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Kinds of Pad Terms modified by Pad Selected AbstractsValidated HPLC method for the standardization of Phyllanthus niruri (herb and commercial extracts) using corilagin as a phytochemical markerBIOMEDICAL CHROMATOGRAPHY, Issue 6 2009Renata Colombo Abstract Phyllanthus niruri L., commonly known in Brazil as ,quebra-pedra', has long been used in the treatment of diverse diseases and especially urolithiasis. The therapeutic effects of P. niruri are attributed to various compounds present in the plant, including the hydrolysable tannin corilagin. In the present study, high-performance liquid chromatography (HPLC-/PAD) profiles of leaves and commercial extracts of P. niruri were examined and three compounds, found to be present in all of the samples studied, were isolated by open column chromatography over C18 silica gel followed by preparative HPLC. These compounds were identified by nuclear magnetic resonance as corilagin, rutin and ethyl 3,4,5-trihydroxybenzoate. Corilagin, which has been proposed as a phytochemical marker for P. niruri, was employed as an external standard in the development and validation of a rapid and efficient qualitative and quantitative HPLC assay for the analyte. The method may be applied in the standardization of herbs and phytomedicines commercialized in Brazil as quebra-pedra. Copyright © 2009 John Wiley & Sons, Ltd. [source] A combined HPLC-UV and HPLC-MS method for the identification of lignans and its application to the lignans of Linum usitatissimum L. and L. bienne Mill.,PHYTOCHEMICAL ANALYSIS, Issue 5 2006Thomas J. Schmidt Abstract A combined HPLC-UV/PAD and HPLC-ESI/MS method allowing the fast detection and identification/structural characterisation of lignans of different structural subclasses is described. Twenty-four lignans of different skeletal types were analysed and the combined information derived from their UV and ESI/MS spectra led to the identification of group characteristics that can be used to establish the structure of unknown lignans in plant samples. This method was successfully applied to the identification of lignans in crude extracts of Linum usitatissimum L. and L. bienne Mill. Copyright © 2006 John Wiley & Sons, Ltd. [source] Flow cytometric measurement of circulating endothelial cells: The effect of age and peripheral arterial disease on baseline levels of mature and progenitor populationsCYTOMETRY, Issue 2 2006Rebecca Gusic Shaffer Abstract Background: Age and cardiovascular disease status appear to alter numbers and function of circulating endothelial progenitor cells (EPCs). Despite no universal phenotypic definition, numerous studies have implicated progenitors with apparent endothelial potential in local responses to vascular injury and with cardiovascular disease in general. To further define the role of this lineage in peripheral artery disease (PAD), we developed a multiparameter flow cytometry assay to analyze multiple phenotypic definitions of progenitor cells (PCs), EPCs, and mature endothelial cells (ECs) and evaluate effects of age and PAD on baseline levels of each subset. Methods: Blood was collected from young healthy subjects (N = 9, mean age 33 ± 8 years), older healthy subjects (N = 13, mean age 66 ± 8 years), and older subjects with PAD (N = 15, mean age 69 ± 8 years). After ammonium chloride lysis, cells were stained and analyzed on a Becton-Dickinson LSR II with a 5-color antibody panel: FITC-anti-CD31, PE-anti-CD146, PE-anti-CD133, PerCP-Cy5.5-anti-CD3,-CD19,-CD33 (lineage panel), PE-Cy7-anti-CD34, and APC-anti-VEGF-R2. Viability was assessed by propidium iodide exclusion, and only viable, low to medium side scatter lineage-negative singlets were analyzed. In some studies, cells were sorted for morphological studies. Subsets were defined as indicated later. Results: Our results, using a comprehensive flow cytometric panel, indicate that CD133+, CD34+, and CD133+/CD34+ PCs are elevated in younger healthy individuals compared to older individuals, both healthy and with PAD. However, the number of EPCs and mature ECs did not significantly differ among the three groups. Assessment of endothelial colony forming units and dual acLDL-lectin staining supported the flow cytometric findings. Conclusions: We describe a comprehensive flow cytometric method to detect circulating mature and progenitor endothelial populations confirmed by conventional morphological and functional assays. Our findings suggest that aging may influence circulating levels of PCs, but not EPCs or ECs; PAD had no effect on baseline levels of any populations investigated. This study provides the basis for evaluating the potential effects of acute stress and therapeutic intervention on circulating progenitor and endothelial populations as a biomarker for cardiovascular status. © 2005 International Society for Analytical Cytology [source] Metabolic, endocrine and haemodynamic risk factors in the patient with peripheral arterial diseaseDIABETES OBESITY & METABOLISM, Issue 2002Jill J. F. Belch The morbidity and mortality associated with peripheral arterial disease (PAD) creates a huge burden in terms of costs both to the patient and to the health service. PAD is a deleterious and progressive condition that causes a marked increase in the risk of cardiovascular and cerebrovascular events. Further, PAD has a major negative impact on quality of life and mortality, and is associated with an increased risk of limb amputation. The clinical profile of patients at risk of PAD overlaps considerably with the known cardiovascular risk factors. These include, increasing age, smoking habit, diabetes, hypertension, dyslipidaemia, male sex and hyperhomocysteinaemia. For women, hormone replacement therapy appears to be associated with a reduced risk of PAD. Published PAD guidelines recommend aggressive management of risk factors, stressing the importance of lifestyle modification, antiplatelet agents, treating dyslipidaemia and diabetes. However, a large number of patients with PAD go undetected, either because they do not report their symptoms or because they are asymptomatic. It is therefore important to improve detection rates so that these patients can receive appropriate risk factor management. [source] Peripheral arterial disease in diabetes,a reviewDIABETIC MEDICINE, Issue 1 2010E. B. Jude Diabet. Med. 27, 4,14 (2010) Abstract Diabetic patients are at high risk for peripheral arterial