Displaying publications 1081 - 1100 of 1919 in total

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  1. Sukor N, Saidin R, Kamaruddin NA
    South. Med. J., 2007 Jan;100(1):73-4.
    PMID: 17269532
    Pheochromocytomas are rare neuroendocrine tumors that produce, metabolize, and usually secrete catecholamines. Although hypertension is a common presenting feature of pheochromocytoma, the tumors occur (or are present) in only 0.1% of patients with hypertension. The variability of symptoms and rarity of occurrence render these tumors difficult to diagnose; many are discovered incidentally during radiological examination or at autopsy. A patient is presented with a pheochromocytoma that was discovered incidentally when she presented with abdominal pain and a normal blood pressure.
    Matched MeSH terms: Blood Pressure/physiology*
  2. Singh HJ, Keah LS, Kumar A, Sirajudeen KN
    Exp. Toxicol. Pathol., 2012 Nov;64(7-8):751-2.
    PMID: 21354772 DOI: 10.1016/j.etp.2011.01.011
    This report documents an incidental finding during a study investigating the effects of melatonin supplementation on the development of blood pressure in SHR. Administration of 10 mg/kg/day of melatonin in drinking water during pregnancy to Wistar-Kyoto (WKY) dams caused a loss of more than 50% of the pups by the age of three weeks and 95% by the age of 6 weeks. There was no maternal morbidity or mortality in the two strains or death of any of the SHR pups. No obvious physical defects were present but mean body weight was lower in the surviving WKY rats when compared to that of melatonin supplemented SHR or non-supplemented WKY pups. The reason for the high mortality in WKY pups is uncertain and appears to be strain if not batch specific. There is a need for caution in its use, particularly during pregnancy, and clearly necessitates more detailed studies.
    Matched MeSH terms: Blood Pressure/drug effects
  3. Hoe SZ, Lee CN, Mok SL, Kamaruddin MY, Lam SK
    Clinics (Sao Paulo), 2011;66(1):143-50.
    PMID: 21437451
    INTRODUCTION: Gynura procumbens has been shown to decrease blood pressure via inhibition of the angiotensinconverting enzyme. However, other mechanisms that may contribute to the hypotensive effect have not been studied.

    OBJECTIVES: To investigate the cardiovascular effects of a butanolic fraction of Gynura procumbens in rats.

    METHODS: Anaesthetized rats were given intravenous bolus injections of butanolic fraction at doses of 2.5-20 mg/kg in vivo. The effect of butanolic fraction on vascular reactivity was recorded in isolated rat aortic rings in vitro.

    RESULTS: Intravenous administrations of butanolic fraction elicited significant (p < 0.001) and dose-dependent decreases in the mean arterial pressure. However, a significant (p < 0.05) decrease in the heart rate was observed only at the higher doses (10 and 20 mg/kg). In isolated preparations of rat aortic rings, phenylephrine (1 × 10⁻⁶ M)- or potassium chloride (8 × 10⁻² M)-precontracted endothelium-intact and -denuded tissue; butanolic fraction (1 × 10⁻⁶ - 1 × 10⁻¹ g/ml) induced similar concentration-dependent relaxation of the vessels. In the presence of 2.5 × 10⁻³ and 5.0 × 10⁻³ g/ml butanolic fraction, the contractions induced by phenylephrine (1 × 10⁻⁹-3 × 10⁻⁵ M) and potassium chloride (1 × 10⁻² - 8 × 10⁻² M) were significantly antagonized. The calcium-induced vasocontractions (1 × 10⁻⁴-1 × 10⁻²M) were antagonized by butanolic fraction concentration-dependently in calcium-free and high potassium (6×10⁻² M) medium, as well as in calcium- and potassium-free medium containing 1×10⁻⁶ M phenylephrine. However, the contractions induced by noradrenaline (1 × 10⁻⁶ M) and caffeine (4.5 × 10⁻² M) were not affected by butanolic fraction.

    CONCLUSION: Butanolic fraction contains putative hypotensive compounds that appear to inhibit calcium influx via receptor-operated and/or voltage-dependent calcium channels to cause vasodilation and a consequent fall in blood pressure.

