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1.
Clin Genet ; 91(3): 470-475, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27607563

RESUMO

Dominant mutations in PIEZO2, which codes for the principal mechanotransduction channel for proprioception and touch sensation, have been found to cause different forms of distal arthrogryposis. Some observations suggest that these dominant mutations induce a gain-of-function effect on the channel. Here, we report a consanguineous family with three siblings who showed short stature, scoliosis, gross motor impairment, and a progressive form of contractures involving the distal joints that is distinct from that found in patients with dominant mutations in PIEZO2. These siblings also displayed deficits in proprioception and touch sensation. Whole-exome sequencing performed in the three affected siblings revealed the presence of a rare homozygous variant (c.2708C>G; p.S903*) in PIEZO2. This variant is predicted to disrupt PIEZO2 function by abolishing the pore domain. Sanger sequencing confirmed that all three siblings are homozygous whereas their parents and an unaffected sibling are heterozygous for this variant. Recessive mutations in PIEZO2 thus appear to cause a progressive phenotype that overlaps with, while being mostly distinct from that associated with dominant mutations in the same gene.


Assuntos
Artrogripose/genética , Contratura/genética , Canais Iônicos/genética , Propriocepção/genética , Adulto , Artrogripose/fisiopatologia , Bangladesh , Consanguinidade , Contratura/fisiopatologia , Feminino , Heterozigoto , Homozigoto , Humanos , Lactente , Masculino , Escoliose/genética , Escoliose/fisiopatologia , Irmãos , Tato/genética
2.
Indian Heart J ; 68(6): 809-815, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27931552

RESUMO

BACKGROUND: Ischemic cardiomyopathy is a growing burden in third world countries. So far, benefits of trimetazidine in this group of patients have been suggested by clinical trials mainly conducted in Europe. We evaluated the effect of trimetazidine on ischemic dilated cardiomyopathy in our population. METHODS AND RESULTS: 98 patients (aged 58.5±9.2 years), admitted with decompensated heart failure with previous history of MI and/or documentation of significant CAD with previous CAG, were chosen for the study. Patients were randomized into two groups - one provided with trimetazidine 35mg sustained released tablet, twice daily and the other with a placebo, along with other conventional medications. Patients were included if they had dilated LV (LVIDd>57mm) and left ventricular ejection fraction (LVEF) ≤40%. After 6 months, significantly higher number of patients in trimetazidine group were in NYHA class I (22% vs. 8%, p=0.03) and class II (56% vs. 34%, p=0.01); higher number of patients in placebo group were in NYHA class III class IV. Anginal episodes and use of sublingual nitrate per week were significantly lower in the trimetazidine group. Left ventricular diastolic dimension (59.7±5.2 vs. 65.1±6.1, p=0.001) was significantly different in the two groups as was the increase of LVEF (11% vs. 5.6%, p=0.001). Hospitalization for worsening heart failure was significantly lower in trimetazidine group (13 vs. 22, p=0.047). CONCLUSION: Trimetazidine seems to be beneficial in patients with ischemic dilated cardiomyopathy in South Asian population and larger scale study with extended follow-up is needed.


Assuntos
Cardiomiopatia Dilatada/tratamento farmacológico , Contração Miocárdica/fisiologia , Trimetazidina/administração & dosagem , Função Ventricular Esquerda/fisiologia , Cardiomiopatia Dilatada/fisiopatologia , Preparações de Ação Retardada , Relação Dose-Resposta a Droga , Método Duplo-Cego , Ecocardiografia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Contração Miocárdica/efeitos dos fármacos , Fatores de Tempo , Resultado do Tratamento , Vasodilatadores/administração & dosagem , Função Ventricular Esquerda/efeitos dos fármacos
3.
Environ Sci Pollut Res Int ; 23(8): 7899-910, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26762934

