Displaying publications 901 - 920 of 1883 in total

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  1. Armas Rojas NB, Lacey B, Soni M, Charles S, Carter J, Varona-Pérez P, et al.
    BMC Public Health, 2021 05 27;21(1):963.
    PMID: 34039286 DOI: 10.1186/s12889-021-10911-9
    BACKGROUND: Cardiovascular disease accounts for about one-third of all premature deaths (ie, age =120 mmHg), diabetes, and BMI (>=22.5 kg/m2): 20 mmHg higher usual SBP about doubled cardiovascular mortality (RR 2.02, 95%CI 1.88-2.18]), as did diabetes (2.15, 1.95-2.37), and 10 kg/m2 higher usual BMI (1.92, 1.64-2.25). RR were similar in men and in women. The association with BMI and cardiovascular mortality was almost completely attenuated following adjustment for the mediating effect of SBP. Elevated SBP (>=120 mmHg), diabetes and raised BMI (>=22.5 kg/m2) accounted for 27%, 14%, and 16% of cardiovascular deaths, respectively.

    CONCLUSIONS: This large prospective study provides direct evidence for the effects of these major risk factors on cardiovascular mortality in Cuba. Despite comparatively low levels of these risk factors by international standards, the strength of their association with cardiovascular death means they nevertheless exert a substantial impact on premature mortality in Cuba.

    Matched MeSH terms: Blood Pressure
  2. Yuen KH, Desmukh AA, Newton JM
    Pharm Res, 1993 Apr;10(4):588-92.
    PMID: 8483843
    A novel multiparticulate sustained-release theophylline formulation, which consisted of spherical drug pellets coated with a rate-controlling membrane, was evaluated in vivo. Two preparations that differ solely in the coat thickness, and hence rate of in vitro drug release, were studied in comparison with a solution of the drug. Both preparations produced serum concentration profiles that are reflective of a slow and sustained rate of absorption. The in vivo release versus time profiles calculated using a deconvolution procedure showed that the two preparations differed in the rate but not the extent of drug release. Satisfactory correlation was also obtained between the in vivo and the in vitro results. When the two preparations were further compared using the parameters, time to reach peak concentration (Tp), peak concentration (Cp), and total area under the serum concentration versus time curves (AUC), a statistically significant difference was observed in the Tp and Cp values but not the AUC values, suggesting that the preparations differed in the rate but not the extent of absorption. In addition, the extent of absorption from both preparations was comparable to that obtained with the drug solution.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  3. Chan KL, Choo CY, Morita H, Itokawa H
    Planta Med, 1998 Dec;64(8):741-5.
    PMID: 17253320 DOI: 10.1055/s-2006-957570
    An analytical method using HPLC with UV detection was developed to investigate the quassinoid content of Eurycoma longifolia Jack (Simaroubaceae) collected from various sources. Eurycomanone (1), longilactone (2), 14,15beta-dihydroxyklaineanone (3), 15beta-acetyl-14-hydroxyklaineanone (4), 6alpha-hydroxyeurycomalactone (5), and eurycomalactone (7) were isolated as reference standards and together with the synthesized 1beta,12alpha,15beta-triacetyleurycomanone (6, internal standard), were identified by NMR, MS, UV and IR spectroscopies. Their coefficient of variation values for 0.50-35 microg ml(-1) concentrations of quassinoids and their retention times measured within- and between-day were small. The recoveries of the spiked quassinoids in E. longifolia samples and their detection limits at 8.5 times signal to noise ratio were 99.75-109.13% and 0.01 microg ml(-1), respectively. From the root samples analysed, 1 had the highest concentration, being about 16.8-39.6 fold higher than the other quassinoids 2, 3, 5, 7 but 145.3 fold higher than 4 which showed the lowest concentration.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  4. Yuen KH, Peh KK, Billa N, Chan KL, Toh WT
    Drug Dev Ind Pharm, 1998 Feb;24(2):193-6.
