vitro peroxidase protection assay during heat stress (50 and 100 °C) showed that in the presence of wBsSRP, peroxidase activity was significantly retained and/or increased. Based upon the findings, it is suggested that wBsSRP accentuated the effects of stress by acting as a protectant and by the stabilization of membranes, thereby contributing to the improved stress tolerance of the recombinant E. coli under various abiotic stress conditions. We suggest that these findings might provide the rationale for the mechanism of how these proteins obviate the adverse effects of dehydration stress.


Assuntos
Adaptação Fisiológica , Simulação por Computador , Secas , Temperatura Alta , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Triticum/fisiologia , Algoritmos , Sequência de Aminoácidos , Domínio Catalítico , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Escherichia coli/metabolismo , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Modelos Moleculares , Peroxidase/metabolismo , Proteínas de Plantas/química , Mapeamento de Interação de Proteínas , Reação em Cadeia da Polimerase em Tempo Real , Recombinação Genética/genética , Reprodutibilidade dos Testes , Análise de Sequência de Proteína , Solubilidade , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
5.
Plant Sci ; 250: 1-9, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27457978

RESUMO

Plutella xylostella L. is a notorious pest of cruciferous crops causing worldwide losses of $4-5 billion per year. Developing classical biological control to this pest include an introduction of host plants that act as natural enemies showing deviation from the preference-performance regimen in the evolutionary ecology of plant-insect interactions. The present study was designed to understand the role of glucosinolate-myrosinase system during P. xylostella interactions with a novel host. Adult moth preference and larval performance study were conducted on a novel host Lepidium latifolium L. (LL) that has high sinigrin content and was compared with its laboratory host Arabidopsis thaliana (AT). The glucosinolate-myrosinase system was studied in a time course experiment during larval feeding in choice and no-choice experiments. Adult moths visit and prefers LL over AT for oviposition. Conversely, LL leaves were not preferred and proved detrimental for P. xylostella larvae. Aliphatic and indolic glucosinolates were found to decrease significantly (p≤0.05) in AT during initial 12h of P. xylostella challenge, whereas, they were not affected in LL. Also, MYB transcription factor expression and myrosinase activity in LL do not suggest a typical host response to a specialist insect. This preference-performance mismatch of P. xylostella on LL mediated by glucosinolate pattern suggests that this novel plant could be utilized in P. xylostella management.


Assuntos
Arabidopsis/química , Glucosinolatos/metabolismo , Glicosídeo Hidrolases/metabolismo , Lepidium/química , Mariposas/fisiologia , Proteínas de Plantas/metabolismo , Animais , Arabidopsis/enzimologia , Preferências Alimentares , Larva/crescimento & desenvolvimento , Larva/fisiologia , Lepidium/enzimologia , Mariposas/crescimento & desenvolvimento , Oviposição
6.
J Agric Food Chem ; 63(47): 10218-26, 2015 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-26527478

RESUMO

Myrosinase (ExPASy entry EC 3.2.1.147) is involved in the hydrolysis of glucosinolates to isothiocyanates, nitriles, and thiocyanates that are responsible for various ecological and health benefits. Myrosinase was purified from the leaves of Lepidium latifolium, a high-altitude plant, to homogeneity in a three-step purification process. Purified enzyme exists as dimer in native form (∼160 kDa) with a subunit size of ∼70 kDa. The enzyme exhibited maximum activity at pH 6.0 and 50 °C. With sinigrin as substrate, the enzyme showed Km and Vmax values of 171 ± 23 µM and 0.302 µmol min(-1) mg(-1), respectively. The enzyme was found to be redox-regulated, with an increase in Vmax and Kcat in the presence of GSH. Reduced forms of the enzyme were found to be more active. This thiol-regulated kinetic behavior of myrosinase signifies enzyme's strategy to fine-tune its activity in different redox environments, thus regulating its biological effects.


Assuntos
Glicosídeo Hidrolases/química , Glicosídeo Hidrolases/isolamento & purificação , Lepidium/enzimologia , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Glicosídeo Hidrolases/metabolismo , Cinética , Lepidium/química , Peso Molecular , Oxirredução , Proteínas de Plantas/metabolismo , Isoformas de Proteínas/química , Isoformas de Proteínas/isolamento & purificação , Isoformas de Proteínas/metabolismo
7.
PLoS One ; 8(8): e69112, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23936316

RESUMO

Lepidium latifolium Linn. (perennial pepperweed) is one of the preferred phytofoods among cold arid region of Ladakh, India and its leaves contribute significantly to people's diet. This study was conducted to determine its nutritive value and antioxidant activity. Plant samples from three different locations were selected in the present study. Results showed that this plant is an excellent source of glucosinolates, notably sinigrin that is present in very high amount (∼70-90%). Its value ranged from 149 to 199 µg per g fresh weight. Fatty acid composition analysis showed that its leaves were abundant in unsaturated fatty acids, specifically linolenic acid (18∶3) whose percentage is about 50%. Higher glucose and crude protein along with higher nitrogen to sulfur ratio, supplements the nutritive value of this plant. Based on total phenol, flavanoids, free radical scavenging activity and DNA protective activity showed that this ecotype of perennial pepperweed contains high antioxidant properties. The percentage inhibition for O2(-) scavenging activity ranged from 41.3% to 83.9%. Higher content of phenols (26.89 to 50.51 mg gallic acid equivalents per g dry weight) and flavanoids (38.66 to 76.00 mg quercetin equivalents per g dry weight) in leaves could be responsible for the free radical scavenging activity of this plant. Depending upon the location of the plants, variations were observed in different activities. Based on the systematic evaluation in this study, preparations of Lepidium latifolium from Ladakh can be promoted as substitute to dietary requirements.


Assuntos
Antioxidantes/farmacologia , Lepidium/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Raízes de Plantas/química , Ácidos Graxos/análise , Sequestradores de Radicais Livres/farmacologia , Cromatografia Gasosa-Espectrometria de Massas , Glucosinolatos/análise
8.
Indian J Anaesth ; 55(6): 563-6, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22223898

RESUMO

BACKGROUND: Bispectral index monitoring system (BIS) is one of the several systems used to measure the effects of anaesthetic and sedative drugs on the brain and to track changes in the patient's level of sedation and hypnosis. BIS monitoring provides information clinically relevant to the adjustment of dosages of sedating medication. It can help the nursing personnel in preventing under- and over sedation among intensive care unit (ICU) patients. OBJECTIVE: The present study was conducted to assess the knowledge of nursing personnel working in the ICU regarding BIS. METHODS: Fifty-four subjects participated in the study. A structured questionnaire was developed to assess the knowledge of the nursing personnel regarding BIS. Focus group discussions were held among the nursing personnel to know their views regarding BIS. RESULTS: Mean age (years) of the subjects was 30.7±7.19 (21-47) years, with a female preponderance. Although the use of BIS in ICU is not common, majority (94.44%) were aware of BIS and its purpose. 79.62% of the subjects knew about its implication in patient care. The mean knowledge score of the subjects was 11.87±2.43 (maximum score being 15). CONCLUSION: There exists an awareness among the critical care nursing staff in our institution regarding BIS and its clinical implications. Its use in the critical care setting may benefit the patients in terms of providing optimal sedation.

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