Fractional Urea Clearance Estimates Using Two Anthropometric Formulas in Continuous Peritoneal Dialysis: Sex, Height, and Body Composition Differences

Objective To compare estimates of urea volume (V) and KT/V obtained by the Watson and Hume anthropometric formulas, and to identify the similarities and differences between these estimates. Design Theoretical analysis applying wide variations in the determinants of anthropometric V (age, height, weight) in hypothetical women and men. Analysis of urea kinetic studies performed in patients on continuous peritoneal dialysis (CPD). Setting Four dialysis units in Albuquerque, two in Athens, and two in Thessaloniki. Participants Three hundred and two CPD patients who had 440 urea kinetic studies. Intervention Standard urea clearance was performed by 24-hour collections of urine and drained dialysate followed by blood sampling. V was estimated by both the Watson and Hume formulas. Main Outcome Measures Estimates of V and KT/V were compared separately in women and men by Student's t-test, linear regression, and limits of agreement (mean difference±2 SD). The agreement of the KT/V estimates was also tested by the kappa ratio using a value of 1.70 weekly as the lowest acceptable KT/V. Results The theoretical analysis indicated important disagreement only in extreme variations from the ordinary in height and, to a lesser extent, weight. Differences due to height variation were pronounced only in hypothetical women. CPD patient findings were as follows: in women, Watson V and weekly KT/V were 30.4±4.4 L and 2.10±0.61, respectively. Corresponding Hume estimates were 30.3±5.4 L and 2.12±0.66, respectively. Corresponding estimates for men were 40.5±5.7 L and 1.92±0.57 (Watson) plus 41.4±5.6 L and 1.88±0.57 (Hume), respectively. By linear regression, KT/VHume = -0.083 + 1.052 (KT/Vw8tson), r = 0.961 (women); and KT/VHume = -0.026 + 0.992 (KT/Vwatson), r = 0.985 (men). Limits of agreement were -1.41 L and 2.10 L for V, and -0.15 and 0.14 weekly for KT/V. In 94.3% of the cases, KT/Vw8tson and KT/VHume agreed (both >1.70 or both <1.70 weekly). Kappa ratio was 0.875 (excellent agreement). The concordant and discordant groups differed in height and degree of obesity, in agreement with the theoretical analysis. Conclusion The Watson and Hume formulas provide similar estimates of V and KT/V in CPD patients. Differences may be noted only if women's height or, to a lesser extent, both sexes’ weight is at a great variance with the ordinary values.

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Paricalcitol and Peritoneal Protein Loss in Peritoneal Dialysis: A Double-Center Study

Blood Purification ◽

10.1159/000488637 ◽

2018 ◽

Vol 46 (2) ◽

pp. 103-110 ◽

Cited By ~ 2

Author(s):

Teresa Jerónimo ◽

Anabela Malho Guedes ◽

Gloria del Peso ◽

Ana Paula Silva ◽

Rafael Selgas ◽

...

Keyword(s):

Cardiovascular Disease ◽

Multivariate Analysis ◽

Peritoneal Dialysis ◽

Pearson Correlation ◽

Pearson Correlation Coefficient ◽

Protein Loss ◽

Student’S T ◽

The Relationship ◽

Center Study ◽

Student’S T Test

Background/Aims: Peritoneal protein loss (PPL) is associated with cardiovascular disease and mortality in peritoneal dialysis (PD). Controversial results have been published about the effect of paricalcitol in PPL among PD patients. This study intends to analyze the relationship between paricalcitol and PPL in PD. Methods: In a retrospective study, prevalent PD patients were divided into 2 groups: “with paricalcitol” and “without paricalcitol”. X2-test, Student’s t test, Pearson correlation coefficient and Logistic Regression analysis were applied. Results: Eighty-two patients were included. PPL was lower among patients medicated with paricalcitol (5.17 ± 1.71 vs. 6.79 ± 2.10 g/24 h, p = 0.0001). In multivariate analysis, paricalcitol and dialysate/plasma ratio of creatinine (D/P creatinine) were independently related to PPL (OR 4.270 [1.437–12.684], p = 0.009 and OR 0.205 [0.064–0.659], p = 0.008, respectively), adjusted for diabetes. Conclusion: Paricalcitol and D/P creatinine were independently related to PPL. Paricalcitol may have an effect on PPL in PD patients

