Four methods for determining uric acid compared with a candidate reference method.

1982 ◽  
Vol 28 (10) ◽  
pp. 2098-2100 ◽  
Author(s):  
R J Elin ◽  
E Johnson ◽  
R Chesler

Abstract Uric acid as measured in serum by three different uricase (EC 1.7.3.3) methods (aca, Ektachem, and SMAC) and by the SMAC method with phosphotungstic acid was compared with a candidate Reference Method for uric acid. Serum specimens from 83 patients (uric acid concentrations, 19 to 141 mg/L) were analyzed by all five methods. Results were compared by using linear regression analysis, and the mean difference between results by the candidate Reference Method and the four other methods was calculated. Compared with the candidate Reference Method, the aca method gave the smallest deviation from zero for the intercept and the smallest mean difference, and the SMAC phosphotungstic acid method showed a slope closest to unity. The SMAC uricase method had the largest intercept and greatest deviation of the slope from unity.

2021 ◽  
Vol 28 (Supplement_1) ◽  
Author(s):  
M Chlabicz ◽  
M Paniczko ◽  
J Jamolkowski ◽  
P Sowa ◽  
M Lapinska ◽  
...  

Abstract Funding Acknowledgements Type of funding sources: Public Institution(s). Main funding source(s): Medical University of Bialystok, Poland Introduction A low thigh circumference is associated with an increased risk of high blood pressure, diabetes, cardiovascular diseases, and total mortality. Objectives The aim of the study was to investigate the relationship between the thigh circumference and cardiovascular (CV) risk classes, and to assess what type of tissue, adipose tissue or muscle tissue affects the thigh circumference. Methods The longitudinal, population-based, Polish study was conducted in 2017-2020. A total of 931 individuals aged 20-79 were analyzed. Pol-SCORE system was used to assess the 10-year risk of fatal CV based on the following risk factors: age, gender, smoking, systolic blood pressure, and total cholesterol for individuals aged 40-70.  Then, CV risk classes were assessed using the 2019 ESC/EAS guidelines. The measurement of thigh circumference were performed directly below the gluteal fold of the thigh. Both thighs were measured and the mean value was calculated as the final thigh circumference. Body composition was assessed using Dual Energy X-ray Absorptiometry (DEXA). Results The mean age was 49.1 ± 15.5 years and 43.2% male. The mean thigh circumference was 58.2 ± 5.9 cm, the mean legs fat mass was 7.7 ± 2.8kg, and the mean legs lean mass was 16.9 ± 4.0kg. Lower thigh circumference was associated with higher CV risk classes in univariate linear regression analysis (β -0.516, p = 0.002), as well adjusted by age and sex (β -0.839, p = 0.008), adjusted by age, sex, BMI (β -0.886, p <0.001), and age, sex, WHR (β -0.988, p <0.001). In linear regression analysis legs adipose tissue and muscle tissue were related to the thigh circumference independently of CV risk classes (Model 1) and Pol-SCORE value (Model 2). However, fatty tissue (Model 1: β 0.746, p < 0.001; Model 2: β 0.749, p < 0.001) affects the thigh circumference more than the muscle tissue (Model 1: β 0.479, p < 0.001; Model 2: β 0.442, p < 0.001) (Fig. 1). Conclusion Smaller thigh circumference was associated with higher CV risk classes. Thigh circumference was more influenced by adipose tissue than by muscle tissue, regardless of the Pol-SCORE  or CV risk classes. Table 1. Variable Model 1 Model 2 Beta p R2 Beta p R2 Legs fat mass 0.746 <0.001 0.785 0.749 <0.001 0.760 Legs lean mass 0.479 <0.001 0.785 0.442 <0.001 0.760 Model 1: adjusted for Cardiovascular risk classesModel 2: adjusted for Pol-SCOREResults of the linear regression analysis thigh circumference in the general population Abstract Figure 1.


