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1.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469288

RESUMO

Abstract Increased anxiety and depressive symptoms have reported to be its association with long term illness. Because of having unwanted effects of newly available drugs, patients administering anxiolytic drugs usually discontinue the treatment before they are completely recovered. Therefore, there is a serious need to develop new anxiolytic drugs. The anxiolytic effect of hydro-alcoholic extract of Agaricus blazei in animal models was assessed. 24 male mice (Mus musculus genus) were included in the study. Four groups were prepared and each group contained six animals. The groups were vehicle control, positive control (diazepam 1.0 mg/kg, i.p.) as well as two treatment groups receiving Agaricus blazei hydro-alcoholic extract at a dose of 136.50 mg/kg and 273.0 mg/kg orally. The Marble burying test, Nestlet shredding test and Light and Dark box test used to assess anxiolytic activity. Mice administered with diazepam 1.0 mg/kg, i.p. while hydro-alcoholic extract of AbM (136.50 and 273.0 mg/kg, respectively) was administered via oral route which exhibited marked reduction in number of marbles-burying as compared to vehicle control group. Mice administered with diazepam 1.0 mg/kg, i.p. and Oral administration of hydro-alcoholic extract of AbM (136.50 and 273.0 mg/kg, respectively) exhibited significant decrease in nestlet shredding in comparison to vehicle control group. The oral administration of hydro-alcoholic extract at a dose of 136.5mg/kg and 273mg/kg showed elevation in time spent in light box and was comparable to standard treated group while time spent by mice following oral administration of hydro-alcoholic extract of Agaricus blazei at a dose of 273.0 mg/kg also showed elevation and was found to be more near to standard treated group (diazepam 1 mg/kg, i.p.).


Resumo O aumento da ansiedade e dos sintomas depressivos têm relatado sua associação com doenças de longa duração. Por causa dos efeitos indesejáveis dos novos medicamentos disponíveis, os pacientes que administram medicamentos ansiolíticos geralmente interrompem o tratamento antes de estarem completamente recuperados. Portanto, há uma necessidade séria de desenvolver novos medicamentos ansiolíticos. Foi avaliado o efeito ansiolítico do extrato hidroalcoólico de Agaricus blazei em modelos animais. Vinte e quatro camundongos machos (gênero Mus musculus) foram incluídos no estudo. Quatro grupos foram preparados, e cada grupo continha seis animais. Os grupos foram controle de veículo, controle positivo (diazepam 1,0 mg/kg, i.p.), bem como dois grupos de tratamento recebendo extrato hidroalcoólico de Agaricus blazei na dose de 136,50 mg/kg e 273,0 mg/kg por via oral. O teste de enterrar Marble, o teste de retalhamento Nestlet e o teste de caixa clara e escura são usados para avaliar a atividade ansiolítica. Camundongos foram administrados com diazepam 1,0 mg/kg, i.p., enquanto o extrato hidroalcoólico de AbM (136,50 e 273,0 mg/kg, respectivamente) foi administrado por via oral, que exibiu redução acentuada no número de mármores enterrados em comparação com o grupo de controle de veículo. Camundongos administrados com diazepam 1,0 mg/kg, i.p. e a administração oral de extrato hidroalcoólico de AbM (136,50 e 273,0 mg/kg, respectivamente) exibiu diminuição significativa na trituração de ninhos em comparação ao grupo de controle de veículo. A administração oral de extrato hidroalcoólico na dose de 136,5mg/kg e 273mg/kg mostrou elevação no tempo gasto na caixa de luz e foi comparável ao grupo tratado padrão, enquanto o tempo gasto por camundongos após a administração oral de extrato hidroalcoólico de Agaricus blazei na dose de 273,0 mg/kg também mostrou elevação e foi mais próximo do grupo tratado padrão (diazepam 1 mg/kg, ip).

