Scaled test statistics and robust standard errors for non-normal data in covariance structure analysis: a Monte Carlo study.

PubMed

Chou, C P; Bentler, P M; Satorra, A

1991-11-01

Research studying robustness of maximum likelihood (ML) statistics in covariance structure analysis has concluded that test statistics and standard errors are biased under severe non-normality. An estimation procedure known as asymptotic distribution free (ADF), making no distributional assumption, has been suggested to avoid these biases. Corrections to the normal theory statistics to yield more adequate performance have also been proposed. This study compares the performance of a scaled test statistic and robust standard errors for two models under several non-normal conditions and also compares these with the results from ML and ADF methods. Both ML and ADF test statistics performed rather well in one model and considerably worse in the other. In general, the scaled test statistic seemed to behave better than the ML test statistic and the ADF statistic performed the worst. The robust and ADF standard errors yielded more appropriate estimates of sampling variability than the ML standard errors, which were usually downward biased, in both models under most of the non-normal conditions. ML test statistics and standard errors were found to be quite robust to the violation of the normality assumption when data had either symmetric and platykurtic distributions, or non-symmetric and zero kurtotic distributions.

Accuracy of Blood Loss Measurement during Cesarean Delivery.

PubMed

Doctorvaladan, Sahar V; Jelks, Andrea T; Hsieh, Eric W; Thurer, Robert L; Zakowski, Mark I; Lagrew, David C

2017-04-01

Objective  This study aims to compare the accuracy of visual, quantitative gravimetric, and colorimetric methods used to determine blood loss during cesarean delivery procedures employing a hemoglobin extraction assay as the reference standard. Study Design  In 50 patients having cesarean deliveries blood loss determined by assays of hemoglobin content on surgical sponges and in suction canisters was compared with obstetricians' visual estimates, a quantitative gravimetric method, and the blood loss determined by a novel colorimetric system. Agreement between the reference assay and other measures was evaluated by the Bland-Altman method. Results  Compared with the blood loss measured by the reference assay (470 ± 296 mL), the colorimetric system (572 ± 334 mL) was more accurate than either visual estimation (928 ± 261 mL) or gravimetric measurement (822 ± 489 mL). The correlation between the assay method and the colorimetric system was more predictive (standardized coefficient = 0.951, adjusted R 2  = 0.902) than either visual estimation (standardized coefficient = 0.700, adjusted R 2  = 00.479) or the gravimetric determination (standardized coefficient = 0.564, adjusted R 2  = 0.304). Conclusion  During cesarean delivery, measuring blood loss using colorimetric image analysis is superior to visual estimation and a gravimetric method. Implementation of colorimetric analysis may enhance the ability of management protocols to improve clinical outcomes.

Accuracy of Blood Loss Measurement during Cesarean Delivery

PubMed Central

Doctorvaladan, Sahar V.; Jelks, Andrea T.; Hsieh, Eric W.; Thurer, Robert L.; Zakowski, Mark I.; Lagrew, David C.

2017-01-01

Objective This study aims to compare the accuracy of visual, quantitative gravimetric, and colorimetric methods used to determine blood loss during cesarean delivery procedures employing a hemoglobin extraction assay as the reference standard. Study Design In 50 patients having cesarean deliveries blood loss determined by assays of hemoglobin content on surgical sponges and in suction canisters was compared with obstetricians' visual estimates, a quantitative gravimetric method, and the blood loss determined by a novel colorimetric system. Agreement between the reference assay and other measures was evaluated by the Bland–Altman method. Results Compared with the blood loss measured by the reference assay (470 ± 296 mL), the colorimetric system (572 ± 334 mL) was more accurate than either visual estimation (928 ± 261 mL) or gravimetric measurement (822 ± 489 mL). The correlation between the assay method and the colorimetric system was more predictive (standardized coefficient = 0.951, adjusted R2 = 0.902) than either visual estimation (standardized coefficient = 0.700, adjusted R2 = 00.479) or the gravimetric determination (standardized coefficient = 0.564, adjusted R2 = 0.304). Conclusion During cesarean delivery, measuring blood loss using colorimetric image analysis is superior to visual estimation and a gravimetric method. Implementation of colorimetric analysis may enhance the ability of management protocols to improve clinical outcomes. PMID:28497007

Free kick instead of cross-validation in maximum-likelihood refinement of macromolecular crystal structures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pražnikar, Jure; University of Primorska,; Turk, Dušan, E-mail: dusan.turk@ijs.si

2014-12-01

The maximum-likelihood free-kick target, which calculates model error estimates from the work set and a randomly displaced model, proved superior in the accuracy and consistency of refinement of crystal structures compared with the maximum-likelihood cross-validation target, which calculates error estimates from the test set and the unperturbed model. The refinement of a molecular model is a computational procedure by which the atomic model is fitted to the diffraction data. The commonly used target in the refinement of macromolecular structures is the maximum-likelihood (ML) function, which relies on the assessment of model errors. The current ML functions rely on cross-validation. Theymore » utilize phase-error estimates that are calculated from a small fraction of diffraction data, called the test set, that are not used to fit the model. An approach has been developed that uses the work set to calculate the phase-error estimates in the ML refinement from simulating the model errors via the random displacement of atomic coordinates. It is called ML free-kick refinement as it uses the ML formulation of the target function and is based on the idea of freeing the model from the model bias imposed by the chemical energy restraints used in refinement. This approach for the calculation of error estimates is superior to the cross-validation approach: it reduces the phase error and increases the accuracy of molecular models, is more robust, provides clearer maps and may use a smaller portion of data for the test set for the calculation of R{sub free} or may leave it out completely.« less

A semi-automatic method for left ventricle volume estimate: an in vivo validation study

NASA Technical Reports Server (NTRS)

Corsi, C.; Lamberti, C.; Sarti, A.; Saracino, G.; Shiota, T.; Thomas, J. D.

2001-01-01

This study aims to the validation of the left ventricular (LV) volume estimates obtained by processing volumetric data utilizing a segmentation model based on level set technique. The validation has been performed by comparing real-time volumetric echo data (RT3DE) and magnetic resonance (MRI) data. A validation protocol has been defined. The validation protocol was applied to twenty-four estimates (range 61-467 ml) obtained from normal and pathologic subjects, which underwent both RT3DE and MRI. A statistical analysis was performed on each estimate and on clinical parameters as stroke volume (SV) and ejection fraction (EF). Assuming MRI estimates (x) as a reference, an excellent correlation was found with volume measured by utilizing the segmentation procedure (y) (y=0.89x + 13.78, r=0.98). The mean error on SV was 8 ml and the mean error on EF was 2%. This study demonstrated that the segmentation technique is reliably applicable on human hearts in clinical practice.

Local Influence and Robust Procedures for Mediation Analysis

ERIC Educational Resources Information Center

Zu, Jiyun; Yuan, Ke-Hai

2010-01-01

Existing studies of mediation models have been limited to normal-theory maximum likelihood (ML). Because real data in the social and behavioral sciences are seldom normally distributed and often contain outliers, classical methods generally lead to inefficient or biased parameter estimates. Consequently, the conclusions from a mediation analysis…

Highly controlled vascular syringes for pericardiocentesis.

PubMed

Ricciardi, Mark; Roldan, Carlos; Sibbitt, Randy; Sibbitt, Wilmer; Michael, Adrian; Palmer, Dennis

2010-12-01

The present study determined the utility and needle control characteristics of highly controlled vascular syringes for image-guided pericardiocentesis. Vascular syringes have been integrated into invasive cardiovascular procedures with improved patient safety, but to date have not been used in pericardiocentesis. To address this issue, we determined the method of use of vascular syringes for pericardiocentesis. A vascular syringe with reciprocating plungers, the reciprocating procedure device (RPD syringe), replaced the corresponding 10 ml and 20 ml conventional syringes in a standard pericardiocentesis tray. The vascular syringe is controlled with one hand, and can either aspirate or inject by pushing the corresponding aspiration or injection plunger. Four hundred and thirty seven subjects underwent vascular syringe procedures. The linear displacement method was used to precisely measure control of the needle tip in millimeters (mm) in vascular syringes compared to conventional syringes in 20 individual operators. Relative to the corresponding 10 ml and 20 ml conventional syringes, vascular syringes significantly reduced unintended forward penetration of the needle tip by 44% (7.0 ± 4.3 mm; p < 0.0001) and 53% (10.1 ± 5.5 mm; p < 0.0001), respectively, and reduced unintended retraction of the needle by 56% (2.7 ± 2.2 mm; p < 0.001) and 60% (3.5 ± 2.5 mm; p < 0.001), respectively. During pericardiocentesis, the mechanical syringe permitted facile one-handed aspiration and maintained the operator's ability to clear the needle. In the 437 vascular syringe procedures, there were no complications, with an estimated cost savings of $10-65 per procedure. Vascular syringes improve needle control in pericardiocentesis, promote patient safety and permit one-handed aspiration and injection.

[Preliminary clinical experience of single incision laparoscopic colorectal surgery].

PubMed

Wu, S D; Han, J Y

2016-06-01

Objective: To discuss the preliminary experience of single incision laparoscopic colorectal surgery. Methods: The clinical data and surgical outcomes of 104 selected patients who underwent single incision laparoscopic colorectal surgery in the 2 nd Department of General Surgery, Shengjing Hospital of China Medical University from January 2010 to September 2015 were retrospectively analyzed. There were 62 male and 42 female patients, aging from 21 to 87 years with a mean of (61±12) years. Eighty-five patients were diagnosed with malignancy while the rest 19 cases were benign diseases. All the procedures were performed by the same surgeon using the rigid laparoscopic instruments. Surgical and oncological outcomes were analyzed in 4 kinds of procedures which are over 5 cases respectively, including low anterior resection, abdominoperineal resection, radical right colon resection and radical sigmoidectomy. Results: Single incision laparoscopic colorectal surgery was performed in 104 selected patients and was successfully managed in 99 cases with a total conversion rate of 4.8%. Radical procedures for malignancy in cases with the number of patients more than 5 were performed for 74 cases. For low anterior resection, 35 cases with an average surgical time of (191±57) minutes, average estimated blood loss of (117±72) ml and average number of harvested lymph nodes of 14.6±1.1. For abdominoperineal resection, 9 cases with an average surgical time of (226±54) minutes, average estimated blood loss of (194±95) ml and average number of harvested lymph nodes of 14.1±1.5. For radical right colon resection, 16 cases with an average surgical time of (222±62) minutes, average estimated blood loss of (142±68) ml and average number of harvested lymph nodes of 15.4±2.4. For radical sigmoidectomy, 14 cases with an average surgical time of (159±32) minutes, average estimated blood loss of (94±33) ml and average number of harvested lymph nodes of 13.9±1.5. The overall intraoperative complication rate was 2.7% (2 cases) and postoperative complication rate was 8.1% (6 cases) in these 74 cases. Conclusion: Single incision laparoscopic colorectal surgery is safe and feasible with acceptable surgical outcomes and cosmetic benefits in the hands of skilled laparoscopic surgeon in well-selected patients.

3D Volumetry and its Correlation Between Postoperative Gastric Volume and Excess Weight Loss After Sleeve Gastrectomy.

PubMed

Hanssen, Andrés; Plotnikov, Sergio; Acosta, Geylor; Nuñez, José Tomas; Haddad, José; Rodriguez, Carmen; Petrucci, Claudia; Hanssen, Diego; Hanssen, Rafael

2018-03-01

The volume of the postoperative gastric remnant is a key factor in excess weight loss (EWL) after sleeve gastrectomy (SG). Traditional methods to estimate gastric volume (GV) after bariatric procedures are often inaccurate; usually conventional biplanar contrast studies are used. Thirty patients who underwent SG were followed prospectively and evaluated at 6 months after the surgical procedure, performing 3D CT reconstruction and gastric volumetry, to establish its relationship with EWL. The gastric remnant was distended with effervescent sodium bicarbonate given orally. Helical CT images were acquired and reconstructed; GV was estimated with the software of the CT device. The relationship between GV and EWL was analyzed. The study allowed estimating the GV in all patients. A dispersion diagram showed an inverse relationship between GV and %EWL. 55.5% of patients with GV ≤ 100 ml had %EWL 25-75% and 38.8% had an %EWL above 75% and patients with GV ≥ 100 ml had an %EWL under 25% (50% of patients) or between 25 and 75% (50% of this group). The Pearson's correlation coefficient was R = 6.62, with bilateral significance (p ≤ .01). The Chi-square result correlating GV and EWL showed a significance of .005 (p ≤ .01). The 3D reconstructions showed accurately the shape and anatomic details of the gastric remnant. 3D volumetry CT scans accurately estimate GV after SG. A significant relationship between GV and EWL 6 months after SG was established, seeming that GV ≥ 100 ml at 6 months of SG is associated with poor EWL.

Continuous stroke volume estimation from aortic pressure using zero dimensional cardiovascular model: proof of concept study from porcine experiments.

PubMed

Kamoi, Shun; Pretty, Christopher; Docherty, Paul; Squire, Dougie; Revie, James; Chiew, Yeong Shiong; Desaive, Thomas; Shaw, Geoffrey M; Chase, J Geoffrey

2014-01-01

Accurate, continuous, left ventricular stroke volume (SV) measurements can convey large amounts of information about patient hemodynamic status and response to therapy. However, direct measurements are highly invasive in clinical practice, and current procedures for estimating SV require specialized devices and significant approximation. This study investigates the accuracy of a three element Windkessel model combined with an aortic pressure waveform to estimate SV. Aortic pressure is separated into two components capturing; 1) resistance and compliance, 2) characteristic impedance. This separation provides model-element relationships enabling SV to be estimated while requiring only one of the three element values to be known or estimated. Beat-to-beat SV estimation was performed using population-representative optimal values for each model element. This method was validated using measured SV data from porcine experiments (N = 3 female Pietrain pigs, 29-37 kg) in which both ventricular volume and aortic pressure waveforms were measured simultaneously. The median difference between measured SV from left ventricle (LV) output and estimated SV was 0.6 ml with a 90% range (5th-95th percentile) -12.4 ml-14.3 ml. During periods when changes in SV were induced, cross correlations in between estimated and measured SV were above R = 0.65 for all cases. The method presented demonstrates that the magnitude and trends of SV can be accurately estimated from pressure waveforms alone, without the need for identification of complex physiological metrics where strength of correlations may vary significantly from patient to patient.

Simple, sensitive, selective and validated spectrophotometric methods for the estimation of a biomarker trigonelline from polyherbal gels

NASA Astrophysics Data System (ADS)

Chopra, Shruti; Motwani, Sanjay K.; Ahmad, Farhan J.; Khar, Roop K.

2007-11-01

Simple, accurate, reproducible, selective, sensitive and cost effective UV-spectrophotometric methods were developed and validated for the estimation of trigonelline in bulk and pharmaceutical formulations. Trigonelline was estimated at 265 nm in deionised water and at 264 nm in phosphate buffer (pH 4.5). Beer's law was obeyed in the concentration ranges of 1-20 μg mL -1 ( r2 = 0.9999) in deionised water and 1-24 μg mL -1 ( r2 = 0.9999) in the phosphate buffer medium. The apparent molar absorptivity and Sandell's sensitivity coefficient were found to be 4.04 × 10 3 L mol -1 cm -1 and 0.0422 μg cm -2/0.001A in deionised water; and 3.05 × 10 3 L mol -1 cm -1 and 0.0567 μg cm -2/0.001A in phosphate buffer media, respectively. These methods were tested and validated for various parameters according to ICH guidelines. The detection and quantitation limits were found to be 0.12 and 0.37 μg mL -1 in deionised water and 0.13 and 0.40 μg mL -1 in phosphate buffer medium, respectively. The proposed methods were successfully applied for the determination of trigonelline in pharmaceutical formulations (vaginal tablets and bioadhesive vaginal gels). The results demonstrated that the procedure is accurate, precise, specific and reproducible (percent relative standard deviation <2%), while being simple and less time consuming and hence can be suitably applied for the estimation of trigonelline in different dosage forms and dissolution studies.

Free uroflowmetry versus "Do-It-Yourself" uroflowmetry in the assessment of patients with lower urinary tract symptoms.

PubMed

Mombelli, Gabriella; Picozzi, Stefano; Messina, Giovanni; Truffelli, Dario; Marenghi, Carlo; Maffi, Gabriele; Carmignani, Luca

2014-10-01

We investigated the possibility that patients could carry out a urine flow assessment at home by themselves, in comfort, without expense and without the use of equipment. We compared this strategy of "Do-It-Yourself" (DIY) uroflowmetry with traditional, hospital uroflowmetry. One hundred and twenty patients were enrolled. The patients underwent conventional, free uroflowmetry in hospital. Subsequently, the patients were asked to carry out the following procedure at home: urinate into a graduated container to quantify the total voided volume and determine the flow time by measuring the duration of miction with a stopwatch or simply with the second hand of a clock. This procedure had to be performed three times without preparation. Hundred patients completed the study. The mean age of the patients analysed was 64.12 years. Their free uroflowmetry values were as follows: the mean voiding time was 44.28 s, the mean voided volume was 290.92 ml, the mean Qmax was 15.17 ml/s, the mean Qmean was 7.87 ml/s, and the mean post-void residual volume was 78.44 ml. The mean Qmean measured by the "DIY-uroflowmetry" was 8.33 ml/s, which was not statistically significantly different (P = 0.12). Assuming that pathological hospital uroflowmetry values are equivalent to a DIY-Qmean ≤10 ml/s and that normal hospital values are equivalent to a DIY-Qmean >10 ml/s, the concordance was 100 %. Our proposed DIY evaluation of urine flow, together with the International Prostatic Symptom Score (IPSS), provides a good estimate of the results of free uroflowmetry, enabling unnecessary hospital investigations to be avoided.

Fetomaternal hemorrhage during external cephalic version.

PubMed

Boucher, Marc; Marquette, Gerald P; Varin, Jocelyne; Champagne, Josette; Bujold, Emmanuel

2008-07-01

To estimate the frequency and volume of fetomaternal hemorrhage during external cephalic version for term breech singleton fetuses and to identify risk factors involved with this complication. A prospective observational study was performed including all patients undergoing a trial of external cephalic version for a breech presentation of at least 36 weeks of gestation between 1987 and 2001 in our center. A search for fetal erythrocytes using the standard Kleihauer-Betke test was obtained before and after each external cephalic version. The frequency and volume of fetomaternal hemorrhage were calculated. Putative risk factors for fetomaternal hemorrhage were evaluated by chi(2) test and Mann-Whitney U test. A Kleihauer-Betke test result was available before and after 1,311 trials of external cephalic version. The Kleihauer-Betke test was positive in 67 (5.1%) before the procedure. Of the 1,244 women with a negative Kleihauer-Betke test before external cephalic version, 30 (2.4%) had a positive Kleihauer-Betke test after the procedure. Ten (0.8%) had an estimated fetomaternal hemorrhage greater than 1 mL, and one (0.08%) had an estimated fetomaternal hemorrhage greater than 30 mL. The risk of fetomaternal hemorrhage was not influenced by parity, gestational age, body mass index, number of attempts at version, placental location, or amniotic fluid index. The risk of detectable fetomaternal hemorrhage during external cephalic version was 2.4%, with fetomaternal hemorrhage more than 30 mL in less than 0.1% of cases. These data suggest that the performance of a Kleihauer-Betke test is unwarranted in uneventful external cephalic version and that in Rh-negative women, no further Rh immune globulin is necessary other than the routine 300-microgram dose at 28 weeks of gestation and postpartum. II.

Estimation and Mapping of Clouds and Rainfall Areas with an Interactive Computer.

DTIC Science & Technology

1982-12-01

test. C . TEST PROCEDURES The following lis1t is the set of procedures for this test of the SPADS Cloud Model. The steps taken were to: 1. Capture...12, 1640-1648. 121 0 APPENDIX4 SPADS CLOUD MlDEL COMPUTER PROGrRArt C CLOY) -IS DRIVER/IMAIN PROGRAIM C T41S PROC.RAM ANALYZES VIS AND IR. TOGETHEI TO...NITH AN INTERACTIVE COMPUTER(U) NAYAL POSTGRADUATE SCHOOL MONTEREY CA C A NELSON DEC 92 UNLSSIFIED F/G 9/2 NUC MENOMONE NONI smhhhhhhhhohh

Definition of an XML markup language for clinical laboratory procedures and comparison with generic XML markup.

PubMed

Saadawi, Gilan M; Harrison, James H

2006-10-01

Clinical laboratory procedure manuals are typically maintained as word processor files and are inefficient to store and search, require substantial effort for review and updating, and integrate poorly with other laboratory information. Electronic document management systems could improve procedure management and utility. As a first step toward building such systems, we have developed a prototype electronic format for laboratory procedures using Extensible Markup Language (XML). Representative laboratory procedures were analyzed to identify document structure and data elements. This information was used to create a markup vocabulary, CLP-ML, expressed as an XML Document Type Definition (DTD). To determine whether this markup provided advantages over generic markup, we compared procedures structured with CLP-ML or with the vocabulary of the Health Level Seven, Inc. (HL7) Clinical Document Architecture (CDA) narrative block. CLP-ML includes 124 XML tags and supports a variety of procedure types across different laboratory sections. When compared with a general-purpose markup vocabulary (CDA narrative block), CLP-ML documents were easier to edit and read, less complex structurally, and simpler to traverse for searching and retrieval. In combination with appropriate software, CLP-ML is designed to support electronic authoring, reviewing, distributing, and searching of clinical laboratory procedures from a central repository, decreasing procedure maintenance effort and increasing the utility of procedure information. A standard electronic procedure format could also allow laboratories and vendors to share procedures and procedure layouts, minimizing duplicative word processor editing. Our results suggest that laboratory-specific markup such as CLP-ML will provide greater benefit for such systems than generic markup.

9 CFR 147.30 - Laboratory procedure recommended for the polymerase chain reaction (PCR) test for Mycoplasma...

Code of Federal Regulations, 2012 CFR

2012-01-01

... for Mycoplasma gallisepticum and M. synoviae. (a) DNA isolation. Isolate DNA from 1 mL of eluate from... supernatant DNA to a nuclease-free tube. Estimate the DNA concentration and purity by spectrophotometric... primer (50 μM), 1 μl Forward primer (50 μM). (2) Perform DNA amplification in a Perkin-Elmer 9600...

9 CFR 147.30 - Laboratory procedure recommended for the polymerase chain reaction (PCR) test for Mycoplasma...

Code of Federal Regulations, 2014 CFR

2014-01-01

... for Mycoplasma gallisepticum and M. synoviae. (a) DNA isolation. Isolate DNA from 1 mL of eluate from... supernatant DNA to a nuclease-free tube. Estimate the DNA concentration and purity by spectrophotometric... primer (50 μM), 1 μl Forward primer (50 μM). (2) Perform DNA amplification in a Perkin-Elmer 9600...

9 CFR 147.30 - Laboratory procedure recommended for the polymerase chain reaction (PCR) test for Mycoplasma...

Code of Federal Regulations, 2013 CFR

2013-01-01

... for Mycoplasma gallisepticum and M. synoviae. (a) DNA isolation. Isolate DNA from 1 mL of eluate from... supernatant DNA to a nuclease-free tube. Estimate the DNA concentration and purity by spectrophotometric... primer (50 μM), 1 μl Forward primer (50 μM). (2) Perform DNA amplification in a Perkin-Elmer 9600...

Foot volume estimates based on a geometric algorithm in comparison to water displacement.

PubMed

Mayrovitz, H N; Sims, N; Litwin, B; Pfister, S

2005-03-01

Assessing lower extremity limb volume and its change during and after lymphedema therapy is important for determining treatment efficacy and documenting outcomes. Although leg volumes may be determined by tape measure and other methods, there is no metric method to routinely assess foot volumes. Exclusion of foot volumes can under- or overestimate therapeutic progress. Our aim was to develop and test a metric measurement procedure and algorithm for practicing therapists to use to estimate foot volumes. The method uses a caliper and ruler to measure foot dimensions at standardized locations and calculates foot volume (VM) by a mathematical algorithm. VM was compared to volumes measured by water displacement (Vw) in 30 subjects (60 feet) using regression analysis and limits of agreement (LOA). Vw and VM (mean +/- sd) were similar 857 +/- 150 ml vs. 859 +/- 154 ml, and were highly correlated VM = 1.00Vw + 1.67 ml, r = 0.965, p < 0.001. The LOA for absolute volume differences and percentages were respectively +/- 79.6 ml and +/- 9.28 %. These results indicate that this metric method can be a useful alternative to water displacement when foot volumes are needed, but the water displacement method is contraindicated, impractical to implement, too time consuming or is not available.

Concurrent orthopedic and neurosurgical procedures in pediatric patients with spinal deformity.

PubMed

Mooney, James F; Glazier, Stephen S; Barfield, William R

2012-11-01

The management of pediatric patients with complex spinal deformity often requires both an orthopedic and a neurosurgical intervention. The reasons for multiple subspecialty involvement include, but are not limited to, the presence of a tethered cord requiring release or a syrinx requiring decompression. It has been common practice to perform these procedures in a staged manner, although there is little evidence in the literature to support separate interventions. We reviewed a series of consecutive patients who underwent spinal deformity correction and a neurosurgical intervention concurrently in an attempt to assess the safety, efficacy, and possible complications associated with such an approach. Eleven patients were reviewed who underwent concurrent orthopedic and neurosurgical procedures. Data were collected for patient demographics, preoperative diagnosis, procedures performed, intraoperative and perioperative complications, as well as any unexpected return to the operating room for any reason. Operative notes and anesthesia records were reviewed to determine estimated blood loss, surgical time, and the use of intraoperative neurological monitoring. Patient diagnoses included myelodysplasia (N=6), congenital scoliosis and/or kyphosis (N=4), and scoliosis associated with Noonan syndrome (N=1). Age at the time of surgery averaged 9 years 2 months (range=14 months to 17 years 2 months). Estimated blood loss averaged 605 ml (range=50-3000 ml). The operative time averaged 313 min (range=157-477 min). There were no intraoperative complications, including incidental dural tears or deterioration in preoperative neurological status. One patient developed a sore associated with postoperative cast immobilization that led to a deep wound infection. It appears that concurrent orthopedic and neurosurgical procedures in pediatric patients with significant spinal deformities can be performed safely and with minimal intraoperative and postoperative complications when utilizing modern surgical and neuromonitoring techniques. Level of evidence=Level IV. © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins.

Pneumoperitoneum pressures during pelvic laparoscopic surgery: a systematic review and meta-analysis.

PubMed

Bogani, Giorgio; Martinelli, Fabio; Ditto, Antonino; Chiappa, Valentina; Lorusso, Domenica; Ghezzi, Fabio; Raspagliesi, Francesco

2015-12-01

Growing evidence suggests that the level of pneumoperitoneal pressure is directly correlated with postoperative pain in patients undergoing laparoscopic procedures. However, only limited evidence is available in the field of gynaecologic surgery. Therefore, this study aimed to compare the effects of low (8mmHg), standard (12mmHg) and high (15mmHg) pneumoperitoneal pressures (LPP

Preoperative Embolization of Venous Malformations Using n-Butyl Cyanoacrylate.