Irriga ◽  
2008 ◽  
Vol 13 (3) ◽  
pp. 339-354 ◽  
Author(s):  
José Eduardo Pitelli Turco ◽  
José Carlos Barbosa

AVALIAÇÃO DE DUAS ESTAÇÕES METEOROLÓGICAS AUTOMATIZADAS, PARA ESTIMATIVA DIÁRIA DA EVAPOTRANSPIRAÇÃO DE REFERÊNCIA OBTIDA PELO MÉTODO DE PENMAN-MONTEITH  José Eduardo Pitelli Turco1; José Carlos Barbosa21Departamento de Engenharia Rural, Faculdade de Ciências Agrária e Veterinária, Universidade Estadual Paulista, Câmpus de Jaboticabal, Jaboticabal, SP, [email protected] de Ciências Exatas, Faculdade de Ciências Agrária e Veterinária, Universidade Estadual Paulista, Câmpus de Jaboticabal, Jaboticabal, SP  1        RESUMO              A finalidade deste trabalho foi a avaliação de estações meteorológicas automatizadas da marca Davis Instruments e Campbell Scientific, procurando detectar possíveis diferenças nas suas medições e estimativas. Foi, também, avaliada, nas duas estações, a integridade dos dados meteorológicos para estimativa da ETo. Os dados meteorológicos avaliados foram os seguintes: radiação solar global, saldo de radiação, temperatura do ar, umidade do ar, velocidade do vento e precipitação pluviométrica. O método de estimativa diária da evapotranspiração de referência avaliado foi o de Penman-Monteith, recomendado pela FAO como método padrão para estimar a ETo. As estações meteorológicas automatizadas da marca Davis Instruments e Campbell Scientific foram instaladas em uma área experimental do Departamento de Engenharia Rural da FCAV/UNESP, Campus de Jaboticabal, SP. Os dados foram coletados diariamente e analisados estatisticamente, por meio de análise de regressão. Foi aplicada uma técnica que verifica a integridade dos dados meteorológicos para estimativa da evapotranspiração de referência. O resultado da avaliação das duas estações, utilizando-se análise de regressão linear, mostra que as estimativas diárias da evapotranspiração de referência (ETo) apresentam diferenças aceitáveis. Aplicando a técnica que verifica a integridade dos dados meteorológicos, verificou-se que os dados de umidade relativa das duas estações e de precipitação da Campbell não foram de boa qualidade. UNITERMOS: evapotranspiração, estações automatizadas, intercomparação.  TURCO, J. E. P.; BARBOSA, J. C. TWO AUTOMATIC WEATHER  STATIONS  METEOROLOGICAL DATA EVALUATION BY  PENMAN-MONTEITH REFERENCE EVAPOTRANSPIRATION METHOD  2        ABSTRACT The objective of this study was to evaluate and compare measurements and estimates from Davis and Campbell Scientific Instruments in two automatic weather stations. Integrity of meteorological data for estimates of evapotranspiration of reference crop (ETo) from both stations was also evaluated. The following meteorological data were evaluated: air temperature, air humidity, wind speed, precipitation, net radiation and global solar radiation. The Penman-Monteith reference method to estimate ETo was evaluated daily. The weather stations were set up in an experimental area of the Rural Engineering Department- FACV/UNESP, in Jaboticabal, State of Sao Paulo. Data were collected daily and statistical analysis was performed using linear regression analysis. The integrity of meteorological data to estimate ETo was evaluated. The results of the study in the stations using linear regression analysis showed that daily estimates for ETo had acceptable differences. The technique which evaluates the integrity of meteorological data revealed that data of relative humidity from both stations and of precipitation using Campbell Instruments were not good.           KEY WORDS: evapotranspiration, automatic weather station, intercomparison


2019 ◽  
Vol 43 (2) ◽  
pp. 67-76
Author(s):  
Simona Storti ◽  
Elena Battipaglia ◽  
Maria Serena Parri ◽  
Andrea Ripoli ◽  
Stefania Lombardi ◽  
...  

Abstract Background Visual inspection is the most widespread method for evaluating sample hemolysis in hemostasis laboratories. The hemolysis index (HI) was determined visually (visual index, VI) and measured on an ACL TOP 750 (IL Werfen) system with a hemolysis-icterus-lipemia index (HIL) module. These values were compared with those measured on clinical chemistry systems Unicel DXC600 and AU680 and with quantitation of free-hemoglobin (Hb) performed by a spectrophotometric measurement method (SMM). Methods The HI was measured in 356 sodium citrate plasma samples, 306 of which were visibly hemolyzed to varying degrees and 50 were not hemolyzed. The analytical performance of each method was evaluated. Results Linear regression analysis, calculated between SMM and the other systems in the study, returned coefficients of determination r2 = 0.853 (AU680), r2 = 0.893 (DXC600) and r2 = 0.917 (ACL TOP 750). An r2 = 0.648 was obtained for linear regression analysis between VI and ACL TOP 750. In addition, ACL TOP 750 showed an excellent correlation in multivariate analysis (r2 = 0.958), showing good sensitivity (0.939) and specificity (0.934) and a diagnostic accuracy of 94%. By comparison, DXC600 and AU680 showed coefficients of determination of 0.945 and 0.923, respectively. A cut-off was set at 0.15 g/L free-Hb, as determined by the automated method, such that any hemostasis samples measuring above this threshold should not be analyzed. Based on this criterion, samples were classified as accepted or rejected, and the number of samples discarded during VI or ACL TOP 750 measurements was compared. Conclusions This study confirmed that hemostasis laboratories should consider introducing an objective, automated and standardized method to check samples for hemolysis. By relying solely on visual inspection, up to 50% of samples could be unnecessarily rejected. The ACL TOP 750 system demonstrated a satisfactory analytical performance, giving results comparable to those of the reference method.