RESUMO

The nitrite reductase (nirS and nirK) and nitrous oxide reductase-encoding (nosZ) genes of denitrifying populations present in an agricultural grassland soil were quantified using real-time polymerase chain reaction (PCR) assays. Samples from three separate pedological depths at the chosen site were investigated: horizon A (0-10 cm), horizon B (45-55 cm), and horizon C (120-130 cm). The effect of carbon addition (treatment 1, control; treatment 2, glucose-C; treatment 3, dissolved organic carbon (DOC)) on denitrifier gene abundance and N2O and N2 fluxes was determined. In general, denitrifier abundance correlated well with flux measurements; nirS was positively correlated with N2O, and nosZ was positively correlated with N2 (P < 0.03). Denitrifier gene copy concentrations per gram of soil (GCC) varied in response to carbon type amendment (P < 0.01). Denitrifier GCCs were high (ca. 10(7)) and the bac:nirK, bac:nirS, bac:nir (T) , and bac:nosZ ratios were low (ca. 10(-1)/10) in horizon A in all three respective treatments. Glucose-C amendment favored partial denitrification, resulting in higher nir abundance and higher N2O fluxes compared to the control. DOC amendment, by contrast, resulted in relatively higher nosZ abundance and N2 emissions, thus favoring complete denitrification. We also noted soil depth directly affected bacterial, archaeal, and denitrifier abundance, possibly due to changes in soil carbon availability with depth.


Assuntos
Agricultura , Carbono/farmacologia , Solo/química , Bactérias/efeitos dos fármacos , Bactérias/genética , Desnitrificação , Pradaria , Nitrito Redutases/genética , Nitrogênio/análise , Óxido Nitroso/análise , Oxirredutases/genética , Reação em Cadeia da Polimerase em Tempo Real , Microbiologia do Solo
4.
Hum Exp Toxicol ; 35(9): 991-1004, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26519480

RESUMO

This study investigated the main target sites of chlorpyrifos (CPF), its effect on biochemical indices, and the pathological changes observed in rat liver and kidney function using gas chromatography/mass spectrometry. Adult female Wistar rats (n = 12) were randomly assigned into two groups (one control and one test group; n = 6 each). The test group received CPF via oral gavage for 21 days at 5 mg/kg daily. The distribution of CPF was determined in various organs (liver, brain, heart, lung, kidney, ovary, adipose tissue, and skeletal muscle), urine and stool samples using GCMS. Approximately 6.18% of CPF was distributed in the body tissues, and the highest CPF concentration (3.80%) was found in adipose tissue. CPF also accumulated in the liver (0.29%), brain (0.22%), kidney (0.10%), and ovary (0.03%). Approximately 83.60% of CPF was detected in the urine. CPF exposure resulted in a significant increase in plasma transaminases, alkaline phosphatase, and total bilirubin levels, a significant reduction in total protein levels and an altered lipid profile. Oxidative stress due to CPF administration was also evidenced by a significant increase in liver malondialdehyde levels. The detrimental effects of CPF on kidney function consisted of a significant increase in plasma urea and creatinine levels. Liver and kidney histology confirmed the observed biochemical changes. In conclusion, CPF bioaccumulates over time and exerts toxic effects on animals.


Assuntos
Clorpirifos/toxicidade , Poluentes Ambientais/toxicidade , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Clorpirifos/farmacocinética , Poluentes Ambientais/farmacocinética , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Rim/metabolismo , Testes de Função Renal , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Testes de Função Hepática , Ratos Wistar , Distribuição Tecidual
5.
Genet Mol Res ; 14(4): 17007-18, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26681048

RESUMO

Disease susceptibility and genetic variability in 10 eggplant genotypes were studied after inoculating Phomopsis vexans under confined field conditions. Random amplified polymorphic DNA (RAPD) markers were used to assess genetic variation and relationships among eggplant genotypes. The disease index of leaves ranged 0.208-13.79%, while fruit infection ranged 2.15-42.76%. Two varieties, Dohazari G and Laffa S, were found to be susceptible, 6 were moderately resistant, 1 was moderately susceptible, and BAU Begun-1 was resistant to P. vexans. Amplification of genomic DNA by using 3 RAPD primers produced 20 bands: 14 (70%) were polymorphic and 6 (30%) were monomorphic. The highest intra-variety similarity indices values were found in ISD 006, Ishurdi L, Jessore L, and BAU Begun-1 (100%), while the lowest was in Dohazari G (90%). The lowest genetic distance (0.0513) and the highest genetic identity (0.9500) were observed between the ISD 006 and Ishurdi L combinations. A comparatively higher genetic distance (0.3724) and the lowest genetic identity (0.6891) were observed between the ISD 006 and Dohazari G combinations. A dendogram was constructed based on Nei's genetic distance, which produced 2 main clusters of the genotypes - Cluster I: ISD 006, Ishurdi L, Marich begun L, BAU Begun-1, Marich begun S, and Chega and Cluster 2: Laffa S, Dohazari G, Jessore L, and Singhnath. Genetic variation and its relationship with disease susceptibility were assessed using RAPD markers, to develop disease-resistant varieties and improve eggplant crops.