    PMID: 15605452
    The bioavailability of a generic preparation of acyclovir (Avorax) was compared with the innovator product, Zovirax. Twelve healthy volunteers participated in the study, conducted according to a randomized, two-way crossover design. The preparations were compared using the parameters area under the plasma concentration time curve (AUC(0-infinity), peak plasma concentration (Cmax), and time to reach peak plasma concentration (Tmax). No statistically significant difference was observed between the Tmax or the logarithmic transformed AUC(0-infinity) and C(max) values of the two preparations. In addition, the 90% confidence interval for the ratio of the logarithmic transformed AUC(0-infinity) values of Avorax over those of Zovirax was found to lie between 0.85 and 1.06, while that of the logarithmic transformed Cmax values was between 0.95 and 1.25, being within the bioequivalence limit of 0.80-1.25. Moreover, the elimination rate constant (k(e)), elimination half-life (t(1/2)), and apparent volume of distribution (Vd) values obtained with the two preparations were comparable and not significantly different statistically.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  5. Peh KK, Wong CF, Yuen KH
    Drug Dev Ind Pharm, 2000 Apr;26(4):447-50.
    PMID: 10769787
    Lipophilicity was evaluated as a possible mechanism for drug retardation from a glyceryl monostearate matrix system. Lipophilicity of the glyceryl monostearate matrix system was studied using contact angle measurement of water droplets on the surface of compressed disks, extrudate ascension of water, and movement of water through a powder mixture packed in a high-performance liquid chromatographic (HPLC) column. Increase in glyceryl monostearate content resulted in an increase in water droplet contact angle, decrease in the rate of water ascending the extrudate, and increase in the pressure values as a function of flow rate of water moving through the powder mixture. These could be due to the increase in lipophilicity of the matrix, rendering the matrix less wettable. As a result, the rate of water penetration into the matrix decreased, and the drug release could be sustained.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  6. Parn KW, Ling WC, Chin JH, Lee SK
    Nutrients, 2022 Nov 01;14(21).
    PMID: 36364864 DOI: 10.3390/nu14214605
    This study aimed to identify the no-observed-adverse-effect level (NOAEL) of dietary epigallocatechin gallate (EGCG) supplementation and its possible antihypertensive and nutrigenomics effects in modulating intrarenal renin-angiotensin system (RAS) gene expression in spontaneously hypertensive rats (SHR). EGCG (50, 250, 500 or 1000 mg/kg b.w. i.g., once daily) was administered to SHR for 28 days. All the SHR survived with no signs of systemic toxicity. Increased alanine aminotransferase (ALT), aspartate aminotransferase (AST) and thiobarbituric acid reactive substances (TBARS) were evident in SHR supplemented with 500 and 1000 mg/kg b.w. but not in those supplemented with lower doses of EGCG. Subsequently, the NOAEL of EGCG was established at 250 mg/kg b.w., and the same protocol was replicated to assess its effects on blood pressure and renal RAS-related genes in SHR. The systolic blood pressure (SBP) of the EGCG group was consistently lower than the control group. The mRNA levels of cortical Agtr2 and Ace2 and medullary Agtr2, Ace and Mas1 were upregulated while medullary Ren was downregulated in EGCG group. Statistical analysis showed that SBP reduction was associated with the changes in medullary Agtr2, Ace, and Ren. Dietary EGCG supplementation exhibits antihypertensive and nutrigenomics effects through activation of intrarenal Ace and Agtr2 and suppression of Ren mediators, while a high dose of EGCG induced liver damage in SHR. In future clinical studies, liver damage biomarkers should be closely monitored to further establish the safety of the long-term use of EGCG.
    Matched MeSH terms: Blood Pressure
  7. Li Y, Li S, Wang Y, Zhou J, Yang J, Ma J
    J Fr Ophtalmol, 2021 Dec;44(10):1596-1604.
    PMID: 34454773 DOI: 10.1016/j.jfo.2021.05.005
    BACKGROUND: The main risks for glaucoma are increased intraocular pressure (IOP) and decreased ocular perfusion pressure (OPP). This review aims to examine the potential impact of lower limb isometric resistance exercise on intraocular pressure and ocular perfusion pressure.

    METHOD: A meta-analysis was conducted to determine the potential impact of isometric exercise on IOP and OPP. The literature on the relationship between isometric resistance exercise and IOP was systematically searched according to the "Cochrane Handbook" in the databases of Pubmed, Web of Science, EBSCO, and Scopus through December 31, 2020. The search terms used were "exercise," "train," "isometric," "intraocular pressure," and "ocular perfusion pressure," and the mean differences of the data were analyzed using the Stata 16.0 software, with a 95% confidence interval.