1989 ◽  
Vol 56 (4) ◽  
pp. 665-668 ◽  
Author(s):  
María A. Esteban ◽  
Andrés Marcos

SummaryBy linear regression analysis, a highly significant negative correlation (r = −0·96) was found between the mean ash concentration values (g/100 g moisture) and water activity (aw) of six types of processed cheeses (low-fat, semi-fat, fat, extra-fat, double fat and special). The regression equation aw = 0·9951 − 0·0032* (ash), applied to 40 cheese samples, yielded aw values which differed by < 0·005 aw units from those measured experimentally in 75% of the samples. The maximum differences between the calculated and experimental aw values (found in only two samples) were ±0·01 aw units.


2018 ◽  
Vol 11 (1) ◽  
pp. 41
Author(s):  
Runa Laila ◽  
Begum Nasrin ◽  
Shayela Shamim ◽  
Md. Mozammel Hoque

<p class="Abstract">This study was conducted to evaluate the association of serum cancer antigen (CA-125) level with the severity of pelvic endometriosis. Seventy diagnosed cases of pelvic endometriosis were included in this study. The CA-125 level was estimated in all these patients, cutoff value of the serum CA-125 level was considered 35.0 U/mL. The correlations between serum CA-125 and different stages of endometriosis were evaluated by linear regression analysis. In Stage I of endometriosis, the mean serum CA-125 level was 21.8 ± 15.1 U/mL, in Stage II 26.0 ± 17.3 U/mL, in Stage III 83.2 ± 48.9 U/mL and in Stage IV 117.0 ± 41.6 U/mL. A significant positive correlation (r=0.729; p=0.001) was found between the serum CA-125 and different stages of endometriosis.</p>


2019 ◽  
Vol 2019 ◽  
pp. 1-6 ◽  
Author(s):  
Yuki Hashimoto ◽  
Wataru Saito ◽  
Yuka Hasegawa ◽  
Kousuke Noda ◽  
Susumu Ishida

Purpose. To investigate relationships between total thickness and the thickness of inner and outer layers in the choroid during regression in patients with multiple evanescent white dot syndrome (MEWDS). Methods. This retrospective observational case series included 15 unilaterally affected eyes and 13 unaffected fellow eyes from 15 MEWDS patients (4 men and 11 women; mean age, 37.6 ± 17.6 years). Using enhanced depth imaging optical coherence tomography, whole, inner, and outer choroidal layer thicknesses at the fovea and perifovea were manually measured at the initial visit and at 1 and 3 months after the initial visit. The mean thickness values of the layers were compared at each stage. Results. With regression of MEWDS, the mean subfoveal whole and inner choroidal layer thicknesses significantly decreased at 1 and 3 months compared to baseline values in MEWDS eyes (P=0.01 and P<0.0001, respectively), but not in fellow eyes. The outer layer in MEWDS eyes tended to thin. Changes in the inner and outer layers at the perifovea in MEWDS eyes also showed the same trends. Simple linear regression analysis revealed significant positive correlations in choroidal thickness changes between the whole and inner layers (R = 0.53, P=0.04) and between the whole and outer layers (R = 0.91, P<0.0001) from baseline to 3 months. Multiple linear regression analysis revealed that choroidal thickness changes in the whole layer were significantly correlated with those in the inner (β = 0.51, P<0.0001) and outer (β = 0.73, P<0.0001) layers. Conclusion. The inner choroidal layer significantly thinned with regression of MEWDS, correlating with the thinning of total choroidal thickness. These results suggest that MEWDS lesions in the choroid are likely to lie mainly in the inner layer.