Assuntos
Marcadores Genéticos , Predisposição Genética para Doença , Variação Genética , Doenças das Plantas/genética , Solanum melongena/genética , Ascomicetos , Resistência à Doença/genética , Evolução Molecular , Filogenia , Doenças das Plantas/microbiologia , Reação em Cadeia da Polimerase , Técnica de Amplificação ao Acaso de DNA Polimórfico , Solanum melongena/classificação
6.
Mymensingh Med J ; 24(4): 710-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26620008

RESUMO

It is suggested in different studies that gender has a great impact on the distribution of risk factors of stroke. This study aims at determining the gender differences in risk factors of acute ischemic stroke among male and female patients. Data extracted for this study were taken from a case control study which was carried out in the departments of Neurology and Medicine of Dhaka Medical College Hospital (DMCH) and Shaheed Suhrawardy Medical College Hospital (ShSMCH) Dhaka from July 2009 to June 2011. We collected data of 125 patients with ischemic stroke and 129 healthy controls from the primary source. All secondary data were divided on the basis of gender. Among all male respondents 70 stroke patients were considered as case and 72 healthy respondents were considered as control and in female group 55 were stroke patients (case) and 57 were healthy control. Risk factors of stroke for male and female were evaluated separately. After multivariate analysis ever smoking (both present and ex smoker) (adj. OR 3.799, 95% CI 1.416, 10.19), diabetes mellitus (adj. OR 5.687, 95% CI 1.99, 16.26), hypertension (adj. OR 18.53, 95% CI 6.43, 53.4) and total cholesterol (adj. OR 1.017, 95% CI 1.01, 1.03) were found significant predictors for stroke in male whereas diabetes mellitus (adj. OR 6.989, 95% CI 1.54, 31.64), hypertension (adj. OR 17.85, 95% CI 5.1, 62.38), serum low density lipoprotein (LDL) (adj. OR 1.04, 95% CI 1.013, 1.07) and serum triglyceride (TG) (adj. OR 1.012, 95% CI 1.004, 1.02) were found significant in female. Besides taking the controlling measure for hypertension and diabetes mellitus, life style modification is an important factor to prevent stroke in both sexes.


Assuntos
Isquemia Encefálica/etiologia , Acidente Vascular Cerebral/etiologia , Idoso , Bangladesh , Estudos de Casos e Controles , Colesterol/sangue , Complicações do Diabetes/etiologia , Feminino , Humanos , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Caracteres Sexuais
8.
Rev Sci Instrum ; 86(12): 126114, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26724095

RESUMO

Grating based X-ray phase contrast imaging is on the verge of being applied in clinical settings. To achieve this goal, compact setups with high sensitivity and dose efficiency are necessary. Both can be increased by eliminating unwanted absorption in the beam path, which is mainly due to the grating substrates. Fabrication of gratings via deep X-ray lithography can address this issue by replacing the commonly used silicon substrate with materials with lower X-ray absorption that fulfill certain boundary conditions. Gratings were produced on both graphite and polymer substrates without compromising on structure quality. These gratings were tested in a three-grating setup with a source operated at 40 kVp and lead to an increase in the detector photon count rate of almost a factor of 4 compared to a set of gratings on silicon substrates. As the visibility was hardly affected, this corresponds to a significant increase in sensitivity and therefore dose efficiency.