    Matched MeSH terms: Blood Pressure/drug effects*
  4. Goh PK, Chiu CL, Wang CY, Chan YK, Loo PL
    Anaesth Intensive Care, 2005 Apr;33(2):223-8.
    PMID: 15960405
    The aim of this prospective, double-blind, randomized, placebo-controlled clinical trial was to investigate whether the administration of ketamine before induction with propofol improves its associated haemodynamic profile and laryngeal mask airway (LMA) insertion conditions. Ninety adult patients were randomly allocated to receive either ketamine 0.5 mg x kg(-1) (n = 30), fentanyl 1 microg x kg(-1) (n = 30) or normal saline (n = 30), before induction of anaesthesia with propofol 2.5 mg x kg(-1). Insertion of the LMA was performed 60s after injection of propofol. Arterial blood pressure and heart rate were measured before induction (baseline), immediately after induction, immediately before LMA insertion, immediately after LMA insertion and every minute for three minutes after LMA insertion. Following LMA insertion, the following six subjective endpoints were graded by a blinded anaesthestist using ordinal scales graded 1 to 3: mouth opening, gagging, swallowing, movement, laryngospasm and ease of insertion. Systolic blood pressure was significantly higher following ketamine than either fentanyl (P = 0.010) or saline (P = 0.0001). The median (interquartile range) summed score describing the overall insertion conditions were similar in the ketamine [median 7.0, interquartile range (6.0-8.0)] and fentanyl groups [median 7.0, interquartile range (6.0-8.0)]. Both appeared significantly better than the saline group [median 8.0, interquartile range (6.75-9.25); P = 0.024]. The incidence of prolonged apnoea (> 120s) was higher in the fentanyl group [23.1% (7/30)] compared with the ketamine [6.3% (2/30)] and saline groups [3.3% (1/30)]. We conclude that the addition of ketamine 0.5 mg x kg(-1) improves haemodynamics when compared to fentanyl 1 microg x kg(-1), with less prolonged apnoea, and is associated with better LMA insertion conditions than placebo (saline).
    Matched MeSH terms: Blood Pressure/drug effects*
  5. Parthasarathy S, Ramanathan S, Ismail S, Adenan MI, Mansor SM, Murugaiyah V
    Anal Bioanal Chem, 2010 Jul;397(5):2023-30.
    PMID: 20454783 DOI: 10.1007/s00216-010-3707-7
    A new solid phase extraction method for rapid high performance liquid chromatography-UV determination of mitragynine in plasma has been developed. Optimal separation was achieved with an isocratic mobile phase consisting of acetonitrile-ammonium acetate buffer, 50 mM at pH 5.0 (50:50, v/v). The method had limits of detection and quantification of 0.025 and 0.050 microg/mL, respectively. The method was accurate and precise for the quantitative analysis of mitragynine in human and rat plasma with within-day and between-day accuracies between 84.0 and 109.6%, and their precision values were between 1.7 and 16.8%. Additional advantages over known methods are related to the solid phase extraction technique for sample preparation which yields a clean chromatogram, a short total analysis time, requires a smaller amount of plasma samples and has good assay sensitivity for bioanalytical application. The method was successfully applied in pharmacokinetic and stability studies of mitragynine. In the present study, mitragynine was found to be fairly stable during storage and sample preparation. The present study showed for the first time the detailed pharmacokinetic profiles of mitragynine. Following intravenous administration, mitragynine demonstrated a biphasic elimination from plasma. Oral absorption of the drug was slow, prolonged and was incomplete, with a calculated absolute oral bioavailability value of 3.03%. The variations observed in previous pharmacokinetic studies after oral administration of mitragynine could be attributed to its poor bioavailability rather than to the differences in assay method, metabolic saturation or mitragynine dose.
    Matched MeSH terms: Chromatography, High Pressure Liquid/methods*