2021 ◽  
Vol 8 ◽  
Author(s):  
Xuhao Chen ◽  
Ying Hong ◽  
Haohao Di ◽  
Qianru Wu ◽  
Di Zhang ◽  
...  

Purpose: To investigate the relationship between retinal microvasculature changes and intraocular pressure (IOP) for ocular hypertension (OHT) patients and further assess the factors associated with retinal microcirculation changes.Methods: This was a single-center prospective study designed for OHT patients, which consisted of two visits. After collecting baseline data of those who met the eligibility criteria, these patients were treated with latanoprost 0.005% ophthalmic solution for 4 weeks. Peripapillary vessel density (VD) of radial peripapillary capillaries (RPC) layer, macular VD in both superficial and deep layers, and foveal avascular zone (FAZ) area were measured by optical coherence tomography angiography (OCTA) before and after the treatment. We compared the changes in IOP and VD among the two visits by paired-sample t-test. Bonferroni correction was applied. Factors associated with VD changes were analyzed by linear regression analysis.Results: Thirty-four eyes of thirty-four patients were included. The mean IOP decreased by 6.5 ± 2.2 mmHg (p &lt; 0.001). The peripapillary RPC VD increased significantly from 51.8 ± 2.5 to 53.0 ± 3.1% (Adjusted-p = 0.012). We found no significant difference in detailed sectors of the peripapillary region after correction. In the macular area, both the superficial and deep layers in foveal (superficial: 0.2 ± 1.9%, p = 0.523; deep: 0.0 ± 2.3%, p = 0.969) and parafoveal (superficial: 0.3 ± 3.0%, p = 0.565; deep: 0.5 ± 3.1%, p = 0.423) VD remained unchanged. The decrease of the mean FAZ area was insignificant (p = 0.295). The percentage of IOP reduction (β = 0.330, p = 0.031) and the baseline RNFL thickness (β = 0.450, p = 0.004) significantly correlated with the percentage of peripapillary RPC VD improvement in the multivariate linear regression analysis.Conclusion: The peripapillary VD in OHT patients increased after the reduction of IOP. The mild change of IOP did not alter the microcirculation in the macula. In addition, the percentage of IOP change and the baseline RNFL thickness were independent factors for the peripapillary RPC VD improvement.


2012 ◽  
Vol 20 (3) ◽  
pp. 462-468 ◽  
Author(s):  
Ana Paula Sayuri Sato ◽  
Elizabeth Fujimori

This study described the nutritional status of 228 pregnant women and the influence of this on birth weight. This is a retrospective study, developed in a health center in the municipality of São Paulo, with data obtained from medical records. Linear regression analysis was carried out. An association was verified between the initial and final nutritional status (p<0.001). The mean of total weight gain in the pregnant women who began the pregnancy underweight was higher compared those who started overweight/obese (p=0.005). Weight gain was insufficient for 43.4% of the pregnant women with adequate initial weight and for 36.4% of all the pregnant women studied. However, 37.1% of those who began the pregnancy overweight/obese finished with excessive weight gain, a condition that ultimately affected almost a quarter of the pregnant women. Anemia and low birth weight were uncommon, however, in the linear regression analysis, birth weight was associated with weight gain (p<0.05). The study highlights the importance of nutritional care before and during pregnancy to promote maternal-infant health.


2008 ◽  
Vol 20 (6) ◽  
pp. 295-299 ◽  
Author(s):  
Erhan Kurt ◽  
Ilhan Karacan ◽  
Nihal Ozaras ◽  
Gazi Alatas

Objective:The aims of this study were to determine the dominant affective temperament changes in stroke survivors and whether temperament affects the disability.Methods:A total of 63 stroke patients were included in this study. Temperament Evaluation of Memphis, Pisa, Paris and San Diego Autoquestionnaire was used to determine the dominant affective temperament (depressive, hyperthymic, cyclothymic, irritable or anxious). The disability level was measured with the Barthel index (BI).Results:Depressive temperament (17.5%) and anxious temperament (12.7%) were the most common dominant affective temperaments. The frequencies of irritable, cyclothymic and hyperthymic temperaments were 4.8, 3.2 and 0%, respectively. The mean BI score was 78.1 ± 18.3 in patients with depressive temperament and 67.4 ± 28.4 in patients without depressive temperament (p = 0.403). The mean BI score was 78.1 ± 15.3 in patients with anxious temperament and 68.0 ± 28.3 in patients without anxious temperament (p = 0.541). Multiple linear regression analysis indicated that BI score was not associated with affective temperament changes.Conclusion:The results of the current study suggest that depressive and anxious temperaments are the most common affective temperaments and that there appears to be no association between disability level and dominant affective temperament in stroke survivors.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 4575-4575
Author(s):  
Daniel J. Lachant ◽  
Kanu P. Sharan ◽  
Andres Ferber ◽  
Robert Somer ◽  
Generosa Grana ◽  
...  

