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1.
Environ Sci Pollut Res Int ; 29(13): 19337-19351, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34714476

RESUMO

Climate change, conventional agricultural management practices, and increasing water scarcity pose a major threat to agricultural production and biodiversity as well as environmental sustainability. Climate-smart agriculture (CSA) is recognized as an efficient, sustainable, and feasible agricultural system that plays a vital role in addressing the potential impacts of climate change in Pakistan. First-hand information was collected from 450 farm households in 24 villages from Okara, Sahiwal, and Khanewal irrigation divisions, having various wheat-based cropping systems of Pakistan. This includes rice-wheat (RW), maize-wheat (MW), and cotton-wheat (CW) cropping systems in the Lower Bari Doab Canal (LBDC) irrigation system. This study estimated and compared the sustainability and efficiency analysis of CSA and conventional agricultural practices. This study also estimated the impact of water-smart practices of the CSA, technical training, and groundwater quality on agricultural production by using production function and bootstrap truncated regression. The findings of this study revealed that adopters of CSA of the wheat-based cropping systems have higher economic benefits and improved resource use efficiencies compared to the conventional farmers. The findings of the study also revealed the increased efficiency of CSA adopters over other two systems in CW cropping system. The water-smart practices of CSA, access to credit, technical training, use of groundwater of varying quality, and other inputs also showed variations in the agricultural production and resource use efficiency. It has been concluded that farmers can earn more profit, save inputs (such as water), and increase their production by adopting water-smart practices of CSA. Hence, the government and other relevant institutions should devise and implement policies that adequately addressed the importance and enhance the use of water-smart practices of CSA in Punjab and beyond.


Assuntos
Agricultura , Fazendeiros , Mudança Climática , Fazendas , Humanos , Paquistão
2.
Data Brief ; 36: 107021, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33937455

RESUMO

Social correspondence is one of the most significant columns that the public dependent on. Notably, language is the best way to communicate and associate with one another both verbally and nonverbally. There is a persistent communication gap among deaf and non-deaf communities because non-deaf people have less understanding of sign languages. Every region/country has its sign language. In Pakistan, the sign language of Urdu is a visual gesture language that is being used for communication among deaf peoples. However, the dataset of Pakistan Sign Language (PSL) is not available publicly. The dataset of PSL has been generated by acquiring images of different hand configurations through a webcam. In this work, 40 images of each hand configuration with multiple orientations have been captured. In addition, we developed, an interactive android mobile application based on machine learning that minimized the communication barrier between the deaf and non-deaf communities by using the PSL dataset. The android application recognizes the Urdu alphabet from input hand configuration.

3.
J Anal Toxicol ; 45(6): 581-592, 2021 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32886782

RESUMO

Drugs of abuse and medication reconciliation testing can benefit from analysis methods capable of detecting a broader range of drug classes and analytes. Mass spectrometry analysis of a wide variety of commonly prescribed medications and over-the-counter drugs per sample also allows for application of a drug-drug interaction (DDI) algorithm to detect adverse drug reactions. In order to prevent adulteration of commonly collected clinical samples such as urine, dried blood spots (DBS) present a reliable alternative. A novel method is described for qualitative and quantitative multiplex analysis of 230 parent drugs, 30 illicit drugs and 43 confirmatory metabolites by HPLC-MS-MS This method is applicable to DBS specimens collected by volumetric absorptive microsamplers and confirmable in urine specimens. A patient cohort (n = 67) providing simultaneous urine specimens and DBS resulted in 100% positive predictive values of medications or illicits confirmed by detection of a parent drug and/or its metabolite during routine medication adherence analysis. An additional 5,508 DBS specimens screened (n = 5,575) showed 5,428 (97%) with an inconsistent positive compared to the provided medication list (including caffeine, cotinine or ethanol metabolites), 29 (0.5%) with no medication list and no unexpected positive results (consistent negative) and 22 (0.4%) showed all positive results matching the provided medication list (consistent positive). A DDI algorithm applied to all positive results revealed 17% with serious and 56% with moderate DDI warnings. Comprehensive DBS analysis proves a reliable alternative to urine drug testing for extended medication reconciliation, with the added advantage of detecting DDIs.