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Haptoglobin study in myasthenia gravis

Arquivos de Neuro-Psiquiatria ◽

10.1590/s0004-282x2008000200017 ◽

2008 ◽

Vol 66 (2a) ◽

pp. 229-233 ◽

Cited By ~ 1

Author(s):

Leonardo H. Mendonça Oliveira ◽

Marcondes C. França Jr ◽

Anamarli Nucci ◽

Denise Madureira de Oliveira ◽

Elza Myiuki Kimura ◽

...

Keyword(s):

Linear Regression ◽

Myasthenia Gravis ◽

Disease Severity ◽

Disease Status ◽

Cross Sectional Study ◽

Sectional Study ◽

Functional Scale ◽

Cross Sectional ◽

Student’S T ◽

Student’S T Test

OBJECTIVE: A cross-sectional study of haptoglobin (Hp) in myasthenia gravis (MG) was designed, with the objective to identify its values and correlate them with different disease status. METHOD: 46 patients were enrolled in the study, all having disease severity established according to the quantitative myasthenia gravis strength scores (QMGSS). Based on the functional scale determined by Myasthenia Gravis Foundation of America (MGFA) recommendations, patients were classified as having: complete stable remission (CSR; n=10); minimal manifestations-0 (MM0; n=6), minimal manifestations-1 (MM1; n=4); pharmacological remission (PR; n=6). Two other groups participated: thymomatous patients (T; n=10) and patients without imunosuppression or thymectomy, until the assessment for Hp (WIT; n=10). Hp dosage was done by immunonephelometry, blindly to clinical data. Student's t-test, Anova test and linear regression were employed for statistical analyses. RESULTS: Statistically significant differences occurred between CSR+MM0xWIT groups (86.62x157.57, p<0.001) and PR+MM1xWIT groups (73.93x157.57, p<0.001). Linear regression showed correlation between Hp levels and QMGSS (r=0.759, p<0.001). CONCLUSION: Our results suggest that Hp may be useful in clinical practice as a disease severity marker in MG.

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Anatomic and histological characteristics of vagina reconstructed by McIndoe method

Vojnosanitetski pregled ◽

10.2298/vsp0902107k ◽

2009 ◽

Vol 66 (2) ◽

pp. 107-112

Author(s):

Jefta Kozarski ◽

Svetlana Vesanovic ◽

Zoran Bogdanovic

Keyword(s):

Skin Graft ◽

Split Skin Graft ◽

A Value ◽

Gynecological Examination ◽

History Of ◽

Histological Characteristics ◽

Ancient Times ◽

Student’S T ◽

Split Skin ◽

Student’S T Test

Background/Aim. Congenital absence of vagina is known from ancient times of Greek. According to the literature data, incidence is 1/4 000 to 1/20 000. Treatment of this anomaly includes non-operative and operative procedures. McIndoe procedure uses split skin graft by Thiersch. The aim of this study was to establish anatomic and histological characteristics of vagina reconstructed by McIndoe method in Mayer K?ster-Rockitansky Hauser (MKRH) syndrome and compare them with normal vagina. Methods. The study included 21 patients of 18 and more years with congenital anomaly known as aplasio vaginae within the Mayer K?ster-Rockitansky Hauser syndrome. The patients were operated on by the plastic surgeon using the McIndoe method. The study was a retrospective review of the data from the history of the disease, objective and gynecological examination and cytological analysis of native preparations of vaginal stain (Papanicolau). Comparatively, 21 females of 18 and more years with normal vaginas were also studied. All the subjects were divided into the groups R (reconstructed) and C (control) and the subgroups according to age up to 30 years (1 R, 1C), from 30 to 50 (2R, 2C), and over 50 (3R, 3C). Statistical data processing was performed by using the Student's t-test and Mann-Writney U-test. A value of p < 0.05 was considered statistically significant. Results. The results show that there are differences in the depth and the wideness of reconstructed vagina, but the obtained values are still in the range of normal ones. Cytological differences between a reconstructed and the normal vagina were found. Conclusion. A reconstructed vagina is smaller than the normal one regarding depth and width, but within the range of normal values. A split skin graft used in the reconstruction, keeps its own cytological, i.e. histological and, so, biological characteristics.