Assuntos
Artefatos , Refratometria/instrumentação , Difração de Raios X/instrumentação , Absorção de Radiação , Desenho de Equipamento , Análise de Falha de Equipamento , Doses de Radiação , Reprodutibilidade dos Testes , Espalhamento de Radiação , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/instrumentação , Raios X
9.
Bangladesh Med Res Counc Bull ; 41(1): 19-23, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27089630

RESUMO

Achilles tendon is the tendon connecting the heel with the calf muscles. Tendo-achilles injury (TAI) in players is common in games. The frequency of TAI is unknown and aetiology is controversial: The present descriptive cross-sectional study was done to determine the prevalence of TAI and associated factors contributing to it in football, cricket and badminton. From January to June 2012, male players (n = 131), age -17-35 years, were selected by purposive sampling technique from renowned sporting clubs at Dhaka, Bangladesh. TAI was diagnosed through structured questionnaire and interviewing the respondents. The analysis by Statistical Package for Social Sciences (SPSS) programme revealed that 11.5% players suffered from TAI, i.e. prevalence was 115 per 1000 respondents. Most injuries (70/131; 53.4%) occurred in the playground and (59/131; 45.3%) happened in practice field. Injuries among the players of third division were higher, i.e. about 36% (p = 0.000). TAI was significantly dependent on occupation (p = 0.046), BMI (p = 0.008), divisional status (p = 0.023), game type (p = 0.043), ground condition (p = 0.05) and injury severity (p = 0.000). The injured players referred for treatment to the physiotherapist was highest (9/15, i.e. 60%) followed by the physicians (5/15, i.e. 33%) (p = 0.000). The associations of TAI with various factors were discussed suggesting effective measures be taken and treatment, particularly physiotherapy, be given to injured players. However, there is a need of team work with sports medicine specialist also to enable the injured players to continue their professional games.


Assuntos
Tendão do Calcâneo/lesões , Traumatismos em Atletas/epidemiologia , Futebol Americano/lesões , Esportes com Raquete/lesões , Adolescente , Adulto , Traumatismos em Atletas/terapia , Bangladesh , Estudos Transversais , Humanos , Entrevistas como Assunto , Masculino , Modalidades de Fisioterapia , Prevalência , Fatores de Risco , Inquéritos e Questionários
11.
Niger Postgrad Med J ; 20(2): 116-9, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23959352

RESUMO

AIMS AND OBJECTIVES: The study seeks to determine the advantages of using the pistol-grip syringe holder in the performance of FNAB over the use of direct finger grip method. PATIENTS AND METHODS: The skin is cleaned with gauze soaked in methylated spirit and the lump is located and firmly held between the thumb and fore finger of the free hand. The syringe is held by the out side of the barrel or by pistol-grip, and the needle tip pushed into the lesion. The plunger is partially retracted, creating a negative pressure. The cutting edge of the needle tip frees the cells inside the lesion which are sucked into the fine bore of the needle. The contents of the needle are then emptied on a microscopic slide and thinly smeared. The slides are then fixed in alcohol and later stained. These were examined under the microscope and a comparison between the aspirations using pistol-grip and direct finger grip was made. RESULTS: A total of 266 cases of FNABs were carried out from 1st January to 31st December, 2008. There were 89 breast cases out of which 42 (47%) had pistol-grip method and 47 (53%) had direct finger grip method; 74 thyroid cases out of which 28 (38%) were pistol-grip and 46 (62%) were direct finger grip cases; 56 cases of lymph node FNABs of which 18(32%) and 38 (68%) had pistol-grip and direct finger grip methods respectively. There were 23 cases of salivary gland FNABs having 8 (35%) and 15 (65%) as pistol-grip and direct finger grip methods respectively. Marked cellularity was observed in the majority of cases using both methods of FNABs. CONCLUSION: This study has shown that the use of pistol-grip syringe holder in the performance of FNABs has no significant advantage compared to the direct finger grip method.