Assuntos
Drogas Ilícitas , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Teste em Amostras de Sangue Seco , Humanos , Detecção do Abuso de Substâncias
5.
Clin Med (Lond) ; 13(2): 136-40, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23681859

RESUMO

Erectile dysfunction (ED) affects millions of men worldwide with implications that go far beyond sexual activity. ED is now recognised as an early marker of cardiovascular disease, diabetes mellitus (DM) and depression. The risk factors that are associated with ED (sedentary lifestyle, obesity, smoking, hypercholesterolaemia and the metabolic syndrome) are very similar to those for cardiovascular disease (CVD). Arguably, the awareness of ED as a symptomatic entity in the post-Viagra™ age is on the rise. Nevertheless, ED is commonly missed when evaluating patients in the hospital setting, either because of lack of consideration or awareness, or through simple embarrassment (of both clinician and patient). This article provides an overview of the aetiology, assessment and importance of ED and hopes to promote its consideration in day-to-day clinical practice.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Disfunção Erétil/tratamento farmacológico , Disfunção Erétil/etiologia , Consumo de Bebidas Alcoólicas/efeitos adversos , Doenças Cardiovasculares/complicações , Depressão/complicações , Disfunção Erétil/complicações , Disfunção Erétil/diagnóstico , Exercício Físico , Humanos , Masculino , Obesidade/complicações , Fumar/efeitos adversos
7.
Ann Neurol ; 72(4): 564-70, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23109151

RESUMO

OBJECTIVE: Deposition of the amyloid-ß (Aß) peptide in neuritic plaques is a requirement for the diagnosis of Alzheimer disease (AD). Although the continued development of in vivo imaging agents such as Pittsburgh compound B (PiB) is promising, the diagnosis of AD is still challenging. This can be partially attributed to our lack of a detailed understanding of the interrelationship between the various pools and species of Aß and other common indices of AD pathology. We hypothesized that recent advances in our ability to accurately measure Aß postmortem (for example, using PiB), could form the basis of a simple means to deliver an accurate AD diagnosis. METHODS: We conducted a comprehensive analysis of the amount of Aß40 and Aß42 in increasingly insoluble fractions, oligomeric Aß, and fibrillar Aß (as defined by PiB binding), as well as plaques (diffuse and neuritic), and neurofibrillary tangles in autopsy specimens from age-matched, cognitively normal controls (n = 23) and AD (n = 22) cases, across multiple brain regions. RESULTS: Both PiB binding and the amount of sodium dodecyl sulfate (SDS)-soluble Aß were able to predict disease status; however, SDS-soluble Aß was a better measure. Oligomeric Aß was not a predictor of disease status. PiB binding was strongly related to plaque count, although diffuse plaques were a stronger correlate than neuritic plaques. INTERPRETATION: Although postmortem PiB binding was somewhat useful in distinguishing AD from control cases, SDS-soluble Aß measured by standard immunoassay was substantially better. These findings have important implications for the development of imaging-based biomarkers of AD.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/genética , Compostos de Anilina , Compostos Radiofarmacêuticos , Tiazóis , Idoso de 80 Anos ou mais , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/metabolismo , Autopsia , Biomarcadores , Encéfalo/patologia , Química Encefálica , Feminino , Humanos , Masculino , Emaranhados Neurofibrilares/genética , Emaranhados Neurofibrilares/patologia , Testes Neuropsicológicos , Placa Amiloide/metabolismo , Valor Preditivo dos Testes , Cintilografia , Dodecilsulfato de Sódio/química , Solubilidade , Tensoativos/química
8.
J Alzheimers Dis ; 32(1): 127-38, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22766739