PubMed

Uller, Wibke; El-Sobky, Sherif; Alomari, Ahmad I; Fishman, Steven J; Spencer, Samantha A; Taghinia, Amir H; Chaudry, Gulraiz

2018-05-01

The purpose of this study was to evaluate the safety and efficacy of preoperative percutaneous n-butyl cyanoacrylate (nBCA) embolization of venous malformations in children. Clinical data were retrospectively reviewed in children who underwent embolization using nBCA followed by resection of venous malformations. A total of 17 embolizations were performed in 14 patients (9 females, mean age: 5.5 years; median age: 3 years; range 0.1-16 years). The venous malformations involved the lower extremity and the knee joint (n = 7), the trunk (n = 4), head and neck (n = 2), and hand (n = 1). n-Butyl cyanoacrylate was diluted with iodized oil at a ratio of 1:3 to 1:5. The mean and median volume of nBCA per procedure were 2.1 and 2 mL, respectively (range: 0.5-8 mL). There were no complications associated with the procedures. The mean and median time between final embolization and resection were 3.6 and 2 days, respectively. All children underwent successful resection of the symptomatic lesions. The estimated mean and median blood loss were 75 and 50 mL, respectively (range: 5-350 mL). The postprocedure course was uneventful, the days to discharge ranged between 1 and 6 days (mean 3 days). Initial results suggest that preoperative percutaneous n-butyl cyanoacrylate embolization of venous malformations is safe and effective in children, with the potential for minimizing blood loss and inpatient stay.

ART-ML - a novel XML format for the biological procedures modeling and the representation of blood flow simulation.

PubMed

Karvounis, E C; Tsakanikas, V D; Fotiou, E; Fotiadis, D I

2010-01-01

The paper proposes a novel Extensible Markup Language (XML) based format called ART-ML that aims at supporting the interoperability and the reuse of models of blood flow, mass transport and plaque formation, exported by ARTool. ARTool is a platform for the automatic processing of various image modalities of coronary and carotid arteries. The images and their content are fused to develop morphological models of the arteries in easy to handle 3D representations. The platform incorporates efficient algorithms which are able to perform blood flow simulation. In addition atherosclerotic plaque development is estimated taking into account morphological, flow and genetic factors. ART-ML provides a XML format that enables the representation and management of embedded models within the ARTool platform and the storage and interchange of well-defined information. This approach influences in the model creation, model exchange, model reuse and result evaluation.

Safety and complications of percutaneous kidney biopsies in 715 children and 8573 adults in Norway 1988-2010.

PubMed

Tøndel, Camilla; Vikse, Bjørn Egil; Bostad, Leif; Svarstad, Einar

2012-10-01

Skepticism about performing renal biopsies is often because of uncertainty regarding risk of complications. The aim of this study was to evaluate safety and relevant complications of renal biopsies in pediatric and adult patients in a large national registry study. Kidney biopsies reported in the Norwegian Kidney Biopsy Registry from 1988 to 2010 were included. Risk factors for major complications (blood transfusion and/or surgical or catheter intervention) were analyzed using logistic regression statistics. Of the 9288 biopsies included, 715 were from children, and 8573 were from adults (≥18 years). Median age was 49 years (range=2 weeks to 94 years). Gross hematuria appeared after biopsy in 1.9% of the patients; 0.9% of patients needed blood transfusion, and 0.2% of patients needed surgical intervention/catheterization. The frequencies were 1.9%, 0.9%, and 0.2% in adults and 1.7%, 0.1% and 0.1% in children, respectively; 97.9% of the biopsies were without complications. In unadjusted analyses, risk factors for major complications were age>60 years, estimated GFR<60 ml/min per 1.73 m(2), systolic hypertension, acute renal failure, and smaller clinical center size (<30 biopsies/yr). Adjusted analyses (adjusted for age and/or estimated GFR) showed higher odds ratios (OR) only for smaller clinical center (OR=1.60 [1.02-2.50]) and low estimated GFR (estimated GFR=30-59 ml/min per 1.73 m(2) [OR=4.90 (1.60-14.00)] and estimated GFR<30 ml/min per 1.73 m(2) [OR 15.50 (5.60-43.00)]). Percutaneous renal biopsy is a low-risk procedure in all ages. Reduced estimated GFR and smaller center size are associated with an increased risk of major complications.

Evaluation of Shiryaev-Roberts Procedure for On-line Environmental Radiation Monitoring

NASA Astrophysics Data System (ADS)

Watson, Mara Mae

An on-line radiation monitoring system that simultaneously concentrates and detects radioactivity is needed to detect an accidental leakage from a nuclear waste disposal facility or clandestine nuclear activity. Previous studies have shown that classical control chart methods can be applied to on-line radiation monitoring data to quickly detect these events as they occur; however, Bayesian control chart methods were not included in these studies. This work will evaluate the performance of a Bayesian control chart method, the Shiryaev-Roberts (SR) procedure, compared to classical control chart methods, Shewhart 3-sigma and cumulative sum (CUSUM), for use in on-line radiation monitoring of 99Tc in water using extractive scintillating resin. Measurements were collected by pumping solutions containing 0.1-5 Bq/L of 99Tc, as 99T cO4-, through a flow cell packed with extractive scintillating resin coupled to a Beta-RAM Model 5 HPLC detector. While 99T cO4- accumulated on the resin, simultaneous measurements were acquired in 10-s intervals and then re-binned to 100-s intervals. The Bayesian statistical method, Shiryaev-Roberts procedure, and classical control chart methods, Shewhart 3-sigma and cumulative sum (CUSUM), were applied to the data using statistical algorithms developed in MATLAB RTM. Two SR control charts were constructed using Poisson distributions and Gaussian distributions to estimate the likelihood ratio, and are referred to as Poisson SR and Gaussian SR to indicate the distribution used to calculate the statistic. The Poisson and Gaussian SR methods required as little as 28.9 mL less solution at 5 Bq/L and as much as 170 mL less solution at 0.5 Bq/L to exceed the control limit than the Shewhart 3-sigma method. The Poisson SR method needed as little as 6.20 mL less solution at 5 Bq/L and up to 125 mL less solution at 0.5 Bq/L to exceed the control limit than the CUSUM method. The Gaussian SR and CUSUM method required comparable solution volumes for test solutions containing at least 1.5 Bq/L of 99T c. For activity concentrations less than 1.5 Bq/L, the Gaussian SR method required as much as 40.8 mL less solution at 0.5 Bq/L to exceed the control limit than the CUSUM method. Both SR methods were able to consistently detect test solutions containing 0.1 Bq/L, unlike the Shewhart 3-sigma and CUSUM methods. Although the Poisson SR method required as much as 178 mL less solution to exceed the control limit than the Gaussian SR method, the Gaussian SR false positive of 0% was much lower than the Poisson SR false positive rate of 1.14%. A lower false positive rate made it easier to differentiate between a false positive and an increase in mean count rate caused by activity accumulating on the resin. The SR procedure is thus the ideal tool for low-level on-line radiation monitoring using extractive scintillating resin, because it needed less volume in most cases to detect an upward shift in the mean count rate than the Shewhart 3-sigma and CUSUM methods and consistently detected lower activity concentrations. The desired results for the monitoring scheme, however, need to be considered prior to choosing between the Poisson and Gaussian distribution to estimate the likelihood ratio, because each was advantageous under different circumstances. Once the control limit was exceeded, activity concentrations were estimated from the SR control chart using the slope of the control chart on a semi-logarithmic plot. Five of nine test solutions for the Poisson SR control chart produced concentration estimates within 30% of the actual value, but the worst case was 263.2% different than the actual value. The estimations for the Gaussian SR control chart were much more precise, with six of eight solutions producing estimates within 30%. Although the activity concentrations estimations were only mediocre for the Poisson SR control chart and satisfactory for the Gaussian SR control chart, these results demonstrate that a relationship exists between activity concentration and the SR control chart magnitude that can be exploited to determine the activity concentration from the SR control chart. More complex methods should be investigated to improve activity concentration estimations from the SR control charts.

Transarterial Coil-Augmented Onyx Embolization for Brain Arteriovenous Malformation

PubMed Central

Gao, Xu; Liang, Guobiao; Li, Zhiqing; Wang, Xiaogang; Yu, Chunyong; Cao, Peng; Chen, Jun; Li, Jingyuan

2014-01-01

Summary Onyx has been widely adopted for the treatment of arteriovenous malformations (AVMs). However, its control demands operators accumulate a considerable learning curve. We describe our initial experience using a novel injection method for the embolization of AVMs. We retrospectively reviewed the data of all 22 patients with brain AVMs (12 men, 10 women; age range, 12-68 years; mean age, 43.2 years) treated by the transarterial coil-augmented Onyx injection technique. The size of the AVMs ranged from 25 mm to 70 mm (average 35.6 mm). The technical feasibility of the procedure, procedure-related complications, angiographic results, and clinical outcome were evaluated. In every case, endovascular treatment (EVT) was completed. A total of 31 sessions were performed, with a mean injection volume of 6.1 mL (range, 1.5-16.0 mL). An average of 96.7% (range 85%-100%) estimated size reduction was achieved, and 18 AVMs could be completely excluded by EVT alone. The results remained stable on follow-up angiograms. A procedural complication occurred in one patient, with permanent mild neurologic deficit. Our preliminary series demonstrated that the coil-augmented Onyx injection technique is a valuable adjunct achieving excellent nidal penetration and improving the safety of the procedure. PMID:24556304

New algorithms and methods to estimate maximum-likelihood phylogenies: assessing the performance of PhyML 3.0.

PubMed

Guindon, Stéphane; Dufayard, Jean-François; Lefort, Vincent; Anisimova, Maria; Hordijk, Wim; Gascuel, Olivier

2010-05-01

PhyML is a phylogeny software based on the maximum-likelihood principle. Early PhyML versions used a fast algorithm performing nearest neighbor interchanges to improve a reasonable starting tree topology. Since the original publication (Guindon S., Gascuel O. 2003. A simple, fast and accurate algorithm to estimate large phylogenies by maximum likelihood. Syst. Biol. 52:696-704), PhyML has been widely used (>2500 citations in ISI Web of Science) because of its simplicity and a fair compromise between accuracy and speed. In the meantime, research around PhyML has continued, and this article describes the new algorithms and methods implemented in the program. First, we introduce a new algorithm to search the tree space with user-defined intensity using subtree pruning and regrafting topological moves. The parsimony criterion is used here to filter out the least promising topology modifications with respect to the likelihood function. The analysis of a large collection of real nucleotide and amino acid data sets of various sizes demonstrates the good performance of this method. Second, we describe a new test to assess the support of the data for internal branches of a phylogeny. This approach extends the recently proposed approximate likelihood-ratio test and relies on a nonparametric, Shimodaira-Hasegawa-like procedure. A detailed analysis of real alignments sheds light on the links between this new approach and the more classical nonparametric bootstrap method. Overall, our tests show that the last version (3.0) of PhyML is fast, accurate, stable, and ready to use. A Web server and binary files are available from http://www.atgc-montpellier.fr/phyml/.

[Experiences in the treatment of benign prostatic hyperplasia with high power potassium-titanyl-phosphate (KTP) laser].

PubMed

Lipiński, Marek I; Peszyński-Drews, Cezary; Jeromin, Marek Z; Jeromin, Leszek M

2006-01-01

Benign prostatic hyperplasia (BPH) exist in about 70% men after 60 years old. High power KTP laser is a new tool for the treatment of BPH. 49 men were treated by photoselective vaporisation of the prostate (PVP) from August 2003 to May 2004. Thirty patients with follow-up period longer than 12 weeks (12 to 26 weeks) were analyzed. Preoperative prostate volume ranged from 31 to 136 cc. PSA range, estimated before treatment, was normal in all patients (pts). International Prostate Symptom Score (I-PSS) estimated before treatment was over 24 and Quality of Life (QoL) was over 3 in all pts. The maximum peak urinary flow (Qmax) before treatment ranged from 7.2 to 14.1 ml/s. One patient was catheterized with Foley catheter at the finish of the procedure. Two pts required catheterization in the first day after treatment. In two pts increasing of body temperature to 38 degrees C was observed in the first day after treatment. Twenty four hours after treatment haematuria required catheterization was observed in one patient. Seven days after treatment in 4 pts massive haematuria was observed (two required hospitalisation). In one patient because of urinary retention 4 weeks after PVP transurethral resection of the prostate was performed. Four weeks after PVP I-PSS decreased from 24 to 20 and after 12 weeks to 15. The Qmax increased and ranged from 11.3 ml/s to 17.1 ml/s 4 weeks after PVP and 12 weeks after PVP ranged from 15.1 to 22.8 ml/s. Photoselective vaporization of the prostate reduces I-PSS in all patients 12 weeks after procedure. Short follow-up period and a limited number of patients in study group cannot lead to ultimate conclusions. However the results encourage to undertaking further studies on PVP for the treatment of BPH.

Alternative complement pathway activation during invasive coronary procedures in acute myocardial infarction and stable angina pectoris.

PubMed

Horváth, Zsófia; Csuka, Dorottya; Vargova, Katarina; Kovács, Andrea; Leé, Sarolta; Varga, Lilian; Préda, István; Tóth Zsámboki, Emese; Prohászka, Zoltán; Kiss, Róbert Gábor

2016-12-01

The effect of invasive percutaneous coronary procedures on complement activation has not been elucidated. We enrolled stable angina patients with elective percutaneous coronary intervention (SA-PCI, n=24), diagnostic coronary angiography (CA, n=52) and 23 patients with ST segment elevation myocardial infarction and primary PCI (STEMI-PCI). Complement activation products (C1rC1sC1inh, C3bBbP and SC5b-9) were measured on admission, 6 and 24h after coronary procedures. The alternative pathway product, C3bBbP significantly and reversibly increased 6h after elective PCI (baseline: 7.81AU/ml, 6h: 16.09AU/ml, 24h: 4.27AU/ml, p<0.01, n=23) and diagnostic angiography (baseline: 6.13AU/ml, 6h: 12.08AU/ml, 24h: 5.4AU/ml, p<0.01, n=52). Six hour C3bBbP values correlated with post-procedural CK, creatinine level and the applied contrast material volume (r=0.41, r=0.4, r=0.3, p<0.05, respectively). In STEMI-PCI, baseline C3bBbP level was higher, compared to SA-PCI or CA patients (11.33AU/ml vs. 7.81AU/ml or 6.13AU/ml, p<0.001). Similarly, the terminal complex (SC5b-9) level was already elevated at baseline compared to SA-PCI group (3.49AU/ml vs. 1.87AU/ml, p=0.011). Complement pathway products did not increase further after primary PCI. Elective coronary procedures induced transient alternative complement pathway activation, influenced by the applied contrast volume. In STEMI, the alternative complement pathway is promptly activated during the atherothrombotic event and PCI itself had no further detectable effect. Copyright © 2016 Elsevier B.V. All rights reserved.

Simulation Experiment Description Markup Language (SED-ML) Level 1 Version 3 (L1V3).

PubMed

Bergmann, Frank T; Cooper, Jonathan; König, Matthias; Moraru, Ion; Nickerson, David; Le Novère, Nicolas; Olivier, Brett G; Sahle, Sven; Smith, Lucian; Waltemath, Dagmar

2018-03-19

The creation of computational simulation experiments to inform modern biological research poses challenges to reproduce, annotate, archive, and share such experiments. Efforts such as SBML or CellML standardize the formal representation of computational models in various areas of biology. The Simulation Experiment Description Markup Language (SED-ML) describes what procedures the models are subjected to, and the details of those procedures. These standards, together with further COMBINE standards, describe models sufficiently well for the reproduction of simulation studies among users and software tools. The Simulation Experiment Description Markup Language (SED-ML) is an XML-based format that encodes, for a given simulation experiment, (i) which models to use; (ii) which modifications to apply to models before simulation; (iii) which simulation procedures to run on each model; (iv) how to post-process the data; and (v) how these results should be plotted and reported. SED-ML Level 1 Version 1 (L1V1) implemented support for the encoding of basic time course simulations. SED-ML L1V2 added support for more complex types of simulations, specifically repeated tasks and chained simulation procedures. SED-ML L1V3 extends L1V2 by means to describe which datasets and subsets thereof to use within a simulation experiment.

Comparison of vials and prefilled pens of a rapid-acting insulin analog on pharmacy budgets in a long-term care setting.

PubMed

Eby, Elizabeth L; Smolen, Lee J; Pitts, Amber C; Krueger, Linda A; Andrews, Jeffrey Scott

2014-12-01

Estimate budgetary impact for skilled nursing facility converting from individual patient supply (IPS) delivery of rapid-acting insulin analog (RAIA) 10-mL vials or 3-mL prefilled pens to 3-mL vials. A budget-impact model used insulin volume purchased and assumptions of length of stay (LOS), daily RAIA dose, and delivery protocol to estimate the cost impact of using 3-mL vials. Skilled nursing facility. Medicare Part A patients. Simulations conducted using 12-month current and future scenarios. Comparisons of RAIA use for 13- and 28-day LOS. RAIA costs and savings, waste reduction. For patients with 13-day LOS using 20 units/day of IPS insulin, the model estimated a 70% reduction in RAIA costs and units purchased and a 95% waste reduction for the 3-mL vial compared with the 10-mL vial. The estimated costs for prefilled pen use were 58% lower than for use of 10-mL vials. The incremental savings associated with 3-mL vial use instead of prefilled pens was 28%, attributable to differences in per-unit cost of insulin in vials versus prefilled pens. Using a more conservative scenario of 28-day LOS at 20 units/day, the model estimated a 40% reduction in RAIA costs and units purchased, resulting in a 91% reduction in RAIA waste for the 3-mL vial, compared with 10-mL vial. Budget-impact analysis of conversion from RAIA 10-mL vials or 3-mL prefilled pens to 3-mL vials estimated reductions in both insulin costs and waste across multiple scenarios of varying LOS and patient daily doses for skilled nursing facility stays.

Prospective study of lidocaine, bupivacaine, and epinephrine levels and blood loss in patients undergoing liposuction and abdominoplasty.

PubMed

Swanson, Eric

2012-09-01

Bupivacaine levels have not been measured in cosmetic surgery patients to establish safety. Blood loss has been underestimated using the small volumes present in the aspirate. The proportion of wetting solution removed by liposuction has not been reliably ascertained. To remedy these deficiencies, a prospective study was undertaken among 322 consecutive patients presenting for superwet ultrasonic liposuction and/or abdominoplasty, and other combined procedures, using infusions containing 0.05% lidocaine (liposuction) and/or 0.025% bupivacaine (abdominoplasty) with 1:500,000 epinephrine. Plasma levels of lidocaine, bupivacaine, and epinephrine were studied in a subset of 76 consecutive patients, including hourly intraoperative samples in 39 consecutive patients. Anesthetic levels were also measured in 12 consecutive patients during the 24-hour period after infusion. The maximum lidocaine dose was 3243 mg and the maximum level was 2.10 μg/ml. The maximum bupivacaine dose was 550 mg and the maximum level was 0.81 μg/ml. No clinical toxicity was encountered. Estimated blood loss from liposuction was 217.5 cc + 187 cc/liter of aspirate (r = 0.65). Abdominoplasty added 290 cc of blood loss, on average. The mean proportion of wetting solution removed by liposuction was 9.8 percent. Bupivacaine may be safely used in cosmetic surgery. A concentration of 1:500,000 epinephrine is safe and effective when administered as part of a wetting solution that is limited to less than 5 liters. Estimated blood loss is higher than previous estimates based on lipocrits. Combination procedures are safe.

Transvesical robotic simple prostatectomy: initial clinical experience.

PubMed

Leslie, Scott; Abreu, Andre Luis de Castro; Chopra, Sameer; Ramos, Patrick; Park, Daniel; Berger, Andre K; Desai, Mihir M; Gill, Inderbir S; Aron, Monish

2014-08-01

Despite significant developments in transurethral surgery for benign prostatic hyperplasia (BPH), simple prostatectomy remains an excellent option for patients with large glands. To describe our technique of transvesical robotic simple prostatectomy (RSP). From May 2011 to April 2013, 25 patients underwent RSP. We performed RSP using our technique. Baseline demographics, pathology data, perioperative complications, 90-d complications, and functional outcomes were assessed. Mean patient age was 72.9 yr (range: 54-88), baseline International Prostate Symptom Score (IPSS) was 23.9 (range: 9-35), prostate volume was 149.6 ml (range: 91-260), postvoid residual (PVR) was 208.1 ml (range: 72-800), maximum flow rate (Qmax) was 11.3 ml/s, and preoperative prostate-specific antigen was 9.4 ng/ml (range: 1.9-56.3). Eight patients were catheter dependent before surgery. Mean operative time was 214 min (range: 165-345), estimated blood loss was 143 ml (range: 50-350), and the hospital stay was 4 d (range: 2-8). There were no intraoperative complications and no conversions to open surgery. Five patients had a concomitant robotic procedure performed. Early functional outcomes demonstrated significant improvement from baseline with an 85% reduction in mean IPSS (p<0.0001), an 82.2% reduction in mean PVR (p=0.014), and a 77% increase in mean Qmax (p=0.20). This study is limited by small sample size and short follow-up period. One patient had a urinary tract infection; two had recurrent hematuria, one requiring transfusion; one patient had clot retention and extravasation, requiring reoperation. Our technique of RSP is safe and effective. Good functional outcomes suggest it is a viable option for BPH and larger glands and can be used for patients requiring concomitant procedures. We describe the technique and report the initial results of a series of cases of transvesical robotic simple prostatectomy. The procedure is both feasible and safe and a good option for benign prostatic hyperplasia with larger glands. Copyright © 2013 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Hand rub dose needed for a single disinfection varies according to product: a bias in benchmarking using indirect hand hygiene indicator.

PubMed

Girard, Raphaële; Aupee, Martine; Erb, Martine; Bettinger, Anne; Jouve, Alice

2012-12-01

The 3ml volume currently used as the hand hygiene (HH) measure has been explored as the pertinent dose for an indirect indicator of HH compliance. A multicenter study was conducted in order to ascertain the required dose using different products. The average contact duration before drying was measured and compared with references. Effective hand coverage had to include the whole hand and the wrist. Two durations were chosen as points of reference: 30s, as given by guidelines, and the duration validated by the European standard EN 1500. Each product was to be tested, using standardized procedures, by three nosocomial infection prevention teams, for three different doses (3, 2 and 1.5ml). Data from 27 products and 1706 tests were analyzed. Depending on the product, the dose needed to ensure a 30-s contact duration in 75% of tests ranging from 2ml to more than 3ml, and to ensure a contact duration exceeding the EN 1500 times in 75% of tests ranging from 1.5ml to more than 3ml. The aftermath interpretation is the following: if different products are used, the volume utilized does not give an unbiased estimation of the HH compliance. Other compliance evaluation methods remain necessary for efficient benchmarking. Copyright © 2012 Ministry of Health, Saudi Arabia. Published by Elsevier Ltd. All rights reserved.

A novel method for blood volume estimation using trivalent chromium in rabbit models.

PubMed

Baby, Prathap Moothamadathil; Kumar, Pramod; Kumar, Rajesh; Jacob, Sanu S; Rawat, Dinesh; Binu, V S; Karun, Kalesh M

2014-05-01

Blood volume measurement though important in management of critically ill-patients is not routinely estimated in clinical practice owing to labour intensive, intricate and time consuming nature of existing methods. The aim was to compare blood volume estimations using trivalent chromium [(51)Cr(III)] and standard Evans blue dye (EBD) method in New Zealand white rabbit models and establish correction-factor (CF). Blood volume estimation in 33 rabbits was carried out using EBD method and concentration determined using spectrophotometric assay followed by blood volume estimation using direct injection of (51)Cr(III). Twenty out of 33 rabbits were used to find CF by dividing blood volume estimation using EBD with blood volume estimation using (51)Cr(III). CF is validated in 13 rabbits by multiplying it with blood volume estimation values obtained using (51)Cr(III). The mean circulating blood volume of 33 rabbits using EBD was 142.02 ± 22.77 ml or 65.76 ± 9.31 ml/kg and using (51)Cr(III) was estimated to be 195.66 ± 47.30 ml or 89.81 ± 17.88 ml/kg. The CF was found to be 0.77. The mean blood volume of 13 rabbits measured using EBD was 139.54 ± 27.19 ml or 66.33 ± 8.26 ml/kg and using (51)Cr(III) with CF was 152.73 ± 46.25 ml or 71.87 ± 13.81 ml/kg (P = 0.11). The estimation of blood volume using (51)Cr(III) was comparable to standard EBD method using CF. With further research in this direction, we envisage human blood volume estimation using (51)Cr(III) to find its application in acute clinical settings.

Environmentally safe sewage sludge disposal: the impact of liming on the behaviour of Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn.

PubMed

Scancar, J; Milacic, R; Strazar, M; Burica, O; Bukovec, P

2001-02-01

Dewatered sewage sludge containing relatively high total concentrations of Cr (945 micrograms ml-1), Cu (523 micrograms ml-1), Ni (1186 micrograms ml-1) and Zn (2950 micrograms ml-1) was treated with quicklime and sawdust for sludge disinfection and post-stabilisation. The mobility of the heavy metals in the sludge samples was assessed by applying a modified five-step Tessier sequential extraction procedure. Water was added as a first step for estimation of the proportion of the easily soluble metal fractions. To check the precision of the analytical work the concentrations of heavy metals in steps 1-6 of the extraction procedure were summed and compared to the total metal concentrations. The mass balance agreed within +/- 3% for Cd, Cu, Cr, and Zn and within +/- 5% for Ni, Pb, Fe and Mn. Data from the partitioning study indicate that in the lime-treated sludge at a pH of 12 the mobility of Cu and Ni notably increased with the solubilisation of these metals from their organic and/or carbonate and Fe and Mn oxide and hydroxide fractions, respectively. Liming slightly decreased the proportion of other heavy metals in the easily soluble fractions while its impact on the partitioning between other sludge phases was almost insignificant. Due to the increased solubility of Ni and Cu as well as potential Cr oxidation at high pH, liming cannot be recommended for sludge disinfection. Addition of sawdust did not change the heavy metal partitioning.

Pros and Cons of 3D Image Fusion in Endovascular Aortic Repair: A Systematic Review and Meta-analysis.

PubMed

Goudeketting, Seline R; Heinen, Stefan G H; Ünlü, Çağdaş; van den Heuvel, Daniel A F; de Vries, Jean-Paul P M; van Strijen, Marco J; Sailer, Anna M

2017-08-01

To systematically review and meta-analyze the added value of 3-dimensional (3D) image fusion technology in endovascular aortic repair for its potential to reduce contrast media volume, radiation dose, procedure time, and fluoroscopy time. Electronic databases were systematically searched for studies published between January 2010 and March 2016 that included a control group describing 3D fusion imaging in endovascular aortic procedures. Two independent reviewers assessed the methodological quality of the included studies and extracted data on iodinated contrast volume, radiation dose, procedure time, and fluoroscopy time. The contrast use for standard and complex endovascular aortic repairs (fenestrated, branched, and chimney) were pooled using a random-effects model; outcomes are reported as the mean difference with 95% confidence intervals (CIs). Seven studies, 5 retrospective and 2 prospective, involving 921 patients were selected for analysis. The methodological quality of the studies was moderate (median 17, range 15-18). The use of fusion imaging led to an estimated mean reduction in iodinated contrast of 40.1 mL (95% CI 16.4 to 63.7, p=0.002) for standard procedures and a mean 70.7 mL (95% CI 44.8 to 96.6, p<0.001) for complex repairs. Secondary outcome measures were not pooled because of potential bias in nonrandomized data, but radiation doses, procedure times, and fluoroscopy times were lower, although not always significantly, in the fusion group in 6 of the 7 studies. Compared with the control group, 3D fusion imaging is associated with a significant reduction in the volume of contrast employed for standard and complex endovascular aortic procedures, which can be particularly important in patients with renal failure. Radiation doses, procedure times, and fluoroscopy times were reduced when 3D fusion was used.