2.
Braz. j. biol ; 84: e252575, 2024. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355869

RESUMO

Abstract Increased anxiety and depressive symptoms have reported to be its association with long term illness. Because of having unwanted effects of newly available drugs, patients administering anxiolytic drugs usually discontinue the treatment before they are completely recovered. Therefore, there is a serious need to develop new anxiolytic drugs. The anxiolytic effect of hydro-alcoholic extract of Agaricus blazei in animal models was assessed. 24 male mice (Mus musculus genus) were included in the study. Four groups were prepared and each group contained six animals. The groups were vehicle control, positive control (diazepam 1.0 mg/kg, i.p.) as well as two treatment groups receiving Agaricus blazei hydro-alcoholic extract at a dose of 136.50 mg/kg and 273.0 mg/kg orally. The Marble burying test, Nestlet shredding test and Light and Dark box test used to assess anxiolytic activity. Mice administered with diazepam 1.0 mg/kg, i.p. while hydro-alcoholic extract of AbM (136.50 and 273.0 mg/kg, respectively) was administered via oral route which exhibited marked reduction in number of marbles-burying as compared to vehicle control group. Mice administered with diazepam 1.0 mg/kg, i.p. and Oral administration of hydro-alcoholic extract of AbM (136.50 and 273.0 mg/kg, respectively) exhibited significant decrease in nestlet shredding in comparison to vehicle control group. The oral administration of hydro-alcoholic extract at a dose of 136.5mg/kg and 273mg/kg showed elevation in time spent in light box and was comparable to standard treated group while time spent by mice following oral administration of hydro-alcoholic extract of Agaricus blazei at a dose of 273.0 mg/kg also showed elevation and was found to be more near to standard treated group (diazepam 1 mg/kg, i.p.).


Resumo O aumento da ansiedade e dos sintomas depressivos têm relatado sua associação com doenças de longa duração. Por causa dos efeitos indesejáveis dos novos medicamentos disponíveis, os pacientes que administram medicamentos ansiolíticos geralmente interrompem o tratamento antes de estarem completamente recuperados. Portanto, há uma necessidade séria de desenvolver novos medicamentos ansiolíticos. Foi avaliado o efeito ansiolítico do extrato hidroalcoólico de Agaricus blazei em modelos animais. Vinte e quatro camundongos machos (gênero Mus musculus) foram incluídos no estudo. Quatro grupos foram preparados, e cada grupo continha seis animais. Os grupos foram controle de veículo, controle positivo (diazepam 1,0 mg/kg, i.p.), bem como dois grupos de tratamento recebendo extrato hidroalcoólico de Agaricus blazei na dose de 136,50 mg/kg e 273,0 mg/kg por via oral. O teste de enterrar Marble, o teste de retalhamento Nestlet e o teste de caixa clara e escura são usados ​​para avaliar a atividade ansiolítica. Camundongos foram administrados com diazepam 1,0 mg/kg, i.p., enquanto o extrato hidroalcoólico de AbM (136,50 e 273,0 mg/kg, respectivamente) foi administrado por via oral, que exibiu redução acentuada no número de mármores enterrados em comparação com o grupo de controle de veículo. Camundongos administrados com diazepam 1,0 mg/kg, i.p. e a administração oral de extrato hidroalcoólico de AbM (136,50 e 273,0 mg/kg, respectivamente) exibiu diminuição significativa na trituração de ninhos em comparação ao grupo de controle de veículo. A administração oral de extrato hidroalcoólico na dose de 136,5mg/kg e 273mg/kg mostrou elevação no tempo gasto na caixa de luz e foi comparável ao grupo tratado padrão, enquanto o tempo gasto por camundongos após a administração oral de extrato hidroalcoólico de Agaricus blazei na dose de 273,0 mg/kg também mostrou elevação e foi mais próximo do grupo tratado padrão (diazepam 1 mg/kg, ip).