RESUMO

The development of imaging reagents is of considerable interest in the Alzheimer's disease (AD) field. Some of these, such as Pittsburgh Compound B (PiB), were designed to bind to the amyloid-ß peptide (Aß), the major component of amyloid deposits in the AD brain. Although these agents were designed for imaging amyloid deposits in vivo, a major avenue of evaluation relies on postmortem cross validation with established indices of AD pathology. In this study, we evaluated changes in the postmortem binding of PiB and its relationship to other aspects of Aß-related pathology in a series of AD cases and age-matched controls. We also examined cases of preclinical AD (PCAD) and amnestic mild cognitive impairment (MCI), both considered early points in the AD continuum. PiB binding was found to increase with the progression of the disease and paralleled increases in the less soluble forms of Aß, including SDS-stable Aß oligomers. Increased PiB binding and its relationship to Aß was only significant in a brain region vulnerable to the development of AD pathology (the superior and middle temporal gyri) but not in an unaffected region (cerebellum). This implies that the amyloid deposited in disease-affected regions may possess fundamental, brain region specific characteristics that may not as yet be fully appreciated. These data support the idea that PiB is a useful diagnostic tool for AD, particularly in the early stage of the disease, and also show that PiB could be a useful agent for the discovery of novel disease-related properties of amyloid.


Assuntos
Doença de Alzheimer/metabolismo , Compostos de Anilina/metabolismo , Encéfalo/metabolismo , Tiazóis/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Encéfalo/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/psicologia , Progressão da Doença , Ensaio de Imunoadsorção Enzimática , Feminino , Demência Frontotemporal/metabolismo , Demência Frontotemporal/patologia , Humanos , Masculino , Testes Neuropsicológicos , Tamanho do Órgão , Tomografia por Emissão de Pósitrons
9.
Aging Cell ; 10(1): 103-13, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20969723

RESUMO

Recent reports demonstrate that the activation and interaction of the protease calpain (CP) and the protein phosphatase calcineurin (CN) are elevated in the late stages of Alzheimer's disease (AD). However, the extent to which CPs and CN interact during earlier stages of disease progression remains unknown. Here, we investigated CP and CN protein levels in cytosolic, nuclear, and membrane fractions prepared from human postmortem hippocampal tissue from aged non-demented subjects, and subjects diagnosed with mild cognitive impairment (MCI). The results revealed a parallel increase in CP I and the 48 kDa CN-Aα (ΔCN-Aα48) proteolytic fragment in cytosolic fractions during MCI. In primary rat hippocampal cultures, CP-dependent proteolysis and activation of CN was stimulated by application of oligomeric Aß((1-42)) peptides. Deleterious effects of Aß on neuronal morphology were reduced by blockade of either CP or CN. NMDA-type glutamate receptors, which help regulate cognition and neuronal viability, and are modulated by CPs and CN, were also investigated in human hippocampus. Relative to controls, MCI subjects showed significantly greater proteolytic levels of the NR2B subunit. Within subjects, the extent of NR2B proteolysis was strongly correlated with the generation of ΔCN-Aα48 in the cytosol. A similar proteolytic pattern for NR2B was also observed in primary rat hippocampal cultures treated with oligomeric Aß and prevented by inhibition of CP or CN. Together, the results demonstrate that the activation and interaction of CPs and CN are increased early in cognitive decline associated with AD and may help drive other pathologic processes during disease progression.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/farmacologia , Calcineurina , Calpaína , Transtornos Cognitivos/fisiopatologia , Inibidores Enzimáticos/farmacologia , Hipocampo/fisiopatologia , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/farmacologia , Idoso de 80 Anos ou mais , Envelhecimento/genética , Envelhecimento/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/genética , Animais , Calcineurina/metabolismo , Inibidores de Calcineurina , Cálcio/metabolismo , Calpaína/antagonistas & inibidores , Calpaína/metabolismo , Estudos de Casos e Controles , Técnicas de Cultura de Células , Fracionamento Celular , Transtornos Cognitivos/genética , Transtornos Cognitivos/metabolismo , Progressão da Doença , Ativação Enzimática , Feminino , Ácido Glutâmico/metabolismo , Hipocampo/metabolismo , Humanos , Masculino , Fragmentos de Peptídeos/genética , Ratos , Receptores de N-Metil-D-Aspartato/metabolismo , Estudos Retrospectivos , Transdução de Sinais
10.
J Neurosci ; 29(41): 12957-69, 2009 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-19828810