disease (PAD) characterized by symptoms of intermittent claudication or critical limb ischaemia. Given the inconsistencies of clinical findings in the diagnosis of PAD in the diabetic patient, measurement of ankle-brachial pressure index (ABI) has emerged as the relatively simple, non-invasive and inexpensive diagnostic tool of choice. An ABI < 0.9 is not only diagnostic of PAD even in the asymptomatic patient, but is also an independent marker of increased morbidity and mortality from cardiovascular diseases. With better understanding of the process of atherosclerosis, avenues for treatment have increased. Modification of lifestyle and effective management of the established risk factors such as smoking, dyslipidaemia, hyperglycaemia and hypertension retard the progression of the disease and reduce cardiovascular events in these patients. Newer risk factors such as insulin resistance, hyperfibrinogenaemia, hyperhomocysteinaemia and low-grade inflammation have been identified, but the advantages of modifying them in patients with PAD are yet to be proven. Therapeutic angiogenesis, on the other hand, represents a promising therapeutic adjunct in the management of PAD in these patients. Outcomes after revascularization procedures, such as percutaneous transluminal angioplasty and surgical bypasses in diabetic patients, are poorer, with increased perioperative morbidity and mortality compared with that in non-diabetic patients. Amputation rates are higher due to the distal nature of the disease. Efforts towards increasing awareness and intensive treatment of the risk factors will help to reduce morbidity and mortality in diabetic patients with PAD. [source] Mild peripheral neuropathy prevents both leg muscular ischaemia and activation of exercise-induced coagulation in Type 2 diabetic patients with peripheral artery diseaseDIABETIC MEDICINE, Issue 10 2007F. Piarulli Abstract Aim, To study the influence of peripheral neuropathy on intermittent claudication in patients with Type 2 diabetes (T2DM). Methods, Twenty-five patients with T2DM were grouped according to the ankle/brachial index (ABI): 10 with ABI > 0.9 without peripheral artery disease (PAD; group T2DM) and 15 with ABI < 0.9 with PAD (group T2DM + PAD). Twelve individuals without T2DM with PAD (group PAD without T2DM) were also enrolled. Tests for peripheral neuropathy were performed in all patients. ABI, rate pressure product, prothrombin fragments 1 + 2 (F1+2), thrombin-anti-thrombin complex (TAT), and d -dimer were measured before and after a treadmill test. During exercise both initial and absolute claudication distance and electrocardiogram readings were recorded. Results, We found mild peripheral neuropathy in 20% of group T2DM and 46.7% of group T2DM + PAD (P < 0.01). After exercise, the rate pressure product increased in each group; ABI fell in T2DM + PAD (P < 0.0001) and in PAD without T2DM (P = 0.0005); the fall was greater in the latter group. Initial and absolute claudication distances were similar in PAD patients. In group T2DM + PAD, absolute claudication distance was longer in the subgroup without peripheral neuropathy (P < 0.05), whereas ABI and rate pressure products were similar. F1+2 values at rest were higher in group T2DM + PAD. After exercise, F1+2 values and TAT increased only in group PAD without T2DM. Conclusion, Only group PAD without T2DM experienced muscular ischaemia, whereas group T2DM + PAD did not. Mild peripheral neuropathy may have prevented them from reaching the point of muscular ischaemia during the treadmill test, because they stopped exercising with the early onset of pain. Reaching a false absolute claudication distance may induce ischaemic preconditioning. These findings suggest a possible protective role of mild peripheral neuropathy in T2DM patients with intermittent claudication, by preventing further activation of coagulation during treadmill testing. [source] The MTHFR C677T polymorphism confers a high risk for stroke in both homozygous and heterozygous T allele carriers with Type 2 diabetesDIABETIC MEDICINE, Issue 5 2006M. P. Hermans Abstract Objective Individuals with Type 2 diabetes are at increased risk of stroke. Plasma homocysteine (tHcy) is an independent risk factor for cardiovascular (CV) disease. The methylene,tetrahydrofolate reductase (MTHFR) gene polymorphism (thermolabile variant C677T) is associated with CV risk, partly as a result of increased Hcy, especially in homozygous subjects. Aim To relate the occurrence of the MTHFR polymorphism with stroke prevalence by examining allelic frequency and genotype distribution in 165 subjects with Type 2 diabetes studied for the presence of thermolabile C677T MTHFR mutation. Results Mean age was 67.7 years, and tHcy 18.2 µmol/l. T allele frequency was 38.5%. MTHFR genotypes were: normal (CC) 40%; heterozygous (CT) 43%; homozygous (TT) 17%. Serum levels of folic acid and B12 vitamin were within normal limits. Stroke prevalence was 14%. Sixty-four per cent of stroke-free subjects had the normal C allele vs. 46% in stroke subjects. The frequencies of genotypes (CC-CT-TT) were (%): 44-41-15 in stroke-free vs. 17-57-26 in stroke patients. Coronary (CAD) and peripheral artery disease (PAD) were common in all groups, with no differences according to genotypes. Stroke prevalence was markedly higher in genotypes CT and TT (18 and 21%) compared with CC (6%). Mean tHcy levels were higher in TT subjects. Conclusion The allelic frequency of C677T MTHFR mutation in Type 2 diabetes subjects with stroke is markedly different from that of subjects without stroke. Genotypic characteristics suggest that C677T MTHFR mutation confers a higher risk for stroke to both homozygous and heterozygous T allele carriers that cannot be ascribed solely to raised tHcy and/or lower folate status in CT subjects, nor to phenotypic expression of conventional risk factors for stroke. The impact of the MTHFR polymorphism on stroke may result from T allele-linked deleterious effects, or C allele-linked protection. Confirmatory studies are warranted, as this cohort was not randomly selected, and a type 1 error cannot be ruled out. [source] Coupling Capillary Electrophoresis and Pulsed Electrochemical DetectionELECTROANALYSIS, Issue 13 2005Carlos Abstract Pulsed electrochemical detection (PED) is an excellent method for detection of analytes that normally foul electrodes. In PED, the detection electrode is first cleaned at a high positive