Assuntos
Animais , Masculino , Coelhos , Agaricus , Comportamento Exploratório , Modelos Animais de Doenças
3.
Braz J Biol ; 84: e252575, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34932635

RESUMO

Increased anxiety and depressive symptoms have reported to be its association with long term illness. Because of having unwanted effects of newly available drugs, patients administering anxiolytic drugs usually discontinue the treatment before they are completely recovered. Therefore, there is a serious need to develop new anxiolytic drugs. The anxiolytic effect of hydro-alcoholic extract of Agaricus blazei in animal models was assessed. 24 male mice (Mus musculus genus) were included in the study. Four groups were prepared and each group contained six animals. The groups were vehicle control, positive control (diazepam 1.0 mg/kg, i.p.) as well as two treatment groups receiving Agaricus blazei hydro-alcoholic extract at a dose of 136.50 mg/kg and 273.0 mg/kg orally. The Marble burying test, Nestlet shredding test and Light and Dark box test used to assess anxiolytic activity. Mice administered with diazepam 1.0 mg/kg, i.p. while hydro-alcoholic extract of AbM (136.50 and 273.0 mg/kg, respectively) was administered via oral route which exhibited marked reduction in number of marbles-burying as compared to vehicle control group. Mice administered with diazepam 1.0 mg/kg, i.p. and Oral administration of hydro-alcoholic extract of AbM (136.50 and 273.0 mg/kg, respectively) exhibited significant decrease in nestlet shredding in comparison to vehicle control group. The oral administration of hydro-alcoholic extract at a dose of 136.5mg/kg and 273mg/kg showed elevation in time spent in light box and was comparable to standard treated group while time spent by mice following oral administration of hydro-alcoholic extract of Agaricus blazei at a dose of 273.0 mg/kg also showed elevation and was found to be more near to standard treated group (diazepam 1 mg/kg, i.p.).


Assuntos
Agaricus , Comportamento Exploratório , Animais , Modelos Animais de Doenças , Masculino , Camundongos
4.
J Postgrad Med ; 2018 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-30588925

RESUMO

INTRODUCTION: Operative duration is an important but under-studied predictor of mortality in emergency laparotomies. AIMS AND OBJECTIVES: The primary objective of this study was to quantify the effect of duration of emergency laparotomy in children on mortality; and to identify a rough cut-off duration of laparotomy to serve as a guide so that a laparotomy can be planned to optimize pediatric surgical patient outcome. MATERIALS AND METHODS: This is a prospective study conducted in a government tertiary teaching institution over a period of 24 months. All children in the age group of 5-10 years presenting in the emergency department with Pediatric Risk of Mortality III score ≤8, undergoing emergency laparotomy in emergency operation theater, were included. OBSERVATIONS AND RESULTS: In all, 213 children were included in the study. The mean time from presentation to shifting to the operating room was 3.7 h. The mean operative duration was 108 min. The mean operative time in survived patients was 102 min as compared to 135 min in expired patients (P < 0.05). The 30-day in-hospital mortality rate was 17.4%. After application of binary logistic regression analysis, it was found that time to laparotomy and operative duration were significant risk factors (<0.05) predicting post-operative mortality. Kaplan-Meier survival curve showed a decrease at a mean weighted operative duration of approximately 100 min. Receiver operating characteristic curve analysis yielded operative duration of 123.5 min at which Youden's index maximized. CONCLUSION: This 100-min duration of laparotomy might appear a long duration but in casualty setup of a government hospital with limited resources, there are so many hurdles for optimal working that completion of an emergency laparotomy in children in 100 min can be considered a realistic target for improving post-operative outcome. At an operative duration of <123.50 min, mortality rates within acceptable limits can be achieved.

5.
J Postgrad Med ; 64(3): 183-185, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29992914

RESUMO

We report a case of incarcerated left indirect inguinal hernia in a male child which on exploration revealed the presence of free air and fecal matter containing fluid in the hernial sac. This is the second reported case of the presence of cecal perforation in left Amyand's hernia in pediatric age group and unique in the sense of the form of abnormal anatomy encountered per-operatively.