Using VS30 to Estimate Station ML Adjustments (dML)

NASA Astrophysics Data System (ADS)

Yong, A.; Herrick, J.; Cochran, E. S.; Andrews, J. R.; Yu, E.

2017-12-01

Currently, new seismic stations added to a regional seismic network cannot be used to calculate local or Richter magnitude (ML) until a revised region-wide amplitude decay function is developed. The new station must record a minimum number of local and regional events that meet specific amplitude requirements prior to re-calibration of the amplitude decay function. Therefore, there can be significant delay between when a new station starts contributing real-time waveform packets and when the data can be included in magnitude estimation. The station component adjustments (dML; Uhrhammer et al., 2011) are calculated after first inverting for a new regional amplitude decay function, constrained by the sum of dML for long-running stations. Here, we propose a method to calculate an initial dML using known or proxy values of seismic site conditions. For site conditions, we use the time-averaged shear-wave velocity (VS) of the upper 30 m (VS30). We solve for dML as described in Equation (1) by Uhrhammer et al. (2011): ML = log (A) - log A0 (r) + dML, where A is the maximum Wood and Anderson (1925) trace amplitude (mm), r is the distance (km), and dML is the station adjustment. Measured VS30 and estimated dML data are comprised of records from 887 horizontal components (east-west and north-south orientations) from 93 seismic monitoring stations in the California Integrated Seismic Network. VS30 values range from 202 m/s to 1464 m/s and dML range from -1.10 to 0.39. VS30 and dML exhibit a positive correlation coefficient (R = 0.72), indicating that as VS30 increases, dML increases. This implies that greater site amplification (i.e., lower VS30) results in smaller ML. When we restrict VS30 < 760 m/s to focus on dML at soft soil to soft rock sites, R increases to 0.80. In locations where measured VS30 data are unavailable, we evaluate the use of proxy-based VS30 estimates based on geology, topographic slope and terrain classification, as well as other hybridized methods. Measured VS30 data or proxy-based VS30 estimates can be used for initial dML estimates that allow new stations to contribute to regional network ML estimates immediately without the need to wait until a minimum set of earthquake data has been recorded.

Measurement of glomerular filtration rate, renal plasma flow, and endogenous creatinine clearance in cheetahs (Acinonyx jubatus jubatus).

PubMed

Holder, Erin Hall; Citino, Scott B; Businga, Nancy; Cartier, Leslie; Brown, Scott A

2004-06-01

Glomerular filtration rate (GFR), renal plasma flow (RPF), and the endogenous creatinine clearance (CCr) rate were determined in 13 captive cheetahs, Acinonyx jubatus jubatus (seven females and six males, 1.5-7.5 yr of age, x = 5.02 yr), during general anesthesia with Telazol and isoflurane by measuring the urinary clearances of inulin, para-aminohipppuric acid, and endogenous creatinine, respectively. Methods to determine GFR, RPF, and endogenous CCr in captive cheetahs were evaluated, and the relationship between GFR and CCr for this species was determined. The GFR and the RPF were stable during the procedure, with mean values of 1.59+/-0.17 ml/min/kg body weight and 5.12+/-1.15 ml/min/kg body weight, respectively. Although the mean value for CCr (1.47+/-0.20 ml/min/kg body weight) was significantly less than the corresponding value for GFR, the mean difference (0.11+/-0.02 ml/min/kg weight) between the two measurements was slight, and the values were highly correlated (R2 = 0.928; P < 0.0001). The measurement of CCr in cheetahs should provide a reliable estimate of GFR, facilitating the early detection of renal disease in this species.

Effects of melatonin on the acute inflammatory response associated with endoscopic retrograde cholangiopancreatography: A randomized, double-blind, placebo-controlled trial.

PubMed

Hernández-Velázquez, B; Camara-Lemarroy, C R; González-González, J A; García-Compean, D; Monreal-Robles, R; Cordero-Pérez, P; Muñoz-Espinosa, L E

2016-01-01

Endoscopic retrograde cholangiopancreatography (ERCP) is associated with an acute inflammatory response and melatonin has a variety of immunomodulatory and antioxidant effects studied experimentally in pancreatobiliary pathology. The aim of our study was to evaluate the effects of peri-procedural administration of melatonin on the inflammatory response and lipid peroxidation associated with ERCP. In this proof-of-concept clinical trial, 37 patients with a high probability of choledocholithiasis were randomized to receive peri-procedure (ERCP) melatonin or placebo. We measured the serum concentration of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), lipid peroxidation, amylase, and liver function tests 24h before and after the procedure. We found no pre-procedure or post-procedure differences between the melatonin group or the placebo group (P>.05) in the serum concentrations of TNF-alpha (melatonin: 153.8 vs. 149.4ng/m; placebo: 103.5 vs. 107.3ng/ml), IL-6 (melatonin: 131.8 vs. 133.3ng/ml; placebo: 177.8 vs. 197.8ng/ml), or VEGF (melatonin: 157.3 vs. 157.8pg/ml; placebo: 97.3 vs. 97.8pg/ml), or in relation to lipid peroxidation (melatonin: 39.2 vs. 72.3μg/ml; placebo: 66.4 vs. 90.5μg/ml). After ERCP, a significant decrease in the AST, ALT, and total bilirubin levels was found only in the melatonin group (P<.05). The administration of melatonin was safe and tolerable. Melatonin is safe and tolerable in patients undergoing ERCP, but it does not appear to affect inflammatory cytokine concentrations or lipid peroxidation. Copyright © 2016 Asociación Mexicana de Gastroenterología. Publicado por Masson Doyma México S.A. All rights reserved.

Measurement of testicular volume in smaller testes: how accurate is the conventional orchidometer?

PubMed

Lin, Chih-Chieh; Huang, William J S; Chen, Kuang-Kuo

2009-01-01

The aim of this study was to evaluate the accuracy of different methods, including the Seager orchidometer (SO) and ultrasonography (US), for assessing testicular volume of smaller testes (testes volume less than 18 mL). Moreover, the equations used for the calculations--the Hansen formula (length [L] x width [W](2) x 0.52, equation A), the prolate ellipsoid formula (L x W x height [H] x 0.52, equation B), and the Lambert equation (L x W x H x 0.71, equation C)--were also examined and compared with the gold standard testicular volume obtained by water displacement (Archimedes principle). In this study, 30 testes from 15 men, mean age 75.3 (+/-8.3) years, were included. They all had advanced prostate cancer and were admitted for orchiectomy. Before the procedure, all the testes were assessed using SO and US. The dimensions were then input into each equation to obtain the volume estimates. The testicular volume by water displacement was 8.1 +/- 3.5 mL. Correlation coefficients (R(2)) of the 2 different methods (SO, US) to the gold standard were 0.70 and 0.85, respectively. The calculated testicular volumes were 9.2 +/- 3.9 mL (measured by SO, equation A), 11.9 +/- 5.2 mL (measured by SO, equation C), 7.3 +/- 4.2 mL (measured by US, equation A), 6.5 +/- 3.3 mL (measured by US, equation B) and 8.9 +/- 4.5 mL (measured by US, equation C). Only the mean size measured by US and volume calculated with the Hansen equation (equation A) and the mean size measured by US and volume calculated with the Lambert equation (equation C) showed no significant differences when compared with the volumes estimated by water displacement (mean difference 0.81 mL, P = .053, and 0.81 mL, P = .056, respectively). Based on our measurements, we categorized testicular volume by different cutoff values (7.0 mL, 7.5 mL, 8.0 mL, and 8.5 mL) to calculate a new constant for use in the Hansen equation. The new constant was 0.59. We then reexamined the equations using the new 0.59 constant, and found that the equation Volume (V) = L x W(2) x 0.59 was the best for describing testicular volume among our subjects (difference between the new equation and the gold standard of water displacement = 0.19 mL, P = .726). We also found that US was more precise in measuring testicular dimensions. We propose a new formula, V = L x W(2) x 0.59, to assess the volumes of smaller testes.

A preliminary report on the rapid fluorimetric determination of uranium in low-grade ores

USGS Publications Warehouse

Grimaldi, F.S.; Levine, Harry

1950-01-01

A simple and very rapid fluorimetric procedure is described for the determination of uranium in low-grade shale and phosphate ores. The best working range is from 0.001 to about 0.04 percent U. The procedure employs batch extraction of uranium nitrate by ethyl acetate, using aluminum nitrate as the salting agent, prior to the visual fluorimetric estimation. The procedure is especially designed to save reagents; only 9.5 g of aluminum nitrate and 10 ml of ethyl acetate being used for one analysis. The solution of the sample by means of a fusion with NaOH-NaNO3 flux is rapid. After fusion the sample is immediately extracted without removing silica and other hydrolytic precipitates. Aluminum nitrate very effectively ties up fluoride and phosphate, thus eliminating steps required for their removal.

Systemic hypothermia to prevent radiocontrast nephropathy (from the COOL-RCN Randomized Trial).

PubMed

Stone, Gregg W; Vora, Kishor; Schindler, John; Diaz, Claro; Mann, Tift; Dangas, George; Best, Patricia; Cutlip, Donald E

2011-09-01

Radiocontrast nephropathy (RCN) develops in a substantial proportion of patients with chronic kidney disease (CKD) after invasive cardiology procedures and is strongly associated with subsequent mortality and adverse outcomes. We sought to determine whether systemic hypothermia is effective in preventing RCN in patients with CKD. Patients at risk for RCN (baseline estimated creatinine clearance 20 to 50 ml/min) undergoing cardiac catheterization with iodinated contrast ≥50 ml were randomized 1:1 to hydration (control arm) versus hydration plus establishment of systemic hypothermia (33°C to 34°C) before first contrast injection and for 3 hours after the procedure. Serum creatinine levels at baseline, 24 hours, 48 hours, and 72 to 96 hours were measured at a central core laboratory. The primary efficacy end point was development of RCN, defined as an increase in serum creatinine by ≥25% from baseline. The primary safety end point was 30-day composite rate of adverse events consisting of death, myocardial infarction, dialysis, ventricular fibrillation, venous complication requiring surgery, major bleeding requiring transfusion ≥2 U, or rehospitalization. In total 128 evaluable patients (mean creatinine clearance 36.6 ml/min) were prospectively randomized at 25 medical centers. RCN developed in 18.6% of normothermic patients and in 22.4% of hypothermic patients (odds ratio 1.27, 95% confidence interval 0.53 to 3.00, p = 0.59). The primary 30-day safety end point occurred in 37.1% versus 37.9% of normothermic and hypothermic patients, respectively (odds ratio 0.97, 95% confidence interval 0.47 to 1.98, p = 0.93). In conclusion, in patients with CKD undergoing invasive cardiology procedures, systemic hypothermia is safe but is unlikely to prevent RCN. Copyright © 2011 Elsevier Inc. All rights reserved.

Multi-views Fusion CNN for Left Ventricular Volumes Estimation on Cardiac MR Images.

PubMed

Luo, Gongning; Dong, Suyu; Wang, Kuanquan; Zuo, Wangmeng; Cao, Shaodong; Zhang, Henggui

2017-10-13

Left ventricular (LV) volumes estimation is a critical procedure for cardiac disease diagnosis. The objective of this paper is to address direct LV volumes prediction task. In this paper, we propose a direct volumes prediction method based on the end-to-end deep convolutional neural networks (CNN). We study the end-to-end LV volumes prediction method in items of the data preprocessing, networks structure, and multi-views fusion strategy. The main contributions of this paper are the following aspects. First, we propose a new data preprocessing method on cardiac magnetic resonance (CMR). Second, we propose a new networks structure for end-to-end LV volumes estimation. Third, we explore the representational capacity of different slices, and propose a fusion strategy to improve the prediction accuracy. The evaluation results show that the proposed method outperforms other state-of-the-art LV volumes estimation methods on the open accessible benchmark datasets. The clinical indexes derived from the predicted volumes agree well with the ground truth (EDV: R=0.974, RMSE=9.6ml; ESV: R=0.976, RMSE=7.1ml; EF: R=0.828, RMSE =4.71%). Experimental results prove that the proposed method has high accuracy and efficiency on LV volumes prediction task. The proposed method not only has application potential for cardiac diseases screening for large-scale CMR data, but also can be extended to other medical image research fields.

Freeze-drying process design by manometric temperature measurement: design of a smart freeze-dryer.

PubMed

Tang, Xiaolin Charlie; Nail, Steven L; Pikal, Michael J

2005-04-01

To develop a procedure based on manometric temperature measurement (MTM) and an expert system for good practices in freeze drying that will allow development of an optimized freeze-drying process during a single laboratory freeze-drying experiment. Freeze drying was performed with a FTS Dura-Stop/Dura-Top freeze dryer with the manometric temperature measurement software installed. Five percent solutions of glycine, sucrose, or mannitol with 2 ml to 4 ml fill in 5 ml vials were used, with all vials loaded on one shelf. Details of freezing, optimization of chamber pressure, target product temperature, and some aspects of secondary drying are determined by the expert system algorithms. MTM measurements were used to select the optimum shelf temperature, to determine drying end points, and to evaluate residual moisture content in real-time. MTM measurements were made at 1 hour or half-hour intervals during primary drying and secondary drying, with a data collection frequency of 4 points per second. The improved MTM equations were fit to pressure-time data generated by the MTM procedure using Microcal Origin software to obtain product temperature and dry layer resistance. Using heat and mass transfer theory, the MTM results were used to evaluate mass and heat transfer rates and to estimate the shelf temperature required to maintain the target product temperature. MTM product dry layer resistance is accurate until about two-thirds of total primary drying time is over, and the MTM product temperature is normally accurate almost to the end of primary drying provided that effective thermal shielding is used in the freeze-drying process. The primary drying times can be accurately estimated from mass transfer rates calculated very early in the run, and we find the target product temperature can be achieved and maintained with only a few adjustments of shelf temperature. The freeze-dryer overload conditions can be estimated by calculation of heat/mass flow at the target product temperature. It was found that the MTM results serve as an excellent indicator of the end point of primary drying. Further, we find that the rate of water desorption during secondary drying may be accurately measured by a variation of the basic MTM procedure. Thus, both the end point of secondary drying and real-time residual moisture may be obtained during secondary drying. Manometric temperature measurement and the expert system for good practices in freeze drying does allow development of an optimized freeze-drying process during a single laboratory freeze-drying experiment.

Nonlinear phase noise tolerance for coherent optical systems using soft-decision-aided ML carrier phase estimation enhanced with constellation partitioning

NASA Astrophysics Data System (ADS)

Li, Yan; Wu, Mingwei; Du, Xinwei; Xu, Zhuoran; Gurusamy, Mohan; Yu, Changyuan; Kam, Pooi-Yuen

2018-02-01

A novel soft-decision-aided maximum likelihood (SDA-ML) carrier phase estimation method and its simplified version, the decision-aided and soft-decision-aided maximum likelihood (DA-SDA-ML) methods are tested in a nonlinear phase noise-dominant channel. The numerical performance results show that both the SDA-ML and DA-SDA-ML methods outperform the conventional DA-ML in systems with constant-amplitude modulation formats. In addition, modified algorithms based on constellation partitioning are proposed. With partitioning, the modified SDA-ML and DA-SDA-ML are shown to be useful for compensating the nonlinear phase noise in multi-level modulation systems.

Gastric emptying evaluation by ultrasound prior colonoscopy: An easy tool following bowel preparation

PubMed Central

Coriat, Romain; Polin, Vanessa; Oudjit, Ammar; Henri, Franck; Dhooge, Marion; Leblanc, Sarah; Delchambre, Chantal; Esch, Anouk; Tabouret, Tessa; Barret, Maximilien; Prat, Frédéric; Chaussade, Stanislas

2014-01-01

AIM: To investigate the gastric emptying after bowel preparation to allow general anaesthesia. METHODS: A prospective, non-comparative, and non-randomized trial was performed and registered on Eudra CT database (2011-002953-80) and on www.trial.gov (NCT01398098). All patients had a validated indication for colonoscopy and a preparation using sodium phosphate (NaP) tablets. The day of the procedure, patients took 4 tablets with 250 mL of water every 15 min, three times. The gastric volume was estimated every 15 min from computed antral surfaces and weight according to the formula of Perlas et al (Anesthesiology, 2009). Colonoscopy was performed within the 6 h following the last intake. RESULTS: Thirty patients were prospectively included in the study from November 2011 to May 2012. The maximum volume of the antrum was 212 mL, achieved 15 min after the last intake. 24%, 67% and 92% of subjects had an antral volume below 20 mL at 60, 120 and 150 min, respectively. 81% of patients had a Boston score equal to 2 or 3 in each colonic segment. No adverse events leading to treatment discontinuation were reported. CONCLUSION: Gastric volume evaluation appeared to be a simple and reliable method for the assessment of gastric emptying. Data allow considering the NaP tablets bowel preparation in the morning of the procedure and confirming that gastric emptying is achieved after two hours, allowing general anaesthesia. PMID:25309090

Infrared Light Structured Sensor 3D Approach to Estimate Kidney Volume: A Validation Study.

PubMed

Garisto, Juan; Bertolo, Riccardo; Dagenais, Julien; Kaouk, Jihad

2018-06-26

To validate a new procedure for the three-dimensional (3D) estimation of total renal parenchyma volume (RPV) using a structured-light infrared laser sensor. To evaluate the accuracy of the sensor for assessing renal volume, we performed three experiments. Twenty freshly excised porcine kidneys were obtained. Experiment A, the water displacement method was used to obtain a determination of the RPV after immersing every kidney into 0.9% saline. Thereafter a structured sensor (Occipital, San Francisco, CA, USA) was used to scan the kidney. Kidney sample surface was presented initially as a mesh and then imported into MeshLab (Visual Computing Lab, Pisa, Italy) software to obtain the surface volume. Experiment B, a partial excision of the kidney with measurement of the excised volume and remnant was performed. Experiment C, a renorrhaphy of the remnant kidney was performed then measured. Bias and limits of agreement (LOA) were determined using the Bland-Altman method. Reliability was assessed using the intraclass correlation coefficient (ICC). Experiment A, the sensor bias was -1.95 mL (LOA: -19.5 to 15.59, R2= 0.410) with slightly overestimating the volumes. Experiment B, remnant kidney after partial excision and excised kidney volume were measured showing a sensor bias of -0.5 mL (LOA -5.34 to 4.20, R2= 0.490) and -0.6 mL (LOA: -1.97.08 to 0.77, R2= 0.561), respectively. Experiment C, the sensor bias was -0.89 mL (LOA -12.9 to 11.1, R2= 0.888). ICC was 0.9998. The sensor is a reliable method for assessing total renal volume with high levels of accuracy. Copyright © 2018. Published by Elsevier Inc.

Laparoscopic ureteral reimplantation with Boari flap for the management of long- segment ureteral defect: A case series with review of the literature

PubMed Central

Bansal, Ankur; Sinha, Rahul Janak; Jhanwar, Ankur; Prakash, Gaurav; Purkait, Bimalesh; Singh, Vishwajeet

2017-01-01

Objective The incidence of ureteral stricture is showing a rising trend due to increased use of laparoscopic and upper urinary tract endoscopic procedures. Boari flap is the preferred method of repairing long- segment ureteral defects of 8–12 cm. The procedure has undergone change from classical open (transperitoneal and retroperitoneal) method to laparoscopic surgery and recently robotic surgery. Laparoscopic approach is cosmetically appealing, less morbid and with shorter hospital stay. In this case series, we report our experience of performing laparoscopic ureteral reimplantation with Boari flap in 3 patients. Material and methods This prospective study was conducted between January 2011 December 2014. The patients with a long- segment ureteral defect who had undergone laparoscopic Boari flap reconstruction were included in the study. Outcome of laparoscopic ureteral reimplantation with Boari flap for the manangement of long segment ureteral defect was evaluated. Results The procedure was performed on 3 patients, and male to female ratio was 1:2. One patient had bilateral and other two patient had left ureteral stricture. The mean length of ureteral stricture was 8.6 cm (range 8.2–9.2 cm). The mean operative time was 206 min (190 to 220 min). The average estimated blood loss was 100 mL (range 90–110 mL) and mean hospital stay was 6 days (range 5 to 7 days). The mean follow up was 19 months (range 17–22 months). None of the patients experienced any complication related to the procedure in perioperative period. Conclusion Laparoscopic ureteral reimplantation with Boari flap is safe, feasible and has excellent long term results. However, the procedure is technically challenging, requires extensive experience of intracorporeal suturing. PMID:28861304

Laparoscopic ureteral reimplantation with Boari flap for the management of long- segment ureteral defect: A case series with review of the literature.

PubMed

Bansal, Ankur; Sinha, Rahul Janak; Jhanwar, Ankur; Prakash, Gaurav; Purkait, Bimalesh; Singh, Vishwajeet

2017-09-01

The incidence of ureteral stricture is showing a rising trend due to increased use of laparoscopic and upper urinary tract endoscopic procedures. Boari flap is the preferred method of repairing long- segment ureteral defects of 8-12 cm. The procedure has undergone change from classical open (transperitoneal and retroperitoneal) method to laparoscopic surgery and recently robotic surgery. Laparoscopic approach is cosmetically appealing, less morbid and with shorter hospital stay. In this case series, we report our experience of performing laparoscopic ureteral reimplantation with Boari flap in 3 patients. This prospective study was conducted between January 2011 December 2014. The patients with a long- segment ureteral defect who had undergone laparoscopic Boari flap reconstruction were included in the study. Outcome of laparoscopic ureteral reimplantation with Boari flap for the manangement of long segment ureteral defect was evaluated. The procedure was performed on 3 patients, and male to female ratio was 1:2. One patient had bilateral and other two patient had left ureteral stricture. The mean length of ureteral stricture was 8.6 cm (range 8.2-9.2 cm). The mean operative time was 206 min (190 to 220 min). The average estimated blood loss was 100 mL (range 90-110 mL) and mean hospital stay was 6 days (range 5 to 7 days). The mean follow up was 19 months (range 17-22 months). None of the patients experienced any complication related to the procedure in perioperative period. Laparoscopic ureteral reimplantation with Boari flap is safe, feasible and has excellent long term results. However, the procedure is technically challenging, requires extensive experience of intracorporeal suturing.

Simple and rapid screening procedure for 143 new psychoactive substances by liquid chromatography-tandem mass spectrometry.

PubMed

Adamowicz, Piotr; Tokarczyk, Bogdan

2016-07-01

In recent years, many new psychoactive substances (NPS) from several drug classes have appeared on the drug market. These substances, also known as 'legal highs', belong to different chemical classes. Despite the increasing number of NPS, there are few comprehensive screening methods for their detection in biological specimens. In this context, the purpose of this study was to develop a fast and simple liquid chromatography-tandem mass spectrometry (LC-MS/MS) screening procedure for NPS in blood. The elaborated method allows the simultaneous screening of 143 compounds from different groups (number of compounds): cathinones (36), phenethylamines (26), tryptamines (18), piperazines (9), piperidines (2), synthetic cannabinoids (34), arylalkylamines (7), arylcyclohexylamines (3), aminoindanes (2), and other drugs (6). Blood samples (0.2 mL) were precipitated with acetonitrile (0.6 mL). The separation was achieved with gradient mobile phase of 0.1% formic acid in acetonitrile and 0.1% formic acid in water in 14 min. Detection of all compounds was based on multiple reaction monitoring (MRM) transitions. The total number of transitions monitored in dynamic mode was 432. The whole procedure was rapid and simple. The limits of detection (LODs) estimated for 104 compounds were in the range 0.01-3.09 ng/mL. The extraction recoveries determined for 32 compounds were from 1.8 to 133%. The procedure was successfully applied to the analysis of forensic blood samples in routine casework. The developed method should have wide applicability for rapid screening of new drugs of abuse in forensic or clinical samples. The procedure can be easily expanded for more substances. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

Inclusion of Exercise Intensities Above the Lactate Threshold in VO2/Running Speed Regression Does not Improve the Precision of Accumulated Oxygen Deficit Estimation in Endurance-Trained Runners

PubMed Central

Reis, Victor M.; Silva, António J.; Ascensão, António; Duarte, José A.

2005-01-01

The present study intended to verify if the inclusion of intensities above lactate threshold (LT) in the VO2/running speed regression (RSR) affects the estimation error of accumulated oxygen deficit (AOD) during a treadmill running performed by endurance-trained subjects. Fourteen male endurance-trained runners performed a sub maximal treadmill running test followed by an exhaustive supra maximal test 48h later. The total energy demand (TED) and the AOD during the supra maximal test were calculated from the RSR established on first testing. For those purposes two regressions were used: a complete regression (CR) including all available sub maximal VO2 measurements and a sub threshold regression (STR) including solely the VO2 values measured during exercise intensities below LT. TED mean values obtained with CR and STR were not significantly different under the two conditions of analysis (177.71 ± 5.99 and 174.03 ± 6.53 ml·kg-1, respectively). Also the mean values of AOD obtained with CR and STR did not differ under the two conditions (49.75 ± 8.38 and 45.8 9 ± 9.79 ml·kg-1, respectively). Moreover, the precision of those estimations was also similar under the two procedures. The mean error for TED estimation was 3.27 ± 1.58 and 3.41 ± 1.85 ml·kg-1 (for CR and STR, respectively) and the mean error for AOD estimation was 5.03 ± 0.32 and 5.14 ± 0.35 ml·kg-1 (for CR and STR, respectively). The results indicated that the inclusion of exercise intensities above LT in the RSR does not improve the precision of the AOD estimation in endurance-trained runners. However, the use of STR may induce an underestimation of AOD comparatively to the use of CR. Key Points It has been suggested that the inclusion of exercise intensities above the lactate threshold in the VO2/power regression can significantly affect the estimation of the energy cost and, thus, the estimation of the AOD. However data on the precision of those AOD measurements is rarely provided. We have evaluated the effects of the inclusion of those exercise intensities on the AOD precision. The results have indicated that the inclusion of exercise intensities above the lactate threshold in the VO2/running speed regression does not improve the precision of AOD estimation in endurance-trained runners. However, the use of sub threshold regressions may induce an underestimation of AOD comparatively to the use of complete regressions. PMID:24501560

Outcomes of transcatheter aortic valve replacement using a minimalist approach.

PubMed

Gurevich, Sergey; Oestreich, Brett; Kelly, Rosemary F; Mbai, Mackenzie; Bertog, Stefan; Ringsred, Karen; Lawton, Annette; Thooft, Brenda; Wagner, Julie; Garcia, Santiago

2018-03-01

Transcatheter Aortic Valve Replacement (TAVR) is increasingly performed using a minimalist approach under monitored anesthesia care (MAC). The safety of this approach remains controversial and adoption has been low in the US. The study cohort was comprised of 130 patients (98% male) who underwent TAVR between 4/2015 and 4/2017 at the Minneapolis VA. We compared the outcomes of 81 patients who underwent TAVR using a standard approach (standard TAVR) and 49 who underwent TAVR using a minimalist approach (minimalist TAVR). Outcome measures included device and procedural success, procedural efficiency, length of intensive care unit (ICU) and hospital stay, procedural complications and hospital readmissions. Mean age was 80 (±9) years and median (IQR) STS score was 5 (4-6). Access included transfemoral (n = 111, 85%) and alternative (n = 19, 15%). Minimalist TAVR was associated with reduced procedural time: median 101 min (IQR: 78-135) versus 127 min (IQR: 97-182, p = 0.03), fluoroscopy time: median 18 min (IQR: 12-26) versus 24 min (IQR: 16-38), p = 0.001), contrast volume 90 ml (IQR: 70-120 ml) versus 140 ml (IQR: 86-213 ml, p < 0.001). A minimalistic approach to TAVR is associated with improved procedural efficiency and reduced length of stay without compromising procedural success or clinical outcomes. Published by Elsevier Inc.