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Relationships between fish length, otolith size and otolith weight in Sperata aor (Bagridae) and Labeo bata (Cyprinidae) from the Ganga River, India

Zoology and Ecology ◽

10.35513/21658005.2019.2.3 ◽

2019 ◽

Vol 29 (2) ◽

pp. 93-98

Author(s):

Aafaq Nazir ◽

M. Afzal Khan

Keyword(s):

Linear Regression ◽

Fish Species ◽

Strong Relationship ◽

Trophic Relationships ◽

Fish Length ◽

Labeo Bata ◽

River Ganga ◽

Student’S T ◽

Otolith Size ◽

Student’S T Test

The present study was conducted to investigate the relationships between fish length, otolith size and otolith weight. A total of 180 Sperata aor and 171 Labeo bata specimens were collected monthly during January 2016 to March 2017 from the River Ganga at the Narora site. Student’s t-test showed no significant differences in the size of right and left otoliths in the selected fish species, therefore, a single linear regression based on the left otolith was carried out. Fish length was plotted against otolith weight, otolith length and otolith height. Moreover, otolith length was plotted against otolith weight and otolith height. The linear regression model was found to fit the data well for fish length to otolith size in both selected fish species. A strong relationship between otolith length and weight was found in both species (r2 > 0.8). Furthermore, the study revealed that fish length is potentially related to otolith size and a strong relationship between fish length and otolith size exists in S. aor (mean r2 = 0.89) as compared to L. bata (mean r2 = 0.70). Such relationships should be determined for the fish species that are ecologically and socio-economically important in order to understand their trophic relationships, population dynamics and yield estimates.

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The Effect of Different Shades, Voltages and Increment Thickness on the Polymerization Depth of a Microhybrid Composite

International Journal of Prosthodontics and Restorative Dentistry ◽

10.5005/jp-journals-10019-1048 ◽

2012 ◽

Vol 2 (2) ◽

pp. 52-56

Author(s):

Farhan Raza Khan ◽

Muhammad Hasan ◽

Syed Iqbal Azam

Keyword(s):

Composite Material ◽

Linear Regression ◽

Developing World ◽

Dental Composite ◽

P Value ◽

Depth Of Cure ◽

Variable Voltage ◽

The Mean ◽

Student’S T ◽

Student’S T Test

ABSTRACT Aim Electric fluctuations in the developing world are common and may affect dental composite curing. We determined the effect of variable voltage and increasing thickness of different shades of composite on its depth-of-cure. Materials and methods ISO scrapping method was used on 14 commonly used shades of Esthet-X HD composites. Student's t-test and ANOVA were applied to compare the mean depth-of-cure and a linear regression model was developed using variables voltage (180 V and 220 V), material thickness (2, 4 and 6 mm) and shades (n = 14). Results The mean curing depth of samples was significantly reduced at 180 volts compared to 220 volts (p-value <0.002). At thickness of 2 mm, all samples were fully cured but when it was raised to 4 mm, the depth-of-cure reduced to 1.86 mm ± 0.06; while at 6 mm thickness, it reached to 1.96 mm ± 0.06 (p-value < 0.001). Conclusion Around 82% variation in the depth-of-cure is explained by voltage, thickness and shade of composite material (p-value <0.001). Clinical significance Electric fluctuations are prevalent in the developing world and thus poor voltage flow is responsible for dental composite's inadequate polymerization. How to cite this article Khan FR, Hasan M, Azam SI. The Effect of Different Shades, Voltages and Increment Thickness on the Polymerization Depth of a Microhybrid Composite. Int J Prosthodont Restor Dent 2012;2(2):52-56.