Assuntos
Hérnia Inguinal/complicações , Perfuração Intestinal/etiologia , Retropneumoperitônio/etiologia , Ceco , Pré-Escolar , Humanos , Masculino
6.
J Coll Physicians Surg Pak ; 26(3): 191-4, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26975949

RESUMO

OBJECTIVE: To determine the correlation between CRP (C-reactive protein) and Waist to Hip Ratio (WHR) among over weight and obese patients with normal blood pressure. STUDY DESIGN: An analytical study. PLACE AND DURATION OF STUDY: Medical indoor and outpatient clinics of Mayo Hospital, Lahore, from March to August 2013. METHODOLOGY: Willing patients with Body Mass Index (BMI) of > 23 kg/m2, normal blood pressures, and age between 18 - 65 years were inducted in the study. Patients with signs of fluid retention, collagen vascular disease, CAD, on corticosteroids, immunomodulators or lipid lowering medications, hypertensives and febrile patients were excluded. Patients were considered to be at low risk for cardiovascular events if WHR among males and females was < 0.95 and < 0.80, respectively. Similarly, males and females with WHR > 1 and > 0.85, respectively were taken as high risk. Levels in-between these ranges were taken as moderate risk. Data was analyzed on SPSS 15. Descriptive statistics were determined. The p-value was calculated by ANOVA and independent sample t-test among males and females respectively, to compare WHR in relation to different CRP levels and < 0.05 was taken as significant. RESULTS: There were 34 male and 74 female patients. The gender-wise mean WHR did not show statistically significant difference categorized CRP levels (p=0.072 in male, and 0.052 in females). There was an increasing trend in CRP levels as WHR increased among females, but this was statistically insignificant (p=0.05). CONCLUSION: Although the impact of central obesity on cardiac health is well known, however, WHR alone is an unreliable indicator of systemic inflammation and raised CRP level.


Assuntos
Pressão Sanguínea/fisiologia , Proteína C-Reativa/metabolismo , Obesidade/sangue , Relação Cintura-Quadril , Adulto , Idoso , Glicemia/análise , Índice de Massa Corporal , Proteína C-Reativa/análise , Feminino , Humanos , Hipertensão , Mediadores da Inflamação/sangue , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Obesidade/metabolismo , Fatores de Risco
7.
Rev Sci Instrum ; 84(5): 056113, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23742611

RESUMO

We performed thermal analysis for our previously reported [M. Iqbal, K. Masood, M. Rafiq, M. A. Chaudhry, and F. Aleem, Rev. Sci. Instrum. 74, 4616 (2003)], long linear filament electron gun assembly using ANSYS software. The source was set under a thermal load of 3000 °C, to evaluate temperature distribution, thermal strain, and heat flux at various components of the gun. We calculated the maximum heat flux (9.0 W/mm(2)) that produced a thermal strain of 0.05 at the focusing electrodes. However, the minimum value of the heat flux (0.3 W/mm(2)) was at the anode electrodes which correspond to a negligible thermal strain. The gun was validated experimentally showing a uniform cross section of the beam at the molybdenum work plate comparable to the size of the filament. Our experimental and theoretical results are in agreement. The gun had been in continuous operation for several hours at high temperatures without any thermal run-out.

8.
J Mol Graph Model ; 28(8): 792-8, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20338793

RESUMO

A pharmacophore model was developed based on three structurally diverse urease inhibitors by using the GASP program. This model comprises the positions and tolerance for two acceptor atoms (AA1 and AA2), one donor atom (DA1), and one hydrophobic center (HYP1). This derived phamacophore model was employed to screen an in-house database of organic compounds. Hits obtained were evaluated by molecular docking using GOLD software. On the basis of ligand- and structural-based predictions, an in vitro testing of short-listed compounds was conducted and a novel class of urease inhibitors (2-aminothiophines) was identified. The potent in vitro activity and selectivity of these compounds, along with their non-toxic nature against the plant cells indicated that they can serve as leads for solving urease-associated health and agriculture problems.