Aspirin for Prophylaxis Against Venous Thromboembolism After Orthopaedic Oncologic Surgery.

PubMed

Mendez, Gregory M; Patel, Yash M; Ricketti, Daniel A; Gaughan, John P; Lackman, Richard D; Kim, Tae Won B

2017-12-06

Patients who undergo orthopaedic oncologic surgical procedures are at increased risk of developing a venous thromboembolism (VTE). Guidelines from surgical societies are shifting to include aspirin as a postoperative VTE prophylactic agent. The purpose of this study was to review our experience using aspirin as postoperative VTE prophylaxis for orthopaedic oncologic surgical procedures. This study was a retrospective review of patients diagnosed with a primary malignant soft-tissue or bone tumor or metastatic carcinoma. Demographic information, histopathologic diagnosis, VTE history, surgical procedure, and VTE prophylaxis were analyzed. VTE rates in the overall and prophylactic-specific cohorts were recorded and compared. A total of 142 distinct surgical procedures in 130 patients were included. VTE prophylaxis with aspirin was used after 103 procedures, and non-aspirin prophylaxis was used after 39. In 33 cases, imaging was used to investigate for VTE because of clinical signs and symptoms. VTE developed after 7 (4.9%) of the 142 procedures. There were 6 deep venous thromboses (DVTs) and 1 pulmonary embolism, and 2 of the VTEs presented in patients with a VTE history. VTE developed in 2.9% (3) of the 103 aspirin cases and 10.3% (4) of the 39 non-aspirin cases. No patient in the aspirin group who had been diagnosed with metastatic carcinoma, malignant soft-tissue sarcoma, lymphoma, or multiple myeloma developed a VTE. Risk factors for VTE development included diabetes mellitus (odds ratio [OR] = 10.40, 95% confidence interval [CI] = 1.61 to 67.30), a history of VTE (OR = 7.26, 95% CI = 1.19 to 44.25), postoperative transfusion (OR = 34.50, 95% CI = 3.94 to 302.01), and estimated blood losses of 250 mL (OR = 1.50, 95% CI = 1.11 to 2.03), 500 mL (OR = 2.26, 95% CI = 1.23 to 4.13), and 1,000 mL (OR = 5.10, 95% CI = 1.52 to 17.04). Aspirin may be a suitable and effective option for VTE chemoprophylaxis in patients treated with orthopaedic oncologic surgery, especially those diagnosed with a soft-tissue sarcoma. Research with a more advanced study design is required. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Isolation, Cloning and Expression of the Genes for Microbial Polyurethane Degradation

DTIC Science & Technology

1991-05-31

utilizing lysing enzymes, Gluculase and Novozyme , digest the mycelium and produce protoplasts but also tend to digest the DNA. The detergent procedures did...at -20 ’C. Novozyme Procedure One liter of fresh HAFB-2F-Br culture, grown to saturation, was vacuum filtered through Whatman filter paper, #40...resuspended in buffer (15% sucrose, 50 mM Tris pH 7.6, 50 mM EDTA) at 0.2 g filtrate/ml buffer in 15 ml centrifuge tubes. Novozyme was added at 40 mg/ml and

Fuzzy multinomial logistic regression analysis: A multi-objective programming approach

NASA Astrophysics Data System (ADS)

Abdalla, Hesham A.; El-Sayed, Amany A.; Hamed, Ramadan

2017-05-01

Parameter estimation for multinomial logistic regression is usually based on maximizing the likelihood function. For large well-balanced datasets, Maximum Likelihood (ML) estimation is a satisfactory approach. Unfortunately, ML can fail completely or at least produce poor results in terms of estimated probabilities and confidence intervals of parameters, specially for small datasets. In this study, a new approach based on fuzzy concepts is proposed to estimate parameters of the multinomial logistic regression. The study assumes that the parameters of multinomial logistic regression are fuzzy. Based on the extension principle stated by Zadeh and Bárdossy's proposition, a multi-objective programming approach is suggested to estimate these fuzzy parameters. A simulation study is used to evaluate the performance of the new approach versus Maximum likelihood (ML) approach. Results show that the new proposed model outperforms ML in cases of small datasets.

Comparison of Spectra Optia and COBE Spectra apheresis systems' performances for red blood cell exchange procedures.

PubMed

Kim, Jaehyup; Joseph, Ranjit; Matevosyan, Karen; Sarode, Ravi

2016-12-01

Spectra Optia (Terumo BCT, Lakewood, CO) was FDA approved for red blood cell exchange (RBCx) procedures in January 2014 and is expected to replace COBE spectra (Terumo BCT) very soon in the USA. The performance characteristics of these devices for Isovolemic Hemodilution (IHD-RBCx) procedure were compared in this study. A total of 114 IHD-RBCx procedures from 19 patients were analyzed. For every patient, three procedures on each device with similar pre-procedure hematocrits were compared. Pre and post procedure laboratory parameters compared were hemoglobin S (HbS), hematocrits (Hct), platelet counts and fraction of cells remaining (FCR). Statistical analysis was performed using t-test adjusted by the Holm-Bonferroni method to reduce family-wise error rate. There were no significant differences between these two devices in regards to HbS, Hct, FCR and platelet counts (p = > 0.05). However, rinseback volume (124.2 ± 8.9 ml) and normal saline replacement volume during IHD phase (296.1 ± 97.2 ml) were lower in Spectra Optia as compared to COBE Spectra (337 ± 33.8 ml and 326.6 ± 105.2 ml, p value <0.001 and 0.030 respectively). Spectra Optia had a longer run time (107.1 ± 15.9 min vs 123.8 ± 19.6 min, p value <0.001) overall. Performance characteristics of Spectra Optia for HbS, Hct and FCR were similar to COBE Spectra for IHD-RBCx. IHD-RBCx procedure on Optia required less normal saline replacement volume and rinse back volume but with overall longer procedure run time. Copyright © 2016. Published by Elsevier Ltd.

Association between prophylactic oxytocin use during dilation and evacuation and estimated blood loss.

PubMed

Whitehouse, Katherine; Tschann, Mary; Davis, James; Soon, Reni; Salcedo, Jennifer; Friedlander, EmmaKate; Kaneshiro, Bliss

2017-07-01

Some providers use oxytocin during dilation and evacuation (D&E) to prevent or treat hemorrhage, although evidence to support this is scarce. We sought to describe the association between prophylactic oxytocin use, estimated blood loss (EBL), and surgical outcomes during D&E. We performed a chart review of 730 women at 14 to 26 weeks' gestation who had a D&E at our institution between May 2010 and May 2014 to assess the association between prophylactic oxytocin use and EBL. We determined whether sociodemographic and health-related factors were associated with excessive blood loss (EBL≥250 mL) and whether oxytocin use was associated with complications, including hemorrhage (i.e., EBL≥500 mL or interventions for bleeding). We performed univariate analyses and multivariable regression models to evaluate the relationship between health-related factors and EBL≥250 mL. Providers used prophylactic oxytocin in 59.9% of procedures. Asian (p=.005 and Native Hawaiian/Pacific Islander (p=.005) race, nulliparity (p=.007) and higher gestational age (p<.001) were associated with prophylactic oxytocin use. We found no difference in mean EBL (116.2±105.5 mL versus 130.7±125.5 mL, p=.09), EBL≥250 mL (31.4% vs. 68.6%, p=.15) or complications (6.1% vs. 7.1%, p=.73) including hemorrhage (1.4% vs. 5.3%, p=.14) between those who did not receive prophylactic oxytocin and those who did. No transfusions occurred in either group. In multivariable regression modeling, the adjusted OR for excessive blood loss was 0.42 (95% confidence interval 0.16-1.07) with prophylactic oxytocin use. Prophylactic oxytocin use during D&E was not associated with hemorrhage or transfusion in our population. Routine use of interventions for bleeding, such as intravenous oxytocin, should be based on scientific evidence or not performed. Findings from our study provide information on how oxytocin use is associated with blood loss during D&E. Copyright © 2017 Elsevier Inc. All rights reserved.

Variational Bayesian Parameter Estimation Techniques for the General Linear Model

PubMed Central

Starke, Ludger; Ostwald, Dirk

2017-01-01

Variational Bayes (VB), variational maximum likelihood (VML), restricted maximum likelihood (ReML), and maximum likelihood (ML) are cornerstone parametric statistical estimation techniques in the analysis of functional neuroimaging data. However, the theoretical underpinnings of these model parameter estimation techniques are rarely covered in introductory statistical texts. Because of the widespread practical use of VB, VML, ReML, and ML in the neuroimaging community, we reasoned that a theoretical treatment of their relationships and their application in a basic modeling scenario may be helpful for both neuroimaging novices and practitioners alike. In this technical study, we thus revisit the conceptual and formal underpinnings of VB, VML, ReML, and ML and provide a detailed account of their mathematical relationships and implementational details. We further apply VB, VML, ReML, and ML to the general linear model (GLM) with non-spherical error covariance as commonly encountered in the first-level analysis of fMRI data. To this end, we explicitly derive the corresponding free energy objective functions and ensuing iterative algorithms. Finally, in the applied part of our study, we evaluate the parameter and model recovery properties of VB, VML, ReML, and ML, first in an exemplary setting and then in the analysis of experimental fMRI data acquired from a single participant under visual stimulation. PMID:28966572

Maximum Likelihood Estimation of Spectra Information from Multiple Independent Astrophysics Data Sets

NASA Technical Reports Server (NTRS)

Howell, Leonard W., Jr.; Six, N. Frank (Technical Monitor)

2002-01-01

The Maximum Likelihood (ML) statistical theory required to estimate spectra information from an arbitrary number of astrophysics data sets produced by vastly different science instruments is developed in this paper. This theory and its successful implementation will facilitate the interpretation of spectral information from multiple astrophysics missions and thereby permit the derivation of superior spectral information based on the combination of data sets. The procedure is of significant value to both existing data sets and those to be produced by future astrophysics missions consisting of two or more detectors by allowing instrument developers to optimize each detector's design parameters through simulation studies in order to design and build complementary detectors that will maximize the precision with which the science objectives may be obtained. The benefits of this ML theory and its application is measured in terms of the reduction of the statistical errors (standard deviations) of the spectra information using the multiple data sets in concert as compared to the statistical errors of the spectra information when the data sets are considered separately, as well as any biases resulting from poor statistics in one or more of the individual data sets that might be reduced when the data sets are combined.

Multi-parameter comparison of injection laryngoplasty, medialization laryngoplasty, and arytenoid adduction in an excised larynx model

PubMed Central

Hoffman, Matthew R.; Witt, Rachel E.; Chapin, William J.; McCulloch, Timothy M.; Jiang, Jack J.

2010-01-01

Objective Evaluate the effect of injection laryngoplasty (IL), medialization laryngoplasty (ML), and ML combined with arytenoid adduction (ML-AA) on acoustic, aerodynamic, and mucosal wave measurements in an excised larynx setup. Methods Measurements were recorded for eight excised canine larynges with simulated unilateral vocal fold paralysis (UVFP) before and after vocal fold injection with Cymetra. A second set of eight larynges was used to evaluate medialization laryngoplasty using a Silastic implant without and with arytenoid adduction. Results IL and ML led to comparable decreases in phonation threshold flow (PTF), phonation threshold pressure (PTP), and phonation threshold power (PTW). ML-AA led to significant decreases in PTF (p=0.008), PTP (p=0.008), and PTW (p=0.008). IL and ML led to approximately equal decreases in percent jitter and percent shimmer. ML-AA caused the greatest increase in signal to noise ratio (SNR). ML-AA discernibly decreased frequency (p=0.059); a clear trend was not observed for IL or ML. IL significantly reduced mucosal wave amplitude (p=0.002), while both ML and ML-AA increased it. All procedures significantly decreased glottal gap, with the most dramatic effects observed after ML-AA (p=0.004). Conclusions ML-AA led to the greatest improvements in phonatory parameters. IL was comparable to ML aerodynamically and acoustically, but caused detrimental changes to the mucosal wave. Incremental improvements in parameters recorded from the same larynx were observed after ML and ML-AA. To ensure optimal acoustic outcome, the arytenoid must be correctly rotated. This study provides objective support for the combined ML-AA procedure in tolerant patients. Evidence based medicine level Not applicable – animal study. PMID:20213797

SEM with Missing Data and Unknown Population Distributions Using Two-Stage ML: Theory and Its Application

ERIC Educational Resources Information Center

Yuan, Ke-Hai; Lu, Laura

2008-01-01

This article provides the theory and application of the 2-stage maximum likelihood (ML) procedure for structural equation modeling (SEM) with missing data. The validity of this procedure does not require the assumption of a normally distributed population. When the population is normally distributed and all missing data are missing at random…

Emergency Physician Estimation of Blood Loss

PubMed Central

Ashburn, Jeffery C.; Harrison, Tamara; Ham, James J.; Strote, Jared

2012-01-01

Introduction Emergency physicians (EP) frequently estimate blood loss, which can have implications for clinical care. The objectives of this study were to examine EP accuracy in estimating blood loss on different surfaces and compare attending physician and resident performance. Methods A sample of 56 emergency department (ED) physicians (30 attending physicians and 26 residents) were asked to estimate the amount of moulage blood present in 4 scenarios: 500 mL spilled onto an ED cot; 25 mL spilled onto a 10-pack of 4 × 4-inch gauze; 100 mL on a T-shirt; and 150 mL in a commode filled with water. Standard estimate error (the absolute value of (estimated volume − actual volume)/actual volume × 100) was calculated for each estimate. Results The mean standard error for all estimates was 116% with a range of 0% to 1233%. Only 8% of estimates were within 20% of the true value. Estimates were most accurate for the sheet scenario and worst for the commode scenario. Residents and attending physicians did not perform significantly differently (P > 0.05). Conclusion Emergency department physicians do not estimate blood loss well in a variety of scenarios. Such estimates could potentially be misleading if used in clinical decision making. Clinical experience does not appear to improve estimation ability in this limited study. PMID:22942938

Simulation Experiment Description Markup Language (SED-ML) Level 1 Version 2.

PubMed

Bergmann, Frank T; Cooper, Jonathan; Le Novère, Nicolas; Nickerson, David; Waltemath, Dagmar

2015-09-04

The number, size and complexity of computational models of biological systems are growing at an ever increasing pace. It is imperative to build on existing studies by reusing and adapting existing models and parts thereof. The description of the structure of models is not sufficient to enable the reproduction of simulation results. One also needs to describe the procedures the models are subjected to, as recommended by the Minimum Information About a Simulation Experiment (MIASE) guidelines. This document presents Level 1 Version 2 of the Simulation Experiment Description Markup Language (SED-ML), a computer-readable format for encoding simulation and analysis experiments to apply to computational models. SED-ML files are encoded in the Extensible Markup Language (XML) and can be used in conjunction with any XML-based model encoding format, such as CellML or SBML. A SED-ML file includes details of which models to use, how to modify them prior to executing a simulation, which simulation and analysis procedures to apply, which results to extract and how to present them. Level 1 Version 2 extends the format by allowing the encoding of repeated and chained procedures.

Simulation Experiment Description Markup Language (SED-ML) Level 1 Version 2.

PubMed

Bergmann, Frank T; Cooper, Jonathan; Le Novère, Nicolas; Nickerson, David; Waltemath, Dagmar

2015-06-01

The number, size and complexity of computational models of biological systems are growing at an ever increasing pace. It is imperative to build on existing studies by reusing and adapting existing models and parts thereof. The description of the structure of models is not sufficient to enable the reproduction of simulation results. One also needs to describe the procedures the models are subjected to, as recommended by the Minimum Information About a Simulation Experiment (MIASE) guidelines. This document presents Level 1 Version 2 of the Simulation Experiment Description Markup Language (SED-ML), a computer-readable format for encoding simulation and analysis experiments to apply to computational models. SED-ML files are encoded in the Extensible Markup Language (XML) and can be used in conjunction with any XML-based model encoding format, such as CellML or SBML. A SED-ML file includes details of which models to use, how to modify them prior to executing a simulation, which simulation and analysis procedures to apply, which results to extract and how to present them. Level 1 Version 2 extends the format by allowing the encoding of repeated and chained procedures.

Time-resolved speckle effects on the estimation of laser-pulse arrival times

NASA Technical Reports Server (NTRS)

Tsai, B.-M.; Gardner, C. S.

1985-01-01

A maximum-likelihood (ML) estimator of the pulse arrival in laser ranging and altimetry is derived for the case of a pulse distorted by shot noise and time-resolved speckle. The performance of the estimator is evaluated for pulse reflections from flat diffuse targets and compared with the performance of a suboptimal centroid estimator and a suboptimal Bar-David ML estimator derived under the assumption of no speckle. In the large-signal limit the accuracy of the estimator was found to improve as the width of the receiver observational interval increases. The timing performance of the estimator is expected to be highly sensitive to background noise when the received pulse energy is high and the receiver observational interval is large. Finally, in the speckle-limited regime the ML estimator performs considerably better than the suboptimal estimators.

Estimation of channel parameters and background irradiance for free-space optical link.

PubMed

Khatoon, Afsana; Cowley, William G; Letzepis, Nick; Giggenbach, Dirk

2013-05-10

Free-space optical communication can experience severe fading due to optical scintillation in long-range links. Channel estimation is also corrupted by background and electrical noise. Accurate estimation of channel parameters and scintillation index (SI) depends on perfect removal of background irradiance. In this paper, we propose three different methods, the minimum-value (MV), mean-power (MP), and maximum-likelihood (ML) based methods, to remove the background irradiance from channel samples. The MV and MP methods do not require knowledge of the scintillation distribution. While the ML-based method assumes gamma-gamma scintillation, it can be easily modified to accommodate other distributions. Each estimator's performance is compared using simulation data as well as experimental measurements. The estimators' performance are evaluated from low- to high-SI areas using simulation data as well as experimental trials. The MV and MP methods have much lower complexity than the ML-based method. However, the ML-based method shows better SI and background-irradiance estimation performance.

A comparison of the dose of anesthetic agents and the effective interval from the block procedure to skin incision for ultrasound-guided supraclavicular brachial plexus block in upper extremity surgery.

PubMed

Nakayama, Masanori; Sakuma, Yu; Imamura, Hitoshi; Yano, Koichiro; Kodama, Takao; Ikari, Katsunori

2017-12-01

The aim of this study was to review and evaluate the selection and dose of anesthetic agents and the interval from the block procedure to skin incision for supraclavicular brachial plexus block in upper extremity surgery. We reviewed our cases that underwent upper extremity surgery using only ultrasound-guided supraclavicular brachial plexus block in our hospital between 2011 and 2016. Adverse events during surgery were evaluated. Receiver operating characteristic (ROC) curves were constructed to investigate the relationship between the time from the end of the block procedure to skin incision and the use of local anesthesia on the surgical site. There were 255 patients who were divided into three groups according to the anesthetic agents used: group 1, 1% lidocaine (L) 10 ml + 0.75% ropivacaine (R) 20 ml (n = 62); group 2, L 20 ml + R 10 ml (n = 93); and group 3, L 10 ml + R 15 ml (n = 100). The rate of use of local anesthesia on the surgical site was significantly higher in group 3 than in the other two groups. There were no significant differences in the other evaluated items among the three groups. ROC curve analysis indicated that ≥24 min from the end of the block procedure to skin incision might reduce the use of local anesthesia. The total volume of anesthetic agents had an important influence on the rate of the addition of local anesthesia for surgical pain; however, the combined dose of agents did not influence the evaluation items. For effective analgesia, ≥24 min should elapse from the end of the block procedure to skin incision. Copyright © 2017. Published by Elsevier B.V.

Identification of multiple leaks in pipeline: Linearized model, maximum likelihood, and super-resolution localization

NASA Astrophysics Data System (ADS)

Wang, Xun; Ghidaoui, Mohamed S.

2018-07-01

This paper considers the problem of identifying multiple leaks in a water-filled pipeline based on inverse transient wave theory. The analytical solution to this problem involves nonlinear interaction terms between the various leaks. This paper shows analytically and numerically that these nonlinear terms are of the order of the leak sizes to the power two and; thus, negligible. As a result of this simplification, a maximum likelihood (ML) scheme that identifies leak locations and leak sizes separately is formulated and tested. It is found that the ML estimation scheme is highly efficient and robust with respect to noise. In addition, the ML method is a super-resolution leak localization scheme because its resolvable leak distance (approximately 0.15λmin , where λmin is the minimum wavelength) is below the Nyquist-Shannon sampling theorem limit (0.5λmin). Moreover, the Cramér-Rao lower bound (CRLB) is derived and used to show the efficiency of the ML scheme estimates. The variance of the ML estimator approximates the CRLB proving that the ML scheme belongs to class of best unbiased estimator of leak localization methods.

Measurement of free and bound malondialdehyde in plasma by high-performance liquid chromatography as the 2,4-dinitrophenylhydrazine derivative.

PubMed

Pilz, J; Meineke, I; Gleiter, C H

2000-06-09

We established a method for the detection of free and total (free and bound) malondialdehyde (MDA) in human plasma samples after derivatisation with 2,4-dinitrophenylhydrazine (DNPH). Free MDA was prepared by perchloric acid deproteinisation whereas an alkaline hydrolysation step for 30 min at 60 degrees C was introduced prior to protein precipitation for the determination of total MDA. Derivatisation was accomplished in 10 min at room temperature subsequently chromatographed by HPLC on a reversed-phase 3 microm C(18) column with UV detection (310 nm). The detection limit was 25 pmol/ml for free and 0.3 nmol/ml for total MDA. The recovery of MDA added to different human plasma samples was 93.6% (n=11; RSD 7.1%) for the hydrolysation procedure. In samples from 12 healthy volunteers who underwent a hypoxic treatment (13% O2 for 6 h) we estimated a baseline value of total MDA of 2.16 nmol/ml (SD 0.29) (ambient air) with a significant increase to 2.92 (nmol/ml, SD 0.57; P=0.01) after the end of this physiological oxidative stress challenge. Plasma values of free MDA in these samples were close to our detection limit. The presented technique can easily performed with an isocratic HPLC apparatus and provides highly specific results for MDA as do sophisticated GC-MS methods.

Investigation of Procedures for Automatic Resonance Extraction from Noisy Transient Electromagnetics Data. Volume III. Translation of Prony’s Original Paper and Bibliography of Prony’s Method

DTIC Science & Technology

1981-08-17

Van Blaricum, "On the Source of Parameter Bias in Prony’s Method," 1980 NEM Conference, Disneyland Hotel, August 1980. Auton, J.R., "An Unbiased...Method for the Estimation of the SEM Parameters of an Electromagnetic System," 1980 NEM Conference, Disneyland Hotel, August 1980. Auton, J.R. and M.L...34 1980 NEM Conference, Disneyland Hotel, August 5-7, 1980. Chuang, C.W. and D.L. Moffatt, "Complex Natural Responances of Radar Targets via Prony’s

Vortex-assisted emulsification semimicroextraction for the analytical control of restricted ingredients in cosmetic products: determination of bronopol by liquid chromatography.

PubMed

Miralles, Pablo; Bellver, Raquel; Chisvert, Alberto; Salvador, Amparo

2016-03-01

Vortex-assisted emulsification semimicroextraction is proposed as a one-step solution-extraction procedure for sample preparation in cosmetic products. The procedure allows rapid preparation based on dispersion of the sample in a mixture of 1 mL of n-hexane and 0.5 mL of ethanol, followed by the addition of 0.5 mL of water and centrifugation to obtain two separated phases. This procedure provides good sample clean-up with minimum dilution and is very useful for the determination of ingredients with restricted concentrations, such as bronopol. The procedure was applied to the determination of bronopol by liquid chromatography with UV detection. The best chromatographic separation was obtained by using a C18 column set at 40 °C and performing a stepwise elution with a mixture of ethanol/aqueous 1 % acetic acid solution as mobile phase pumped at 0.5 mL min(-1). The detection wavelength was set at 250 nm and the total run time required was 12 min. The method was successfully applied to 18 commercial cosmetic samples including creams, shampoos, and bath gels. Good recoveries and repeatability were obtained, with a limit of detection of 0.9 μg mL(-1), which makes the method suitable for the analytical control of cosmetic products. Moreover, it could be considered environmentally friendly, because water, ethanol, and only a low volume of n-hexane are used as solvents.

Gelatin-thrombin hemostatic matrix in neurosurgical procedures: hemostasis effectiveness and economic value of clinical and surgical procedure-related benefits.

PubMed

Esposito, Felice; Cappabianca, Paolo; Angileri, Filippo F; Cavallo, Luigi M; Priola, Stefano M; Crimi, Salvatore; Solari, Domenico; Germanò, Antonino F; Tomasello, Francesco

2016-07-26

Gelatin-thrombin hemostatic matrix (FloSeal®) use is associated with shorter surgical times and less blood loss, parameters that are highly valued in neurosurgical procedures. We aimed to assess the effectiveness of gelatin-thrombin in neurosurgical procedures and estimate its economic value. In a 6-month retrospective evaluation at 2 hospitals, intraoperative and postoperative information were collected from patients undergoing neurosurgical procedures where bleeding was controlled with gelatin-thrombin matrix or according to local bleeding control guidelines (control group). Study endpoints were: length of surgery, estimated blood loss, hospitalization duration, blood units utilized, intensive care unit days, postoperative complications, and time-to-recovery. Statistical methods compared endpoints between the gelatin-thrombin and control groups and resource utilization costs were estimated. Seventy-eight patients (38 gelatin-thrombin; 40 control) were included. Gelatin-thrombin was associated with a shorter surgery duration than control 166±40 versus 185±55, p=0.0839); a lower estimated blood loss (185±80 versus 250±95ml; p=0.0017); a shorter hospital stay (10±3 versus 13±3 days; p<0.001); fewer intensive care unit days (10 days/3 patients and 20 days/4 patients); and shorter time-to-recovery (3±2.2 versus 4±2.8 weeks; p=0861). Fewer gelatin-thrombin patients experienced postoperative complications (3 minor) than the control group (5 minor; 3 major). No gelatin-thrombin patient required blood transfusion; 5 units were administered in the control group. The cost of gelatin-thrombin (€268.40/unit) was offset by the shorter surgery duration (difference of 19 minutes at €858 per hour) and the economic value of improved the other endpoint outcomes (ie, shorter hospital stay, less blood loss/lack of need for transfusion, fewer intensive care unit days, and complications). Gelatin-thrombin hemostatic matrix use in patients undergoing neurosurgical procedures was associated with better intra- and post-operative parameters than conventional hemostasis methods, with these parameters having substantial economic benefits.

Reduction of C Bonds Proceeds with Retention of Configuration: Stereochemical Investigation of the Heterogeneous Reduction by Dideuterium of (Homohypostrophene)Neopentyl(2-Norbornyl)Platinum(II) Complexes on Platinum Black.

DTIC Science & Technology

1991-04-23

ClIH16: C, 89.12; H, 10.88; Found: C, 88.85; H, 10.90. Synthesis of Grignard Reagents . Neopentylmagnesium chloride. Into a 500-mL round-bottomed flask... Grignard reagent several times using the following procedure. We placed 5.0 g (0.206 mol) of magnesium chips and a magnetic stir bar to a 200-mL round...Norbornylmagnesium bromide. This Grignard reagent was synthesized using a variation on established procedures. 58,60 We transferred under argon 50.0 mL (30.0 mmol

Direct determination of gallium on polyurethane foam by X-ray fluorescence.