Assuntos
Biópsia por Agulha Fina/instrumentação , Equipamentos para Diagnóstico , Desenho de Equipamento , Neoplasias/diagnóstico , Manejo de Espécimes/instrumentação , Seringas , Biópsia por Agulha Fina/métodos , Mama/patologia , Pesquisa Comparativa da Efetividade , Humanos , Linfonodos/patologia , Reprodutibilidade dos Testes , Glândulas Salivares/patologia , Manejo de Espécimes/métodos , Glândula Tireoide/patologia
12.
J Contam Hydrol ; 152: 70-81, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23891966

RESUMO

Identification of specific landscape areas with high and low groundwater denitrification potential is critical for improved management of agricultural nitrogen (N) export to ground and surface waters and indirect nitrous oxide (N2O) emissions. Denitrification products together with concurrent hydrogeochemical properties were analysed over two years at three depths at two low (L) and two high (H) permeability agricultural sites in Ireland. Mean N2O-N at H sites were significantly higher than L sites, and decreased with depth. Conversely, excess N2-N were significantly higher at L sites than H sites and did not vary with depth. Denitrification was a significant pathway of nitrate (NO3⁻-N) reduction at L sites but not at H sites, reducing 46-77% and 4-8% of delivered N with resulting mean NO3⁻-N concentrations of 1-4 and 12-15 mg N L⁻¹ at L and H sites, respectively. Mean N2O-N emission factors (EF5g) were higher than the most recent Intergovernmental Panel on Climate Change (IPCC, 2006) default value and more similar to the older IPCC (1997) values. Recharge during winter increased N2O but decreased excess dinitrogen (excess N2-N) at both sites, probably due to increased dissolved oxygen (DO) coupled with low groundwater temperatures. Denitrifier functional genes were similar at all sites and depths. Data showed that highly favourable conditions prevailed for denitrification to occur--multiple electron donors, low redox potential (Eh<100 mV), low DO (<2 mg L⁻¹), low permeability (k(s)<0.005 m·d⁻¹) and a shallow unsaturated zone (<2 m). Quantification of excess N2-N in groundwater helps to close N balances at the local, regional and global scales.


Assuntos
Água Subterrânea/análise , Óxido Nitroso/química , Desnitrificação , Água Subterrânea/química , Hidrologia
13.
Mymensingh Med J ; 22(2): 313-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23715354

RESUMO

This cross sectional study was done to observe the prevalence of emotional and behavioral disorders in children with epilepsy, in the Department of Psychiatry, Pediatrics and Neurology, of Bangabandhu Sheikh Mujib Medical University (BSMMU), Bangladesh from July 2007 to June 2008. In this study, information about psychiatric disorders of 50 epileptic children, age ranging from 5-17 years with mean±SD (11.1±1.43) years, and 50 age, sex and socio-demographic status matched controls children (age ranging from 5-18 years with mean±SD (11.6±1.82) years were enrolled by parent, teacher and self version of Development And Well-Being Assessment (DAWBA) (Validated Bangla Version). Emotional disorders are more prevalent than behavioral disorders among epileptic children. Forty four percent (44%) of children with epilepsy had psychiatric disorder and this rate was significantly higher than that of healthy control (p>0.05). Disorders include major depressive disorder (20%), obsessive compulsive disorder (25%), other anxiety disorders (25%), specific phobia (15%), separation anxiety disorder (10%) and panic disorder with agoraphobia (5%).


Assuntos
Transtornos do Comportamento Infantil/psicologia , Epilepsia/psicologia , Transtornos Mentais/psicologia , Adolescente , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica
14.
Mymensingh Med J ; 22(2): 325-30, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23715356