  6. Khayoon WS, Saad B, Salleh B, Ismail NA, Abdul Manaf NH, Abdul Latiff A
    Anal Chim Acta, 2010 Oct 29;679(1-2):91-7.
    PMID: 20951862 DOI: 10.1016/j.aca.2010.09.008
    The development of a reversed phase high performance liquid chromatography fluorescence method for the determination of the mycotoxins fumonisin B(1) and fumonisin B(2) by using silica-based monolithic column is described. The samples were first extracted using acetonitrile:water (50:50, v/v) and purified by using a C(18) solid phase extraction-based clean-up column. Then, pre-column derivatization for the analyte using ortho-phthaldialdehyde in the presence of 2-mercaptoethanol was carried out. The developed method involved optimization of mobile phase composition using methanol and phosphate buffer, injection volume, temperature and flow rate. The liquid chromatographic separation was performed using a reversed phase Chromolith(®) RP-18e column (100 mm × 4.6 mm) at 30 °C and eluted with a mobile phase of a mixture of methanol and phosphate buffer pH 3.35 (78:22, v/v) at a flow rate of 1.0 mL min(-1). The fumonisins separation was achieved in about 4 min, compared to approximately 20 min by using a C(18) particle-packed column. The fluorescence excitation and emission were at 335 nm and 440 nm, respectively. The limits of detections were 0.01-0.04 μg g(-1) fumonisin B(1) and fumonisin B(2), respectively. Good recoveries were found for spiked samples (0.1, 0.5, 1.5 μg g(-1) fumonisins B(1) and B(2)), ranging from 84.0 to 106.0% for fumonisin B(1) and from 81.0 to 103.0% for fumonisin B(2). Fifty-three samples were analyzed including 39 food and feeds and 14 inoculated corn and rice. Results show that 12.8% of the food and feed samples were contaminated with fumonisin B(1) (range, 0.01-0.51 μg g(-1)) and fumonisin B(2) (0.05 μg g(-1)). The total fumonisins in these samples however, do not exceed the legal limits established by the European Union of 0.8 μg g(-1). Of the 14 inoculated samples, 57.1% contained fumonisin B(1) (0.16-41.0 μg g(-1)) and fumonisin B(2) (range, 0.22-50.0 μg g(-1)). Positive confirmation of selected samples was carried out using liquid chromatography-tandem mass spectrometry, using triple quadrupole analyzer and operated in the multiple reaction monitoring mode.
    Matched MeSH terms: Chromatography, High Pressure Liquid/methods
  7. Venkatesh G, Majid MI, Ramanathan S, Mansor SM, Nair NK, Croft SL, et al.
    Biomed Chromatogr, 2008 May;22(5):535-41.
    PMID: 18205140 DOI: 10.1002/bmc.965
    A simple, sensitive and specific reversed-phase high-performance liquid chromatographic method with UV detection at 251 nm was developed for quantitation of buparvaquone (BPQ) in human and rabbit plasma. The method utilizes 250 microL of plasma and sample preparation involves protein precipitation followed by solid-phase extraction. The method was validated on a C18 column with mobile phase consisting of ammonium acetate buffer (0.02 m, pH 3.0) and acetonitrile in the ratio of 18:82 (v/v) at a flow rate of 1.1 mL/min. The calibration curves were linear (correlation coefficient>or=0.998) in the selected range. The method is specific and sensitive with limit of quantitation of 50 ng/mL for BPQ. The validated method was found to be accurate and precise in the working calibration range. Stability studies were carried out at different storage conditions and BPQ was found to be stable. Partial validation studies were carried out using rabbit plasma and intra- and inter-day precision and accuracy were within 7%. This method is simple, reliable and can be routinely used for preclinical pharmacokinetic studies for BPQ.
    Matched MeSH terms: Chromatography, High Pressure Liquid/methods*
  8. Habil MH, Gondoyoewono H, Chaudhry HR, Samanwongthai U, Hamid AR, Hashmi IT, et al.
    Int J Clin Pharmacol Ther, 2007 Dec;45(12):631-42.
    PMID: 18184531
    OBJECTIVE: The objective of this study was to assess the effectiveness and safety of olanzapine in the treatment of schizophrenia among Asian patients in an outpatient setting.