potential, then reactivated at a negative potential dissolving the surface oxide, and finally used to oxidize the analyte at a moderate positive potential. Due to the advantages and versatility of PED, many different variations of the detection waveform can be found in literature. This review focuses on application of PED to CE and in particular, the most commonly used modes: pulsed amperometric detection (PAD) and integrated pulsed amperometric detection (iPAD). [source] Pulsed Amperometric Detection of Histamine at Glassy Carbon Electrodes Modified with Gold NanoparticlesELECTROANALYSIS, Issue 4 2005V. Carralero Abstract Gold nanocrystal-modified glassy carbon electrodes (nAu-GCE) were prepared and used for the determination of histamine by flow injection and high performance liquid chromatography using pulsed amperometric detection (PAD) as the detection mode. Experimental variables involved in the electrodeposition process of gold from a HAuCl4 solution were optimized. A catalytic enhancement of the histamine voltammetric response was observed at the nAu-GCE when compared with that obtained at a conventional Au disk electrode, as a consequence of the microdispersion of gold nanocrystals on the GC substrate. The morphological and electrochemical characteristics of the nAu-GCE were evaluated by SEM and cyclic voltammetry. PAD using a very simple potential waveform consisting of an anodic potential (+700,mV for 500,ms) and a cathodic potential (,300,mV for 30,ms), was used to avoid the electrode surface fouling when histamine was detected under flowing conditions. Flow injection amperometric responses showed much higher Ip values and signal-to-noise ratios at the nAu-GCE than at a conventional gold disk electrode. A limit of detection of 6×10,7,mol L,1 histamine was obtained. HPLC-PAD at the nAu-GCE was used for the determination of histamine in the presence of other biogenic amines and indole. Histamine was determined in sardine samples spiked at a 50,,g g,1 concentration level, with good results. Furthermore, the chromatographic PAD method was also used for monitoring the formation of histamine during the decomposition process of sardine samples. [source] Measuring therapeutic attitudes in the prison environment: development of the Prison Attitude to Drugs scaleADDICTION, Issue 2 2003Nick Airey ABSTRACT Aims, To develop and test the validity of a scale measuring therapeutic attitudes among prison staff working with drug misusers. Design, A cross-sectional postal questionnaire study using 27 statements with a five-point Likert scale. Setting, Four prisons in the south-west of England Participants, A total of 252 prison staff (response rate 70%), including 67 for test,retest (response rate 57%). Findings, The study resulted in a three-dimensional, nine-item scale: the Prison Attitude to Drugs scale (PAD). The three subscales measure confidence in skills (four items), personal rewards (three items) and job satisfaction (two items). Test,retest correlations for the questions were above 0.7, with each factor having an internal coherence (coefficient alpha) of greater than 0.7. Conclusions, The PAD is a reliable tool that can be used in the prison environment. [source] Evaluation of the one-minute exercise test to detect peripheral arterial diseaseEUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 5 2008E. K. Hoogeveen ABSTRACT Background,, Asymptomatic peripheral arterial disease (PAD) is common amongst the elderly and is a risk factor for cardiovascular morbidity and mortality. PAD can be assessed by non-invasive tests such as the ankle/brachial pressure index (ABPI) at rest and Doppler flow velocity (DFV) scanning, but these tests may underestimate the prevalence of PAD. The aim of this study was to estimate the added value, for the detection of PAD, of the one-minute exercise test, defined as positive if the drop of the ankle systolic pressure was more than 30 mmHg. We also investigated whether the combination of the ABPI at rest and the one-minute exercise test could replace DFV scanning. Materials and methods,, We studied this in a random sample (n = 631) of a 50- to 75-year-old population. Results,, Of these subjects 11% (66/631) had an abnormal ABPI (< 0·9) and 16% (102/631) had an abnormal DFV curve. Of this sample 72% of the subjects performed a one-minute exercise test. Of all subjects 6% (27/451) had an abnormal ABPI (< 0·9) and 12% (54/451) had an abnormal DFV curve. The one-minute exercise test revealed seven cases of PAD (beyond the 67 already identified) which were not detected by an abnormal ABPI at rest and/or DFV scanning. As a result the prevalence of PAD increased by 2%. All patients with an aortoiliac or femoropopliteal obstruction had an ABPI at rest < 0·9. The sensitivity of the combination of the ABPI at rest and the one-minute exercise test to detect abnormal DFV curves was low for crural obstructions. Conclusion,, The one-minute exercise test slightly improves the detection of peripheral arterial disease in the general population. [source] Prevalence and outcome of asymptomatic carotid stenosis: a population-based ultrasonographic studyEUROPEAN JOURNAL OF NEUROLOGY, Issue 4 2002P. P. Mineva The aims of this epidemiological population-based cohort study were to examine the prevalence and outcomes of asymptomatic carotid stenosis (ACS) detected by duplex scanning and its relations to other vascular risk factors. A total of 500 volunteers, 200 men and 300 women, without signs and symptoms of cerebrovascular disease, aged 50,79 years, were enrolled in the study. The prevalence of ACS of 50% or greater was 6.4%. Only severe carotid stenosis was detected in 0.4% of the subjects examined. Significant relationships between ACS and coronary heart disease (CHD) [odds ratio (OR)=8.00], peripheral arterial disease (PAD) (OR=3.66), cigarette smoking in men (OR=4.39) and obesity in women (OR=0.31) were found. The biennial incidence rate of cerebral ischaemic events was 9.4%. A progression of ACS was revealed in 14% and a regression in 6.25% of the subjects. The patients with progressing ACS to more than 70% diameter reduction reached the end-points. Follow-up with repeated duplex scans in patients with advancing ACS of 50% or greater, especially smokers with CHD and PAD, is recommended. [source] Peripheral arterial disease in HIV-infected and uninfected womenHIV MEDICINE, Issue 8 2007A Sharma Objective Although HIV infection has been associated with