    RESULTS: A total of 13 studies, which included 268 adult participants consisting of 162 men and 106 women, were selected. All the exercise programs that were included were isometric resistance exercises of the lower limbs with intervention times of 1min, 2min, or 6min. The increase in IOP after intervention was as follows: I2=87.1%, P=0.001 using random-effects model combined statistics, SMD=1.03 (0.48, 1.59), and the increase in OPP was as follows: I2=94.5%, P=0.001 using random-effects model combined statistics, SMD=2.94 (1.65, 4.22), with both results showing high heterogeneity.

    CONCLUSION: As isometric exercise may cause an increase in IOP and OPP, therefore, people with glaucoma and related high risk should perform isometric exercise with caution.

    Matched MeSH terms: Intraocular Pressure
  8. Kamal MSA, Mediani A, Kasim N, Ismail NH, Satar NA, Azis NA, et al.
    J Pharm Biomed Anal, 2022 Feb 20;210:114579.
    PMID: 35016031 DOI: 10.1016/j.jpba.2021.114579
    Ficus deltoidea var angustifolia (FD-A) reduces blood pressure in spontaneously hypertensive rats (SHR) but the mechanism remains unknown. Changes in urine metabolites following FD-A treatment in SHR were, therefore, examined to identify the mechanism of its antihypertensive action. Male SHR were given either FD-A (1000 mg kg-1 day-1) or losartan (10 mg kg-1 day-1) or 0.5 mL of ethanolic-water (control) daily for 4 weeks. Systolic blood pressure (SBP) was measured every week and urine spectra data acquisition, on urine collected after four weeks of treatment, were compared using multivariate data analysis. SBP in FD-A and losartan treated rats was significantly lower than that in the controls after four weeks of treatment. Urine spectra analysis revealed 24 potential biomarkers with variable importance projections (VIP) above 0.5. These included creatine, hippurate, benzoate, trimethylamine N-oxide, taurine, dimethylamine, homocysteine, allantoin, methylamine, n-phenylacetylglycine, guanidinoacetate, creatinine, lactate, glucarate, kynurenine, ethanolamine, betaine, 3-hydroxybutyrate, glycine, lysine, glutamine, 2-hydroxyphenylacetate, 3-indoxylsulfate and sarcosine. From the profile of these metabolites, it seems that FD-A affects urinary levels of metabolites like taurine, hypotaurine, glycine, serine, threonine, alanine, aspartate and glutamine. Alterations in these and the pathways involved in their metabolism might underlie the molecular mechanism of its antihypertensive action.
    Matched MeSH terms: Blood Pressure
  9. Azri FA, Selamat J, Sukor R
    Sensors (Basel), 2017 Nov 30;17(12).
    PMID: 29189760 DOI: 10.3390/s17122776
    Palm kernel cake (PKC) is the solid residue following oil extraction of palm kernels and useful to fatten animals either as a single feed with only minerals and vitamins supplementation, or mixed with other feedstuffs such as corn kernels or soy beans. The occurrence of mycotoxins (aflatoxins, ochratoxins, zearalenone, and fumonisins) in feed samples affects the animal's health and also serves as a secondary contamination to humans via consumption of eggs, milk and meats. Of these, aflatoxin B₁ (AFB₁) is the most toxically potent and a confirmed carcinogen to both humans and animals. Methods such as High Performance Liquid Chromatography (HPLC) and Liquid Chromatography-Mass Spectrometry (LC-MS/MS) are common in the determination of mycotoxins. However, these methods usually require sample pre-treatment, extensive cleanup and skilled operator. Therefore, in the present work, a rapid method of electrochemical immunosensor for the detection of AFB₁ was developed based on an indirect competitive enzyme-linked immunosorbent assay (ELISA). Multi-walled carbon nanotubes (MWCNT) and chitosan (CS) were used as the electrode modifier for signal enhancement.N-ethyl-N'-(3-dimethylaminopropyl)-carbodiimide (EDC) andN-hydroxysuccinimide (NHS) activated the carboxyl groups at the surface of nanocomposite for the attachment of AFB₁-BSA antigen by covalent bonding. An indirect competitive reaction occurred between AFB₁-BSA and free AFB₁ for the binding site of a fixed amount of anti-AFB₁ antibody. A catalytic signal based on horseradish peroxidase (HRP) in the presence of hydrogen peroxide (H₂O₂) and 3,3',5,5'-tetramethylbenzidine (TMB) mediator was observed as a result of attachment of the secondary antibody to the immunoassay system. As a result, the reduction peak of TMB(Ox)was measured by using differential pulse voltammetry (DPV) analysis. Based on the results, the electrochemical surface area was increased from 0.396 cm² to 1.298 cm² due to the electrode modification with MWCNT/CS. At the optimal conditions, the working range of the electrochemical immunosensor was from 0.0001 to 10 ng/mL with limit of detection of 0.1 pg/mL. Good recoveries were obtained for the detection of spiked feed samples (PKC, corn kernels, soy beans). The developed method could be used for the screening of AFB₁ in real samples.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  10. Ting Yl J, Faisal HA, Pan SW
    Int Ophthalmol, 2019 Jan;39(1):203-206.