Assuntos
Urease/antagonistas & inibidores , Urease/química , Animais , Simulação por Computador , Desenho de Fármacos , Humanos , Ligantes , Modelos Moleculares , Estrutura Molecular , Software , Relação Estrutura-Atividade
9.
J Asian Nat Prod Res ; 11(11): 933-9, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20183256

RESUMO

The mechanism of inhibition of the alpha-chymotrypsin enzyme by two lignans of the fused bistetrahydrofuran series, epiexcelsin (1) and 5'-demethoxyepiexcelsin (2), which were isolated from the Commiphora mukul Engl., was investigated. Lineweaver-Burk and Dixon plots and their secondary replots showed that these compounds were noncompetitive inhibitors of the enzyme. K(i) values for 1 and 2 were found to be 22.29 +/- 0.015 and 336.30 +/- 0.053 microM, respectively.


Assuntos
Quimotripsina/antagonistas & inibidores , Lignanas/isolamento & purificação , Lignanas/farmacocinética , Magnoliaceae/química , Plantas Medicinais/química , Lignanas/química , Matemática , Estrutura Molecular , Paquistão
10.
Bioorg Med Chem ; 16(6): 3456-61, 2008 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-18280742

RESUMO

A 3D-QSAR study has been performed on thirty (30) bis-coumarine derivatives to correlate their chemical structures with their observed urease inhibitory activity. Due to the absence of information on their active mechanism, comparative molecular field analysis (CoMFA) was used in the study. Two different properties: steric, electrostatic, assumed to cover the major contributions to ligand binding, were used to generate the 3D-QSAR model. Significant cross-validated correlation coefficients q(2) (0.558) and r(2) (0.992) for CoMFA were obtained, indicating the statistical significance of this class of compounds. The red electrostatic contour map highlighting those portion of compounds which may be interacting with nickel metal center in the active site of urease; while the blue contour map indicates positively charged groups in the ligands have improved biological activity and thus lower the IC(50)s. The steric contour map shows that bulkier substitutions at the 'R' position are detrimental to ligand receptor interaction. Actual urease inhibitory activities of this class and the predicted values were in good agreement with the experimental results. Moreover, from the contour maps, the key features vital to ligand binding have been identified, which are important for us to trace the important properties and gain insight into the potential mechanisms of intermolecular interactions between the ligand and receptor.


Assuntos
Antineoplásicos/química , Cumarínicos/química , Cumarínicos/farmacologia , Relação Quantitativa Estrutura-Atividade , Urease/antagonistas & inibidores , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Cumarínicos/síntese química , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/síntese química , Feminino , Humanos , Modelos Moleculares
11.
Biochem Biophys Res Commun ; 334(1): 276-87, 2005 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-16108094

RESUMO

The withanolides 1-3 and 4-5 isolated from Ajuga bracteosa and Withania somnifera, respectively, inhibited acetylcholinesterase (AChE, EC 3.1.1.7) and butyrylcholinesterase (BChE, EC 3.1.1.8) enzymes in a concentration-dependent fashion with IC50 values ranging between 20.5 and 49,2 microm and 29.0 and 85.2 microm for AChE and BChE, respectively. Lineweaver-Burk as well as Dixon plots and their secondary replots indicated that compounds 1, 3, and 5 are the linear mixed-type inhibitors of AChE, while 2 and 4 are non-competitive inhibitors of AChE with K(i) values ranging between 20.0 and 45.0 microm. All compounds were found to be non-competitive inhibitors of BChE with K(i) values ranging between 27.7 and 90.6 microm. Molecular docking study revealed that all the ligands are completely buried inside the aromatic gorge of AChE, while compounds 1, 3, and 5 extend up to the catalytic triad. A comparison of the docking results showed that all ligands generally adopt the same binding mode and lie parallel to the surface of the gorge. The superposition of the docked structures demonstrated that the non-flexible skeleton of the ligands always penetrates the aromatic gorge through the six-membered ring A, allowing their simultaneous interaction with more than one subsite of the active center. The affinity of ligands with AChE was found to be the cumulative effects of number of hydrophobic contacts and hydrogen bonding. Furthermore, all compounds also displayed dose-dependent (0.005-1.0 mg/mL) spasmolytic and Ca2+ antagonistic potentials in isolated rabbit jejunum preparations, compound 4 being the most active with an ED50 value of 0.09 +/- 0.001 mg/mL and 0.22 +/- 0.01 microg/mL on spontaneous and K+ -induced contractions, respectively. The cholinesterase inhibitory potential along with calcium antagonistic ability and safe profile in human neutrophil viability assay could make compounds 1-5 possible drug candidates for further study to treat Alzheimer's disease and associated problems.