RESUMO

Upon activation by calcineurin, the nuclear factor of activated T-cells (NFAT) translocates to the nucleus and guides the transcription of numerous molecules involved in inflammation and Ca(2+) dysregulation, both of which are prominent features of Alzheimer's disease (AD). However, NFAT signaling in AD remains relatively uninvestigated. Using isolated cytosolic and nuclear fractions prepared from rapid-autopsy postmortem human brain tissue, we show that NFATs 1 and 3 shifted to nuclear compartments in the hippocampus at different stages of neuropathology and cognitive decline, whereas NFAT2 remained unchanged. NFAT1 exhibited greater association with isolated nuclear fractions in subjects with mild cognitive impairment (MCI), whereas NFAT3 showed a strong nuclear bias in subjects with severe dementia and AD. Similar to NFAT1, calcineurin-Aalpha also exhibited a nuclear bias in the early stages of cognitive decline. But, unlike NFAT1 and similar to NFAT3, the nuclear bias for calcineurin became more pronounced as cognition worsened. Changes in calcineurin/NFAT3 were directly correlated to soluble amyloid-beta (Abeta((1-42))) levels in postmortem hippocampus, and oligomeric Abeta, in particular, robustly stimulated NFAT activation in primary rat astrocyte cultures. Oligomeric Abeta also caused a significant reduction in excitatory amino acid transporter 2 (EAAT2) protein levels in astrocyte cultures, which was blocked by NFAT inhibition. Moreover, inhibition of astrocytic NFAT activity in mixed cultures ameliorated Abeta-dependent elevations in glutamate and neuronal death. The results suggest that NFAT signaling is selectively altered in AD and may play an important role in driving Abeta-mediated neurodegeneration.


Assuntos
Calcineurina/metabolismo , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/metabolismo , Fatores de Transcrição NFATC/metabolismo , Transdução de Sinais/fisiologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/complicações , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/farmacologia , Análise de Variância , Animais , Astrócitos/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Células Cultivadas , Transtornos Cognitivos/patologia , Embrião de Mamíferos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína Glial Fibrilar Ácida/metabolismo , Ácido Glutâmico/metabolismo , Proteínas de Fluorescência Verde/genética , Hipocampo/citologia , Humanos , Masculino , Fragmentos de Peptídeos/farmacologia , Transporte Proteico/genética , Ratos , Transfecção
11.
Chembiochem ; 9(14): 2295-304, 2008 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-18756551

RESUMO

Mithramycin is an antitumor drug produced by Streptomyces argillaceus. It consists of a tricyclic aglycone and five deoxyhexoses that form a disaccharide and a trisaccharide chain, which are important for target interaction and therefore for the antitumor activity. Using a combinatorial biosynthesis approach, we have generated nine mithramycin derivatives, seven of which are new compounds, with alterations in the glycosylation pattern. The wild-type S. argillaceus strain and the mutant S. argillaceus M7U1, which has altered D-oliose biosynthesis, were used as hosts to express various "sugar plasmids", each one directing the biosynthesis of a different deoxyhexose. The newly formed compounds were purified and characterized by MS and NMR. Compared to mithramycin, they contained different sugar substitutions in the second (D-olivose, D-mycarose, or D-boivinose instead of D-oliose) and third (D-digitoxose instead of D-mycarose) sugar units of the trisaccharide as well as in the first (D-amicetose instead of D-olivose) sugar unit of the disaccharide. All compounds showed antitumor activity against different tumor cell lines. Structure-activity relationships are discussed on the basis of the number and type of deoxyhexoses present in these mithramycin derivatives.