    METHODS: This was an open-label, prospective, observational study involving 339 patients from Indonesia, Pakistan, Malaysia, Thailand, and Singapore. Brief Psychiatric Rating Scale (BPRS), Clinical Global Impression Severity scale (CGI-S), and safety parameters were assessed.

    RESULTS: 62% of patients responded to olanzapine treatment, defined a priori as a reduction in BPRS of > 40% from baseline. Following the 8-week treatment period, the BPRS total, BPRS positive, BPRS negative, and CGI-S scores decreased by 18.7 (95% CI: 17.4, 20.2), 6.1 (5.6, 6.6), 2.9 (2.6, 3.2), and 1.5 points (median 1.0), respectively (p < 0.0001). In total, 31 of the 339 patients (9.1%) failed to complete the study according to the study description. Loss to follow-up and personal conflict were the most common reasons for discontinuation. There were 30 treatment-emergent adverse events with six serious cases, assessed as unrelated to study drug, reported.

    CONCLUSION: This study further demonstrates the effectiveness and safety of olanzapine in actual clinical practice settings, in reducing the severity of psychopathological symptoms in Asian patients with schizophrenia.

    Matched MeSH terms: Blood Pressure/drug effects
  9. Tajunisah I, Reddy SC, Fathilah J
    Graefes Arch Clin Exp Ophthalmol, 2007 Dec;245(12):1851-7.
    PMID: 17901971
    BACKGROUND: A case-controlled prospective study was conducted to evaluate the diurnal variation of intraocular pressure (IOP); the mean, the amplitude of variation and the peak and trough times of pressure readings in the suspected open-angle glaucoma patients as compared with a control group. We also looked at the outcome of these suspects after diurnal variation of IOP measurements.

    METHODS: Diurnal variation of intraocular pressure was measured in 202 eyes of suspected open-angle glaucoma patients and 100 control eyes, at 4-hourly intervals for 24 hours (phasing). Based on the phasing results, optic disc changes and visual field defects, the patients were diagnosed as primary open angle glaucoma (POAG), normal tension glaucoma (NTG), ocular hypertension (OHT), or physiologic cup (PC), or still remained as glaucoma suspects due to inconclusive diagnosis. The last group (glaucoma suspects) was then followed up 6-monthly for their eventual outcome.

    RESULTS: The highest percentage of suspected glaucoma patients had peak (maximum) readings in the mid-morning (10-11 A.M.) and trough (minimum) readings after midnight (2-3 A.M.); the highest percentage of control group had peak readings in the late evening (6-7 P.M.) and trough readings after midnight (2-3 A.M.). The mean amplitude of variance was 6 mm Hg in suspected glaucoma group and 4 mm Hg in the control group. After 'phasing', 18.8% of the suspected glaucoma patients were diagnosed as POAG, 16.8% as NTG, 5% as OHT, and 28.7% as physiologic cup; 30.9% remained as glaucoma suspects. After 4 years follow-up, 70% of the glaucoma suspects still remained as glaucoma suspects, 6.7% developed NTG and another 6.7% POAG; 16.6% were normal.

    CONCLUSIONS: Serial measurement of IOP ( phasing) in a 24-hour period is still needed, in order not to miss the peak and the trough IOP readings in suspected open-angle glaucoma patients, which helps in better management of glaucoma. Among 30.9% of patients who remained as glaucoma suspects after the initial phasing, 13.4% developed NTG/POAG over a period of 4 years.

    Matched MeSH terms: Intraocular Pressure/physiology*
  10. Liew KB, Loh GO, Tan YT, Peh KK
    Biomed Chromatogr, 2015 Jun;29(6):953-60.
    PMID: 25400284 DOI: 10.1002/bmc.3378
    A simple, rapid, specific and reliable UFLC coupled with ESI-MSMS assay method to simultaneously quantify sildenafil and N-desmethyl sildenafil, with loperamide as internal standard, was developed. Chromatographic separation was performed on a Thermo Scientific Accucore C18 column with an isocratic mobile phase composed of 0.1% v/v formic acid in purified water-methanol (20:80, v/v), at a flow rate of 0.3 mL/min. Sildenafil, N-desmethyl sildenafil and loperamide were detected with proton adducts at m/z 475.4 > 58.2, 461.3 > 85.2 and 477.0 > 266.1 in multiple reaction monitoring positive mode, respectively. Both analytes and internal standard were extracted by diethyl ether. The method was validated over a linear concentration range of 10-800 ng/mL for sildenafil and 10-600 ng/mL for N-desmethyl sildenafil with correlation coefficient (r(2) ) ≥0.9976 for sildenafil and (r(2) ) ≥0.9992 for N-desmethyl sildenafil. The method was precise, accurate and stable. The proposed method was applied to study the bioequivalence between a 100 mg dose of two pharmaceutical products: Viagra (original) and Edyfil (generic) products. AUC0-t , Cmax and Tmax were 2285.79 ng h/mL, 726.10 ng/mL and 0.94 h for Viagra and 2363.25 ng h/mL, 713.91 ng/mL and 0.83 hour for Edyfil. The 90% confidence interval of these parameters of this study fall within the regulatory range of 80-125%, hence they are considered as bioequivalent.
    Matched MeSH terms: Chromatography, High Pressure Liquid/methods*
  11. Su TT, Majid HA, Nahar AM, Azizan NA, Hairi FM, Thangiah N, et al.
    BMC Public Health, 2014;14 Suppl 3:S4.
    PMID: 25436830 DOI: 10.1186/1471-2458-14-S3-S4
    Death rates due to hypertension in low and middle income countries are higher compared to high income countries. The present study is designed to combine life style modification and home blood pressure monitoring for control of hypertension in the context of low and middle income countries.
    Matched MeSH terms: Blood Pressure Monitoring, Ambulatory/psychology*
  12. Hamzaid NA, Tean LT, Davis GM, Suhaimi A, Hasnan N
    Spinal Cord, 2015 May;53(5):375-9.
    PMID: 25366533 DOI: 10.1038/sc.2014.187
    STUDY DESIGN: Prospective study of two cases.