Assuntos
Acetilcolinesterase/química , Cálcio/metabolismo , Ergosterol/química , Ergosterol/toxicidade , Jejuno/metabolismo , Modelos Químicos , Modelos Moleculares , Neutrófilos/efeitos dos fármacos , Animais , Sinalização do Cálcio/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Inibidores da Colinesterase/análise , Inibidores da Colinesterase/química , Inibidores da Colinesterase/toxicidade , Simulação por Computador , Relação Dose-Resposta a Droga , Ergosterol/análogos & derivados , Humanos , Jejuno/efeitos dos fármacos , Dose Letal Mediana , Modelos Biológicos , Conformação Molecular , Neutrófilos/patologia , Coelhos , Withania/metabolismo
12.
Biochem Biophys Res Commun ; 332(4): 1171-7, 2005 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16021692

RESUMO

The alkaloid juliflorine (1) from Prosopis juliflora inhibited acetylcholinesterase (AChE, EC 3.1.1.7) and butyrylcholinesterase (BChE, EC 3.1.1.8) enzymes in a concentration-dependent fashion with IC50 values 0.42 and 0.12 microM, respectively. Lineweaver-Burk as well as Dixon plots and their secondary replots indicated that the nature of inhibition was purely of non-competitive type with Ki values 0.4 and 0.1 microM, against AChE and BChE, respectively. By molecular docking studies compound 1 was found to be ideally spaced inside the aromatic gorge of AChE with rings A/B remaining at the top and rings C/D penetrating deep into the gorge, that might be due to the greater hydrophobicity of rings C/D as compared to rings A/B, allowing their simultaneous interaction with the peripheral anionic and quaternary ammonium-binding sites. The 1-AChE complex was found to be stabilized by hydrophobic contacts, hydrogen bonding, and pi-pi stacking between the compound 1 and amino acid residues of the aromatic gorge of AChE. Amino acid residues Tyr70, Asp72, Tyr121, Trp279, and Tyr334 of the peripheral anionic site (PAS) of AChE were found to be exclusively involved in the hydrophobic contacts with compound 1 that might be responsible for the competitive mode of inhibition. Compound 1 also showed dose-dependent (30-500 microg/mL) spasmolytic and Ca2+-channel blocking activities in isolated rabbit jejunum preparations. The cholinesterase inhibitory potential along with calcium-channel blocking activity of compound 1 and safe profile in human neutrophils viable assay could make it a possible drug candidate for Alzheimer's disease.


Assuntos
Alcaloides/farmacologia , Doença de Alzheimer/tratamento farmacológico , Canais de Cálcio/metabolismo , Inibidores da Colinesterase/farmacologia , Animais , Sítios de Ligação , Cálcio/metabolismo , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Humanos , Ligação de Hidrogênio , Concentração Inibidora 50 , Cinética , Modelos Químicos , Modelos Moleculares , Conformação Molecular , Neutrófilos/metabolismo , Ligação Proteica , Conformação Proteica , Torpedo , Tirosina/química
13.
Med Device Technol ; 16(4): 18-9, 21, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15941193

RESUMO

Proteins employed as diagnostic agents must be kept stable to maintain their structure and viability. Multiple strategies to address stabilisation issues are presented here.