    PMID: 29197945 DOI: 10.1007/s10792-017-0774-1
    PURPOSE: To describe a rare case of spontaneous expulsive suprachoroidal haemorrhage (SESCH) in an asymptomatic elderly patient.

    METHOD: This is a case report of a 76-year-old Chinese female, presented as an emergency with spontaneous left eye bleeding. She had underlying uncontrolled hypertension, no other systemic illness and not on anticoagulant. She has a history of right eye cataract operation, right eye angle-closure glaucoma and left eye absolute glaucoma complicated with painless left blind eye. Ocular examination over left eye showed no light perception and demonstrated presence of fresh bleed, expulsion of lens and prolapsed uveal contents, while right eye examination was unremarkable. Patient subsequently underwent evisceration and was uneventful.

    RESULTS: Routine blood investigations including coagulation profile came back as normal. Surgical findings include perforated cornea more than three-fourths with prolapsed uveal contents and fragile conjunctiva. No other significant macroscopic conditions were noted. Histology and culture came back with growth of Pseudomonas aeuroginosa with no evidence of malignancy.

    DISCUSSION: SESCH is a rare but serious sight-threatening ocular condition associated with multiple risk factors including arteriosclerosis, vascular disease, glaucoma, diabetes, intraocular malignancy and diseased eye wall. The predisposing factors involved in this case include advanced age, glaucoma with persistent high intraocular pressure, uncontrolled hypertension and presence of infection.

    Matched MeSH terms: Intraocular Pressure
  11. Azir M, Abbasiliasi S, Tengku Ibrahim TA, Manaf YNA, Sazili AQ, Mustafa S
    Foods, 2017 Nov 09;6(11).
    PMID: 29120362 DOI: 10.3390/foods6110098
    The present study investigates the detection of lard in cocoa butter through changes in fatty acids composition, triacylglycerols profile, and thermal characteristics. Cocoa butter was mixed with 1% to 30% (v/v) of lard and analyzed using a gas chromatography flame ionization detector, high performance liquid chromatography, and differential scanning calorimetry. The results revealed that the mixing of lard in cocoa butter showed an increased amount of oleic acid in the cocoa butter while there was a decrease in the amount of palmitic acid and stearic acids. The amount of POS, SOS, and POP also decreased with the addition of lard. A heating thermogram from the DSC analysis showed that as the concentration of lard increased from 3% to 30%, two minor peaks at -26 °C and 34.5 °C started to appear and a minor peak at 34.5 °C gradually overlapped with the neighbouring major peak. A cooling thermogram of the above adulterated cocoa butter showed a minor peak shift to a lower temperature of -36 °C to -41.5 °C. Values from this study could be used as a basis for the identification of lard from other fats in the food authentication process.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  12. Stephen ID, Hiew V, Coetzee V, Tiddeman BP, Perrett DI
    Front Psychol, 2017;8:1883.