    OBJECTIVES: To describe the effects of electrical stimulation (ES) therapy in the 4-week management of two sub-acute spinal cord-injured (SCI) individuals (C7 American Spinal Injury Association Impairment Scale (AIS) B and T9 AIS (B)).

    SETTING: University Malaya Medical Centre, Kuala Lumpur, Malaysia.

    METHODS: A diagnostic tilt-table test was conducted to confirm the presence of orthostatic hypotension (OH) based on the current clinical definitions. Following initial assessment, subjects underwent 4 weeks of ES therapy 4 times weekly for 1 h per day. Post-tests tilt table challenge, both with and without ES on their rectus abdominis, quadriceps, hamstrings and gastrocnemius muscles, was conducted at the end of the study (week 5). Subjects' blood pressures (BP) and heart rates (HR) were recorded every minute during pre-test and post-tests. Orthostatic symptoms, as well as the maximum tolerance time that the subjects could withstand head up tilt at 60°, were recorded.

    RESULTS: Subject A improved his orthostatic symptoms, but did not recover from clinically defined OH based on the 20-min duration requirement. With concurrent ES therapy, 60° head up tilt BP was 89/62 mm Hg compared with baseline BP of 115/71 mm Hg. Subject B fully recovered from OH demonstrated by BP of 105/71 mm Hg during the 60° head up tilt compared with baseline BP of 124/77 mm Hg. Both patients demonstrated longer tolerance time during head up tilt with concomitant ES (subject A: pre-test 4 min, post-test without ES 6 min, post-test with ES 12 min; subject B: pre-test 4 min, post-test without ES 28 min, post-test with ES 60 min).

    CONCLUSIONS: Weekly ES therapy had positive effect on OH management in sub-acute SCI individuals.

    Matched MeSH terms: Blood Pressure/physiology
  13. Tan HK, Ahmad Tajuddin LS, Lee MY, Ismail S, Wan-Hitam WH
    PMID: 26065503 DOI: 10.1097/APO.0000000000000058
    PURPOSE: To determine the mean central corneal thickness (CCT) and the relationship between the CCT and visual field progression in primary angle closure (PAC) and primary angle closure glaucoma (PACG).

    DESIGN: A combined cross-sectional and prospective study on PAC and PACG.

    METHODS: A total of 35 eyes were included in the study for each group of normal control, PAC, and PACG patients from eye clinics in Kota Bharu, state of Kelantan, Malaysia, from January 2007 to November 2009. The PAC and PACG patients were divided into thin and thick CCT groups. They were followed up for 12 to 18 months for visual field progression assessment with their mean Advanced Glaucoma Intervention Study (AGIS) score.

    RESULTS: The CCT was 516.8 ± 26.0 µm for PAC and 509.7 ± 27.4 µm for PACG. Both were significantly thinner compared with the control group with CCT of 540 ± 27.8 µm (P < 0.001). There was a statistically significant increase in the mean AGIS score after 12.9 ± 1.7 months of follow-up in the thin CCT group for PACG (P = 0.002). However, no significant increase in the mean AGIS score was found for the thick CCT group in PACG and for both thin and thick CCT in PAC.