increased risk of subclinical atherosclerosis and cardiovascular events, peripheral arterial disease (PAD) has not been assessed in HIV-infected patients. The objective of this study was to determine the prevalence of, and risk factors for, PAD using ankle-brachial index (ABI) measurement in HIV-infected and uninfected women. Methods ABI was determined for 335 participants in the Women's Interagency HIV Study (WIHS). A cross-sectional analysis was conducted to determine factors associated with high (,1.40) ABI. Results The prevalence of low ABI (,0.9) was 0.9% (n=3) and the prevalence of high ABI (,1.40) was 6.9% (n=23). The prevalence of low ABI was too low to allow risk factor analysis. On multivariate analysis, factors associated with high ABI were current cigarette smoking [adjusted odds ratio (ORadj) 2.53, 95% confidence interval (CI) 0.99,6.43], being underweight (ORadj 11.0, 95% CI 1.61,75.63) and being overweight (ORadj 5.40, 95% CI 1.13,25.89). Conclusions Although the prevalence of ABI ,0.9 was low in this cohort of HIV-infected and uninfected women, the prevalence of ABI ,1.40 was unexpectedly high. Further studies are indicated to determine the clinical significance of high ABI and its relation to the risk of cardiovascular events in HIV-infected women. [source] Hydro-climatic impacts on the ice cover of the lower Peace RiverHYDROLOGICAL PROCESSES, Issue 17 2008Spyros Beltaos Abstract Since the late 1960s, a paucity of ice-jam flooding in the lower Peace River has resulted in prolonged dry periods and considerable reduction in the area covered by lakes and ponds that provide habitat for aquatic life in the Peace,Athabasca Delta (PAD) region. Though major ice jams occur at breakup, antecedent conditions play a significant role in their frequency and severity. These conditions are partly defined by the mode of freezeup and the maximum thickness that is attained during the winter, shortly before the onset of spring and development of positive net heat fluxes to the ice cover. Data from hydrometric gauge records and from field surveys are utilized herein to study these conditions. It is shown that freezeup flows are considerably larger at the present time than before regulation, and may be responsible for more frequent formation of porous accumulation covers. Despite a concomitant rise in winter temperatures, solid-ice thickness has increased since the 1960s. Using a simple ice growth model, specifically developed for the study area, it is shown that porous accumulation covers enhance winter ice growth via accelerated freezing into the porous accumulation. Coupled with a reduction in winter snowfall, this effect can not only negate, but reverse, the effect of warmer winters on ice thickness, thus explaining present conditions. The present model is also shown to be a useful prediction tool, especially for extrapolating incomplete data to the end of the winter. Copyright © 2007 Crown in the right of Canada. Published by John Wiley & Sons, Ltd. [source] The role of waves in ice-jam flooding of the Peace-Athabasca DeltaHYDROLOGICAL PROCESSES, Issue 19 2007Spyros Beltaos Abstract Since the late 1960s, a paucity of ice-jam flooding in the lower Peace River has resulted in prolonged dry periods and considerable reduction in the area covered by lakes and ponds that provide habitat for aquatic life in the Peace-Athabasca Delta (PAD) region. To identify the causes of this trend, and to develop mitigation or adaptation strategies under present and future climatic conditions, it is necessary to understand the mechanisms that lead to breakup of the ice cover and jamming within the delta reach of Peace River. Because the lower Peace is extremely flat, the long-period waves caused by spring snowmelt are not generally capable of dislodging the winter ice cover, even under conditions of very high flow. The ice cover decays in place and rubble generation, an essential condition for ice jamming, does not occur. However, major jams do, on occasion, form in the middle section of the river and make their way to the delta via repeated releases and stalls. Each release generates a steep wave which can greatly amplify the hydrodynamic forces that are applied on the ice cover and bring about its dislodgment. This is quantified for the lower Peace River by applying recently developed methodology to local hydrometric data. Detailed in situ observations in the spring of 2003, and additional data from 1997 and 2002, fully corroborate this conclusion. Implications to other flat rivers of northern Canada are discussed. Copyright © 2007 Crown in the right of Canada. Published by John Wiley & Sons, Ltd. [source] Classification of hydrological regimes of northern floodplain basins (Peace,Athabasca Delta, Canada) from analysis of stable isotopes (,18O, ,2H) and water chemistryHYDROLOGICAL PROCESSES, Issue 2 2007Brent B. Wolfe Abstract We used stable isotopes (,18O and ,2H) and water chemistry to characterize the water balance and hydrolimnological relationships of 57 shallow aquatic basins in the Peace-Athabasca Delta (PAD), northern Alberta, Canada, based on sampling at the end of the 2000 thaw season. Evaporation-to-inflow ratios (E/I) were estimated using an isotope mass-balance model tailored to accommodate basin-specific input water compositions, which provided an effective, first-order, quantitative framework for identifying water balances and associated limnological characteristics spanning three main, previously identified drainage types. Open-drainage basins (E/I < 0·4; n = 5), characterized by low alkalinity, low concentrations of nitrogen, dissolved organic carbon (DOC) and ions, and high minerogenic turbidity, include large, shallow basins that dominate the interior of the PAD and experience frequent or continuous river channel connection. Closed-drainage basins (E/I , 1·0; n = 16), in contrast, possess high alkalinity and high concentrations of nitrogen, DOC, and ions, and low minerogenic turbidity, and are located primarily in the relict and infrequently flooded landscape of the northern Peace sector of the delta. Several basins fall into the restricted-drainage category (0·4 # E/I < 1·0; n = 26) with intermediate water chemistries and are predominant in the southern Athabasca sector, which is subject to active fluviodeltaic processes, including intermittent flooding from riverbank overflow. Integration of isotopic and limnological data also revealed evidence for a new