    PMID: 29163270 DOI: 10.3389/fpsyg.2017.01883
    Facial cues contribute to attractiveness, including shape cues such as symmetry, averageness, and sexual dimorphism. These cues may represent cues to objective aspects of physiological health, thereby conferring an evolutionary advantage to individuals who find them attractive. The link between facial cues and aspects of physiological health is therefore central to evolutionary explanations of attractiveness. Previously, studies linking facial cues to aspects of physiological health have been infrequent, have had mixed results, and have tended to focus on individual facial cues in isolation. Geometric morphometric methodology (GMM) allows a bottom-up approach to identifying shape correlates of aspects of physiological health. Here, we apply GMM to facial shape data, producing models that successfully predict aspects of physiological health in 272 Asian, African, and Caucasian faces - percentage body fat (21.0% of variance explained), body mass index (BMI; 31.9%) and blood pressure (BP; 21.3%). Models successfully predict percentage body fat and blood pressure even when controlling for BMI, suggesting that they are not simply measuring body size. Predicted values of BMI and BP, but not percentage body fat, correlate with health ratings. When asked to manipulate the shape of faces along the physiological health variable axes (as determined by the models), participants reduced predicted BMI, body fat and (marginally) BP, suggesting that facial shape provides a valid cue to aspects of physiological health.
    Matched MeSH terms: Blood Pressure
  13. Hariri F, Abdul Rahman ZA, Bahuri NFA, Azmi MN, Abdullah NA, Ganesan D
    J Oral Maxillofac Surg, 2018 03;76(3):646.e1-646.e12.
    PMID: 29268076 DOI: 10.1016/j.joms.2017.11.029
    Crouzon syndrome (CS) is the most common craniosynostosis syndrome and requires a comprehensive management strategy for the optimization of care and functional rehabilitation. This report presents a case series of 6 pediatric patients diagnosed with CS who were treated with distraction osteogenesis (DO) to treat serious functional issues involving severe orbital proptosis, an obstructed nasopharyngeal airway, and increased intracranial pressure (ICP). Three boy and 3 girls were 8 months to 6 years old at the time of the operation. The mean skeletal advancement was 16.1 mm (range, 10 to 27 mm) with a mean follow-up of 31.7 months (range, 13 to 48 months). Reasonable and successful outcomes were achieved in most patients as evidenced by adequate eye protection, absence of signs and symptoms of increased ICP, and tracheostomy tube decannulation except in 1 patient. Complications were difficult fixation of external stabilizing pins in the distraction device (n = 1) and related to surgery (n = 4). Although DO can be considered very technical and can have potentially serious complications, the technique produces favorable functional and clinical outcomes in treating severe CS.
    Matched MeSH terms: Intracranial Pressure
  14. Zakaria ZA, Mahmood ND, Mamat SS, Nasir N, Omar MH
    Front Pharmacol, 2017;8:982.
    PMID: 29497375 DOI: 10.3389/fphar.2017.00982
    Methanol extract ofMuntingia calaburaL. (family Muntingiaceae) leaf has been reported to exert various pharmacological activities including hepatoprotection. The present study was carried out to identify the most effective hepatoprotective partition derived from the extract and to determine the mechanisms of action involved. The extract was partitioned using solvents with different polarity to yield petroleum ether (PEMC), ethyl acetate (EAMC), and aqueous (AQMC) extracts. Each extract, at 250 mg/kg, was subjected to the paracetamol (PCM)-induced hepatotoxic assay and several parameters such as liver weight, liver/body weight ratio, serum liver enzymes' level, and histopathological examinations were determined. Each partition was also tested for their antioxidant and anti-inflammatory potentials. The most effective extract (AQMC) was prepared in additional dose of 50 and 500 mg/kg, and then subjected to the same liver toxicity test in addition to the endogenous antioxidant enzymes assay. Moreover, AQMC was also subjected to the phytochemical screening and HPLC analysis. Overall, from the results obtained: AQMC exerted significant (p< 0.05): (i) antioxidant activity when assessed using the DPPH, SOD and ORAC assays with high TPC detected; (ii) anti-inflammatory activity via LOX, but not XO pathway; (iii) hepatoprotective activity indicated by its ability to reverse the effect of PCM on the liver weight and liver/body weight ratio, the level of serum liver enzymes (ALT, AST, and ALP), and activity of several endogenous antioxidant enzymes (SOD and CAT). Phytochemicals analyses demonstrated the presence of several flavonoid-based bioactive compounds such as gallic acid and quercetin, which were reported to possess hepatoprotective activity. In conclusion, AQMC exerts hepatoprotective activity against the PCM-induced toxicity possibly by having a remarkable antioxidant potential and ability to activate the endogenous antioxidant system possibly via the synergistic action of its phytoconstituents.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  15. Cheong, C.K., Hajeb, P., Jinap, S., Ismail-Fitry, M.R.