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Estimating Urea Clearance in Patients on Continuous Ambulatory Peritoneal Dialysis: A Multivariate Analysis

The International Journal of Artificial Organs ◽

10.1177/039139889802100909 ◽

1998 ◽

Vol 21 (9) ◽

pp. 515-520 ◽

Cited By ~ 2

Author(s):

G.H. Murata ◽

A.H. Tzamaloukas ◽

S. Voudiklari ◽

A. Dimitriadis ◽

E. V. Balaskas ◽

...

Keyword(s):

Peritoneal Dialysis ◽

Linear Regression ◽

Multiple Linear Regression ◽

Continuous Ambulatory Peritoneal Dialysis ◽

Linear Models ◽

Urine Volume ◽

Residual Renal Function ◽

Urea Clearance ◽

Clearance Studies ◽

Multivariate Linear Models

The purpose of this study was to determine if Kt/V urea in continuous ambulatory peritoneal dialysis (CAPD) could be estimated by a multivariate model based upon simple clinical observations. The study included 439 clearance studies in 301 CAPD patients followed in 8 dialysis centers. Weekly urea clearance, 24 h urine volume and 24 h drain volume were normalized to body water by the formulae of Watson (Kt/V, UV/V, and DV/V respectively). Adequate dialysis was defined as Kt/V ≥2.0 weekly. Subjects at 2 units were used to derive the models, while others were used for model validation. Stepwise multiple linear regression was performed on the derivation set (DS) to identify the clinical variables that correlated with Kt/V. The model was then used to estimate Kt/V for the validation set (VS). In the DS, 110 clearance studies were performed in subjects with residual renal function. Multiple linear regression showed that weekly Kt/V was defined by the expression: Kt/V = 1.48 + 24.1 (UV/V) + 2.92(DV/V) - 0.049 (serum creatinine) (r=0.750, p<0.001). In 204 VS studies, the correlation between estimated and measured Kt/V was 0.633. There were marked differences in the proportion of adequately dialyzed patients when Kt/V estimated from the formula shown was <2.0, between 2.0 and 2.3, and >2.3 weekly (7.9%, 54.7% and 79.7%, respectively; p<0.001). In the 33 studies done in DS anuric patients, regression analysis showed the following: Kt/V = 0.46 + 2.59 (DV/V) + 0.009(age) (r=0.562; p = 0.003). In 92 VS studies in anuric subjects, there was strong correlation between estimated and measured Kt/V (r=0.740). Again, there were marked differences in the frequency of adequate dialysis in anuric patients with estimated Kt/V <2.0, between 2.0 and 2.3, and >2.3 weekly (8.1%, 68.8%, and 100%, respectively; p<0.001). The risk of low Kt/V can be estimated by multivariate linear models requiring only simple clinical measurements.

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A machine learning-based diagnostic model associated with knee osteoarthritis severity

Scientific Reports ◽

10.1038/s41598-020-72941-4 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Soon Bin Kwon ◽

Yunseo Ku ◽

Hy uk-soo Han ◽

Myung Chul Lee ◽

Hee Chan Kim ◽

...

Keyword(s):

Machine Learning ◽

Linear Regression ◽

Regression Models ◽

Learning Algorithm ◽

T Test ◽

Machine Learning Algorithm ◽

Linear Regression Models ◽

Estimation Model ◽

Student’S T ◽

Student’S T Test

Abstract Knee osteoarthritis (KOA) is characterized by pain and decreased gait function. We aimed to find KOA-related gait features based on patient reported outcome measures (PROMs) and develop regression models using machine learning algorithms to estimate KOA severity. The study included 375 volunteers with variable KOA grades. The severity of KOA was determined using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). WOMAC scores were used to classify disease severity into three groups. A total of 1087 features were extracted from the gait data. An ANOVA and student’s t-test were performed and only features that were significant were selected for inclusion in the machine learning algorithm. Three WOMAC subscales (physical function, pain and stiffness) were further divided into three classes. An ANOVA was performed to determine which selected features were significantly related to the subscales. Both linear regression models and a random forest regression was used to estimate patient the WOMAC scores. Forty-three features were selected based on ANOVA and student’s t-test results. The following number of features were selected from each joint: 12 from hip, 1 feature from pelvic, 17 features from knee, 9 features from ankle, 1 feature from foot, and 3 features from spatiotemporal parameters. A significance level of < 0.0001 and < 0.00003 was set for the ANOVA and t-test, respectively. The physical function, pain, and stiffness subscales were related to 41, 10, and 16 features, respectively. Linear regression models showed a correlation of 0.723 and the machine learning algorithm showed a correlation of 0.741. The severity of KOA was predicted by gait analysis features, which were incorporated to develop an objective estimation model for KOA severity. The identified features may serve as a tool to guide rehabilitation and progress assessments. In addition, the estimation model presented here suggests an approach for clinical application of gait analysis data for KOA evaluation.