Assuntos
Avaliação de Medicamentos/métodos , Estabilidade de Medicamentos , Armazenamento de Medicamentos/métodos , Proteínas/química , Proteínas/uso terapêutico , Garantia da Qualidade dos Cuidados de Saúde/métodos , Desnaturação Proteica , Proteínas/análise
14.
Nat Prod Res ; 19(3): 267-74, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15702640

RESUMO

Two new myrsinol-type diterpene polyesters 3,5,13,17-tetra-O-acetyl-7-O-benzoyl-15-hydroxymyrsinol (1) and 3,5,13,17-tetra-O-acetyl-7-O-butanoyl-13-hydroxymyrsinol (2), with a tricyclic carbon skeleton have been isolated from Euphorbia decipiens Boiss. & Buhse. The structure elucidation of the isolated compounds was based primarily on HREIMS, EIMS, IR, UV, ID-, and 2D-NMR analyses, including COSY, HMQC, HMBC, and NOESY correlations. Compounds 1 and 2 also showed activity against urease enzyme.


Assuntos
Diterpenos/química , Diterpenos/isolamento & purificação , Euphorbia/química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/isolamento & purificação , Inibidores Enzimáticos/farmacologia , Urease/antagonistas & inibidores
15.
Proc Natl Acad Sci U S A ; 96(20): 11416-21, 1999 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-10500191

RESUMO

The yeast and human SKP1 genes regulate the mitotic cell cycle but are not yet known to be required for meiosis. Nine Arabidopsis SKP1 homologues have been uncovered and are named ASK1 through ASK9. Here, we report the isolation and characterization of a male sterile Arabidopsis mutant and show that the mutant defect was caused by a Ds transposon insertion into the ASK1 gene. In the ask1-1 mutant, abnormal microspores exhibit a range of sizes. Furthermore, during mutant male meiosis, although homologous chromosome pairing appeared normal at metaphase I, chromosome segregation at anaphase I is unequal, and some chromosomes are abnormally extended. Therefore, in ask1-1, at least some homologues remain associated after metaphase I. In addition, immunofluorescence microscopy indicates that the mutant spindle morphology at both metaphase I and early anaphase I is normal; thus, the abnormal chromosome segregation is not likely caused by a spindle defect. Because the yeast Skp1p is required for targeting specific proteins for ubiquitin-mediated proteolysis, we propose that ASK1 controls homologue separation by degrading or otherwise removing a protein that is required directly or indirectly for homologue association before anaphase I.


Assuntos
Proteínas de Arabidopsis , Arabidopsis/genética , Proteínas de Ciclo Celular/genética , Genes de Plantas , Meiose , Sequência de Aminoácidos , Sequência de Bases , Cromossomos , Dados de Sequência Molecular , Mutação , Proteínas de Plantas/genética , Proteínas Quinases Associadas a Fase S
16.
Anal Biochem ; 241(2): 228-37, 1996 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-8921192

RESUMO

A fluorescence-based, T7 (Sequenase) dye terminator method for sequencing double-stranded DNA using strings of three contiguous hexamers as primers and single-stranded binding protein is described. In this method, the circular, supercoiled DNA vector pUC19 is first linearized with a restriction enzyme to create a sequenceable template. Sequencing is then accomplished using three cycles of "denaturation," annealing, and extension/termination. Twenty-two of 33 hexamer strings tested in a controlled study produced acceptable sequence, with read lengths varying from the mid 300s to the low 400s and a base-calling accuracy of at least 97%. To test its potential utility in directed DNA sequencing, the protocol was then used to completely sequence both strands of pUC19. For this test project, a total of 28 hexamer strings was used with an overall successful priming rate of 75%. The current protocol appears to be sufficiently robust to be used in the finishing phase of a shotgun sequencing project and is amenable to semiautomation. Prospects for using the protocol for full-scale directed sequencing as well as for full automation are discussed.