PubMed

Carvalho, M S; Medeiros, J A; Nóbrega, A W; Mantovano, J L; Rocha, V P

1995-01-01

Gallium chloride is easily extracted from 6M HCl by comminuted polyether-type polyurethane foam. After the extraction step, the gallium absorbed by the PU foam can be quantitatively determined by X-ray fluorescence. A procedure for the direct determination of gallium absorbed by PU foam by XRFS is thus described. Gallium is determined at levels as low as 60 ng/ml (C(L)), with a calibration sensitivity of 424 cps ml/mug, within a linear range 0.1-2.30 mug/ml. The procedure investigated was successfully applied to determination of gallium in aluminum alloys, bauxite and industrial residue samples.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beavin, P. Jr.

A rapid direct dilution procedure for the estimation of soluble zirconium and a fusion procedure for the determination of total zirconium (soluble and insoluble forms) in cream base concentrates prepared from antiperspirant aerosols are described. The direct dilution procedure involves extraction of soluble zirconium with HCl (55 + 45). The filtered extract is reacted with alizarin red S to form a stable colored complex which is measured spectrophotometrically. The fusion procedure involves ashing the aerosol concentrate followed by fusion of the ash with potassium pyrosulfate to form an acid-soluble melt. Zirconium is precipitated from solution as the hydroxide and washedmore » to eliminate interfering ions, particularly sulfate. After redissolving in HCl (55 + 45) and reacting with alizarin red S, total zirconium is measured. Zirconyl chloride octahydrate, assayed gravimetrically by hydroxide precipitation and conversion to the oxide, is used as the zirconium reference standard. Concentration range of zirconium measured was 200 to 500 ..mu..g/100 ml. Recoveries of standard zirconium added to commercial aerosols labeled to contain aluminum and zirconyl hydroxychlorides ranged from 97 to 101 percent by the fusion procedure. Analysis of these aerosols by direct dilution gave generally slightly lower results than by fusion.« less

Joint Symbol Timing and CFO Estimation for OFDM/OQAM Systems in Multipath Channels

NASA Astrophysics Data System (ADS)

Fusco, Tilde; Petrella, Angelo; Tanda, Mario

2009-12-01

The problem of data-aided synchronization for orthogonal frequency division multiplexing (OFDM) systems based on offset quadrature amplitude modulation (OQAM) in multipath channels is considered. In particular, the joint maximum-likelihood (ML) estimator for carrier-frequency offset (CFO), amplitudes, phases, and delays, exploiting a short known preamble, is derived. The ML estimators for phases and amplitudes are in closed form. Moreover, under the assumption that the CFO is sufficiently small, a closed form approximate ML (AML) CFO estimator is obtained. By exploiting the obtained closed form solutions a cost function whose peaks provide an estimate of the delays is derived. In particular, the symbol timing (i.e., the delay of the first multipath component) is obtained by considering the smallest estimated delay. The performance of the proposed joint AML estimator is assessed via computer simulations and compared with that achieved by the joint AML estimator designed for AWGN channel and that achieved by a previously derived joint estimator for OFDM systems.

Tiletamine-zolazepam, ketamine, and xylazine anesthesia of captive cheetah (Acinonyx jubatus).

PubMed

Lewandowski, Albert H; Bonar, Christopher J; Evans, Sara E

2002-12-01

Thirty-two anesthetic episodes used a combination of tiletamine-zolezepam (50 mg/ml each), ketamine (80 mg/ml), and xylazine (20 mg/ml) at various dosages for routine diagnostic and minor surgical procedures in 13 captive cheetahs (Acinonyx jubatus). The mean dosage (0.023 +/- 0.003 ml/kg) provided rapid induction with a single i.m. injection along with safe predictable working time, good muscle relaxation, and analgesia. Yohimbine administration subsequently accelerated smooth and rapid recovery.

Prospective randomized clinical trial: single and weekly viscosupplementation

PubMed Central

Zóboli, Alejandro Agustin Carri; de Rezende, Márcia Uchôa; de Campos, Gustavo Constantino; Pasqualin, Thiago; Frucchi, Renato; de Camargo, Olavo Pires

2013-01-01

OBJECTIVE: To compare two different dosages of an intermediate molecular weight sodium hyaluronate (HA) (Osteonil®-TRB Pharma) assessing whether a single 6 ml application of this HA has the same effectiveness as the classical three-weekly 2 ml dose. METHODS: 108 patients with knee osteoarthritis were randomized into two groups of 54 patients each. The groups were designated "single" (S) and "weekly" (W). Patients in group S underwent a viscosupplementation procedure by application of only 6 ml of sodium hyaluronate and 1 ml triamcinolone hexacetonide. Patients in group W underwent the procedure of viscosupplementation through three applications with 2 ml sodium hyaluronate with a week interval between them, and the first application was also performed with the infiltration of 1 ml (20 mg) of Triamcinolone Hexacetonide. Both groups were assessed before, at one month and three months after application, by responding to the WOMAC, Lequesne, IKDC and VAS questionnaires. RESULTS: There was no statistical difference between the single application of 6 ml of sodium hyaluronate and classic application with three weekly injections. However, only the classical regime showed statistically significant improvement in baseline pain (WOMAC pain and VAS). CONCLUSION: Our results suggest that both application schemes improve application function, but the three-weekly regimen of 2 ml was more effective in reducing pain. Level of Evidence I, Prospective Randomized, Clinical Trial. PMID:24453681

Robotic hybrid technique in rectal surgery for deep pelvic endometriosis.

PubMed

Cassini, Diletta; Cerullo, Guido; Miccini, Michelangelo; Manoochehri, Farshad; Ercoli, Alfredo; Baldazzi, Gianandrea

2014-02-01

Deep pelvic endometriosis is a complex disorder that affects 6% to 12% of all women in childbearing age. The incidence of bowel endometriosis ranges between 5.3% and 12%, with rectum and sigma being the most frequently involved tracts, accounting for about 80% of cases. It has been reported that segmental colorectal resection is the best surgical option in terms of recurrence rate and improvement of symptoms. The aim of this study is to analyze indications, feasibility, limits, and short-term results of robotic (Da Vinci Surgical System)-assisted laparoscopic rectal sigmoidectomy for the treatment of deep pelvic endometriosis. Between January 2006 and December 2010, 19 women with bowel endometriosis underwent colorectal resection through the robotic-assisted laparoscopic approach. Intraoperative and postoperative data were collected. All procedures were performed in a single center and short-term complications were evaluated. Nineteen robotic-assisted laparoscopic colorectal resections for infiltrating endometriosis were achieved. Additional procedures were performed in 7 patients (37%). No laparotomic conversion was performed. No intraoperative complications were observed. The mean operative time was 370 minutes (range = 250-720 minutes), and the estimated blood loss was 250 mL (range = 50-350 mL). The overall complication rate was 10% (2 rectovaginal fistulae). Deep pelvic endometriosis is a benign condition but may have substantial impact on quality of life due to severe pelvic symptoms. We believe that robotic-assisted laparoscopic colorectal resection is a feasible and relatively safe procedure in the context of close collaboration between gynecologists and surgeons for treatment of deep pelvic endometriosis with intestinal involvement, with low rates of complications and significant improvement of intestinal symptoms.

A Two-Stage Approach to Missing Data: Theory and Application to Auxiliary Variables

ERIC Educational Resources Information Center

Savalei, Victoria; Bentler, Peter M.

2009-01-01

A well-known ad-hoc approach to conducting structural equation modeling with missing data is to obtain a saturated maximum likelihood (ML) estimate of the population covariance matrix and then to use this estimate in the complete data ML fitting function to obtain parameter estimates. This 2-stage (TS) approach is appealing because it minimizes a…

Development of a validated UPLC method for simultaneous estimation of both free and entrapped (in solid lipid nanoparticles) all-trans retinoic acid and cholecalciferol (vitamin D3) and its pharmacokinetic applicability in rats.

PubMed

Kumar, Manoj; Sharma, Gaurav; Singla, Dinesh; Singh, Sukhjeet; Sahwney, Sudhir; Chauhan, Anurag S; Singh, Gagandeep; Kaur, Indu Pal

2014-03-01

A sensitive ultra-performance liquid chromatography (UPLC) method was developed for simultaneous estimation of all-trans retinoic acid (ATRA) and cholecalciferol (vitamin D3) in rat plasma. The method was validated over the linear range of 1.0-5000ng/ml (r(2)=0.999) for both vitamins with a limit of detection of 0.5ng/ml. Chromatographic separation was achieved using liquid-liquid extraction (LLE) on an Acquity BEH RP 18 column (2.1mm×50mm, I.D. 1.7μm), with mobile phase comprising of acetonitrile:methanol:water (90:8:2, v/v/v), at a flow rate of 0.20ml/min and a total run time of 5min. Intra and inter-day variability (RSD) was ≤3.1%, and the accuracy varied between 95.4-99.9% and 95.3-101.1% respectively, for ATRA and 98.5-100.8% and 99.3-101.7%, respectively for vitamin D3. High recovery of ≥96.0% for ATRA and ≥87.80% for vitamin D3 was achieved. ATRA and vitamin D3 were stable in plasma under different storage and processing conditions. The method was applied to estimate the total drug content and entrapment efficiency of ATRA and vitamin D3 loaded solid lipid nanoparticles (SLNs). Concentration of these two agents was determined in rat plasma after simultaneous subcutaneous administration in free form or when loaded into SLNs thus establishing pharmacokinetic application of the developed procedure. Results indicated an improvement in AUC0-∞ by 5.4 times and 29.4 times for ATRA and vitamin D3, respectively, upon their incorporation into SLNs. Simultaneous administration of these two vitamins and their improved and prolonged bioavailability has scope for their use in treatment and control of tuberculosis. Copyright © 2014 Elsevier B.V. All rights reserved.

Robot-assisted partial cystectomy of a bladder pheochromocytoma.

PubMed

Kang, Sung Gu; Kang, Seok Ho; Choi, Hoon; Ko, Young Hwii; Park, Hong Seok; Cheon, Jun

2011-01-01

Pheochromocytoma of the urinary bladder is an unusual tumor that typically presents with hypertensive crises related to micturition. We report here an unusual case of bladder pheochromocytoma that was treated by robotic-assisted laparoscopic partial cystectomy. A 35-year-old male patient presented with headache and hypertension related to micturition. The patient, who had a 3.5 × 4 cm solitary bladder tumor in the bladder dome, underwent robot-assisted partial cystectomy. The whole procedure was successfully performed using the robot without conversion to open surgery. The total operative time was 120 min and the estimated blood loss was 30 ml. Copyright © 2011 S. Karger AG, Basel.

How large is the typical subarachnoid hemorrhage? A review of current neurosurgical knowledge.

PubMed

Whitmore, Robert G; Grant, Ryan A; LeRoux, Peter; El-Falaki, Omar; Stein, Sherman C

2012-01-01

Despite the morbidity and mortality of subarachnoid hemorrhage (SAH), the average volume of a typical hemorrhage is not well defined. Animal models of SAH often do not accurately mimic the human disease process. The purpose of this study is to estimate the average SAH volume, allowing standardization of animal models of the disease. We performed a MEDLINE search of SAH volume and erythrocyte counts in human cerebrospinal fluid as well as for volumes of blood used in animal injection models of SAH, from 1956 to 2010. We polled members of the American Association of Neurological Surgeons (AANS) for estimates of typical SAH volume. Using quantitative data from the literature, we calculated the total volume of SAH as equal to the volume of blood clotted in basal cisterns plus the volume of dispersed blood in cerebrospinal fluid. The results of the AANS poll confirmed our estimates. The human literature yielded 322 publications and animal literature, 237 studies. Four quantitative human studies reported blood clot volumes ranging from 0.2 to 170 mL, with a mean of ∼20 mL. There was only one quantitative study reporting cerebrospinal fluid red blood cell counts from serial lumbar puncture after SAH. Dispersed blood volume ranged from 2.9 to 45.9 mL, and we used the mean of 15 mL for our calculation. Therefore, total volume of SAH equals 35 mL. The AANS poll yielded 176 responses, ranging from 2 to 350 mL, with a mean of 33.9 ± 4.4 mL. Based on our estimate of total SAH volume of 35 mL, animal injection models may now become standardized for more accurate portrayal of the human disease process. Copyright © 2012 Elsevier Inc. All rights reserved.

In Vitro Acquisition of Secondary Azole Resistance in Aspergillus fumigatus Isolates after Prolonged Exposure to Itraconazole: Presence of Heteroresistant Populations

PubMed Central

Escribano, Pilar; Recio, Sandra; Peláez, Teresa; González-Rivera, Milagros; Bouza, Emilio

2012-01-01

Secondary resistance to azoles in Aspergillus fumigatus isolates from patients taking long-term itraconazole therapy has been described. We studied the acquisition of secondary azole resistance in 20 A. fumigatus isolates with no mutations at codon 54, 98, 138, 220, 432, or 448 in the cyp51A gene. Adjusted conidium inocula (3 × 107 CFU/ml) of each isolate were prepared and progressively or directly exposed to increasing itraconazole concentrations, ranging from 0.5 μg/ml to 16 μg/ml. Itraconazole, voriconazole, and posaconazole MICs were determined using the CLSI M38-A2 procedure before (MICinitial) and after (MICfinal) exposure to itraconazole. In both procedures, the MICfinal was significantly higher than the MICinitial. However, after progressive exposure to itraconazole, the MICs of the three azoles were higher than after direct exposure. No mutations were found at codon 54, 98, 138, 220, 432, or 448 in the cyp51A gene of isolates growing at the highest concentration of itraconazole. More concentrated conidium inocula (2 × 109 CFU/ml) plated in itraconazole at 4 μg/ml revealed the presence of heteroresistant populations in two initially wild-type isolates. These isolates became resistant to itraconazole and posaconazole only after use of the concentrated inoculum. These heteroresistant isolates harbored a mutation at codon G54, and the MICs of itraconazole and posaconazole were >16 μg/ml. In all procedures, A. fumigatus short tandem repeat (STRAf) typing was used to demonstrate that the genotype did not change before or after exposure to itraconazole. PMID:22006000

Approximate, computationally efficient online learning in Bayesian spiking neurons.

PubMed

Kuhlmann, Levin; Hauser-Raspe, Michael; Manton, Jonathan H; Grayden, David B; Tapson, Jonathan; van Schaik, André

2014-03-01

Bayesian spiking neurons (BSNs) provide a probabilistic interpretation of how neurons perform inference and learning. Online learning in BSNs typically involves parameter estimation based on maximum-likelihood expectation-maximization (ML-EM) which is computationally slow and limits the potential of studying networks of BSNs. An online learning algorithm, fast learning (FL), is presented that is more computationally efficient than the benchmark ML-EM for a fixed number of time steps as the number of inputs to a BSN increases (e.g., 16.5 times faster run times for 20 inputs). Although ML-EM appears to converge 2.0 to 3.6 times faster than FL, the computational cost of ML-EM means that ML-EM takes longer to simulate to convergence than FL. FL also provides reasonable convergence performance that is robust to initialization of parameter estimates that are far from the true parameter values. However, parameter estimation depends on the range of true parameter values. Nevertheless, for a physiologically meaningful range of parameter values, FL gives very good average estimation accuracy, despite its approximate nature. The FL algorithm therefore provides an efficient tool, complementary to ML-EM, for exploring BSN networks in more detail in order to better understand their biological relevance. Moreover, the simplicity of the FL algorithm means it can be easily implemented in neuromorphic VLSI such that one can take advantage of the energy-efficient spike coding of BSNs.

Interference-free determination of trace copper in freshly ripened honeys by flame atomic absorption spectrometry following a preconcentration by solid-phase extraction and a two-step elution process.

PubMed

Pohl, Pawel; Stecka, Helena; Jamroz, Piotr

2014-02-01

A fast and straightforward procedure aimed at separating copper (Cu) ions from monosacharides and preconcentrating their traces before flame atomic absorption spectrometry (FAAS) measurements was developed, and its suitability was evaluated by the analysis of freshly ripened honeys on the content of this environmentally and physiologically relevant element. This procedure included the passage (at 20 mL/min) of 10 % (m/v) solutions of honeys (100 mL) through resin beds of Dowex 50 W × 8-400 to retain Cu by solid-phase extraction (SPE) and separate it from the glucose and fructose matrix. In turn, SPE columns were rinsed at 20 mL/min with 20 mL of water and subsequently washed with 20 mL of a 0.5 mol/L HNO3 solution (at 2.0 mL/min) to elute potassium and sodium. Preconcentrated Cu was stripped (at 2.0 mL/min) with 5.0 mL of a 2.0 mol/L HCl solution and determined by FAAS. The proposed procedure was used for the analysis of six ripened monoflower and multiflower honeys, enabling the measurement of Cu within the range of 0.17-0.42 μg/g and with a precision of 3-10%. Recoveries of Cu added to respective honey solutions were within 94-102%, proving the good accuracy of this procedure. The detection limit of Cu achieved with this SPE preconcentration/separation procedure and FAAS detection was 3.6 ng/g.

Non-exercise Estimation of V02max Using a Dichotomy of Meeting or Not Meeting DHHS Physical Activity Recommendations

NASA Technical Reports Server (NTRS)

Wier, Larry T.; Jackson, Allen W.; Jackson, Andrew S.

2009-01-01

The physical activity guidelines (PAG) established by the US Dept. of Health and Human Services in 2008 is consistent with a rating of >/= 6 on the 11-point NASA Physical Activity Status Scale (PASS). Wier, et. al. developed non-exercise models for estimating VO2(sub max) from a combination of PASS, age, gender and either waist girth (WG) (R = 0.810, SEE= 4.799 ml/kg/min), %Fat (R = 0. 817, SEE = 4.716 ml/kg/min) or BMI (R = 0.802, SEE = 4.900 ml . kg-1. min -1 ). PURPOSE: to develop non-exercise models to estimate VO2max from age, gender, body composition (WG, %Fat, BMI) and PASS dichotomized at meets or does not meet the PAG (PAG-PASS), and to compare the accuracy of the PAG-PASS models with the models using the 11-point PASS. METHODS: 2417 men and 384 women were measured for VO2max by indirect calorimetry (RER >1.1); age (yr), gender by M = 1, W = 0; WG at the umbilicus; %fat by skin-folds, BMI by weight (kg) divided by height squared (m 2 ) , and PAGPASS by PASS < 6 = 0 and =/> 6 = 1. RESULTS: Three models were developed by multiple regression to estimate VO2(sub max) from age, gender, PAG-PASS and either WG (R = 0.790, SEE=5.019 ml/kg/min), %FAT (R= 0.080, SEE = 4.915 ml/kg/min) or BMI (R = 0.777, SEE = 5.162ml/kg/min). Cross-validation by the PRESS technique confirmed these statistics. Simple correlations between measured VO2(sub max) and estimates from the PAG-PASS models with WG, %Fat and BMI were 0.790, 0.800 and 0.777, minimally different from the correlations obtained with the PASS models (0.810, 0.810, and 0.802). PAG-PASS and PASS model constant errors were also similar: < 1 ml/kg/min for subsamples of age, gender, PASS and for VO2(sub max) between 30 and 50 ml/kg/min (70% of the sample) but > 1 ml/kg/min for VO2(sub max) <30 and >50 ml/kg/min. CONCLUSIONS: Non-exercise models using the combined effects of age, gender, body composition and the dichotomized PAG-PASS provide estimates of VO2(sub max) that are accurate for most adults, and the accuracy of these models are similar to previously published models using the 11-point PASS.

Drinking behaviour and water turnover rates of Antarctic fur seal pups: implications for the estimation of milk intake by isotopic dilution.

PubMed

Lea, Mary-Anne; Bonadonna, Francesco; Hindell, Mark A; Guinet, Christophe; Goldsworthy, Simon D

2002-06-01

The estimation of milk consumption in free-ranging seals using tritium dilution techniques makes the key assumption that the animals drink no pre-formed water during the experimental period. However, frequent observations of unweaned Antarctic fur seal pups drinking water at Iles Kerguelen necessitated the testing of this assumption. We estimated water flux rates of 30 pups (10.7+/-0.3 kg) in four experimental groups by isotopic dilution over 4 days. The groups were: (1) pups held in an open air enclosure without access to water to estimate fasting metabolic water production (MWP); (2) free-ranging pups not administered additional water; (3) pups held in an open air enclosure and given a total of 300 ml of fresh water to verify technique accuracy; and (4) free-ranging pups given 200 ml of fresh water. Pups without access to water exhibited water flux rates (20.5+/-0.8 ml kg(-1)d(-1)), which were significantly lower than those observed for the free-ranging group (33.0+/-1.7 ml kg(-1) d(-1)). Mean estimated pre-formed water intake for the free-ranging experimental groups was 12.6 ml kg(-1) d(-1). Thus, MWP, measured as total water intake during fasting, may be significantly over-estimated in free-ranging Antarctic fur seal pups at Iles Kerguelen and at other sites and subsequently milk intake rates may be underestimated.

The analysis results of EEWS(Earthquake Early Warning System) about Iksan(Ml4.3) and Ulsan(Ml5.0) earthquakes in Korea

NASA Astrophysics Data System (ADS)

Park, J. H.; Chi, H. C.; Lim, I. S.; Seong, Y. J.; Pak, J.

2016-12-01

EEW(Earthquake Early Warning) service to the public has been officially operated by KMA (Korea Meteorological Administration) from 2015 in Korea. For the KMA's official EEW service, KIGAM has adopted ElarmS from UC Berkeley BSL and modified local magnitude relation, 1-D travel time curves and association procedures with real time waveforms from about 160 seismic stations of KMA and KIGAM. We have checked the performance of EEWS(Earthquake Early Warning System) reviewing two moderate size earthquakes: one is Iksan Eq.(Ml4.3) inside of networks and the other is Ulsan Eq.(Ml5.0) happened at the southern east sea of Korea outside of networks. The first trigger time at NPR station of the Iksan Eq. took 2.3 sec and BUY and JEO2 stations were associated to produce the first event version in 10.07 sec from the origin time respectively. Because the epicentral distance of JEO2 station is about 30 km and the estimated travel time is 6.2 sec, the delay time including transmission and processing is estimated as 3.87 sec with assumption that P wave velocity is 5 km/sec and the focal depth is 8 km. The first magnitude was M4.9 which was a little bigger than Ml4.3 by KIGAM. After adding 3 more triggers of stations (CHO, KMSA, PORA), the estimated magnitude became to M4.6 and the final was settled down to M4.3 with 10 stations. In the case of Ulsan the first trigger time took 11.04 sec and the first alert time with 3 stations in 14.8 sec from the origin time (OT) respectively. The first magnitude was M5.2, however, the difference between the first EEW epicenter and the manual final result was about 63 km due to the poor azimuth coverage outside of seismic network. After 16.2 sec from OT the fourth station YSB was used to update the location near to the manual results within 6 km with magnitude 5.0 and location and magnitude were stable with more stations. Ulsan Eq. was the first case announced to the public by EEWS and the process and result were successful, however, we have to make more effort to reduce the delay times and improve tools for the communication with the public in Korea.

Combustion Product Evaluation of Various Charge Sizes and Propellant Formulations. Task 1 Report: Sampling and Analytical Procedures Proposed for Use in Gun Propellant Combustion Product Characterization

DTIC Science & Technology

1988-01-01

ml, 0.01N, NaOH + 1 ml 30% H202 H2S 10 ml. 0.01M CdSO4 + STRactan 10 in H2 Aldehydes 10 ml of 3.1 WM/ml 2.4- dinitrophenylhydrazine (DNPH) soln. in...3 15 IITRI C06673-TR1 I,ý 3. 3.1.2.6 Aldehydes I After sampling, the 11 flasks will be injected with 10 mi of a 3.1 14/mX -2,4- dinitrophenylhydrazine

A Parameter Estimation Scheme for Multiscale Kalman Smoother (MKS) Algorithm Used in Precipitation Data Fusion

NASA Technical Reports Server (NTRS)

Wang, Shugong; Liang, Xu

2013-01-01

A new approach is presented in this paper to effectively obtain parameter estimations for the Multiscale Kalman Smoother (MKS) algorithm. This new approach has demonstrated promising potentials in deriving better data products based on data of different spatial scales and precisions. Our new approach employs a multi-objective (MO) parameter estimation scheme (called MO scheme hereafter), rather than using the conventional maximum likelihood scheme (called ML scheme) to estimate the MKS parameters. Unlike the ML scheme, the MO scheme is not simply built on strict statistical assumptions related to prediction errors and observation errors, rather, it directly associates the fused data of multiple scales with multiple objective functions in searching best parameter estimations for MKS through optimization. In the MO scheme, objective functions are defined to facilitate consistency among the fused data at multiscales and the input data at their original scales in terms of spatial patterns and magnitudes. The new approach is evaluated through a Monte Carlo experiment and a series of comparison analyses using synthetic precipitation data. Our results show that the MKS fused precipitation performs better using the MO scheme than that using the ML scheme. Particularly, improvements are significant compared to that using the ML scheme for the fused precipitation associated with fine spatial resolutions. This is mainly due to having more criteria and constraints involved in the MO scheme than those included in the ML scheme. The weakness of the original ML scheme that blindly puts more weights onto the data associated with finer resolutions is overcome in our new approach.

Appropriate interpretation of aerobic capacity: allometric scaling in adult and young soccer players

PubMed Central

Chamari, K; Moussa-Chamari, I; Boussaidi, L; Hachana, Y; Kaouech, F; Wisloff, U

2005-01-01

Objective: To compare aerobic capacity of young and adult elite soccer players using appropriate scaling procedures. Methods: Twenty four male adult (mean (SD) age 24 (2) years, weight 75.7 (7.2) kg, VO2MAX 66.6 (5.2) ml/lbm/min, where lbm is lean body mass in kg) and 21 youth (14 (0.4) years, 60.2 (7.3) kg, 66.5 (5.9) ml/lbm/min) elite soccer players took part in the study. Allometric equations were used to determine the relation between maximal and submaximal oxygen cost of running (running economy) and body mass. Results: Maximal and submaximal oxygen uptake increased in proportion to body mass raised to the power of 0.72 (0.04) and 0.60 (0.06) respectively. The VO2MAX of adult players was similar to that of the youth players when expressed in direct proportion to body mass—that is, ml/kg/min—but 5% higher (p<0.05) when expressed using appropriate procedures for scaling. Conversely, compared with seniors, youth players had 13% higher (p<0.001) energy cost of running—that is, poorer running economy—when expressed as ml/kg/min but not when expressed according to the scaling procedures. Conclusions: Compared with the youth soccer players, VO2MAX in the seniors was underestimated and running economy overestimated when expressed traditionally as ml/lbm/min. The study clearly shows the pitfalls in previous studies when aerobic capacity was evaluated in subjects with different body mass. It further shows that the use of scaling procedures can affect the evaluation of, and the resultant training programme to improve, aerobic capacity. PMID:15665205

[Robotic assisted laparoscopy: comparison of segmentary colorectal resection and shaving for colorectal endometriosis].