Assuntos
Antibacterianos/biossíntese , Antibacterianos/química , Antineoplásicos/química , Antineoplásicos/metabolismo , Desenho de Fármacos , Plicamicina/biossíntese , Plicamicina/química , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Carboidratos/biossíntese , Linhagem Celular Tumoral , Técnicas de Química Combinatória , Glicosilação , Humanos , Mutação , Plicamicina/farmacologia , Streptomyces/genética , Streptomyces/metabolismo , Trissacarídeos/química
12.
J Nat Prod ; 71(9): 1569-73, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18666798

RESUMO

Two new anticancer antibiotics of the angucycline class, moromycins A and B (1, 2), along with the known microbial metabolites saquayamycin B (3) and fridamycin D (4) were isolated from the ethyl acetate extract of a culture broth of the terrestrial Streptomyces sp. KY002. The structures consist of a tetrangomycin core and various C- and O-glycosidically linked deoxysugars. The chemical structures of the new secondary metabolites were elucidated by 1D and 2D NMR and by mass spectrometry. Moromycin B (2) showed significant cytotoxicity against H-460 human lung cancer and MCF-7 human breast cancer cells.


Assuntos
Antraquinonas/isolamento & purificação , Antraquinonas/farmacologia , Antibióticos Antineoplásicos/isolamento & purificação , Antibióticos Antineoplásicos/farmacologia , Streptomyces/química , Antraquinonas/química , Antibióticos Antineoplásicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Kentucky , Testes de Sensibilidade Microbiana , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
13.
J Nat Prod ; 71(2): 199-207, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18197601

RESUMO

Plasmid pLNBIV was used to overexpress the biosynthetic pathway of nucleoside-diphosphate (NDP)-activated l-digitoxose in the mithramycin producer Streptomyces argillaceus. This led to a "flooding" of the biosynthetic pathway of the antitumor drug mithramycin (MTM) with NDP-activated deoxysugars, which do not normally occur in the pathway, and consequently to the production of the four new mithramycin derivatives 1- 4 with altered saccharide patterns. Their structures reflect that NDP sugars produced by pLNBIV, namely, l-digitoxose and its biosynthetic intermediates, influenced the glycosyl transfer to positions B, D, and E, while positions A and C remained unaffected. All four new structures have unique, previously not found sugar decoration patterns, which arise from either overcoming the substrate specificity or inhibition of certain glycosyltransferases (GTs) of the MTM pathway with the foreign NDP sugars expressed by pLNBIV. An apoptosis TUNEL (=terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) assay revealed that compounds 1 (demycarosyl-3D-beta- d-digitoxosyl-MTM) and 3 (deoliosyl-3C-beta- d-mycarosyl-MTM) show improved activity (64.8 +/- 2% and 50.3 +/- 2.5% induction of apoptosis, respectively) against the estrogen receptor (ER)-positive human breast cancer cell line MCF-7 compared with the parent drug MTM (37.8 +/- 2.5% induction of apoptosis). In addition, compounds 1 and 4 (3A-deolivosyl-MTM) show significant effects on the ER-negative human breast cancer cell line MDA-231 (63.6 +/- 2% and 12.6 +/- 2.5% induction of apoptosis, respectively), which is not inhibited by the parent drug MTM itself (2.6 +/- 1.5% induction of apoptosis), but for which chemotherapeutic agents are urgently needed.