Assuntos
Análise de Sequência de DNA , Automação , Sequência de Bases , DNA , Corantes Fluorescentes , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
18.
Genome Res ; 6(1): 10-8, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8681134

RESUMO

The finishing phase of genome sequencing projects is expensive, in part, because of the cost of de novo synthesis of custom primers and the management burden associated with obtaining and using them for primer walking. One approach to reduce these high costs is the use of a presynthesized library of short oligonucleotides (8-10 bases) rather than long primers. The use of such a library eliminates the need for custom synthesis of oligonucleotides, providing the convenience of priming from any site by combining two to three short oligonucleotides to form a string with the required specificity. The first practical implementation of this strategy presented a robust protocol for using hexamer strings with radioisotopic labelling. Whereas versions of this technique have subsequently been implemented on fluorescent sequencers we felt that there was a need to develop and extensively test a protocol that consistently gave read lengths comparable to dye-terminator sequencing with longer primers. We have developed a new two-cycle fluorescent Sequenase terminator procedure for using hexamer strings. We tested this procedure using a set of 32 different 3 hexamer primer strings, each known to be functional to some degree in radioisotopic sequencing, on single-stranded M13mp18 template and ABI 373 DNA sequencers. The overall success rate of priming with these hexamer primer strings is 97% with the failure of only one string. In this case, the corresponding 18-mer primer also failed to produce usable sequence from M13mp18 template. The average read length from reactions successfully primed with the 31 different hexamer strings was 461 bases with > 99% base-calling accuracy. The current protocol is robust enough to be used in virtually any situation where primer walking on single-stranded templates is used. The success rate and read lengths make it universally applicable to the sequencing of single-stranded templates on automated sequencers. It is also amenable to automation.


Assuntos
Análise de Sequência de DNA/métodos , Automação , Composição de Bases , Sequência de Bases , Primers do DNA , DNA de Cadeia Simples , Dados de Sequência Molecular
19.
Genome ; 38(4): 786-94, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7672609

RESUMO

Genetic linkage maps of Vitis (2n = 38) have been constructed from a single interspecific hybrid grape population (60 seedlings) of 'Cayuga White' X 'Aurore'. The maps were primarily based on 422 RAPD markers but also included 16 RFLP and isozyme markers. These maps had an average distance of 6.1 cM between markers and were developed using a double-pseudotestcross strategy. The 'Cayuga White' map had 214 markers covering 1196 cM and that of 'Aurore' spanned over 1477 cM with 225 markers. The 'Cayuga White' map consisted of 20 linkage groups, whereas 22 linkage groups comprised the 'Aurore' map. The number of groups reduced to 19, as in some instances two or more groups from one parent showed homology with a single group from the other parent on the basis of markers heterozygous in both parents. Each linkage group ranged in size from 14 to 135 cM in 'Aurore' and from 14 to 124 cM in 'Cayuga White'. These maps provide enough coverage of the genome to allow quantitative trait locus analysis and map-based gene cloning.


Assuntos
Frutas/genética , Ligação Genética , Marcadores Genéticos , Sequência de Bases , Cruzamentos Genéticos , Primers do DNA , Heterozigoto , Homozigoto , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
20.
Theor Appl Genet ; 90(1): 11-6, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24173778

RESUMO

The nuclear DNA content was analyzed in Vitis species, hybrid cultivars, and genera of the Vitaceae using flow cytometry. Significant variation was found among Vitis species, hybrids, and other genera of the Vitaceae (Ampelopsis and Parthenocissus). DNA content was estimated to range from 0.98 to 1.05 pg/2C within V. labrusca (ns) and 0.86 to 1.00 pg/2C within V. vinifera (ns). Genotypes from Vitis and Parthenocissus were similar in nuclear DNA content (approximately 1.00 pg/2C) whereas they differed significantly from Ampelopsis (1.39 pg/2C). No correlation between DNA content and the center of origin of genotypes of the Vitaceae was noted. Based on the present study, the Vitis genome size is 475 Mbp, 96% of which is non-coding. Knowledge of DNA content is useful in order to understand the complexity of the Vitis genome and to establish a relationship between the genetic and physical map for map-based cloning.

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