    MyJurnal
    Sulfonamides (SAs), synthetic antibiotics, are commonly used by veterinarians in chicken for therapeutic, prophylactic or as growth promoter and halt the growth of bacteria in animal production. Four common SAs, Sulfadiazine (SDZ), Sulfamethazine (SMZ), Sulfamethoxazole (SMX) and Sulfaquinoxaline (SQX), were determined in chicken breast and liver samples using reverse phase HPLC using UV detector at 266nm. The concentration of SAs detected in samples from 11 states in Peninsular Malaysia ranged from 0.006-0.062 µg/g in breast meat samples and 0.08-0.193 µg/g in liver samples. Except for sample from Johor, concentration of SAs in all the samples were lower than MRLs established by Malaysia (0.1 µg/g). Exposure of sulfonamides in Malaysian consumers ranged from 0.002-0.088 µg/kg body wt. /day. The highest value of sulfonamides exposure was found in Johor with an estimated daily intake (EDA) of Sulfamethoxazole (SMX) in Johor.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  16. Anahita, A., Asmah, R., Fauziah, O.
    MyJurnal
    This study aimed to determine total phenolic content (TPC), total antioxidant activity (TAA), antioxidant vitamin composition (A, C, and E) of pomegranate fruit. In addition, two edible parts of pomegranate juice, pomegranate seed, and combination of them were compared based on antioxidant properties. TPC was determined by using Folin-Ciocalteu (FC) method based on colorimetric reduction. Ferric reduction ability power (FRAP assay) was used to test the antioxidant activity. Vitamin assessments were conducted by using high performance liquid chromatography (HPLC). Results for antioxidant vitamin composition in pomegranate juice (PJ) showed that the concentration of vitamin A was 22.8 ± 0.69 μg/100 g, vitamin C was 57.8 ± 0.59 mg/100 g, and vitamin E was 0.07 ± 0.01 mg/100 g. Besides, TPC in PJ, pomegranate seed (PS), and pomegranate seed-juice (PSJ) was 2502 ± 54, 165 ± 49, and 2696 ± 49 mg GAE/L, and TAA was 32 ± 5.1, 20 ± 2.8, and 47 ± 5.5 mmol/L respectively. This study revealed that PSJ contained high level of phenolic compounds, antioxidant activity, and vitamin C. In addition, TPC was as main contributor to antioxidant activities, and positively correlated with TAA (r2 = 0.91, p
    Matched MeSH terms: Chromatography, High Pressure Liquid
  17. Hafshejani MK, Ogugbue CJ, Morad N
    3 Biotech, 2014 Dec;4(6):605-619.
    PMID: 28324306 DOI: 10.1007/s13205-013-0192-7
    The decolorization and degradation of Direct Blue 71 were investigated using a mono culture of Pseudomonas aeruginosa. The bacterium was able to decolorize the dye medium to 70.43 % within 48 h under microaerophilic conditions. The medium was then aerated for 24 h to promote the biodegradation of the aromatic amines generated from azo bond cleavage. Reduction in total organic carbon in dye medium was 42.58 % in the microaerophilic stage and 78.39 % in the aerobic stage. The degradation metabolites formed were studied using UV-vis techniques, high performance liquid chromatography, Fourier transform infra red spectroscopy and nuclear magnetic resonance spectroscopy analysis. Data obtained provide evidence for the formation of aromatic amines and their subsequent oxidative biodegradation by a single strain of P. aeruginosa during successive microaerophilic/aerobic stages in the same flask. The influence of incubation temperature (20-45 °C), medium pH (5-10) and initial dye concentration (25-150 mg/L) on decolorization was evaluated to greatly influence decolorization extent. The optimal decolorization conditions were determined by response surface methodology based on three-variable central composite design to obtain maximum decolorization and to determine the significance and interaction effect of the variables on decolorization. The optimal conditions of response were found to be 35.15 °C, pH 8.01 and 49.95 mg/L dye concentration giving an experimental decolorization value of 84.80 %. Very high regression coefficient between the variables and the response (R(2) = 0.9624) indicated a good evaluation of experimental data by polynomial regression model.