PubMed

Diguisto, C; Hébert, T; Paternotte, J; Kellal, I; Marret, H; Ouldamer, L; Body, G

2015-04-01

To compare perioperative complications of two surgical methods for digestive endometriosis management: "shaving" and colorectal resection in robotic-assisted laparoscopy. Twenty-eight women underwent robotic-assisted laparoscopy for digestive endometriosis, confirmed histologically. Six women had a digestive resection and twenty-one women had a shaving procedure. Short-term and long-term results and complications were compared between the two groups. Operative time was significantly shorter (P=0.0002) and estimated blood loss was significantly lower (200 ml vs 560 ml, P=0.04) in the shaving procedure group in comparison with the resection group. We observed one conversion to laparotomy in the resection group and one case of bladder injury in the shaving group. Length of hospital stay was longer (P=0.0001) in the resection group than in the shaving group. At the two-month re-evaluation, there was no significant difference between the two groups for the number of women in full remission for pelvic pain, urinary or gastrointestinal symptoms or dyspareunia. Two women of the resection group reported functional gastrointestinal signs that persisted 24 months after the intervention. Both immediate and delayed operative morbidity are more frequent in case of resection. Surgery for deep infiltrating endometriosis, even if operated with robotic assisted laparoscopy, is associated with significant morbidity. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Fitting power-laws in empirical data with estimators that work for all exponents

PubMed Central

Hanel, Rudolf; Corominas-Murtra, Bernat; Liu, Bo; Thurner, Stefan

2017-01-01

Most standard methods based on maximum likelihood (ML) estimates of power-law exponents can only be reliably used to identify exponents smaller than minus one. The argument that power laws are otherwise not normalizable, depends on the underlying sample space the data is drawn from, and is true only for sample spaces that are unbounded from above. Power-laws obtained from bounded sample spaces (as is the case for practically all data related problems) are always free of such limitations and maximum likelihood estimates can be obtained for arbitrary powers without restrictions. Here we first derive the appropriate ML estimator for arbitrary exponents of power-law distributions on bounded discrete sample spaces. We then show that an almost identical estimator also works perfectly for continuous data. We implemented this ML estimator and discuss its performance with previous attempts. We present a general recipe of how to use these estimators and present the associated computer codes. PMID:28245249

Using an EM Covariance Matrix to Estimate Structural Equation Models with Missing Data: Choosing an Adjusted Sample Size to Improve the Accuracy of Inferences

ERIC Educational Resources Information Center

Enders, Craig K.; Peugh, James L.

2004-01-01

Two methods, direct maximum likelihood (ML) and the expectation maximization (EM) algorithm, can be used to obtain ML parameter estimates for structural equation models with missing data (MD). Although the 2 methods frequently produce identical parameter estimates, it may be easier to satisfy missing at random assumptions using EM. However, no…

Enzymatic assay for calmodulins based on plant NAD kinase activity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harmon, A.C.; Jarrett, H.W.; Cormier, M.J.

NAD kinase with increased sensitivity to calmodulin was purified from pea seedlings (Pisum sativum L., Willet Wonder). Assays for calmodulin based on the activities of NAD kinase, bovine brain cyclic nucleotide phosphodiesterase, and human erythrocyte Ca/sup 2 -/-ATPase were compared for their sensitivities to calmodulin and for their abilities to discriminate between calmodulins from different sources. The activities of the three enzymes were determined in the presence of various concentrations of calmodulins from human erythrocyte, bovine brain, sea pansy (Renilla reniformis), mung bean seed (Vigna radiata L. Wilczek), mushroom (Agaricus bisporus), and Tetrahymena pyriformis. The concentrations of calmodulin required formore » 50% activation of the NAD kinase (K/sub 0.5/) ranged from 0.520 ng/ml for Tetrahymena to 2.20 ng/ml for bovine brain. The A/sub 0.5/ s ranged from 19.6 ng/ml for bovine brain calmodulin to 73.5 ng/ml for mushroom calmodulin for phosphodiesterase activation. The K/sub 0.5/'s for the activation of Ca/sup 2 +/-ATPase ranged from 36.3 ng/mol for erythrocyte calmodulin to 61.7 ng/ml for mushroom calmodulin. NAD kinase was not stimulated by phosphatidylcholine, phosphatidylserine, cardiolipin, or palmitoleic acid in the absence or presence of Ca/sup 2 +/. Palmitic acid had a slightly stimulatory effect in the presence of Ca/sup 2 +/ (10% of maximum), but no effect in the absence of Ca/sup 2 +/. Palmitoleic acid inhibited the calmodulin-stimulated activity by 50%. Both the NAD kinase assay and radioimmunoassay were able to detect calmodulin in extracts containing low concentrations of calmodulin. Estimates of calmodulin contents of crude homogenates determined by the NAD kinase assay were consistent with amounts obtained by various purification procedures. 30 references, 1 figure, 4 tables.« less

Ultra-high performance liquid chromatography tandem mass spectrometric method for the determination of tamoxifen, N-desmethyltamoxifen, 4-hydroxytamoxifen and endoxifen in dried blood spots--development, validation and clinical application during breast cancer adjuvant therapy.

PubMed

Antunes, Marina Venzon; Raymundo, Suziane; de Oliveira, Vanessa; Staudt, Dilana Elisabeth; Gössling, Gustavo; Peteffi, Giovana Piva; Biazús, Jorge Villanova; Cavalheiro, José Antônio; Tre-Hardy, Marie; Capron, Arnaud; Haufroid, Vincent; Wallemacq, Pierre; Schwartsmann, Gilberto; Linden, Rafael

2015-01-01

A LC-MSMS method for the simultaneous determination of tamoxifen, N-desmethyltamoxifen, 4-hydroxytamoxifen and endoxifen in dried blood spots samples was developed and validated. The method employs an ultrasound-assisted liquid extraction and a reversed phase separation in an Acquity(®) C18 column (150×2.1 mm, 1.7 µm). Mobile phase was a mixture of formic acid 0.1% (v/v) pH 2.7 and acetonitrile (gradient from 60:40 to 50:50, v/v). Total analytical run time was 8 min. Precision assays showed CV % lower than 10.75% and accuracy in the range 94.5 to 110.3%. Mean analytes recoveries from DBS ranged from 40% to 92%. The method was successfully applied to 91 paired clinical DBS and plasma samples. Dried blood spots concentrations were highly correlated to plasma, with rs>0.83 (P<0.01). Median estimated plasma concentrations after hematocrit and partition factor adjustment were: TAM 123.3 ng mL(-1); NDT 267.9 ng mL(-1), EDF 10.0 ng mL(-1) and HTF 1.3 ng mL(-1,) representing in average 98 to 104% of the actually measured concentrations. The DBS method was able to identify 96% of patients with plasma EDF concentrations below the clinical threshold related to better prognosis (5.9 ng mL(-1)). The procedure has adequate analytical performance and can be an efficient tool to optimize adjuvant breast cancer treatment, especially in resource limited settings. Copyright © 2014 Elsevier B.V. All rights reserved.

On the uncertainty in single molecule fluorescent lifetime and energy emission measurements

NASA Technical Reports Server (NTRS)

Brown, Emery N.; Zhang, Zhenhua; Mccollom, Alex D.

1995-01-01

Time-correlated single photon counting has recently been combined with mode-locked picosecond pulsed excitation to measure the fluorescent lifetimes and energy emissions of single molecules in a flow stream. Maximum likelihood (ML) and least square methods agree and are optimal when the number of detected photons is large however, in single molecule fluorescence experiments the number of detected photons can be less than 20, 67% of those can be noise and the detection time is restricted to 10 nanoseconds. Under the assumption that the photon signal and background noise are two independent inhomogeneous poisson processes, we derive the exact joint arrival time probably density of the photons collected in a single counting experiment performed in the presence of background noise. The model obviates the need to bin experimental data for analysis, and makes it possible to analyze formally the effect of background noise on the photon detection experiment using both ML or Bayesian methods. For both methods we derive the joint and marginal probability densities of the fluorescent lifetime and fluorescent emission. the ML and Bayesian methods are compared in an analysis of simulated single molecule fluorescence experiments of Rhodamine 110 using different combinations of expected background nose and expected fluorescence emission. While both the ML or Bayesian procedures perform well for analyzing fluorescence emissions, the Bayesian methods provide more realistic measures of uncertainty in the fluorescent lifetimes. The Bayesian methods would be especially useful for measuring uncertainty in fluorescent lifetime estimates in current single molecule flow stream experiments where the expected fluorescence emission is low. Both the ML and Bayesian algorithms can be automated for applications in molecular biology.

On the Uncertainty in Single Molecule Fluorescent Lifetime and Energy Emission Measurements

NASA Technical Reports Server (NTRS)

Brown, Emery N.; Zhang, Zhenhua; McCollom, Alex D.

1996-01-01

Time-correlated single photon counting has recently been combined with mode-locked picosecond pulsed excitation to measure the fluorescent lifetimes and energy emissions of single molecules in a flow stream. Maximum likelihood (ML) and least squares methods agree and are optimal when the number of detected photons is large, however, in single molecule fluorescence experiments the number of detected photons can be less than 20, 67 percent of those can be noise, and the detection time is restricted to 10 nanoseconds. Under the assumption that the photon signal and background noise are two independent inhomogeneous Poisson processes, we derive the exact joint arrival time probability density of the photons collected in a single counting experiment performed in the presence of background noise. The model obviates the need to bin experimental data for analysis, and makes it possible to analyze formally the effect of background noise on the photon detection experiment using both ML or Bayesian methods. For both methods we derive the joint and marginal probability densities of the fluorescent lifetime and fluorescent emission. The ML and Bayesian methods are compared in an analysis of simulated single molecule fluorescence experiments of Rhodamine 110 using different combinations of expected background noise and expected fluorescence emission. While both the ML or Bayesian procedures perform well for analyzing fluorescence emissions, the Bayesian methods provide more realistic measures of uncertainty in the fluorescent lifetimes. The Bayesian methods would be especially useful for measuring uncertainty in fluorescent lifetime estimates in current single molecule flow stream experiments where the expected fluorescence emission is low. Both the ML and Bayesian algorithms can be automated for applications in molecular biology.

[Clinical studies on regulatory system of thyroid hormone secretion and serum triiodothyronine. Part. I. Solid-state radioimmunoassy for human serum TSH and its clinical application (author's transl)].

PubMed

Takeda, Y

1975-01-20

A solid-state RIA method using a plastic microtiter plate for human TSH was developed: 1) The choice of carrier protein for standard TSH was critical in this method and pooled sera from untreated Graves patients was found to be suitable for this purpose. The mean lowest detectable TSH level was 0.2 muU/assay, which was almost equal to those reported by other methods. This method is superior in simple assay procedure, especially in the separation of bound and free TSH and in the shorter incubation time required in the double antibody method. 2) Serum TSH concentration in 22 normal subjects, 17 patients with Graves' disease, 35 Hashimoto's thyroiditis, 18 primary hypothyrodism, 16 simple goiter, 4 nodular goiter and 7 secondary hypothyroidism was estimated as 4.7 +/- 2.0 muU/ml (mean +/- s.d.), 2.1 +/- 0.2 mu/U/ml, 14.1 +/- 26.5 muU/ml, 211 +/- 177 muU/ml, 3.6 +/- 2.4 muU/ml, 3.2 +/- 2.4 muU/ml and 2.6 +/- 1.0 muU/ml, respectively. 3) A statistically significant and hyperbolic inverse correlation (r= --0.37, N=90) was found between TSH and T4 levels. Some cases with normal T4 level were found to be high in TSH levels. It was also noted that 36 of 65 euthyroid cases (55.4%) who had been treated with 131I for Graves' disease showed elevated TSH levels. 4) After intravenous injection of 500 mug TRH, TSH level reached its peak value of 8 to 32 muU/ml at 15 to 45 minutes in normal subjects. Low to no response was found in patients with Graves' disease. An exaggerated response in patients with primary hypothyroidism to TRH was observed and an inhibitory process in TSH production at the pituitary level was suggested in patients with Cushing syndrome. Hypothyroid patients with pituitary lesion showed low or no response, on the other hand some hypothyroid patients with lesions around the pituitary and hypothalamus showed high basal TSH and exaggerated response to TRH.

9 CFR 147.15 - Laboratory procedure recommended for the bacteriological examination of mycoplasma reactors. 12

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10523. (5) Use sterile deionized distilled water to reconstitute penicillin. (6) Sterile serum should be... samples (ml)—5.0 (1:2000) Mycoplasma Broth Base (g)—22.5 Aqueous penicillin (units)—500,000 Sterile serum... Aqueous penicillin (units)—400,000 NAD (ml)—12.5 Cysteine hydrochloride (ml)—12.5 (1) Rotate flask gently...

9 CFR 147.15 - Laboratory procedure recommended for the bacteriological examination of mycoplasma reactors. 12

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10523. (5) Use sterile deionized distilled water to reconstitute penicillin. (6) Sterile serum should be... samples (ml)—5.0 (1:2000) Mycoplasma Broth Base (g)—22.5 Aqueous penicillin (units)—500,000 Sterile serum... Aqueous penicillin (units)—400,000 NAD (ml)—12.5 Cysteine hydrochloride (ml)—12.5 (1) Rotate flask gently...

9 CFR 147.15 - Laboratory procedure recommended for the bacteriological examination of mycoplasma reactors. 12

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10523. (5) Use sterile deionized distilled water to reconstitute penicillin. (6) Sterile serum should be... samples (ml)—5.0 (1:2000) Mycoplasma Broth Base (g)—22.5 Aqueous penicillin (units)—500,000 Sterile serum... Aqueous penicillin (units)—400,000 NAD (ml)—12.5 Cysteine hydrochloride (ml)—12.5 (1) Rotate flask gently...

A comparison of practical assessment methods to determine treadmill, cycle and elliptical ergometer VO2peak

PubMed Central

Mays, Ryan J.; Boér, Nicholas F.; Mealey, Lisa M.; Kim, Kevin H.; Goss, Fredric L.

2015-01-01

This investigation compared estimated and predicted peak oxygen consumption (VO2peak) and maximal heart rate (HRmax) among the treadmill, cycle ergometer and elliptical ergometer. Seventeen women (mean ± SE: 21.9 ± .3 yrs) exercised to exhaustion on all modalities. ACSM metabolic equations were used to estimate VO2peak. Digital displays on the elliptical ergometer were used to estimate VO2peak. Two individual linear regression methods were used to predict VO2peak: 1) two steady state heart rate (HR) responses up to 85% of age-predicted HRmax, and 2) multiple steady state/non-steady state HR responses up to 85% of age-predicted HRmax. Estimated VO2peak for the treadmill (46.3 ± 1.3 ml · kg−1 · min−1) and the elliptical ergometer (44.4 ± 1.0 ml · kg−1 · min−1) did not differ. The cycle ergometer estimated VO2peak (36.5 ± 1.0 ml · kg−1 · min−1) was lower (p < .001) than the estimated VO2peak values for the treadmill and elliptical ergometer. Elliptical ergometer VO2peak predicted from steady state (51.4 ± .8 ml · kg−1 · min−1) and steady state/non-steady state (50.3 ± 2.0 ml · kg−1 · min−1) models were higher than estimated elliptical ergometer VO2peak, p < .01. HRmax and estimates of VO2peak were similar between the treadmill and elliptical ergometer, thus cross-modal exercise prescriptions may be generated. The use of digital display estimates of submaximal oxygen uptake for the elliptical ergometer may not be an accurate method for predicting VO2peak. Health-fitness professionals should use caution when utilizing submaximal elliptical ergometer digital display estimates to predict VO2peak. PMID:20393357

Effect of Tranexamic Acid on Blood Loss, D-Dimer, and Fibrinogen Kinetics in Adult Spinal Deformity Surgery.

PubMed

Pong, Ryan P; Leveque, Jean-Christophe A; Edwards, Alicia; Yanamadala, Vijay; Wright, Anna K; Herodes, Megan; Sethi, Rajiv K

2018-05-02

Antifibrinolytics such as tranexamic acid reduce operative blood loss and blood product transfusion requirements in patients undergoing surgical correction of scoliosis. The factors involved in the unrelenting coagulopathy seen in scoliosis surgery are not well understood. One potential contributor is activation of the fibrinolytic system during a surgical procedure, likely related to clot dissolution and consumption of fibrinogen. The addition of tranexamic acid during a surgical procedure may mitigate the coagulopathy by impeding the derangement in D-dimer and fibrinogen kinetics. We retrospectively studied consecutive patients who had undergone surgical correction of adult spinal deformity between January 2010 and July 2016 at our institution. Intraoperative hemostatic data, surgical time, estimated blood loss, and transfusion records were analyzed for patients before and after the addition of tranexamic acid to our protocol. Each patient who received tranexamic acid and met inclusion criteria was cohort-matched with a patient who underwent a surgical procedure without tranexamic acid administration. There were 17 patients in the tranexamic acid cohort, with a mean age of 60.7 years, and 17 patients in the control cohort, with a mean age of 60.9 years. Estimated blood loss (932 ± 539 mL compared with 1,800 ± 1,029 mL; p = 0.005) and packed red blood-cell transfusions (1.5 ± 1.6 units compared with 4.0 ± 2.1 units; p = 0.001) were significantly lower in the tranexamic acid cohort. In all single-stage surgical procedures that met inclusion criteria, the rise of D-dimer was attenuated from 8.3 ± 5.0 μg/mL in the control cohort to 3.3 ± 3.2 μg/mL for the tranexamic acid cohort (p < 0.001). The consumption of fibrinogen was 98.4 ± 42.6 mg/dL in the control cohort but was reduced in the tranexamic acid cohort to 60.6 ± 35.1 mg/dL (p = 0.004). In patients undergoing spinal surgery, intravenous administration of tranexamic acid is effective at reducing intraoperative blood loss. Monitoring of D-dimer and fibrinogen during spinal surgery suggests that tranexamic acid impedes the fibrinolytic pathway by decreasing consumption of fibrinogen and clot dissolution as evidenced by the reduced formation of D-dimer. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

A PILOT STUDY TO DETERMINE THE WATER VOLUME INJESTED BY RECREATIONAL SWIMMERS

EPA Science Inventory

The volume of water ingested by recreational swimmers is unknown. Previous estimates by a number of investigators range from 10mL to 100mL. These estimates, however, are unsupported by empirical data. Many outdoor swimming pools are disinfected using cyanuric acid stabilized c...

Effect of immersion on lung capacities and volumes: implications for the densitometric estimation of relative body fat.

PubMed

Withers, R T; Hamdorf, P A

1989-01-01

Immersion of 18 male subjects in water caused a 20.4% (787 ml) increase (P less than 0.05) in the mean inspiratory capacity (IC) whereas there were no changes (P greater than 0.05) in tidal volume (VT) and the frequency of respiration. All the means for the other pulmonary variables decreased (P less than 0.05) by varying amounts: total lung capacity (TLC) = 8.4% (599 ml), vital capacity (VC) = 5.5% (308 ml), functional residual capacity (FRC) = 42.6% (1386 ml), expiratory reserve volume (ERV) = 61.9% (1095 ml) and residual volume (RV) = 19.7% (292 ml). Variation of only the RV in the body density (BD) formula from which the percentage body fat (%BF) is estimated resulted in a significantly (P less than 0.05) lower mean of 15.2% BF for the RV in air (means = 1482 ml) compared with that of 17.1% BF for the RV in water (means = 1190 ml). All but one of the subjects exhibited a smaller RV in water than in air; the six largest differences were equivalent to 2.4-5.1% BF. These results indicate that the net effect of the hydrostatic pressure (decreases RV), pulmonary vascular engorgement (decreases RV) and diminished compliance (increases RV) is to reduce the ventilated RV. It is therefore advisable to measure the RV when the subject is immersed in order to minimize error in the determination of BD and hence the estimation of % BF.

Anti-hemorrhagic effect of prophylactic tranexamic acid in benign hysterectomy-a double-blinded randomized placebo-controlled trial.

PubMed

Topsoee, Märta Fink; Bergholt, Thomas; Ravn, Pernille; Schouenborg, Lars; Moeller, Charlotte; Ottesen, Bent; Settnes, Annette

2016-07-01

Hysterectomy is one of the most frequently performed major gynecological surgical procedures. Even when the indication for the procedure is benign, relatively high complication rates have been reported. Perioperative bleeding seems to represent the most common cause of complications and in 2004, 8% of all women in Denmark undergoing benign hysterectomy experienced a bleeding complication. Tranexamic acid is an antifibrinolytic agent that has shown to effectively reduce bleeding complications within other surgical and medical areas. However, knowledge about the drug's effect in relation to benign hysterectomy is still missing. To investigate the antihemorrhagic effect of prophylactic tranexamic acid in elective benign hysterectomy. A double-blinded randomized placebo-controlled trial was conducted at 4 gynecological departments in Denmark from April 2013 to October 2014. A total of 332 women undergoing benign abdominal, laparoscopic, or vaginal hysterectomy were included in the trial, randomized to either 1 g of intravenous tranexamic acid or placebo at start of surgery. Chi-square test and Student t test statistical analyses were applied. The primary outcome of intraoperative total blood loss was reduced in the group treated with tranexamic acid compared to the placebo group when estimated both subjectively by the surgeon and objectively by weight (98.4 mL vs 134.8 mL, P = .006 and 100.0 mL vs 166.0 mL, P = .004). The incidence of blood loss ≥500 mL was also significantly reduced (6 vs 21, P = .003), as well as the use of open-label tranexamic acid (7 vs 18, P = .024). Furthermore, the risk of reoperations owing to postoperative hemorrhage was significantly reduced in the tranexamic acid group compared to the placebo group (2 vs 9, P = .034). This corresponds to an absolute risk reduction of 4.2% and number needed to treat of 24. No incidence of thromboembolic events or death was observed in any of the groups. The results support the hypothesis that prophylactic treatment with tranexamic acid reduces the overall total blood loss, the incidence of substantial blood loss, and the need for reoperations owing to postoperative hemorrhage in relation to benign hysterectomy. No incidences of serious adverse events occurred. Thus, tranexamic acid should be considered as a prophylactic treatment prior to elective benign hysterectomy. Copyright © 2016 Elsevier Inc. All rights reserved.

A new method for placental/cord blood processing in the collection bag. I. Analysis of factors involved in red blood cell removal.

PubMed

Bertolini, F; Battaglia, M; Zibera, C; Baroni, G; Soro, V; Perotti, C; Salvaneschi, L; Robustelli della Cuna, G

1996-10-01

We describe a new procedure for large-scale CB processing in the collection bag, thus minimizing the risk of CB contamination. A solution of 6% hydroxyethyl starch (HES) was added directly to the CB containing bag. After RBC sedimentation at 4 degrees C, the WBC-rich supernatant was collected in a satellite bag and centrifuged. After supernatant removal, the cell pellet was resuspended and the percent recovery of total WBC, CD34+ progenitor cells, CFU-GM and cobblestone area-forming cells (CAFC) evaluated. Results obtained with three different types of CB collection bags (300, 600 and 1000 ml) were analyzed and compared with those of an open system in 50 ml tubes. CB processing procedures in 300 and 1000 ml bags were associated with better WBC, CFU, CD34+ cell and CAFC recovery (83-93%). This novel CB processing procedure appears to be easy, effective and particularly suitable for large-scale banking under GMP conditions.

Using the Estimating Supplies Program to Develop Materiel Solutions for the U.S. Air Force Aeromedical Evacuation In-Flight Kit (FFQDM)

DTIC Science & Technology

2008-07-07

Ibuprofen 800-mg tablet. Because of several negative side effects, Chlorpromazine HCL INJ can be replaced with Haloperidol HCL INJ or Promethazine HCL...CART 10S EA 6505013548591 FLUMAZENIL INJ 0.1MG/ML 10ML VI 10S VI 6505002688530 HALOPERIDOL INJ 5MG/ML 1ML AMPUL 10S AM 6505001538480 HYDROGEN...DIAZEPAM TAB 5MG INDIVIDUALLY SEALED 100S TB 6505013548591 FLUMAZENIL INJ 0.1MG/ML 10ML VI 10S VI 6505002688530 HALOPERIDOL INJ 5MG/ML 1ML AMP 10S AM

Serial changes in anatomy and ventricular function on dual-source cardiac computed tomography after the Norwood procedure for hypoplastic left heart syndrome.

PubMed

Goo, Hyun Woo

2017-12-01

Accurate evaluation of anatomy and ventricular function after the Norwood procedure in hypoplastic left heart syndrome is important for treatment planning and prognostication, but echocardiography and cardiac MRI have limitations. To assess serial changes in anatomy and ventricular function on dual-source cardiac CT after the Norwood procedure for hypoplastic left heart syndrome. In 14 consecutive patients with hypoplastic left heart syndrome, end-systolic and end-diastolic phase cardiac dual-source CT was performed before and early (average: 1 month) after the Norwood procedure, and repeated late (median: 4.5 months) after the Norwood procedure in six patients. Ventricular functional parameters and indexed morphological measurements including pulmonary artery size, right ventricular free wall thickness, and ascending aorta size on cardiac CT were compared between different time points. Moreover, morphological features including ventricular septal defect, endocardial fibroelastosis and coronary ventricular communication were evaluated on cardiac CT. Right ventricular function and volumes remained unchanged (indexed end-systolic and end-diastolic volumes: 38.9±14.0 vs. 41.1±21.5 ml/m 2 , P=0.7 and 99.5±30.5 vs. 105.1±33.0 ml/m 2 , P=0.6; ejection fraction: 60.1±7.3 vs. 63.8±7.0%, P=0.1, and indexed stroke volume: 60.7±18.0 vs. 64.0±15.6 ml/m 2 , P=0.5) early after the Norwood procedure, but function was decreased (ejection fraction: 64.2±2.6 vs. 58.1±7.1%, P=0.01) and volume was increased (indexed end-systolic and end-diastolic volumes: 39.2±14.9 vs. 68.9±20.6 ml/m 2 , P<0.003 and 107.8±36.5 vs. 162.9±36.2 ml/m 2 , P<0.006, and indexed stroke volume: 68.6±21.7 vs. 94.0±21.3 ml/m 2 , P=0.02) later. Branch pulmonary artery size showed a gradual decrease without asymmetry after the Norwood procedure. Right and left pulmonary artery stenoses were identified in 21.4% (3/14) of the patients. Indexed right ventricular free wall thickness showed a significant increase early after the Norwood procedure (25.5±3.5 vs. 34.8±5.1 mm/m 2 , P=0.01) and then a significant decrease late after the Norwood procedure (34.8±5.1 vs. 27.2±4.2 mm/m 2 , P<0.0001). The hypoplastic ascending aorta smaller than 2 mm in diameter was identified in 21.4% (3/14) of the patients. Ventricular septal defect (n=3), endocardial fibroelastosis (n=2) and coronary ventricular communication (n=1) were detected on cardiac CT. Cardiac CT can be used to assess serial changes in anatomy and ventricular function after the Norwood procedure in patients with hypoplastic left heart syndrome.

[Studies for analyzing prohibited ingredients such as tetracaine hydrochloride in cosmetics].

PubMed

Tokunaga, Hiroshi; Takeuchi, Orie; Uchino, Tadashi; Ando, Masanori

2004-01-01

Tetracaine hydrochloride (TH) is nominated as the prohibited ingredients in cosmetics in Japanese Pharmaceutical Affairs Act. So the analytical method for TH was investigated by HPLC. After adding 5 ml of TH solution at 10 microg/ml and 2 ml of salicylic acid solution at 75 microg/ml as the internal standard to 0.5 g of the lotion, the mixture was made up to 10 ml with a mixture of water and methanol (1:1) as the testing solution. Milky lotion was procedured as follows: After adding 5 ml of TH solution at 10 microg/ml and 2 ml of internal standard solution to 0.5 g of the milky lotion, the mixture was made up to 10 ml with a mixture of water and methanol (1:1). Two milliliter of this mixture was placed into a centrifuging tube with a cap and 2 ml of hexane was added. After shaking vigorously and centrifuging, the lower layer was used as the testing solution. In the case of the cream, the other procedures were used: 0.5 g of cream was placed into a 10-ml volumetric flask and 1 ml of tetrahydrofuran was added. After dissolving, the mixture of methanol and water (1:1) was added to make up 10.0 ml. Two milliliter of this mixture was placed into a centrifuging tube with a cap and 2.0 ml of hexane was added. After shaking vigorously and centrifuging, the lower layer was used as the testing solution. The testing solution of 20 microl was analyzed by HPLC using the ODS column (CAPCELL PAK C18 column, 4.6 x 250 mm), the mixture of acetonitrile and 50 mmol/l phosphate buffer(pH 2.0)(7:3) and the detection wavelength of 303 nm. The working curves from 0.5 to 6.0 microg/ml showed a linear line between the concentrations of TH and the peak area ratio. There was no interference of peak of TH from the lotion, milky lotion and cream.