fourth drainage type, mainly located near the large open-drainage lakes that occupy the central portion of the delta but within the Athabasca sector (n = 10). These basins were very shallow (<50 cm deep) at the time of sampling and isotopically depleted, corresponding to E/I characteristic of restricted- and open-drainage conditions. However, they are limnologically similar to closed-drainage basins except for higher conductivity and higher concentrations of Ca2+ and Na+, and lower concentrations of SiO2 and chlorophyll c. These distinct features are due to the overriding influence of recent summer rainfall on the basin water balance and chemistry. The close relationships evident between water balances and limnological conditions suggest that past and future changes in hydrology are likely to be coupled with marked alterations in water chemistry and, hence, the ecology of aquatic environments in the PAD. Copyright © 2006 John Wiley & Sons, Ltd. [source] Ice regime of the lower Peace River and ice-jam flooding of the Peace-Athabasca DeltaHYDROLOGICAL PROCESSES, Issue 19 2006Spyros Beltaos Abstract The Peace-Athabasca Delta (PAD) in northern Alberta is one of the world's largest inland freshwater deltas, home to large populations of waterfowl, muskrat, beaver, and free-ranging wood bison. Beginning in the mid-1970s, a paucity of ice-jam flooding in the lower Peace River has resulted in prolonged dry periods and considerable reduction in the area covered by lakes and ponds that provide a habitat for aquatic life in the PAD region. Using archived hydrometric data and in situ observations, the ice regime of the lower Peace is described and quantified, setting the stage for identification of the conditions that lead to ice-jam flooding and replenishment of Delta habitat. The first such condition is the occurrence of a mechanical, as opposed to a thermal, breakup event; second, the river flow should be at least 4000 m3/s; and third, an ice jam should form within the last 50 km of the Peace River. The type of breakup event depends on the freeze-up stage and spring flow. The former has increased as a result of flow regulation, and the latter has decreased owing to changing climatic patterns. Both trends tend to inhibit the occurrence of mechanical breakups and contribute to less frequent ice-jam flooding. Potential mitigation strategies are discussed. Copyright © 2006 Crown in the right of Canada. Published by John Wiley & Sons, Ltd. [source] Diagnosis of peripheral arterial disease in general practice: can the ankle,brachial index be measured either by pulse palpation or an automatic blood pressure device?,INTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 7 2008V. Aboyans Summary Background:, Despite its validity as a screening test for peripheral arterial disease (PAD), and its prognostic value, the ankle,brachial index (ABI) is infrequently used in primary care, probably because a Doppler device is required, along with the requisite skill for its use. We hypothesized that ABI could be accurately measured either by pulse palpation (pABI) or automatic blood pressure devices (autoABI) instead of Doppler method (dABI). Design and methods:, In 54 subjects, we compared the results and the intra-observer reproducibility of pABI to dABI, as well as the inter-observer reproducibility of both pABI and autoABI to dABI. Arm and ankle systolic pressures were measured by the three methods by two observers. The first observer repeated pABI and dABI measurements. The results were compared by the Student paired t -test. Reproducibility was assessed by the intra-class correlation coefficient of agreement (R) and the Bland and Altman method. Results:, The mean dABI obtained by the first observers was 1.03 ± 0.26 vs. a pABI of 0.85 ± 0.44 (p < 0.0001) and an autoABI of 1.09 ± 0.31 (p < 0.05). The intra-observer R -coefficient was at 0.89 for dABI vs. 0.60 for pABI (p < 0.05). The inter-observer R -coefficients were 0.79 for dABI vs. 0.40 for pABI (p < 0.05) and 0.44 for autoABI (p < 0.05). Conclusion:, Neither pulse palpation nor automatic oscillometric devices can be recommended as reliable methods for ABI measurement. [source] Citrullinated peptide and its relevance to rheumatoid arthritis: an updateINTERNATIONAL JOURNAL OF RHEUMATIC DISEASES, Issue 4 2010Stanislav LUBAN Abstract Citrullinated peptides in autoimmune diseases have been extensively studied in the last two decades. It is suggested that citrullination and the anti-citrullinated peptide antibodies (ACPA) plays a critical role in initiating inflammatory responses in autoimmune diseases, such as rheumatoid arthritis (RA). The most commonly accepted molecular mechanism for citrullinated peptides/proteins in RA is that the modified antigen resulting from cell damage or uncontrolled apoptosis could evoke an immune response leading to autoantibodies against these peptide or the whole protein. Citrullination of arginine is catalyzed by the enzyme peptidylarginine-deiminase (PAD) in the presence of calcium, changing the positively charged arginine to a polar but neutral citrulline. These citrullinated peptides/proteins and the relevant antibodies (ACPA) are important, not only in initiation of RA, but also in the diagnosis of the disease. In this evidence-based clinical review, we summarize recently published data on peptide citrullination and ACPA gauging the ability of anti-cyclic citrullinated peptide (anti-CCP) antibodies for diagnosis of RA. We also recapitulate results of studies elucidating the mechanism underlying the disease. [source] Associations Between Lower Extremity Ischemia, Upper and Lower Extremity Strength, and Functional Impairment with Peripheral Arterial DiseaseJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 4 2008Mary M. McDermott MD OBJECTIVES: To identify associations between lower extremity ischemia and leg strength, leg power, and hand grip in persons with and without lower extremity peripheral arterial disease (PAD). To determine whether poorer strength may mediate poorer lower extremity performance in persons with lower arterial brachial index (ABI) levels. DESIGN: Cross-sectional. SETTING: Academic medical centers. PARTICIPANTS: Four hundred twenty-four persons with PAD and 271 without PAD. MEASUREMENTS: Isometric knee extension and plantarflexion strength and handgrip strength were measured using a computer-linked strength chair. Knee extension power was measured using the Nottingham leg