    CONCLUSIONS: The PAC and PACG had statistically significant thinner CCT compared with the controls. Thin CCT was associated with visual field progression based on the mean AGIS score in PACG.

    Matched MeSH terms: Intraocular Pressure*
  14. Chen J, Ahmad R, Suenaga H, Li W, Swain M, Li Q
    J Biomech, 2015 Feb 5;48(3):512-9.
    PMID: 25560272 DOI: 10.1016/j.jbiomech.2014.11.043
    Although implant-retained overdenture allows edentulous patients to take higher occlusal forces than the conventional complete dentures, the biomechanical influences have not been explored yet. Clinically, there is limited knowledge and means for predicting localized bone remodelling after denture treatment with and without implant support. By using finite element (FE) analysis, this article provides an in-silico approach to exploring the treatment effects on the oral mucosa and potential resorption of residual ridge under three different denture configurations in a patient-specific manner. Based on cone beam computerized tomography (CBCT) scans, a 3D heterogeneous FE model was created; and the supportive tissue, mucosa, was characterized as a hyperelastic material. A measured occlusal load (63N) was applied onto three virtual models, namely complete denture, two and four implant-retained overdentures. Clinically, the bone resorption was measured after one year in the two implant-retained overdenture treatment. Despite the improved stability and enhanced masticatory function, the implant-retained overdentures demonstrated higher hydrostatic stress in mucosa (43.6kPa and 39.9kPa for two and four implants) at the posterior ends of the mandible due to the cantilever effect, than the complete denture (33.4kPa). Hydrostatic pressure in the mucosa signifies a critical indicator and can be correlated with clinically measured bone resorption, pointing to severer mandibular ridge resorption posteriorly with implant-retained overdentures. This study provides a biomechanical basis for denture treatment planning to improve long-term outcomes with minimal residual ridge resorption.
    Matched MeSH terms: Hydrostatic Pressure*
  15. Agarwal R, Krasilnikova AV, Raja IS, Agarwal P, Mohd Ismail N
    Eur J Pharmacol, 2014 May 5;730:8-13.
    PMID: 24583339 DOI: 10.1016/j.ejphar.2014.02.021
    Angiotensin converting enzyme inhibitors (ACEIs) have been shown to lower intraocular pressure (IOP). Since, the ACEIs cause increased tissue prostaglandin levels, we hypothesized that the mechanisms of ACEI-induced IOP reduction have similarity with those of prostaglandin analogs. The present study investigated the involvement of matrix metalloproteinases (MMPs) and cytokine activity modulation as the underlying mechanisms of ACEI-induced ocular hypotension. The IOP lowering effect of single drop of enalaprilat dehydrate 1% was evaluated in rats pretreated with a broad spectrum MMP inhibitor or a cytokine inhibitor. Effect of angiotensin receptor blocker, losartan potassium 2%, was also studied to evaluate involvement of angiotensin II receptor type 1 (AT1) in IOP lowering effect of ACEI. Topical treatment with single drop of enalaprilat resulted in significant IOP reduction in treated eye with mean peak reduction 20.3% at 3h post-instillation. Treatment with losartan resulted in a peak IOP reduction of 13.3%, which was significantly lower than enalaprilat, indicating involvement of mechanisms in addition to AT1 blockade. Pretreatment with a broad spectrum MMP inhibitor or a cytokine inhibitor significantly attenuated the enalprilat-induced IOP reduction with mean peak IOP reduction of 11.2% and 13.6% respectively. The IOP-lowering effect of enalaprilat seems to be attributed to reduced angiotensin II type 1 receptor stimulation and modulation of MMP and cytokines activities.
    Matched MeSH terms: Intraocular Pressure/drug effects*
  16. Lim WY, Kwek K, Chong YS, Lee YS, Yap F, Chan YH, et al.
    J Hypertens, 2014 Apr;32(4):857-64.
    PMID: 24390251 DOI: 10.1097/HJH.0000000000000096
    OBJECTIVE: Greater maternal adiposity is a potentially modifiable risk factor for elevated blood pressure during pregnancy; however, the association has been little studied in Asian populations, and no study has evaluated potential differences in the adiposity-blood pressure relation between ethnic groups or interaction with gestational diabetes.