Volume estimation of small phantoms and rat kidneys using three-dimensional ultrasonography and a position sensor.

PubMed

Strømmen, Kenneth; Stormark, Tor André; Iversen, Bjarne M; Matre, Knut

2004-09-01

To evaluate the accuracy of small volume estimation, both in vivo and in vitro, measurements with a three-dimensional (3D) ultrasound (US) system were carried out. A position sensor was used and the transmitting frequency was 10 MHz. Balloons with known volumes were scanned while rat kidneys were scanned in vivo and in vitro. The Archimedes' principle was used to estimate the true volume. For balloons, the 3D US system gave very good agreement with true volumes in the volume range 0.1 to 10.0 mL (r = 0.999, n = 45, mean difference +/- 2SD = 0.245 +/- 0.370 mL). For rat kidneys in vivo (volume range 0.6 to 2.7 mL) the method was less accurate (r = 0.800, n = 10, mean difference +/- 2SD = -0.288 +/- 0.676 mL). For rat kidneys in vitro (volume range 0.3 to 2.7 mL) the results showed good agreement (r = 0.981, n = 23, mean difference +/- 2SD = 0.039 +/- 0.254 mL). For balloons, kidneys in vivo and in vitro, the mean percentage error was 9.3 +/- 4.8%, -17.1 +/- 17.4%, and 4.6 +/- 11.5%, respectively. This method can estimate the volume of small phantoms and rat kidneys and opens new possibilities for volume measurements of small objects and the study of organ function in small animals. (E-mail ).

Maximum Likelihood Time-of-Arrival Estimation of Optical Pulses via Photon-Counting Photodetectors

NASA Technical Reports Server (NTRS)

Erkmen, Baris I.; Moision, Bruce E.

2010-01-01

Many optical imaging, ranging, and communications systems rely on the estimation of the arrival time of an optical pulse. Recently, such systems have been increasingly employing photon-counting photodetector technology, which changes the statistics of the observed photocurrent. This requires time-of-arrival estimators to be developed and their performances characterized. The statistics of the output of an ideal photodetector, which are well modeled as a Poisson point process, were considered. An analytical model was developed for the mean-square error of the maximum likelihood (ML) estimator, demonstrating two phenomena that cause deviations from the minimum achievable error at low signal power. An approximation was derived to the threshold at which the ML estimator essentially fails to provide better than a random guess of the pulse arrival time. Comparing the analytic model performance predictions to those obtained via simulations, it was verified that the model accurately predicts the ML performance over all regimes considered. There is little prior art that attempts to understand the fundamental limitations to time-of-arrival estimation from Poisson statistics. This work establishes both a simple mathematical description of the error behavior, and the associated physical processes that yield this behavior. Previous work on mean-square error characterization for ML estimators has predominantly focused on additive Gaussian noise. This work demonstrates that the discrete nature of the Poisson noise process leads to a distinctly different error behavior.

Different indicators for postprocedural mitral stenosis caused by single- or multiple-clip implantation after percutaneous mitral valve repair.

PubMed

Itabashi, Yuji; Utsunomiya, Hiroto; Kubo, Shunsuke; Mizutani, Yukiko; Mihara, Hirotsugu; Murata, Mitsushige; Siegel, Robert J; Kar, Saibal; Fukuda, Keiichi; Shiota, Takahiro

2018-04-01

Postprocedural mitral stenosis (MS) is a main limitation for MitraClip™ (Abbot Vascular, Inc., Santa Clara, CA, USA) procedure. The purpose of this study was to detect the preprocedural predictors of high transmitral pressure gradient (TMPG) after MitraClip™ implantation, which indicated postprocedural mitral stenosis (MS). We studied 79 patients who were implanted with MitraClip™ in our institute. Before the procedure, mitral valve orifice area (MVOA), and anterior-posterior (AP) and medial-lateral (ML) mitral annular diameters were measured at diastole using three-dimensional (3D) transesophageal echocardiography (TEE) data set. After the procedure, the mean TMPG was assessed using continuous-wave (CW) Doppler by periprocedural TEE. Preprocedural MVOA, and AP and ML diameter of left ventricular (LV) inflow orifices were larger in patients with mean TMPG ≤4mmHg than in patients with TMPG >4mmHg after 1-and 2-clip implantation. The large MVOA and ML diameter of LV inflow orifice strongly correlated with the low TMPG after 1- and 2-clip implantation. As a result of the receiver operating characteristic curve analysis, the preprocedural MVOA predicted the low postprocedural TMPG more accurately than the ML diameter of LV inflow orifice after 1-clip implantation either in the degenerative or functional mitral regurgitation (MR) patients. After 2-clip implantation, however, the preprocedural ML diameter of LV inflow orifice predicted it more accurately than the MVOA in the degenerative and functional MR patients. 3D TEE derived MVOA predicts the postprocedural MS after 1-clip implantation, however, preprocedural ML diameter of LV inflow orifice is more useful to predict after 2-clip implantation. Copyright © 2017 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.

Simultaneous measurement of chlorophyll and astaxanthin in Haematococcus pluvialis cells by first-order derivative ultraviolet-visible spectrophotometry.

PubMed

Lababpour, Abdolmajid; Lee, Choul-Gyun

2006-02-01

A first-order derivative spectrophotometric method has been developed for the simultaneous measurement of chlorophyll and astaxanthin concentrations in Haematococcus pluvialis cells. Acetone was selected for the extraction of pigments because of its good sensitivity and low toxicity compared with other organic solvents tested; the tested solvents included acetone, methanol, hexane, chloroform, n-propanol, and acetonitrile. A first-order derivative spectrophotometric method was used to eliminate the effects of the overlaping of the chlorophyll and astaxanthin peaks. The linear ranges in 1D evaluation were from 0.50 to 20.0 microg x ml(-1) for chlorophyll and from 1.00 to 12.0 microg x ml(-1) for astaxanthin. The limits of detection of the analytical procedure were found to be 0.35 microg x ml(-1) for chlorophyll and 0.25 microg x ml(-1) for astaxanthin. The relative standard deviations for the determination of 7.0 microg x ml(-1) chlorophyll and 5.0 microg x ml(-1) astaxanthin were 1.2% and 1.1%, respectively. The procedure was found to be simple, rapid, and reliable. This method was successfully applied to the determination of chlorophyll and astaxanthin concentrations in H. pluvialis cells. A good agreement was achieved between the results obtained by the proposed method and HPLC method.

Use of topical tranexamic acid or aminocaproic acid to prevent bleeding after major surgical procedures.

PubMed

Ipema, Heather J; Tanzi, Maria G

2012-01-01

To evaluate the literature describing topical use of tranexamic acid or aminocaproic acid for prevention of postoperative bleeding after major surgical procedures. Literature was retrieved through MEDLINE (1946-September 2011) and International Pharmaceutical Abstracts (1970-September 2011) using the terms tranexamic acid, aminocaproic acid, antifibrinolytic, topical, and surgical. In addition, reference citations from publications identified were reviewed. All identified articles in English were evaluated. Clinical trials, case reports, and meta-analyses describing topical use of tranexamic acid or aminocaproic acid to prevent postoperative bleeding were included. A total of 16 publications in the setting of major surgical procedures were included; the majority of data were for tranexamic acid. For cardiac surgery, 4 trials used solutions containing tranexamic acid (1-2.5 g in 100-250 mL of 0.9% NaCl), and 1 trial assessed a solution containing aminocaproic acid (24 g in 250 mL of 0.9% NaCl). These solutions were poured into the chest cavity before sternotomy closure. For orthopedic procedures, all of the data were for topical irrigation solutions containing tranexamic acid (500 mg-3 g in 50-100 mL of 0.9% NaCl) or for intraarticular injections of tranexamic acid (250 mg to 2 g in 20-50 mL of 0.9% sodium chloride, with or without carbazochrome sodium sulfate). Overall, use of topical tranexamic acid or aminocaproic acid reduced postoperative blood loss; however, few studies reported a significant reduction in the number of packed red blood cell transfusions or units given, intensive care unit stay, or length of hospitalization. Topical application of tranexamic acid and aminocaproic acid to decrease postsurgical bleeding after major surgical procedures is a promising strategy. Further data are needed regarding the safety of this hemostatic approach.

[Mechanical autologous transfusion in orthopedic surgery in children. Is the use of mechanical autologous transfusion possible even in pediatric orthopedic surgical procedures?].

PubMed

Michaelis, G; Melzer, C; Biscoping, J; Hempelmann, G

1995-07-01

The use of autotransfusion devices is an established method of reducing the need for homologous transfusions in surgery [3, 11, 13], but technical factors still contraindicate the washing and concentration of blood volumes smaller than 300 ml. Therefore, haemoconcentration of small volumes of salvaged blood, as usually found in paediatric surgery, is considered to be a complicated and questionable practice [5]. Whereas these amounts of blood loss are easily tolerated by adults, they may necessitate homologous transfusions in paediatric surgery. In a prospective study, we investigated whether a simple technical modification in the processing of salvaged blood could facilitate the use of autotransfusion devices, especially in children. PATIENTS AND METHODS. Intraoperative blood salvage was performed in children 6 months to 10 years old undergoing surgery for hip dysplasia. Autotransfusion (Dideco STAT) was started when the blood loss was estimated to be more than 20% of the total blood volume (TBV). As a reference, we used a formula based on body weight [10]: for children up to the age of 6 years 80 ml/kg blood volume and for children up to 10 years 75 ml/kg. The total volume of salvaged fluid including blood, anticoagulant solution, and surgical irrigation was collected in a reservoir and transferred to the autotransfusion set, after which the reservoir was rinsed with 500 ml 0.9% saline solution in order to save the remaining blood. After processing, the blood was stored in the retransfusion bag. By adding the same volume of plasma expander (6% hydroxyethyl starch [HES], molecular weight 450,000), spontaneous sedimentation of the washed autologous erythrocytes (RBCs) for 10-15 min led to a concentrate of RBCs. After 10 mu filtration, the RBC suspension was retransfused (Figs. 1-3). RESULTS. Within 12 months, autotransfusion was performed during 6 out of 15 surgical procedures according to the method described above. The calculated blood loss averaged 25.6% of TBV, of which 21.4% (= 272 ml) could be processed by the autotransfusion device (Table 3). The mean values of 2.6 g/dl haemoglobin (Hb) and 6.8% haematocrit (HCt) in the salvaged blood increased to 9.4 g/dl and 27.3% in the processed RBC concentrates. After adding 6% HES solution, spontaneous sedimentation of the RBCs led to values of Hb 22.1 g/dl and HCt 59.8%. An average of 59.5 ml (22-99 ml) sedimented RBCs was retransfused to the patients, including 11.6 ml 6% HES solution (Table 4). In this manner, the need for homologous transfusions could be avoided in these patients both during and after surgery. CONCLUSIONS. This study shows that the use of blood salvaging in paediatric surgery is indicated under certain conditions. With the aid of the simple modification described above, we solved the main problem in paediatric autotransfusion by concentrating RBC suspensions with low Hb and Hct values after using the autotransfusion device.

Analyzing average and conditional effects with multigroup multilevel structural equation models

PubMed Central

Mayer, Axel; Nagengast, Benjamin; Fletcher, John; Steyer, Rolf

2014-01-01

Conventionally, multilevel analysis of covariance (ML-ANCOVA) has been the recommended approach for analyzing treatment effects in quasi-experimental multilevel designs with treatment application at the cluster-level. In this paper, we introduce the generalized ML-ANCOVA with linear effect functions that identifies average and conditional treatment effects in the presence of treatment-covariate interactions. We show how the generalized ML-ANCOVA model can be estimated with multigroup multilevel structural equation models that offer considerable advantages compared to traditional ML-ANCOVA. The proposed model takes into account measurement error in the covariates, sampling error in contextual covariates, treatment-covariate interactions, and stochastic predictors. We illustrate the implementation of ML-ANCOVA with an example from educational effectiveness research where we estimate average and conditional effects of early transition to secondary schooling on reading comprehension. PMID:24795668

Stereolithographic skull models in the surgical planning of fronto-supraorbital bar advancement for non-syndromic trigonocephaly.

PubMed

van Nunen, D P F; Janssen, L E; Stubenitsky, B M; Han, K S; Muradin, M S M

2014-09-01

Fronto-supraorbital bar advancement in the treatment for trigonocephaly is associated with extensive intraoperative blood loss and compensatory erythrocyte transfusions. Since both are related to the length of surgery, efforts have been focused on optimizing preoperative preparations. The utilization of three-dimensional skull models in surgical planning allows for familiarization with the patient's anatomy, the optimization of osteotomies, the preparation of bone grafts and the selection of fixation plates. Stereolithographic skull models were used in the surgical planning for five patients with non-syndromic trigonocephaly treated in Wilhelmina Children's Hospital in 2012. A comparison group was composed of six patients with non-syndromic trigonocephaly treated by the same surgical team. Once all patients had received surgery, a retrospective chart review was performed to identify the volumes of perioperative blood loss and erythrocyte transfusions and the length of the procedure. Furthermore, the educational value of the models was assessed in a round table discussion with the surgical team and residents. In the model group patients were transfused a mean 24 ml/kg (27% of Estimated Blood Volume [EBV]) compared to 16 ml/kg (18% of EBV) in the comparison group (P = 0.359) for a mean perioperative blood loss of 53 ml/kg (60% of EBV) in the model group against 40 ml/kg (41% of EBV) in the comparison group (P = 0.792). The mean length of surgery in the model groups was 256 min versus 252 min in the comparison group (P = 0.995). Evaluation of educational purposes demonstrated that the models had a role in the instruction of residents and communication to parents, but did not improve the insight of experienced surgeons. The usage of stereolithographic skull models in the treatment of non-syndromic trigonocephaly does not reduce the mean volume of perioperative erythrocyte transfusions, the mean volume of perioperative blood loss nor the mean length of the surgical procedure. Nonetheless, the models do facilitate the education of the patient's parents as well as support the training of residents. Copyright © 2014 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

Adaptive early detection ML/PDA estimator for LO targets with EO sensors

NASA Astrophysics Data System (ADS)

Chummun, Muhammad R.; Kirubarajan, Thiagalingam; Bar-Shalom, Yaakov

2000-07-01

The batch Maximum Likelihood Estimator, combined with Probabilistic Data (ML-PDA), has been shown to be effective in acquiring low observable (LO) - low SNR - non-maneuvering targets in the presence of heavy clutter. The use of signal strength or amplitude information (AI) in the ML-PDA estimator with AI in a sliding-window fashion, to detect high- speed targets in heavy clutter using electro-optical (EO) sensors. The initial time and the length of the sliding-window are adjusted adaptively according to the information content of the received measurements. A track validation scheme via hypothesis testing is developed to confirm the estimated track, that is, the presence of a target, in each window. The sliding-window ML-PDA approach, together with track validation, enables early detection by rejecting noninformative scans, target reacquisition in case of temporary target disappearance and the handling of targets with speeds evolving over time. The proposed algorithm is shown to detect the target, which is hidden in as many as 600 false alarms per scan, 10 frames earlier than the Multiple Hypothesis Tracking (MHT) algorithm.

Primary Fat Grafting to the Pectoralis Muscle during Latissimus Dorsi Breast Reconstruction.

PubMed

Niddam, Jeremy; Vidal, Luciano; Hersant, Barbara; Meningaud, Jean Paul

2016-11-01

Latissimus dorsi flap is one of the best options for immediate and delayed breast reconstruction. However, this technique is limited by the tissue volume provided by the flap. To improve breast volume while reducing complications, fat grafting is now very often used in addition to latissimus dorsi flap. To the best of our knowledge, fat grafting was always performed as a second-line surgery, at least a few months after the flap procedure. We aimed to report our experience with an associated breast reconstruction technique combining musculocutaneous latissimus dorsi flap with intrapectoral lipofilling for totally autologous breast reconstruction. Between September 2014 and January 2015, 20 patients underwent this technique for unilateral autologous breast reconstruction (14 delayed and 6 immediate breast reconstructions). A mean harvested fat volume of 278 ml (range: 190-350 ml) and a mean injected fat volume of 228 ml (range: 170-280 ml) were used. None of the patients experienced complications, such as flap necrosis, breast skin necrosis, hematomas, or infection. One of the patients developed a seroma, which was treated with 3 drainage punctions. Only 2 patients underwent delayed fat grafting procedure. Totally autologous breast reconstruction combining latissimus dorsi flap and intrapectoral fat grafting in the same procedure is a new technique allowing increased breast volume in a single surgery.

A review of 111 anaesthetic patients undergoing cytoreductive surgery and hyperthermic intraperitoneal chemotherapy

PubMed Central

Thong, Sze Ying; Chia, Claramae Shulyn; Ng, Oriana; Tan, Grace; Ong, Ee Teng; Soo, Khee Chee; Teo, Melissa

2017-01-01

INTRODUCTION Cytoreductive surgery (CRS) along with hyperthermic intraperitoneal chemotherapy (HIPEC) is the treatment of choice for selected patients with peritoneal carcinomatosis, a previously lethal condition with dismal survival rates. METHODS We reviewed CRS and HIPEC procedures performed at our centre from January 1997 to December 2012, focusing on perioperative events and anaesthetic implications. RESULTS In total, 111 patients underwent 113 procedures. Mean age of the patients was 51.7 (range 14–74) years and 84.1% were women. Mean duration of surgery was 9 hours 10 minutes ± 2 hours 56 minutes. Most tumours were ovarian or colorectal in origin, and the mean peritoneal cancer index (PCI) score was 14.3 ± 8.9. Mean estimated blood loss was 1,481 ± 1,064 mL. Mean total intravenous fluids and blood products administered was 8,498 ± 3,941 mL. Postoperatively, 79.5% of the patients needed intensive care, as 75.2% of the 113 procedures required interval extubation. Patients with lower PCI scores were more likely to be extubated immediately after surgery (p < 0.05). 80.0% of patients had coagulopathy postoperatively, and this was associated with longer HIPEC duration (p < 0.05). Median lengths of intensive care unit and hospital stays were two days and 14 days, respectively. Longer duration of surgery significantly correlated with longer hospitalisation. Prolonged hospitalisation was due to nosocomial pneumonia, pleural effusions, respiratory failure, sepsis, surgical complications (such as anastomotic or wound dehiscence), and intra-abdominal infections. CONCLUSION The CRS and HIPEC technique is a major surgery with significant morbidity, as highlighted by the perioperative concerns observed in our study. PMID:27121920

Minimum effective volume of mepivacaine for ultrasound-guided supraclavicular block

PubMed Central

Song, Jae Gyok; Kang, Bong Jin; Park, Kee Keun

2013-01-01

Background The aim of this study was to estimate the minimum effective volume (MEV) of 1.5% mepivacaine for ultrasound-guided supraclavicular block by placing the needle near the lower trunk of brachial plexus and multiple injections. Methods Thirty patients undergoing forearm and hand surgery received ultrasound-guided supraclavicular block with 1.5% mepivacaine. The initial volume of local anesthetic injected was 24 ml, and local anesthetic volume for the next patient was determined by the response of the previous patient. The next patient received a 3 ml higher volume in the case of the failure of the previous case. If the previous block was successful, the next volume was 3 ml lower. MEV was estimated by the Dixon and Massey up and down method. MEV in 95, 90, and 50% of patients (MEV95, MEV90, and MEV50) were calculated using probit transformation and logistic regression. Results MEV95 of 1.5% mepivacaine was 17 ml (95% confidence interval [CI], 13-42 ml), MEV90 was 15 ml (95% CI, 12-34 ml), and MEV50 was 9 ml (95% CI, 4-12 ml). Twelve patients had a failed block. Three patients received general anesthesia. Nine patients could undergo surgery with sedation only. Only one patient showed hemi-diaphragmatic paresis. Conclusions MEV95 was 17 ml, MEV90 was 15 ml, and MEV50 was 9 ml. However, needle location near the lower trunk of brachial plexus and multiple injections should be performed. PMID:23904937

Metabolic abnormalities associated with elevated serum cystatin C in adults with an estimated GFR ≥ 60 ml/min/1.73m2

PubMed Central

Muntner, Paul; Vupputuri, Suma; Coresh, Josef; Uribarri, Jaime; Fox, Caroline S.

2011-01-01

Elevated serum cystatin C may represent an early stage of kidney disease. It is unclear whether metabolic abnormalities typically seen in advanced chronic kidney disease are present in adults with estimated glomerular filtration rate ≥60 ml/min/1.73m2 and elevated cystatin C. Participants of the Third National Health and Nutrition Examination Survey (n=6722) were categorized into three groups: estimated glomerular filtration rate ≥ 60 ml/min/1.73m2 and cystatin C <1.09 mg/L (normal cystatin C); estimated glomerular filtration rate ≥60 ml/min/1.73m2 and cystatin C ≥1.09 mg/L (elevated cystatin C); and estimated glomerular filtration rate of 15-59 ml/min/1.73m2 (stage 3 or 4 chronic kidney disease). Among those with normal cystatin C, elevated cystatin C, and stage 3 or 4 chronic kidney disease, the age, race-ethnicity, sex standardized prevalence of serum hemoglobin <12 g/dL (<13 g/dL for men) was 4.3%, 8.2%, and 13.8%; serum uric acid ≥ 5.9 mg/dL (≥7.4 mg/dL for men) was 12.6%, 30.0%, and 45.0%; serum homocysteine ≥13 μmol/L was 12.1%, 25.1%, and 41.0%; serum phosphorus ≥3.9 mg/dL was 17.2%, 23.2%, and 25.8%; serum albumin <3.8 mg/dL was 14.5%, 20.0%, and 20.4%; plasma fibrinogen ≥352 mg/dL was 10.5%, 21.7%, and 23.2%; and C-reactive protein ≥1.0 g/dL was 7.5%, 22.5%, and 21.6% (each p-trend<0.001). Among adults with estimated glomerular filtration rate ≥60 ml/min/1.73m2, elevated serum cystatin C is associated with an increased prevalence of several metabolic abnormalities. PMID:19295502

Fetal blood drawing.

PubMed

Hobbins, J C; Mahoney, M J

1975-07-19

A small sample of fetal blood suitable for studies of haemoglobin synthesis was obtained from a placental vessel under endoscopic visualisation in 23 of 26 patients in whom the procedure was attempted prior to second-trimester abortion. Fetal blood loss, calculated in 23 cases, was between 0-2 ml. and 2-5 ml., and fetal blood-volume depletion varied from 0-5% to 15%. No short-term ill-effects were demonstrated in mother or fetus in any of 16 patients in whom the injection of aborti-facient was postponed for between 16 and 24 hours after the procedure.

Prevention of post procedural acute kidney injury in the catheterization laboratory in a real-world population.

PubMed

Chorin, Ehud; Ben-Assa, Eyal; Konigstein, Maayan; Rofe, May-Tal; Hochstadt, Aviram; Galli, Naama; Schnapper, Michael; Arbel, Yaron; Rabey, Ilan; Shoshan, Jeremy Ben; Halkin, Amir; Herz, Itzhak; Finkelstein, Ariel; Bazan, Samuel; Keren, Gad; Banai, Shmuel

2017-01-01

Radiologists and cardiologists have a remarkably different approach to the clinical importance and to the need for prophylactic treatment of contrast-induced acute kidney injury (CI-AKI). To evaluate the efficacy of forced diuresis with matched controlled hydration (FMH) in a real-world, high risk population. This is an investigator-driven, single-center, retrospective analysis of prospectively collected data. A total of 150 consecutive patients undergoing coronary angiography, angioplasty or TAVR who were treated with FMH were compared to a matched historical control cohort. In the FMH treated patients, eGFR improved following the procedure from 37ml/min per 1.73m 2 at baseline to 39ml/min per 1.73m 2 (p<0.001); the net creatinine decreased from 1.85mg/dl to 1.78mg/dl (p<0.001). Among the matched control group, eGFR deteriorated from a baseline value of 36.7ml/min per 1.73m 2 to 33.2ml/min per 1.73m 2 post procedurally (p<0.001); the net creatinine increased from 1.88mg/dl to 2.14mg/dl (p<0.001). The incidence of post procedural AKI was substantially lower in the FMH treated group (2.7%) compared to the control group (26.7%). By multivariable analysis FMH treatment was independently correlated with reduced incidence of post procedural AKI compared with the control group (OR 0.06, p<0.001). Contrast volume did not correlate with AKI in neither univariate nor multivariate analyses. In patients undergoing coronary angiography, angioplasty or TAVR, who are considered high risk to develop post procedural AKI, forced diuresis with matched controlled hydration resulted in a significant net creatinine decrease, eGFR increase and a decrease in the incidence of AKI. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

21 CFR Appendix A to Part 74 - The Procedure for Determining Ether Soluble Material in D&C Red Nos. 6 and 7

Code of Federal Regulations, 2010 CFR

2010-04-01

... throughout method.) Allow the funnel to stand until the layers have separated. Transfer the bottom (aqueous) layer to a 500 mL separatory funnel, add 100 mL of ether, stopper and shake for one minute. When the layers have separated, drain off the bottom layer into a waste beaker. Pour the ether layer in the 500 mL...

Maximum Likelihood Shift Estimation Using High Resolution Polarimetric SAR Clutter Model

NASA Astrophysics Data System (ADS)

Harant, Olivier; Bombrun, Lionel; Vasile, Gabriel; Ferro-Famil, Laurent; Gay, Michel

2011-03-01

This paper deals with a Maximum Likelihood (ML) shift estimation method in the context of High Resolution (HR) Polarimetric SAR (PolSAR) clutter. Texture modeling is exposed and the generalized ML texture tracking method is extended to the merging of various sensors. Some results on displacement estimation on the Argentiere glacier in the Mont Blanc massif using dual-pol TerraSAR-X (TSX) and quad-pol RADARSAT-2 (RS2) sensors are finally discussed.

Inverse problems-based maximum likelihood estimation of ground reflectivity for selected regions of interest from stripmap SAR data [Regularized maximum likelihood estimation of ground reflectivity from stripmap SAR data

DOE Office of Scientific and Technical Information (OSTI.GOV)

West, R. Derek; Gunther, Jacob H.; Moon, Todd K.

In this study, we derive a comprehensive forward model for the data collected by stripmap synthetic aperture radar (SAR) that is linear in the ground reflectivity parameters. It is also shown that if the noise model is additive, then the forward model fits into the linear statistical model framework, and the ground reflectivity parameters can be estimated by statistical methods. We derive the maximum likelihood (ML) estimates for the ground reflectivity parameters in the case of additive white Gaussian noise. Furthermore, we show that obtaining the ML estimates of the ground reflectivity requires two steps. The first step amounts tomore » a cross-correlation of the data with a model of the data acquisition parameters, and it is shown that this step has essentially the same processing as the so-called convolution back-projection algorithm. The second step is a complete system inversion that is capable of mitigating the sidelobes of the spatially variant impulse responses remaining after the correlation processing. We also state the Cramer-Rao lower bound (CRLB) for the ML ground reflectivity estimates.We show that the CRLB is linked to the SAR system parameters, the flight path of the SAR sensor, and the image reconstruction grid.We demonstrate the ML image formation and the CRLB bound for synthetically generated data.« less

Inverse problems-based maximum likelihood estimation of ground reflectivity for selected regions of interest from stripmap SAR data [Regularized maximum likelihood estimation of ground reflectivity from stripmap SAR data

DOE PAGES

West, R. Derek; Gunther, Jacob H.; Moon, Todd K.