RESUMO

The present study has examined the association between ischemic stroke and hyperuricemia in Bangladeshi population. This age and sex matched case control study was carried out in the Department of Neurology, Bangabandhu Sheikh Mujib Medical University (BSMMU), Dhaka, Bangladesh during the period of January 2007 to December 2008. A total of 120 subjects were included in this study, among them 60 were cases and another 60 were controls. Data were collected purposively. Multiple logistic regressions were done to identify the risk factors for ischemic stroke. In this study 68.3% were male and 31.7% were female in both the groups. Male and female ratio of stroke patients was 2.16:1. Mean±SD of serum uric acid level of case and control group was 4.94±1.76 and 3.72±1.09 respectively. Among the case group 76.7% had normal and 23.3% had abnormal serum uric acid level. On the other hand, 93.3% respondents of control group had normal and 6.7% had abnormal serum uric acid (SUA) level. Significant differences was found between case and control group in term of SUA level (p<0.05). Since SUA level is a quantitative numerical variable, an increase in 1mg/dl has a 47.0% (95% CI 1.0% to 2.16%) increase in odds ratio (OR) of having ischemic stroke. This 47.0% is obtained by taking OR for uric acid-1. Elevated serum uric acid level is not significant for ischemic stroke among the Bangladeshi population.


Assuntos
Isquemia Encefálica/sangue , Acidente Vascular Cerebral/sangue , Ácido Úrico/sangue , Idoso , Comorbidade , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
15.
J Environ Manage ; 111: 208-12, 2012 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-22922500

RESUMO

The objective of the study was to evaluate the different headspace equilibration methods for the quantification of dissolved greenhouse gases in groundwater. Groundwater samples were collected from wells with contrasting hydrogeochemical properties and degassed using the headspace equilibration method. One hundred samples from each well were randomly selected, treatments were applied and headspace gases analysed by gas chromatography. Headspace equilibration treatments varied helium (He):water ratio, shaking time and standing time. Mean groundwater N(2)O, CO(2) and CH(4) concentrations were 0.024 mg N L(-1), 13.71 mg C L(-1) and 1.63 µg C L(-1), respectively. All treatments were found to significantly influence dissolved gas concentrations. Considerable differences in the optimal He:water ratio and standing time were observed between the three gases. For N(2)O, CO(2) and CH(4) the optimum operating points for He:water ratio was 4.4:1, 3:1 and 3.4:1; shaking time was 13, 12 and 13 min; and standing time was 63, 17 and 108 min, respectively. The headspace equilibration method needs to be harmonised to ensure comparability between studies. The experiment reveals that He:water ratio 3:1 and shaking time 13 min give better estimation of dissolved gases than any lower or higher ratios and shaking times. The standing time 63, 17 and 108 min should be applied for N(2)O, CO(2) and CH(4), respectively.


Assuntos
Cromatografia Gasosa/métodos , Monitoramento Ambiental/métodos , Gases/análise , Água Subterrânea/análise , Hélio/análise , Efeito Estufa , Irlanda
16.
Artigo em Inglês | MEDLINE | ID: mdl-23983317

RESUMO

Free radicals and reactive oxygen species (ROS) have been implicated in contributing to the processes of aging and disease. In an effort to combat free radical activity, scientists are studying the effects of increasing individuals' antioxidant levels through diet and dietary supplements. Honey appears to act as an antioxidant in more ways than one. In the body, honey can mop up free radicals and contribute to better health. Various antioxidant activity methods have been used to measure and compare the antioxidant activity of honey. In recent years, DPPH (Diphenyl-1-picrylhydrazyl), FRAP (Ferric Reducing Antioxidant Power), ORAC (The Oxygen Radical Absorbance Capacity), ABTS [2, 2-azinobis (3ehtylbenzothiazoline-6-sulfonic acid) diamonium salt], TEAC [6-hydroxy-2, 5, 7, 8-tetramethylchroman-2-carboxylic acid (Trolox)-equivalent antioxidant capacity] assays have been used to evaluate antioxidant activity of honey. The antioxidant activity of honey is also measured by ascorbic acid content and different enzyme assays like Catalase (CAT), Glutathione Peroxidase (GPO), Superoxide Dismutase (SOD). Among the different methods available, methods that have been validated, standardized and widely reported are recommended.