    METHODS: We performed a cross-sectional evaluation of a Singapore mother-offspring cohort comprising 799 pregnant Chinese, Malay and Indian women. Data on body weight, height, skinfold thickness and glycaemia (oral glucose tolerance test) were collected during the 2nd trimester; peripheral SBP and DBP were measured using an oscillometric device and central pressures by noninvasive radial applanation tonometry. The associations between adiposity measures BMI and sum of skinfold thickness and blood pressure outcomes were examined by linear regression with adjustment for potential confounders.

    RESULTS: Higher maternal BMI was associated with elevated peripheral and central pressures: the increases in pressure (mmHg) for each kg/m(2) increase in BMI were 1.19 (95% confidence interval, 1.03-1.36) for peripheral SBP, 0.76 (0.63-0.89) for peripheral DBP, 1.02 (0.87-1.17) for central systolic pressure and 0.26 (0.16-0.37) for central pulse pressure. The associations were generally stronger in Chinese women (P-interaction = 0.03 for central pulse pressure) and individuals with gestational diabetes (P-interaction = 0.03 for DBP and P-interaction = 0.046 for central systolic pressure). Similar patterns of results were found when using skinfold thickness as the measure of adiposity.

    CONCLUSION: Maternal adiposity is associated with higher peripheral and central blood pressures during pregnancy. Stronger associations in Chinese women and individuals with gestational diabetes warrant further investigation.
    Matched MeSH terms: Blood Pressure*
  17. Abu-Bakar NB, Makahleh A, Saad B
    Talanta, 2014 Mar;120:47-54.
    PMID: 24468341 DOI: 10.1016/j.talanta.2013.11.081
    A fast and simple solvent microextraction technique using salting out-vortex-assisted liquid-liquid microextraction (salting out-VALLME) was developed for the extraction of furfurals (2-furfural (2-F), 3-furfural (3-F), 5-methylfurfural (5-MF) and 5-hydroxymethylfurfural (5-HMF)) and patulin (PAT) in fruit juice samples. The optimum extraction conditions for 5 mL sample were: extraction solvent, 1-hexanol; volume of extractant, 200 µL; vortex time, 45 s; salt addition, 20%. The simultaneous determination of the furfurals and PAT were investigated using high performance liquid chromatography coupled with diode array detector (HPLC-DAD). The separation was performed using ODS Hypersil C18 column (4.6 mm i.d × 250 mm, 5 μm) under gradient elution. The detection wavelengths used for all compounds were 280 nm except for 3-F (210 nm). The furfurals and PAT were successfully separated in less than 9 min. Good linearities (r(2)>0.99) were obtained within the range 1-5000 μg L(-1) for all compounds except for 3-F (10-5000 µg L(-1)) and PAT (0.5-100 μg L(-1)). The limits of detection (0.28-3.2 µg L(-1)) were estimated at S/N ratio of 3. The validated salting out-VALLME-HPLC method was applied for the analysis of furfurals and PAT in fruit juice samples (apple, mango and grape).
    Matched MeSH terms: Chromatography, High Pressure Liquid/methods
  18. Al-Fakih EA, Osman NA, Eshraghi A, Adikan FR
    Sensors (Basel), 2013 Aug 12;13(8):10348-57.
    PMID: 23941909 DOI: 10.3390/s130810348
    This study presents the first investigation into the capability of fiber Bragg grating (FBG) sensors to measure interface pressure between the stump and the prosthetic sockets of a trans-tibial amputee. FBG element(s) were recoated with and embedded in a thin layer of epoxy material to form a sensing pad, which was in turn embedded in a silicone polymer material to form a pressure sensor. The sensor was tested in real time by inserting a heavy-duty balloon into the socket and inflating it by using an air compressor. This test was conducted to examine the sensitivity and repeatability of the sensor when subjected to pressure from the stump of the trans-tibial amputee and to mimic the actual environment of the amputee's Patellar Tendon (PT) bar. The sensor exhibited a sensitivity of 127 pm/N and a maximum FSO hysteresis of around ~0.09 in real-time operation. Very good reliability was achieved when the sensor was utilized for in situ measurements. This study may lead to smart FBG-based amputee stump/socket structures for pressure monitoring in amputee socket systems, which will result in better-designed prosthetic sockets that ensure improved patient satisfaction.
    Matched MeSH terms: Transducers, Pressure*
  19. Lee YY, Wirz AA, Whiting JG, Robertson EV, Smith D, Weir A, et al.
    Gut, 2014 Jul;63(7):1053-60.
    PMID: 24064007 DOI: 10.1136/gutjnl-2013-305803
    OBJECTIVE: There is a high incidence of inflammation and metaplasia at the gastro-oesophageal junction (GOJ) in asymptomatic volunteers. Additionally, the majority of patients with GOJ adenocarcinomas have no history of reflux symptoms. We report the effects of waist belt and increased waist circumference (WC) on the physiology of the GOJ in asymptomatic volunteers.