    Matched MeSH terms: Chromatography, High Pressure Liquid
  18. Duncan MT, Husain R, Chen HM, Horvath SM
    Am J Hum Biol, 1995;7(3):329-337.
    PMID: 28557027 DOI: 10.1002/ajhb.1310070309
    The interaction of race and climatic adaptation on patterns of cardiovascular reactivity among young adult males was examined. Malay and Chinese subjects living in a tropical climate in the Orient and Caucasians living in a sub-tropical climate in North America were investigated. The cold pressor test with hand immersion in cold water was used as the stressor. Systolic and diastolic blood pressures, cardiac frequency, cardiac output, and stroke volume were measured. The results provided limited evidence for absence of differences in cardiac reactivity among racial groups and for greater vascular reactivity in the Caucasians. Cold immersion also elicited differential responses which could be partially attributed to differences in acclimatizations status. © 1995 Wiley-Liss, Inc.
    Matched MeSH terms: Blood Pressure
  19. Sulaiman A, Farid M, Silva FV
    Food Sci Technol Int, 2017 Jun;23(4):293-309.
    PMID: 28595485 DOI: 10.1177/1082013216685485
    Strawberry puree was processed for 15 min using thermal (65 ℃), high-pressure processing (600 MPa, 48 ℃), and ultrasound (24 kHz, 1.3 W/g, 33 ℃). These conditions were selected based on similar polyphenoloxidase inactivation (11%-18%). The specific energies required for the above-mentioned thermal, high-pressure processing, and power ultrasound processes were 240, 291, and 1233 kJ/kg, respectively. Then, the processed strawberry was stored at 3 ℃ and room temperature for 30 days. The constant pH (3.38±0.03) and soluble solids content (9.03 ± 0.25°Brix) during storage indicated a microbiological stability. Polyphenoloxidase did not reactivate during storage. The high-pressure processing and ultrasound treatments retained the antioxidant activity (70%-74%) better than the thermal process (60%), and high-pressure processing was the best treatment after 30 days of ambient storage to preserve antioxidant activity. Puree treated with ultrasound presented more color retention after processing and after ambient storage than the other preservation methods. For the three treatments, the changes of antioxidant activity and total color difference during storage were described by the fractional conversion model with rate constants k ranging between 0.03-0.09 and 0.06-0.22 day - 1, respectively. In resume, high-pressure processing and thermal processes required much less energy than ultrasound for the same polyphenoloxidase inactivation in strawberry. While high-pressure processing retained better the antioxidant activity of the strawberry puree during storage, the ultrasound treatment was better in terms of color retention.
    Matched MeSH terms: Pressure
  20. Shuib NS, Makahleh A, Salhimi SM, Saad B
    J Chromatogr A, 2017 Aug 11;1510:51-56.
    PMID: 28668367 DOI: 10.1016/j.chroma.2017.06.054
    The determination of aflatoxin M1 in milk using high performance liquid chromatography with photochemical post-column derivatization and fluorescence detection is described. The samples were first extracted and clean-up using the immunoaffinity AFLATEST column originally targeted for aflatoxins B1, B2, G1 and G2. The separation of aflatoxin M1 were performed using C18 Hypersil gold (150mm×4.6mm, 5μm) column at 40°C under isocratic elution. Fluorescence detector (FLD) was set at 360nm and 440nm as excitation and emission, respectively. The use of methanol to replace acetonitrile as the mobile phase resulted in ∼67% peak area enhancement of AFM1. The limit of detection (LOD) and quantification (LOQ) of the analytical method after post-column derivatization without evaporation/reconstitution with mobile phase was 0.0085μgL(-1) and 0.025μgL(-1) respectively. However, LOD and LOQ improved to 0.002 and 0.004μgL(-1) respectively with the addition of evaporation/reconstitution step. The method was statistically validated, showing linear response (R(2)>0.999), good recoveries (85.2-107.0%) and relative standard deviations (RSD) were found to be ≤7%. The proposed method was applied to determine AFM1 contamination in various types of milk and milk products. Only 2 samples were contaminated with aflatoxin M1 (10% incidence). However, the contamination level is below the Malaysian and European legislation limits.
    Matched MeSH terms: Chromatography, High Pressure Liquid
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