Assuntos
Antioxidantes/farmacologia , Mel/análise , Ácido Ascórbico/farmacologia , Radicais Livres/metabolismo , Humanos
18.
J Food Sci ; 76(6): C921-8, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22417491

RESUMO

The phenolic acid and flavonoid contents of Malaysian Tualang, Gelam, and Borneo tropical honeys were compared to those of Manuka honey. Ferric reducing/antioxidant power assay (FRAP) and the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical-scavenging activities were also quantified. All honey extracts exhibited high phenolic contents (15.21 ± 0.51- 42.23 ± 0.64 mg/kg), flavonoid contents (11.52 ± 0.27- 25.31 ± 0.37 mg/kg), FRAP values (892.15 ± 4.97- 363.38 ± 10.57 µM Fe[II]/kg), and high IC50 of DPPH radical-scavenging activities (5.24 ± 0.40- 17.51 ± 0.51 mg/mL). Total of 6 phenolic acids (gallic, syringic, benzoic, trans-cinnamic, p-coumaric, and caffeic acids) and 5 flavonoids (catechin, kaempferol, naringenin, luteolin, and apigenin) were identified. Among the Malaysian honey samples, Tualang honey had the highest contents of phenolics, and flavonoids, and DPPH radical-scavenging activities. We conclude that among Malaysian honey samples, Tualang honey is the richest in phenolic acids, and flavonoid compounds, which have strong free radical-scavenging activities.


Assuntos
Antioxidantes/análise , Ácidos Carboxílicos/análise , Mel/análise , Fenóis/análise , Antioxidantes/química , Ácidos Carboxílicos/química , Cromatografia Líquida de Alta Pressão , Flavonoides/análise , Flavonoides/química , Sequestradores de Radicais Livres/análise , Sequestradores de Radicais Livres/química , Malásia , Fenóis/química , Extração em Fase Sólida , Espectrofotometria
19.
Food Chem Toxicol ; 48(8-9): 2388-92, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20595027

RESUMO

5-Hydroxymethylfurfural (HMF) content is an indicator of the purity of honey. High concentrations of HMF in honey indicate overheating, poor storage conditions and old honey. This study investigated the HMF content of nine Malaysian honey samples, as well as the correlation of HMF formation with physicochemical properties of honey. Based on the recommendation by the International Honey Commission, three methods for the determination of HMF were used: (1) high performance liquid chromatography (HPLC), (2) White spectrophotometry and (3) Winkler spectrophotometry methods. HPLC and White spectrophotometric results yielded almost similar values, whereas the Winkler method showed higher readings. The physicochemical properties of honey (pH, free acids, lactones and total acids) showed significant correlation with HMF content and may provide parameters that could be used to make quick assessments of honey quality. The HMF content of fresh Malaysian honey samples stored for 3-6 months (at 2.80-24.87 mg/kg) was within the internationally recommended value (80 mg/kg for tropical honeys), while honey samples stored for longer periods (12-24 months) contained much higher HMF concentrations (128.19-1131.76 mg/kg). Therefore, it is recommended that honey should generally be consumed within one year, regardless of the type.


Assuntos
Furaldeído/análogos & derivados , Mel/análise , Ácidos/análise , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos/análise , Furaldeído/análise , Concentração de Íons de Hidrogênio , Lactonas/análise , Modelos Lineares , Malásia , Água/análise
20.
Artigo em Inglês | MEDLINE | ID: mdl-21731163

RESUMO

Honey is rich in phenolic compounds, which act as natural antioxidants and are becoming increasingly popular because of their potential role in contributing to human health. A wide range of phenolic constituents is present in honey like quercetin, caffeic acid phenethyl ester (CAPE), acacetin, kaempferol, galangin which have promising effect in the treatment of cardiovascular diseases. Many epidemiological studies have shown that regular intake of phenolic compounds is associated with reduced risk of heart diseases. In coronary heart disease, the protective effects of phenolic compounds include mainly antithrombotic, anti-ischemic, anti-oxidant, and vasorelaxant. It is suggested that flavonoids decrease the risk of coronary heart disease by three major actions: improving coronary vasodilatation, decreasing the ability of platelets in the blood to clot, and preventing low-density lipoproteins (LDLs) from oxidizing. In this review paper, we discussed the preventive role of polyphenols of honey against cardiovascular diseases.


Assuntos
Antioxidantes/farmacologia , Flavonoides/química , Cardiopatias/prevenção & controle , Mel/análise , Fenóis/química , Antioxidantes/uso terapêutico , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Polifenóis
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