    DESIGN: 12 subjects with normal and 12 with increased WC, matched for age and gender were examined fasted and following a meal and with waist belts on and off. A magnet was clipped to the squamo-columnar junction (SCJ). Combined assembly of magnet-locator probe, 12-channel pH catheter and 36-channel manometer was passed.

    RESULTS: The waist belt and increased WC were each associated with proximal displacement of SCJ within the diaphragmatic hiatus (relative to upper border of lower oesophageal sphincter (LOS), peak LOS pressure point and pressure inversion point, and PIP (all p<0.05). The magnitude of proximal migration of SCJ during transient LOS relaxations was reduced by 1.6-2.6 cm with belt on versus off (p=0.01) and in obese versus non-obese (p=0.04), consistent with its resting position being already proximally displaced. The waist belt, but not increased WC, was associated with increased LOS pressure (vs intragastric pressure) and movement of pH transition point closer to SCJ. At 5 cm above upper border LOS, the mean % time pH <4 was <4% in all studied groups. Acid exposure 0.5-1.5 cm above SCJ was increased, with versus without, belt (p=0.02) and was most marked in obese subjects with belt.

    CONCLUSIONS: Our findings indicate that in asymptomatic volunteers, waist belt and central obesity cause partial hiatus herniation and short-segment acid reflux. This provides a plausible explanation for the high incidence of inflammation and metaplasia and occurrence of neoplasia at the GOJ in subjects without a history of reflux symptoms.

    Matched MeSH terms: Pressure/adverse effects*
  20. Salamonsen RF, Lim E, Moloney J, Lovell NH, Rosenfeldt FL
    Artif Organs, 2015 Aug;39(8):681-90.
    PMID: 26146861 DOI: 10.1111/aor.12550
    This study in five large greyhound dogs implanted with a VentrAssist left ventricular assist device focused on identification of the precise site and physiological changes induced by or underlying the complication of left ventricular suction. Pressure sensors were placed in left and right atria, proximal and distal left ventricle, and proximal aorta while dual perivascular and tubing ultrasonic flow meters measured blood flow in the aortic root and pump outlet cannula. When suction occurred, end-systolic pressure gradients between proximal and distal regions of the left ventricle on the order of 40-160 mm Hg indicated an occlusive process of variable intensity in the distal ventricle. A variable negative flow difference between end systole and end diastole (0.5-3.4 L/min) was observed. This was presumably mediated by variable apposition of the free and septal walls of the ventricle at the pump inlet cannula orifice which lasted approximately 100 ms. This apposition, by inducing an end-systolic flow deficit, terminated the suction process by relieving the imbalance between pump requirement and delivery from the right ventricle. Immediately preceding this event, however, unnaturally low end-systolic pressures occurred in the left atrium and proximal left ventricle which in four dogs lasted for 80-120 ms. In one dog, however, this collapse progressed to a new level and remained at approximately -5 mm Hg across four heart beats at which point suction was relieved by manual reduction in pump speed. Because these pressures were associated with a pulmonary capillary wedge pressure of -5 mm Hg as well, they indicate total collapse of the entire pulmonary venous system, left atrium, and left ventricle which persisted until pump flow requirement was relieved by reducing pump speed. We suggest that this collapse caused the whole vascular region from pulmonary capillaries to distal left ventricle to behave as a Starling resistance which further reduced right ventricular output thus contributing to a major reduction in pump flow. We contend that similar complications of manual speed control also occur in the human subject and remain a major unsolved problem in the clinical management of patients implanted with rotary blood pumps.
    Matched MeSH terms: Transducers, Pressure; Ventricular Pressure
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