rig. ABI, 6-minute walk, and usual and fastest 4-m walking velocity were measured. Results were adjusted for potential confounders. RESULTS: Lower ABI values were associated with lower plantarflexion strength (P trend=.04) and lower knee extension power (P trend <.001). There were no significant associations between ABI and handgrip or knee extension isometric strength. Significant associations between ABI and measures of lower extremity performance were attenuated after additional adjustment for measures of strength. CONCLUSION: These results are consistent with the hypothesis that lower extremity ischemia impairs strength specifically in distal lower extremity muscles. Associations between lower extremity ischemia and impaired lower extremity strength may mediate associations between lower ABI values and greater functional impairment. [source] Dementia and Alzheimer's Disease Incidence in Relationship to Cardiovascular Disease in the Cardiovascular Health Study CohortJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 7 2005Anne B. Newman MD Objectives: To determine whether coronary artery disease, peripheral arterial disease (PAD), or noninvasive markers of cardiovascular disease (CVD) predict the onset of dementia and Alzheimer's disease (AD). Design: Longitudinal cohort study. Setting: Four U.S. communities. Participants: Men and women (N=3,602) with a brain magnetic resonance imaging (MRI) scan but no dementia were followed for 5.4 years. Participants with stroke were excluded. Measurements: Neurologists and psychiatrists classified incident cases of dementia and subtype using neuropsychological tests, examination, medical records and informant interviews. CVD was defined at the time of the MRI scan. Noninvasive tests of CVD were assessed within 1 year of the MRI. Apolipoprotein E allele status, age, race, sex, education, Mini-Mental State Examination score, and income were assessed as potential confounders. Results: The incidence of dementia was higher in those with prevalent CVD, particularly in the subgroup with PAD. The rate of AD was 34.4 per 1,000 person-years for those with a history of CVD, versus 22.2 per 1,000 person-years without a history of CVD (adjusted hazard ratio (HR)=1.3, 95% confidence interval (CI)=1.0,1.7). Rates of AD were highest in those with PAD (57.4 vs 23.7 per 100 person-years, adjusted HR=2.4, 95% CI=1.4,4.2). Results were similar with further exclusion of those with vascular dementia from the AD group. A gradient of increasing risk was noted with the extent of vascular disease. Conclusion: Older adults with CVD other than stroke had a higher risk of dementia and AD than did those without CVD. The risk was highest in people with PAD, suggesting that extensive peripheral atherosclerosis is a risk factor for AD. [source] Initial feasibility of a multi-station high resolution three-dimensional dark blood angiography protocol for the assessment of peripheral arterial diseaseJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 4 2009Georgeta Mihai PhD Abstract Purpose To evaluate the feasibility of a multi-station three dimensional (3D) T1-weighted turbo spin echo (TSE) dark-blood Sampling Perfection with Application optimized Contrasts using different flip angle Evolution sequence (T1w-SPACE), to assess aorta, iliac, and superficial femoral (SFA) arteries (inflow vessels) by comparing it with a multi-station contrast enhanced MR angiography (CE-MRA) with identical resolution. Materials and Methods A total of 6 volunteers and 14 peripheral arterial disease (PAD) patients were included in the study. Abdominal and thigh T1w-SPACE and lower leg time-resolved MRA (TR-MRA) with low dose contrast were followed by 3-station CE-MRA. Quantitative measurements of lumen area at 17 locations from T1w-SPACE and CE-MRA were obtained. Additionally, vessel wall areas at the same locations were obtained from the T1w-SPACE images. Results Quantitative comparison of lumen areas with T1w-SPACE and CE-MRA revealed strong correlation between the two techniques and strong inter-observer agreement for each of the two imaging methods (r > 0.9; P < 0.001). Localized vessel wall area measurements obtained in PAD patients were significantly greater compared with those obtained in normal volunteers (mean difference 43.75 ± 12.46 mm2; P < 0.001). Stenosis severity obtained from T1w-SPACE localized measurements showed significant arterial area stenosis in PAD patients. Conclusion T1w-SPACE imaging of inflow vessels is feasible, and in addition to CE-MRA has the ability to assess atherosclerotic plaque and vascular remodeling. J. Magn. Reson. Imaging 2009;30:785,793. © 2009 Wiley-Liss, Inc. [source] Abnormal accumulation of citrullinated proteins catalyzed by peptidylarginine deiminase in hippocampal extracts from patients with Alzheimer's diseaseJOURNAL OF NEUROSCIENCE RESEARCH, Issue 1 2005Akihito Ishigami Abstract Citrullinated proteins are the products of a posttranslational process in which arginine residues undergo modification into citrulline residues when catalyzed by peptidylarginine deiminases (PADs) in a calcium ion-dependent manner. In our previous report, PAD2 expressed mainly in the rat cerebrum became activated early in the neurodegenerative process. To elucidate the involvement of protein citrullination in human neuronal degeneration, we examined whether citrullinated proteins are produced during Alzheimer's disease (AD). By Western blot analysis with antimodified citrulline antibody, citrullinated proteins of varied molecular weights were detected in hippocampal tissues from patients with AD but not normal humans. Two of the citrullinated proteins were identified as vimentin and glial fibrillary acidic protein (GFAP) by using two-dimensional gel electrophoresis and MALDI-TOF mass spectrometry. Interestingly, PAD2 was detected in hippocampal extracts from AD and normal brains, but the amount of PAD2 in the AD tissue was markedly greater. Histochemical analysis revealed citrullinated proteins throughout the hippocampus, especially in the dentate gyrus and stratum radiatum of CA1 and CA2 areas. However, no citrullinated proteins were detected in the normal hippocampus. PAD2 immunoreactivity was also ubiquitous throughout both the AD and the normal hippocampal areas. PAD2 enrichment coincided well with citrullinated protein positivity. Double immunofluorescence staining revealed that citrullinated protein- and PAD2-positive cells also coincided