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TL 18091 - Risk in the sinus tarsi approach

Scientific Journal of the Foot & Ankle ◽

10.30795/scijfootankle.2019.v13.1040 ◽

2019 ◽

Vol 13 (Supl 1) ◽

pp. 75S

Author(s):

Lourenço Galizia Heitzmann ◽

Wellington Farias Molina ◽

Guilherme Bottino Martins ◽

Luiz Sergio Martins Pimenta ◽

Fernando Salgueiro Alvo ◽

...

Keyword(s):

Sural Nerve ◽

Lateral Malleolus ◽

Lower Limbs ◽

Complication Rates ◽

Calcaneal Tendon ◽

Surgical Incision ◽

A Value ◽

Sinus Tarsi Approach ◽

Student’S T ◽

Student’S T Test

Objetivo: To evaluate the topographic and morphometric aspects of the sural nerve in cadavers as well as its relationship with the modified Palmer approach. Methods: Thirty lower limbs of fifteen fresh cadavers were used for dissection of the sural nerve, and 5 measurements were performed using the lateral malleolus and the calcaneal tendon as the repair point. The paired student's T-test was used to compare the averages of the measurements between the sides of the same cadaver. A value of p < 0.05 was considered significant for all analyses. Results: On average, the sural nerve issued its first branch 40.40 mm above the lateral malleolus, situated on average 13.84 mm posterior to the tip of the lateral malleolus and on average 23.76 mm inferior to the point of the lateral malleolus. Conclusion: The modified Palmer’s approach was shown to be promising, since it demonstrated lower postoperative complication rates, especially when compared with the extended lateral pathway. The results obtained will aid during the surgical incision, adding safety to the procedure by avoiding injury of branches of the sural nerve.

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An RSSI-Based Low-Power Vehicle-Approach Detection Technique to Alert a Pedestrian

Sensors ◽

10.3390/s20010118 ◽

2019 ◽

Vol 20 (1) ◽

pp. 118

Author(s):

Yoshito Watanabe ◽

Yozo Shoji

Keyword(s):

Linear Regression ◽

Error Rate ◽

Traffic Accidents ◽

Neighbor Discovery ◽

Detection Error ◽

Received Signal Strength Indicator ◽

Moving Vehicle ◽

Passive Method ◽

Student’S T ◽

Student’S T Test

Information about an approaching vehicle is helpful for pedestrians to avoid traffic accidents while most of the past studies related to collision avoidance systems have focused on alerting drivers and controlling vehicles. This paper proposes a technique to detect an approaching vehicle aiming at alerting a pedestrian by observing the variation of the received signal strength indicator (RSSI) of the repeatedly radiated beacons from a vehicle, called the alert beacons. A linear regression algorithm is first applied to RSSI samples. The decision about whether a vehicle is approaching or not is made by the Student’s t-test for the linear regression coefficient. A passive method, where the pedestrian’s device behaves only as a receiver, is first described. The neighbor-discovery-based (ND-based) method, in which the pedestrian’s device repeatedly broadcasts advertising beacons and the moving vehicle in the vicinity returns the alert beacon when it receives the advertising beacon, is then proposed to improve the detection performance as well as reduce the device’s energy consumption. The theoretical detection error rate under Rayleigh fading is derived. It is revealed that the proposed ND-based method achieves a lower detection error rate when compared with the passive method under the same delay.

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