Assuntos
Antibióticos Antineoplásicos , Plicamicina , Antibióticos Antineoplásicos/biossíntese , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Técnicas de Química Combinatória , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Estrutura Molecular , Plicamicina/análogos & derivados , Plicamicina/biossíntese , Plicamicina/química , Plicamicina/farmacologia , Streptomyces/química , Streptomyces/genética , Relação Estrutura-Atividade , Células Tumorais Cultivadas
14.
Appl Environ Microbiol ; 72(10): 6644-52, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17021216

RESUMO

Combinatorial biosynthesis was applied to Streptomyces deoxysugar biosynthesis genes in order to reconstitute "unnatural natural gene clusters" for the biosynthesis of four D-deoxysugars (D-olivose, D-oliose, D-digitoxose, and D-boivinose). Expression of these gene clusters in Streptomyces albus 16F4 was used to prove the functionality of the designed clusters through the generation of glycosylated tetracenomycins. Three glycosylated tetracenomycins were generated and characterized, two of which (D-digitoxosyl-tetracenomycin C and D-boivinosyl-tetracenocmycin C) were novel compounds. The constructed gene clusters may be used to increase the capabilities of microorganisms to synthesize new deoxysugars and therefore to produce new glycosylated bioactive compounds.


Assuntos
Família Multigênica , Streptomyces griseus/metabolismo , Antineoplásicos/metabolismo , Clonagem Molecular , Desoxiaçúcares/biossíntese , Hexoses/biossíntese , Dados de Sequência Molecular , Naftacenos/metabolismo , Streptomyces griseus/química , Streptomyces griseus/genética
16.
Appl Microbiol Biotechnol ; 73(1): 122-31, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16810496

RESUMO

Glycosylation pattern in cosmomycins is a distinctive feature among anthracyclines. These antitumor compounds possess two trisaccharide chains attached at C-7 and C-10, each of them with structural variability, mainly at the distal deoxysugar moieties. We have characterized a 14-kb chromosomal region from Streptomyces olindensis containing 13 genes involved in cosmomycin biosynthesis. Two of the genes, cosG and cosK, coding for glycosyltransferase were inactivated with the generation of five new derivatives. Structural elucidation of these compounds showed altered glycosylation patterns indicating the capability of both glycosyltransferases of transferring deoxysugars to both sides of the aglycone and the flexibility of CosK with respect to the deoxysugar donor. A model is proposed for the glycosylation steps during cosmomycins biosynthesis.


Assuntos
Antraciclinas/química , Antraciclinas/metabolismo , Glicosiltransferases/genética , Streptomyces/metabolismo , Proteínas de Bactérias/genética , DNA Bacteriano/química , DNA Bacteriano/genética , Deleção de Genes , Ordem dos Genes , Teste de Complementação Genética , Glicosilação , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Estrutura Molecular , Análise de Sequência de DNA , Streptomyces/enzimologia , Streptomyces/genética
17.
Nat Prod Res ; 18(5): 465-71, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15248616

RESUMO

Two new isoflavones 1 and 2 along with eleven known compounds 3-13, have been isolated for the first time from the rhizomes of Iris soforana. The structures of these compounds were determined on the basis of spectroscopic methods and found to be 5,3'-dihydroxy-4'-methoxy-6,7-methylenedioxyisoflavone (1) (Soforanarin A), and 5,7,5'-trimethoxy-6,3',4'-trihydroxyisoflavone (2) (Soforanarin B).


Assuntos
Iris , Isoflavonas/química , Fitoterapia , Extratos Vegetais/química , Humanos , Espectroscopia de Ressonância Magnética , Raízes de Plantas
18.
Biochemistry ; 43(18): 5562-73, 2004 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-15122922

RESUMO

In the frame of a research aimed at the detailed structural characterization of human calcium-binding proteins of the EF-hand family, the solution structure of human alpha-parvalbumin has been solved by NMR and refined with the help of substitution of the Ca(2+) ion in the EF site with the paramagnetic Dy(3+) ion. A simple (1)H-(15)N HSQC spectrum allowed the NH assignments based on the properties of Dy(3+). This allowed us to exploit pseudocontact shifts and residual dipolar couplings for solution structure refinement. The backbone and heavy atom RMSD are 0.55 +/- 0.08 and 1.02 +/- 0.08 A, respectively, and decrease to 0.39 +/- 0.05 and 0.90 +/- 0.06 A upon refinement with paramagnetism-based restraints. The RMSD for the metal itself in the EF site in the refined structure is 0.26 +/- 0.12 A. Backbone NH R(1), R(2), and NOE measured at two temperatures show the protein to be relatively rigid. The NH orientations are well determined by the paramagnetism-based restraints. This allows us to detect small but significant local structural differences with the orthologue protein from rat, whose X-ray structure is available at 2.0 A resolution. All differences are related to local changes in the amino acidic composition.