with GFAP-positive cells, but not all GFAP-positive cells were positive for PAD2. As with GFAP, which is an astrocyte-specific marker protein, PAD2 is distributed mainly in astrocytes. These collective results, the abnormal accumulation of citrullinated proteins and abnormal activation of PAD2 in hippocampi of patients with AD, strongly suggest that PAD has an important role in the onset and progression of AD and that citrullinated proteins may become a useful marker for human neurodegenerative diseases. © 2005 Wiley-Liss, Inc. [source] Women With Primary Antibody Deficiencies Requiring IgG Replacement Therapy: Their Perception of Prenatal Care During PregnancyJOURNAL OF OBSTETRIC, GYNECOLOGIC & NEONATAL NURSING, Issue 5 2004Susanne Hansen RN Objective: To investigate how a group of women with primary antibody deficiencies (PAD) and receiving replacement therapy with IgG experienced the care they received in their prenatal clinics in relation to PAD and IgG therapy. Design: An exploratory study using a written questionnaire. Setting: The study originates from an immunodeficiency unit but evaluates care experienced at prenatal clinics. Participants: Nine women (25,43 years) attending an immunodeficiency unit and who fulfilled inclusion criteria for simultaneously having PAD, replacement IgG therapy, and full-term pregnancy (the latter within the past 5 years). Main outcome: Women's perception of the response of midwives and physicians at their prenatal clinics to their PAD and IgG therapy during pregnancy. Results: Women perceived that the obstetricians and the midwives had insufficient knowledge about PAD and IgG replacement therapy. Two women reported that their IgG therapy during pregnancy had been questioned. All nine women felt marginalized and unheard by staff regarding their PAD and need for IgG therapy. However, the women were satisfied with the checkups regarding the pregnancy as such. Conclusions: This study is the first attempt to investigate the prenatal experience of women with PAD (Search of PubMed, 1980 to present, including search terms primary immunodeficiency, pregnancy, and prenatal care). This study demonstrates that increased knowledge about PAD and IgG replacement therapy among midwives and physicians working in prenatal care clinics is needed. This can prevent misleading advice that puts the health of the mother and her fetus at risk. Sensitizing staff about this special group of women can create conditions in which women feel respected, heard, and satisfied with their prenatal care. [source] Altered Impulse Control in Alcohol Dependence: Neural Measures of Stop Signal PerformanceALCOHOLISM, Issue 4 2009Chiang-shan Ray Li Background:, Altered impulse control has been implicated in the shaping of habitual alcohol use and eventual alcohol dependence. We sought to identify the neural correlates of altered impulse control in 24 abstinent patients with alcohol dependence (PAD), as compared to 24 demographics matched healthy control subjects (HC). In particular, we examined the processes of risk taking and cognitive control as the neural endophenotypes of alcohol dependence. Methods:, To this end, functional magnetic resonance imaging (fMRI) was conducted during a stop signal task (SST), in which a procedure was used to elicit errors in the participants. The paradigm allowed trial-by-trial evaluation of response inhibition, error processing, and post-error behavioral adjustment. Furthermore, by imposing on the subjects to be both fast and accurate, the SST also introduced a distinct element of risk, which participants may or may not avert during the task. Brain imaging data were analyzed with Statistical Parametric Mapping in covariance analyses accounting for group disparity in general performance. Results:, The results showed that, compared to HC, PAD demonstrated longer go trial reaction time (RT) and higher stop success rate (SS%). HC and PAD were indistinguishable in stop signal reaction time (SSRT) and post-error slowing (PES). In a covariance analysis accounting for go trial RT and SS%, HC showed greater activity in the left dorsolateral prefrontal cortex than PAD, when subjects with short and long SSRT were contrasted. By comparing PAD and HC directly during stop errors (SE), as contrasted with SS, we observed greater activity in PAD in bilateral visual and frontal cortices. Compared to HC, PAD showed less activation of the right dorsolateral prefrontal cortex during PES, an index of post-error behavioral adjustment. Furthermore, PAD who showed higher alcohol urge at the time of the fMRI were particularly impaired in dorsolateral prefrontal activation, as compared to those with lower alcohol urge. Finally, compared to HC subjects, PAD showed less activity in cortical and subcortical structures including putamen, insula, and amygdala during risk-taking decisions in the SST. Conclusion:, These preliminary results provided evidence for altered neural processing during impulse control in PAD. These findings may provide a useful neural signature in the evaluation of treatment outcomes and development of novel pharmacotherapy for alcohol dependence. [source] Analog pixel array detectorsJOURNAL OF SYNCHROTRON RADIATION, Issue 2 2006A. Ercan X-ray pixel array detectors (PADs) are generally thought of as either digital photon counters (DPADs) or X-ray analog-integrating pixel array detectors (APADs). Experiences with APADs, which are especially well suited for X-ray imaging experiments where transient or high instantaneous flux events must be recorded, are reported. The design, characterization and experimental applications of several APAD designs developed at Cornell University are discussed. The simplest design is a `flash' architecture, wherein successive integrated X-ray images, as short as several hundred nanoseconds in duration, are stored in the detector chips for later off-chip digitization. Radiography experiments using a prototype flash APAD are summarized. Another design has been implemented that combines flash capability with the ability to continuously stream X-ray images at slower (e.g. milliseconds) rates. Progress is described towards radiation-hardened APADs that can be tiled to cover a large area. A mixed-mode PAD, design by combining many of the attractive features of both APADs and DPADs, is also described. [source] The factor II G20210A gene polymorphism, but not factor V Arg506Gln, is associated with peripheral arterial