Abstract Aromatase inhibitors (AI) block the conversion of testosterone and androstenedione to the estrogen estrone by inhibiting the aromatase enzyme complex. AI are used to treat estrogen receptor positive (ER+) breast cancer in postmenopausal women. With AI therapy, estrogen levels decrease to 85–95% of baseline. In women with metastatic disease, androstenedione levels do not increase. We have evaluated 2 women for polycythemia during AI therapy. Case 1 is 52 years old with stage II breast cancer treated with lumpectomy, TAC × 6 and radiation. Tamoxifen was started 4 months later. The mean hemoglobin during 6 months of tamoxifen was 14.0±0.1 gm/dl. When switched to exemestane, the mean hemoglobin over the next 24 months was 16.1±0.5 gm/dl (Mann-Whitney, p&lt;0.003). Case 2 is an 80 year old with stage I breast cancer treated with lumpectomy followed by radiation. Her baseline hemoglobin was 13.8 gm/dl. 26 months after starting exemestane, her hemoglobin reached 18.0 gm/dl. After extensive evaluation, neither patient met the criteria for polycythemia vera and no etiology for secondary polycythemia was found. The presumption was that the temporal increase in hemoglobin may be due to AI therapy. Previous clinical trials have not reported an increase in hemoglobin in women receiving AI therapy for breast cancer. However, given the dramatic increase in hemoglobin in our 2 patients, we wished to test the hypothesis that inhibition of aromatase may lead to an increase in hemoglobin in postmenopausal women receiving AI therapy for breast cancer. The Cooper University Hospital Tumor Registry was used as a source of potential subjects. Women over the age of 50 years, diagnosed with ER+ nonmetastatic breast cancer between 2002 and 2006 were identified. Women included for study were postmenopausal, and treated with breast surgery +/− local radiation. Women receiving chemotherapy were excluded because of the potential effect of chemotherapy or therapeutic erythropoietin on the hemoglobin level. In order to be included for study, women needed to have a hemoglobin prior to surgery or prior to starting anti-estrogen therapy and at least 3 hemoglobin measurements over a minimum of 12 months after starting anti-estrogen therapy. AI included anastrozole and exemestane. Of 123 charts available for review, 82 had inadequate data for analysis. 27 evaluable women received only an AI. The mean age was 67±8 years and 67% were stage I. The mean hemoglobin before and during AI therapy was 13.7±0.4 and 13.2±1.1 gm/dl, respectively (Mann Whitney, p&lt;0.09). 3/27 had an increase in hemoglobin after starting AI therapy by linear regression analysis (r ≥ 0.60). The increase in hemoglobin ranged from 0.9 to 1.1 gm/dl. As a control group, 11 women received tamoxifen rather than an AI. Mean age was 59±8 years and 54% were stage I. The mean hemoglobin before and during tamoxifen therapy was 13.0±1.0 and 12.8±0.8 gm/dl, respectively (Mann Whitney, p=0.53). 0/11 had an increase in hemoglobin by linear regression analysis (r &gt; 0.60). 2 additional women received tamoxifen which was subsequently changed to an AI, 1 of whom had a mean hemoglobin of 12.9±0.3 gm/dl on tamoxifen which increased to 14.9±0.4 gm/dl on exemestane (Mann Whitney, p&lt;0.05). 1 additional woman had a rise in hemoglobin of &gt; 1 gm/dl while on AI therapy which decreased back to baseline when switched to tamoxifen. In conclusion, although the numbers are small and the data retrospective, these data suggest that AI therapy may be associated with an increase in hemoglobin in a subgroup of women treated with AI therapy for localized breast cancer. Given that AI have not been shown to significantly increase the systemic androgen level, the mechanism for the increase in hemoglobin remains unclear. A well designed, prospective study is needed to determine if AI have an effect on hemoglobin in women being treated for breast cancer.


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