Assuntos
Proteínas de Ligação ao Cálcio/química , Ressonância Magnética Nuclear Biomolecular/métodos , Parvalbuminas/química , Amidas/química , Animais , Anisotropia , Isótopos de Carbono , Cristalografia por Raios X , Disprósio/química , Motivos EF Hand , Humanos , Modelos Moleculares , Isótopos de Nitrogênio , Conformação Proteica , Isoformas de Proteínas/química , Prótons , Ratos , Soluções
19.
J Ethnopharmacol ; 86(2-3): 177-80, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12738083

RESUMO

The anti-inflammatory activity of nine isoflavonoids 5,7-dihydroxy-3-(3'-hydroxy-4',5'dimethoxy)-8-methoxy-4H-1-benzopyran-4-one 1, 5,7-dihydroxy-3-(3'-hydroxyl-4', 5'-dimethoxy)-6-methoxy-4H-1-benzopyran-4-one 2, 5, 7-dihydroxy-3-(4'-hydroxy)-6-methoxy-4H-1-benzopyrane-4-one 3, 5-hydroxy-3-(4'-hydroxy)-6,7-methylenedioxy-4H-1-benzopyran-4-one 4, 5-hydroxy-3-(4'-methoxy)-6,7-methylenedioxy-4H-1-benzopyran-4-one 5, 5-methoxy-3-(4'-hydroxy)-6,7-methyenedioxy-4H-1-benzopyran-4-one 6, 5,7-dihydroxy-3-(3'-hydroxy-4'-methoxy)-6-methoxy-4H-1-benzopyran-4-one 7, 5,7-dihydroxy-3-(3'-methoxy-4'-hydroxy)-6-methoxy-4H-1-benzopyran-4-one 8, and isopeonol 9 determined by a spectrophotometric assay using the activated human neutrophils. These isoflavonoids were isolated from an important folkloric medicinal plant Irsa (Iris germanica L.), a member of the family Iridaceae. Structures of these compounds were identified by spectral comparison with the reported data and active members of this group adds into the growing number of non-steroidal anti-inflammatory agents.


Assuntos
Anti-Inflamatórios não Esteroides , Gênero Iris , Isoflavonas , Medicina Tradicional , Preparações de Plantas , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Anti-Inflamatórios não Esteroides/farmacologia , Humanos , Isoflavonas/química , Isoflavonas/isolamento & purificação , Isoflavonas/farmacologia , Neutrófilos/efeitos dos fármacos , Preparações de Plantas/química , Preparações de Plantas/isolamento & purificação , Preparações de Plantas/farmacologia , Rizoma , Espectrofotometria , Relação Estrutura-Atividade
20.
Chem Pharm Bull (Tokyo) ; 50(8): 1100-2, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12192144

RESUMO

Four isoflavone glycosides were isolated from the rhizomes of Iris germanica. Compounds 1 and 2 are new, while compounds 3 and 4 are known isoflavone glycosides. These compounds were identified as iriskashmirianin 4'-O-beta-D-glucoside (1), nigricin 4'-O-beta-D-glucoside (2), irilone 4'-O-beta-D-glucoside (3) and iridin (4). Their structures were determined with the help of spectroscopic methods.


Assuntos
Glicosídeos/isolamento & purificação , Gênero Iris/química , Isoflavonas/isolamento & purificação , Rizoma , Glicosídeos/química , Isoflavonas/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Rizoma/química
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