disease: results of a case,control studyJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 8 2004J-L. Reny Summary.,Background: The FIIG20210A polymorphism has been associated with arterial wall thickness and atherothrombotic diseases in selected subgroups. The FVArg506Gln polymorphism does not seem to be associated with arterial diseases. Few data are available on these polymorphisms and the risk of peripheral arterial disease (PAD). Objectives: To study the association between the FIIG20210A and FVArg506Gln polymorphisms and PAD and its clinical severity. To examine the potential interactions with traditional vascular risk factors. Patients and methods: We studied 184 consecutive male patients under 70 years of age with symptomatic PAD and 330 age-matched male controls free of symptomatic PAD and with no cardiovascular history. We evaluated the FIIG20210A and FVArg506Gln polymorphisms in all subjects. Results: Mean age was 57.1 ± 7.2 years (cases) and 56.7 ± 7.6 years (controls). The FII20210A allele was more frequent in PAD patients with odds ratios (OR) of 3.77 (1.39,10.2) in univariate analysis and 4.30 (1.3,14.7) after adjustment for diabetes, smoking, hypertension and hypercholesterolemia. In smokers or past smokers the magnitude of the association was markedly increased but there was no evidence of an interaction between tobacco exposure and FIIG20210A. In case subjects, the FII20210A allele was also associated with critical ischemia [OR = 4.1 (1.1,15.7), P = 0.039 in multivariate analysis]. FVArg506Gln was not associated with PAD [OR = 0.65 (0.27,1.54) and 0.77 (0.28,2.1) in univariate and multivariate analyses, respectively]. Conclusions: The FIIG20210A gene polymorphism may be a risk factor for PAD and its severity. In contrast, the FVArg506Gln polymorphism is not associated with PAD. [source] Analysis of pharmaceutical samples of Resina Draconis by HPLC-PADPHYTOCHEMICAL ANALYSIS, Issue 6 2008Wenjun Gong Abstract Introduction: The quality evaluation of traditional Chinese medicine (TCM) represents a particular challenge owing to the complexity of the matrix, which renders separation and identification of the individual components extremely difficult. In recent years, fingerprinting of TCMs has played a dominant role in quality control. Resina Draconis was authorised as a new TCM in 1991, but a satisfactory HPLC fingerprint method for this preparation has not yet been published. Objective: To develop a simple and reliable protocol for the quality control of Resina Draconis using an HPLC-PAD method. Methodology: The TCM was extracted with methanol at room temperature. Chromatography was carried out using a Lichrospher C18 column eluted with a linear gradient of acetonitrile (A) and water containing 0.1% phosphoric acid (B), initially at 30:70 (A:B) and changing to 60:40 in 90 min. UV (PAD) spectra were acquired in the range 210,400 nm. Results: Four chromatograms of samples of Resina Draconis obtained from different pharmaceutical factories showed 20 peaks in common. The average chromatogram was taken as a template from which the correlation coefficients and cosine ratios of the samples were determined. Whereas the contents of individual components in each sample were different, overall the samples were extremely similar one to another, and the products from different pharmaceutical factories were consistent. Conclusion: A reliable and validated HPLC method has been developed for the fingerprint analysis of Resina Draconis that can be applied for the quality control of this TCM. Copyright © 2008 John Wiley & Sons, Ltd. [source] Analysis of Rhizoma Polygoni Cuspidati by HPLC and HPLC-ESI/MSPHYTOCHEMICAL ANALYSIS, Issue 5 2007Tao Yi Abstract An HPLC method with photodiode array detection (PAD) and ESI/MS detection was developed for the qualitative and quantitative analysis of the major chemical constituents of the dried rhizome of Polygonum cuspidatum Sieb. et Zucc. (Rhizoma Polygoni Cuspidati; Chinese name Hu-Zhang). Based on the chromatographic separation on an Altima C18 column using 0.5% aqueous acetic acid and acetonitrile as the mobile phase, nine compounds, including stilbenes, stilbene glucosides, anthraquinones and anthraquinone glucosides, were identified by online ESI/MS analysis and seven were quantified by HPLC-PAD. A full validation of the method including sensitivity, linearity, repeatability and recovery was conducted. Linear calibration was achieved over the concentration range 1,200 mg/L with R2 > 0.999, whilst the limits of detection ranged from 0.51 to 1.57 ng. Repeatability was evaluated by intra- and inter-day assays and the RSD value was within 1.79%. Recoveries of the quantified compounds were within the range 96.0,100.1% with RSD values of less than 2.2%. Five samples of Rhizoma Polygoni Cuspidati from different regions were analysed using the developed method. The major constituents piceid, resveratrol, emodin-8- O - , - d -glucoside and emodin were selected to provide an index for the quality assessment of the herbal drug. Copyright © 2007 John Wiley & Sons, Ltd. [source] Quantitative analysis of polymeric proanthocyanidins in birch leaves with normal-phase HPLCPHYTOCHEMICAL ANALYSIS, Issue 3 2006Maarit Karonen Abstract The proanthocyanidin composition and content in the leaves of nine birch species (Betula albosinensis, B. ermanii, B. maximowicziana, B. nana, B. papyrifera, B. pendula, B. platyphylla, B. pubescens, and B. pubescens ssp. czerepanovii) were studied with different methods including colorimetric assay, HPLC coupled with PAD or ESI/MS and NMR. Total proanthocyanidin content was determined using the acid butanol assay. A normal phase-HPLC method was applied for the analysis of polymeric proanthocyanidins. The content of polymeric proanthocyanidins was estimated from a late eluting peak in the chromatogram. With this HPLC method, quantitative analysis of polymeric proanthocyanidins could be performed directly from leaf extracts: no additional purification or preparation steps were required. It was shown that birch leaves contained mainly polymeric proanthocyanidins with a degree of polymerisation greater than 10. Total proanthocyanidin content (expressed as dry weight) was found to vary from 44 mg/g (B. papyrifera) to 145 mg/g (B. nana), and polymeric proanthocyanidin content from 39 mg/g (B. pendula) to 119 mg/g (B. nana). Copyright © 2006 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||||||||||||||||||||