2016-12-01

In this study, we derive a comprehensive forward model for the data collected by stripmap synthetic aperture radar (SAR) that is linear in the ground reflectivity parameters. It is also shown that if the noise model is additive, then the forward model fits into the linear statistical model framework, and the ground reflectivity parameters can be estimated by statistical methods. We derive the maximum likelihood (ML) estimates for the ground reflectivity parameters in the case of additive white Gaussian noise. Furthermore, we show that obtaining the ML estimates of the ground reflectivity requires two steps. The first step amounts tomore » a cross-correlation of the data with a model of the data acquisition parameters, and it is shown that this step has essentially the same processing as the so-called convolution back-projection algorithm. The second step is a complete system inversion that is capable of mitigating the sidelobes of the spatially variant impulse responses remaining after the correlation processing. We also state the Cramer-Rao lower bound (CRLB) for the ML ground reflectivity estimates.We show that the CRLB is linked to the SAR system parameters, the flight path of the SAR sensor, and the image reconstruction grid.We demonstrate the ML image formation and the CRLB bound for synthetically generated data.« less

Death and Dialysis After Transcatheter Aortic Valve Replacement: An Analysis of the STS/ACC TVT Registry.

PubMed

Hansen, James W; Foy, Andrew; Yadav, Pradeep; Gilchrist, Ian C; Kozak, Mark; Stebbins, Amanda; Matsouaka, Roland; Vemulapalli, Sreekanth; Wang, Alice; Wang, Dee Dee; Eng, Marvin H; Greenbaum, Adam B; O'Neill, William O

2017-10-23

The authors sought to elucidate the true incidence of renal replacement therapy (RRT) after transcatheter aortic valve replacement (TAVR). There is a wide discrepancy in the reported rate of RRT after TAVR (1.4% to 40%). The true incidence of RRT after TAVR is unknown. The STS/ACC TVT (Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy) registry was linked to the Centers for Medicare & Medicaid database to identify all patients that underwent TAVR from November 2011 through September 2015 and their outcomes. The authors compared rates of death, new RRT, and a composite of both as a function of pre-procedure glomerular filtration rate (GFR), both in stages of chronic kidney disease (CKD), as well as on a continuous scale. Pre-procedure GFR is associated with the risk of death and new RRT after TAVR when GFR is <60 ml/min/m 2 , and increases significantly when GFR falls below 30 ml/min/m 2 . Incremental increases in GFR of 5 ml/min/m 2 were statistically significant (unadjusted hazard ratio: 0.71; p < 0.001) at 30 days, and continued to be significant at 1 year when pre-procedure GFR was <60 ml/min/m 2 . One in 3 CKD stage 4 patients will be dead within 1 year, with 14.6% (roughly 1 in 6) requiring dialysis. In CKD stage 5, more than one-third of patients will require RRT within 30 days; nearly two-thirds will require RRT at 1 year. In both unadjusted and adjusted analysis, pre-procedural GFR was associated with the outcomes of death and new RRT. Increasing CKD stage leads to an increased risk of death and/or RRT. Continuous analysis showed significant differences in outcomes in all levels of CKD when GFR was <60 ml/min/m 2 . Pre-procedure GFR should be considered when selecting CKD patients for TAVR. Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Glomerular filtration rate estimation from plasma creatinine after inhibition of tubular secretion: relevance of the creatinine assay.

PubMed

Kemperman, F A; Silberbusch, J; Slaats, E H; van Zanten, A P; Weber, J A; Krediet, R T; Arisz, L

1999-05-01

Estimation of glomerular filtration rate (GFR) from plasma creatinine concentration after inhibition of tubular creatinine secretion with cimetidine provides a good assessment in patients with various nephropathies and with non-insulin-dependent diabetes mellitus (NIDDM). The aim of this study was to compare cimetidine-aided GFR estimations using various creatinine assays. In 30 outpatients with NIDDM GFR was measured as the urinary clearance of continuously infused [125I]iothalamate. Plasma creatinine concentration was analysed after oral cimetidine with an alkaline picrate (AP) method, with an enzymatic (PAP) assay and with HPLC. GFR estimations were calculated with the Cockcroft Gault formula (CG). AP creatinine concentrations were significantly higher than PAP or HPLC values. GFR estimations by AP (CG(AP) 66 +/- 19 ml/min/1.73 m2, mean SD) were significantly lower than GFR (89 +/- 30), whereas CG(PAP) (85 +/- 30) and CG(HPLC) (84 +/- 34 ml/min/1.73 m2) were not. Bland and Altman analysis showed a difference between CG(AP) and GFR of -22.4 +/- 17.7 ml/min/1.73 m2; this difference becomes larger when the GFR increases. The difference between CG and GFR was only -3.8 +/- 14.8 ml/min/1.73 m2 for PAP and -4.4 +/- 17.5 ml/min/1.73 m2 for HPLC, without any systematic difference. A good assessment of the GFR from plasma creatinine after cimetidine administration is possible when creatinine is measured with an enzymatic assay or with the less convenient HPLC method. The more widespread and cheaper alkaline picrate assay is not suitable for GFR-estimation.

DiscML: an R package for estimating evolutionary rates of discrete characters using maximum likelihood.

PubMed

Kim, Tane; Hao, Weilong

2014-09-27

The study of discrete characters is crucial for the understanding of evolutionary processes. Even though great advances have been made in the analysis of nucleotide sequences, computer programs for non-DNA discrete characters are often dedicated to specific analyses and lack flexibility. Discrete characters often have different transition rate matrices, variable rates among sites and sometimes contain unobservable states. To obtain the ability to accurately estimate a variety of discrete characters, programs with sophisticated methodologies and flexible settings are desired. DiscML performs maximum likelihood estimation for evolutionary rates of discrete characters on a provided phylogeny with the options that correct for unobservable data, rate variations, and unknown prior root probabilities from the empirical data. It gives users options to customize the instantaneous transition rate matrices, or to choose pre-determined matrices from models such as birth-and-death (BD), birth-death-and-innovation (BDI), equal rates (ER), symmetric (SYM), general time-reversible (GTR) and all rates different (ARD). Moreover, we show application examples of DiscML on gene family data and on intron presence/absence data. DiscML was developed as a unified R program for estimating evolutionary rates of discrete characters with no restriction on the number of character states, and with flexibility to use different transition models. DiscML is ideal for the analyses of binary (1s/0s) patterns, multi-gene families, and multistate discrete morphological characteristics.

[Consequences of new patient discharge guidelines on the cost structure of radioiodine therapy].

PubMed

Dietlein, M; Troche, C J; Moka, D; Bausch, V; Lauterbach, K W; Schicha, H

1998-01-01

Consequences of the new recommendations by the Federal German Radiation Protection Committee (SSK) for patient discharge guidelines (residual activity of 250 MBq for I-131) were calculated for duration of stay and radioiodine therapy cost management. For 601 consecutively admitted patients with hyperthyreosis, actual duration of stay and duration of stay according to previous guidelines (from 1993) were calculated, as well as duration of stay according to recommended values. Following BPflV statutes, cost-analysis considered the cause and volume of goitre, and by using sensitivity analyses included a range of diagnostics, service assessment, and duration of stay. Duration of stay following I-131 therapy (in Germany) is expected to fall by 35-50% (average future stay 4.0 +/- 2.8 days), average costs from DM 4,452 to DM 3,680 (-17.4%). Not including pretreatment diagnostics, cost reduction (service assessment 17-24%) was estimated at 21-25%. Compared to strumectomy, I-131 therapy costs are expected to be lower for goitres (Graves' disease) up to at least 60 ml, toxic nodules of at least 25 ml, and toxic multinodular goitres of at least 90 ml. In the future, I-131 therapy will be more cost-effective even with larger goitres. Since reimbursement is determined by the duration of stay, new reimbursement procedures are discussed in this paper.

Spectrophotometric determination of pipazethate HCl, dextromethorphan HBr and drotaverine HCl in their pharmaceutical preparations

NASA Astrophysics Data System (ADS)

Amin, Alaa S.; El-Sheikh, Ragaa; Zahran, Faten; Gouda, Ayman Abou El-fetouh

2007-07-01

A simple, accurate and highly sensitive spectrophotometric method is proposed for the rapid determination of pipazethate hydrochloride, dextromethorphan hydrobromide and drotaverine hydrochloride using chromotrope 2B (C2B) and chromotrope 2R (C2R). The method consists of extracting the formed ion-associates into chloroform in the case of pipazethate HCl and dextromethorphan HBr or into methylene chloride in the case of drotaverine HCl. The ion-associates exhibit absorption maxima at 528, 540 and 532 nm with C2B and at 526, 517 and 522 nm with C2R for pipazethate HCl, dextromethorphan HBr and drotaverine HCl, respectively. The calibration curves resulting from the measurements of absorbance-concentration relations (at the optimum reaction conditions) of the extracted ion-pairs are linear over the concentration range 4.36-52.32 μg mL -1 for pipazethate, 3.7-48.15 μg mL -1 for dextromethorphan and 4.34-60.76 μg mL -1 for drotaverine, respectively. The effect of acidity, reagent concentration, time, solvent and stoichiometric ratio of the ion-associates were estimated. The molar absorptivity and Sandell sensitivity of the reaction products were calculated. Statistical treatment of the results reflects that the procedure is precise, accurate and easily applied for the determination of the drugs under investigation in pure form and in their pharmaceutical preparations.

Beat by beat stroke volume assessment by PDE in upright and supine exercise

NASA Technical Reports Server (NTRS)

1980-01-01

A 3.0 MHz pulse Doppler echocardiograph was used to estimate instantaneous stroke volume and cardiac output in 8 men during steady state supine and upright exercise at 300 kpm/min which were compared with other studies utilizing invasive procedures. The mean transients in heart rate and stroke volume and cardiac output for the first 20 sec of exercise in each posture were then determined. Centerline blood velocities were obtained in the ascending aorta with the transducer positioned manually in the suprasternal notch. Mean supine values for stroke volume and cardiac output at rest and exercise were 111 (6.4) and 112 ml (9.7 L/min), respectively, for supine. The corresponding results for upright were 76 (5.6) and 92 ml (8.4 L/min). These values compare favorably with prior studies. The transient response of cardiac output following the onset of upright was about twice as fast as in S because of the rapid and almost immediate upsurge in stroke volume. In supine, only heart rate served to augment cardiac output as stroke volume initially fell. The faster initial aortic flow in upright must represent the rapid mobilization of pooled venous blood from the leg veins which more than accounts for the additional volume (184 ml) of blood passing through the aorta during upright compared with supine in the first 20 sec.

High radioactive concentration of 99mTc from a zirconium [99Mo]molybdate gel generator using an acidic alumina column for purification and concentration.

PubMed

Sarkar, S K; Saraswathy, P; Arjun, G; Ramamoorthy, N

2004-06-01

Newer applications of radiopharmaceuticals in nuclear medicine require pertechnetate of moderate to high radioactive concentration. Hence there is a need to develop simple procedures for the concentration of pertechnetate, and such a procedure is given in this paper. Ten to 20 ml of sodium [Tc]pertechnetate eluted in de-ionized water from a zirconium [Mo]molybdate (ZrMo) gel column generator was passed through 2 g of an acidic alumina bed (35 x 8 mm) in order to remove the co-eluted traces of Mo and to retain the pertechnetate. The retained pertechnetate was then re-eluted, quantitatively, in 3 ml of normal saline, from the alumina column. About a 4-fold increase in radioactive concentration of Tc was obtained (cf. approximately 10-12 ml normal saline is required for the elution of Tc from the gel column). Generators containing up to 22.2 GBq (600 mCi) Mo in 6-7 g ZrMo gel column (35 x 13 mm) were prepared and a radioactive concentration of Tc up to 4 GBq x ml (110 mCi x ml) was obtained on the first day of use. The overall recovery of Tc was >90%, Mo breakthrough was 10 to 10% and the duration of concentration was 3-5 min. The chemical impurity in terms of Al, Mo and Zr was <10 ppm each. The same procedure for the concentration of pertechnetate was applied to generators with 12-15 g ZrMo gel beds to obtain a higher capacity Tc gel generator, with similar findings.

The minimal ice water caloric test compared with established vestibular caloric test procedures.

PubMed

Schmäl, Frank; Lübben, Björn; Weiberg, Kerstin; Stoll, Wolfgang

2005-01-01

Caloric testing of the vestibular labyrinth is usually performed by classical caloric test procedures (CCTP) using water warmed to 30 degrees C and 44 degrees C. Ice water irrigation (4 degrees C) is usually not performed, although it might be useful as a bedside test. To verify the validity of the Minimal Ice Water Caloric Test (MIWCT), comparative video-oculographic investigations were performed in 22 healthy subjects using ice water (0.5 ml, 1.0 ml, 2 ml), CCTP, and cold air (27 degrees C). Frequency, amplitude, slow phase velocity (SPV), the onset, and the duration of nystagmus were documented. After addition of three ice cubes, the temperature of conventional tap water (16 degrees C) fell within 13 min to 4 degrees C. In pessimum position the subjects demonstrated no nystagmus response. Compared to CCTP, MIWCT was associated with a significantly later onset of nystagmus and a significant prolongation of the nystagmus reaction. In contrast to air stimulation (27 degrees C), a significant Spearman's correlation was noted between MIWCT (1 and 2 ml) and established CCTP in respect of essential nystagmus parameters (frequency, amplitude and SPV). Furthermore, MIWCT (0.5 and 1 ml) showed a higher sensitivity and specificity with regard to the detection of canal paresis based on Jongkees' formula compared to stimulation with air 27 degrees C. Thus, MIWCT appears to be a suitable procedure for bedside investigation of vestibular function outside the vestibular laboratory, e.g. in a hospital ward, where bedridden patients with vertigo occasionally require vestibular testing.

Exsanguinated blood volume estimation using fractal analysis of digital images.

PubMed

Sant, Sonia P; Fairgrieve, Scott I

2012-05-01

The estimation of bloodstain volume using fractal analysis of digital images of passive blood stains is presented. Binary digital photos of bloodstains of known volumes (ranging from 1 to 7 mL), dispersed in a defined area, were subjected to image analysis using FracLac V. 2.0 for ImageJ. The box-counting method was used to generate a fractal dimension for each trial. A positive correlation between the generated fractal number and the volume of blood was found (R(2) = 0.99). Regression equations were produced to estimate the volume of blood in blind trials. An error rate ranging from 78% for 1 mL to 7% for 6 mL demonstrated that as the volume increases so does the accuracy of the volume estimation. This method used in the preliminary study proved that bloodstain patterns may be deconstructed into mathematical parameters, thus removing the subjective element inherent in other methods of volume estimation. © 2012 American Academy of Forensic Sciences.

Causal mediation analysis with a binary outcome and multiple continuous or ordinal mediators: Simulations and application to an alcohol intervention.

PubMed

Nguyen, Trang Quynh; Webb-Vargas, Yenny; Koning, Ina M; Stuart, Elizabeth A

We investigate a method to estimate the combined effect of multiple continuous/ordinal mediators on a binary outcome: 1) fit a structural equation model with probit link for the outcome and identity/probit link for continuous/ordinal mediators, 2) predict potential outcome probabilities, and 3) compute natural direct and indirect effects. Step 2 involves rescaling the latent continuous variable underlying the outcome to address residual mediator variance/covariance. We evaluate the estimation of risk-difference- and risk-ratio-based effects (RDs, RRs) using the ML, WLSMV and Bayes estimators in Mplus. Across most variations in path-coefficient and mediator-residual-correlation signs and strengths, and confounding situations investigated, the method performs well with all estimators, but favors ML/WLSMV for RDs with continuous mediators, and Bayes for RRs with ordinal mediators. Bayes outperforms WLSMV/ML regardless of mediator type when estimating RRs with small potential outcome probabilities and in two other special cases. An adolescent alcohol prevention study is used for illustration.

Branch length estimation and divergence dating: estimates of error in Bayesian and maximum likelihood frameworks.

PubMed

Schwartz, Rachel S; Mueller, Rachel L

2010-01-11

Estimates of divergence dates between species improve our understanding of processes ranging from nucleotide substitution to speciation. Such estimates are frequently based on molecular genetic differences between species; therefore, they rely on accurate estimates of the number of such differences (i.e. substitutions per site, measured as branch length on phylogenies). We used simulations to determine the effects of dataset size, branch length heterogeneity, branch depth, and analytical framework on branch length estimation across a range of branch lengths. We then reanalyzed an empirical dataset for plethodontid salamanders to determine how inaccurate branch length estimation can affect estimates of divergence dates. The accuracy of branch length estimation varied with branch length, dataset size (both number of taxa and sites), branch length heterogeneity, branch depth, dataset complexity, and analytical framework. For simple phylogenies analyzed in a Bayesian framework, branches were increasingly underestimated as branch length increased; in a maximum likelihood framework, longer branch lengths were somewhat overestimated. Longer datasets improved estimates in both frameworks; however, when the number of taxa was increased, estimation accuracy for deeper branches was less than for tip branches. Increasing the complexity of the dataset produced more misestimated branches in a Bayesian framework; however, in an ML framework, more branches were estimated more accurately. Using ML branch length estimates to re-estimate plethodontid salamander divergence dates generally resulted in an increase in the estimated age of older nodes and a decrease in the estimated age of younger nodes. Branch lengths are misestimated in both statistical frameworks for simulations of simple datasets. However, for complex datasets, length estimates are quite accurate in ML (even for short datasets), whereas few branches are estimated accurately in a Bayesian framework. Our reanalysis of empirical data demonstrates the magnitude of effects of Bayesian branch length misestimation on divergence date estimates. Because the length of branches for empirical datasets can be estimated most reliably in an ML framework when branches are <1 substitution/site and datasets are > or =1 kb, we suggest that divergence date estimates using datasets, branch lengths, and/or analytical techniques that fall outside of these parameters should be interpreted with caution.

Estimating Mixing Heights Using Microwave Temperature Profiler

NASA Technical Reports Server (NTRS)

Nielson-Gammon, John; Powell, Christina; Mahoney, Michael; Angevine, Wayne

2008-01-01

A paper describes the Microwave Temperature Profiler (MTP) for making measurements of the planetary boundary layer thermal structure data necessary for air quality forecasting as the Mixing Layer (ML) height determines the volume in which daytime pollution is primarily concentrated. This is the first time that an airborne temperature profiler has been used to measure the mixing layer height. Normally, this is done using a radar wind profiler, which is both noisy and large. The MTP was deployed during the Texas 2000 Air Quality Study (TexAQS-2000). An objective technique was developed and tested for estimating the ML height from the MTP vertical temperature profiles. In order to calibrate the technique and evaluate the usefulness of this approach, estimates from a variety of measurements during the TexAQS-2000 were compared. Estimates of ML height were used from radiosondes, radar wind profilers, an aerosol backscatter lidar, and in-situ aircraft measurements in addition to those from the MTP.

Plane-dependent ML scatter scaling: 3D extension of the 2D simulated single scatter (SSS) estimate.

PubMed

Rezaei, Ahmadreza; Salvo, Koen; Vahle, Thomas; Panin, Vladimir; Casey, Michael; Boada, Fernando; Defrise, Michel; Nuyts, Johan

2017-07-24

Scatter correction is typically done using a simulation of the single scatter, which is then scaled to account for multiple scatters and other possible model mismatches. This scaling factor is determined by fitting the simulated scatter sinogram to the measured sinogram, using only counts measured along LORs that do not intersect the patient body, i.e. 'scatter-tails'. Extending previous work, we propose to scale the scatter with a plane dependent factor, which is determined as an additional unknown in the maximum likelihood (ML) reconstructions, using counts in the entire sinogram rather than only the 'scatter-tails'. The ML-scaled scatter estimates are validated using a Monte-Carlo simulation of a NEMA-like phantom, a phantom scan with typical contrast ratios of a 68 Ga-PSMA scan, and 23 whole-body 18 F-FDG patient scans. On average, we observe a 12.2% change in the total amount of tracer activity of the MLEM reconstructions of our whole-body patient database when the proposed ML scatter scales are used. Furthermore, reconstructions using the ML-scaled scatter estimates are found to eliminate the typical 'halo' artifacts that are often observed in the vicinity of high focal uptake regions.

Parameter Estimation of Multiple Frequency-Hopping Signals with Two Sensors

PubMed Central

Pan, Jin; Ma, Boyuan

2018-01-01

This paper essentially focuses on parameter estimation of multiple wideband emitting sources with time-varying frequencies, such as two-dimensional (2-D) direction of arrival (DOA) and signal sorting, with a low-cost circular synthetic array (CSA) consisting of only two rotating sensors. Our basic idea is to decompose the received data, which is a superimposition of phase measurements from multiple sources into separated groups and separately estimate the DOA associated with each source. Motivated by joint parameter estimation, we propose to adopt the expectation maximization (EM) algorithm in this paper; our method involves two steps, namely, the expectation-step (E-step) and the maximization (M-step). In the E-step, the correspondence of each signal with its emitting source is found. Then, in the M-step, the maximum-likelihood (ML) estimates of the DOA parameters are obtained. These two steps are iteratively and alternatively executed to jointly determine the DOAs and sort multiple signals. Closed-form DOA estimation formulae are developed by ML estimation based on phase data, which also realize an optimal estimation. Directional ambiguity is also addressed by another ML estimation method based on received complex responses. The Cramer-Rao lower bound is derived for understanding the estimation accuracy and performance comparison. The verification of the proposed method is demonstrated with simulations. PMID:29617323

Five methods of breast volume measurement: a comparative study of measurements of specimen volume in 30 mastectomy cases.

PubMed

Kayar, Ragip; Civelek, Serdar; Cobanoglu, Murat; Gungor, Osman; Catal, Hidayet; Emiroglu, Mustafa

2011-03-27

To compare breast volume measurement techniques in terms of accuracy, convenience, and cost. Breast volumes of 30 patients who were scheduled to undergo total mastectomy surgery were measured preoperatively by using five different methods (mammography, anatomic [anthropometric], thermoplastic casting, the Archimedes procedure, and the Grossman-Roudner device). Specimen volume after total mastectomy was measured in each patient with the water displacement method (Archimedes). The results were compared statistically with the values obtained by the five different methods. The mean mastectomy specimen volume was 623.5 (range 150-1490) mL. The breast volume values were established to be 615.7 mL (r = 0.997) with the mammographic method, 645.4 mL (r = 0.975) with the anthropometric method, 565.8 mL (r = 0.934) with the Grossman-Roudner device, 583.2 mL (r = 0.989) with the Archimedes procedure, and 544.7 mL (r = 0.94) with the casting technique. Examination of r values revealed that the most accurate method was mammography for all volume ranges, followed by the Archimedes method. The present study demonstrated that the most accurate method of breast volume measurement is mammography, followed by the Archimedes method. However, when patient comfort, ease of application, and cost were taken into consideration, the Grossman-Roudner device and anatomic measurement were relatively less expensive, and easier methods with an acceptable degree of accuracy.

Determination of L-carnitine, acetyl-L-carnitine and propionyl-L-carnitine in human plasma by high-performance liquid chromatography after pre-column derivatization with 1-aminoanthracene.

PubMed

Longo, A; Bruno, G; Curti, S; Mancinelli, A; Miotto, G

1996-11-15

A new sensitive high-performance liquid chromatographic procedure for the determination of L-carnitine (LC), acetyl-L-carnitine (ALC) and propionyl-L-carnitine (PLC) in human plasma has been developed. Precolumn derivatization with 1-aminoanthracene (1AA), performed in phosphate buffer in the presence of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) as catalyst, is involved. The fluorescent derivatives were isocratically separated on a reversed-phase column (C18). The eluate was monitored with a fluorimetric detector set at 248 nm (excitation wavelength) and 418 nm (emission wavelength). Because of the presence of endogenous carnitines, the validation was performed using dialyzed plasma. The identity of the derivatized compounds was assessed by mass spectrometry and the purity of the chromatographic peaks was confirmed by HPLC-tandem mass spectrometry. The limits of quantitation were 5 nmol/ml for LC, 1 nmol/ml for ALC and 0.25 nmol/ml for PLC. The recovery of the extraction procedure was in the range 82.6%-95.4% for all 3 compounds. Good linearity (R approximately 0.99) was observed within the calibration ranges studied: 5-160 nmol/ml for LC, 1-32 nmol/ml for ALC and 0.25-8 nmol/ml for PLC. Precision was in the range 0.3-16.8% and accuracy was always lower than 10.6%.

Quest for a Realistic In Vivo Test Method for Antimicrobial Hand-Rub Agents: Introduction of a Low-Volume Hand Contamination Procedure▿

PubMed Central

Macinga, David R.; Beausoleil, Christopher M.; Campbell, Esther; Mulberry, Gayle; Brady, Ann; Edmonds, Sarah L.; Arbogast, James W.

2011-01-01

A novel method has been developed for the evaluation of alcohol-based hand rubs (ABHR) that employs a hand contamination procedure that more closely simulates the in-use conditions of ABHR. Hands of human subjects were contaminated with 0.2 ml of a concentrated suspension of Serratia marcescens (ATCC 14756) to achieve baseline contamination between 8 and 9 log10 CFU/hand while allowing product to be applied to dry hands with minimal soil load. Evaluation of 1.5 ml of an ABHR gel containing 62% ethanol produced log10 reductions of 2.66 ± 0.96, 2.40 ± 0.50, 2.41 ± 0.61, and 2.33 ± 0.49 (means ± standard deviations) after 1, 3, 7, and 10 successive contamination/product application cycles. In a study comparing this low-volume contamination (LVC) method to ASTM E1174, product dry times were more realistic and log10 reductions achieved by the ABHR were significantly greater when LVC was employed (P < 0.05). These results indicate that a novel low-volume hand contamination procedure, which more closely represents ABHR use conditions, provides more realistic estimates of in-use ABHR efficacies. Based on the LVC method, log10 reductions produced by ABHR were strongly dependent on the test product application volume (P < 0.0001) but were not influenced by the alcohol concentration when it was within the range of 62 to 85% (P = 0.378). PMID:22003004

Performance Characteristics of the QUANTIPLEX HIV-1 RNA 3.0 Assay for Detection and Quantitation of Human Immunodeficiency Virus Type 1 RNA in Plasma

PubMed Central

Erice, Alejo; Brambilla, Donald; Bremer, James; Jackson, J. Brooks; Kokka, Robert; Yen-Lieberman, Belinda; Coombs, Robert W.

2000-01-01

The QUANTIPLEX HIV-1 RNA assay, version 3.0 (a branched DNA, version 3.0, assay [bDNA 3.0 assay]), was evaluated by analyzing spiked and clinical plasma samples and was compared with the AMPLICOR HIV-1 MONITOR Ultrasensitive (ultrasensitive reverse transcription-PCR [US-RT-PCR]) method. A panel of spiked plasma samples that contained 0 to 750,000 copies of human immunodeficiency virus type 1 (HIV-1) RNA per ml was tested four times in each of four laboratories (1,344 assays). Negative results (<50 copies/ml) were obtained in 30 of 32 (94%) assays with seronegative samples, 66 of 128 (52%) assays with HIV-1 RNA at 50 copies/ml, and 5 of 128 (4%) assays with HIV-1 RNA at 100 copies/ml. The assay was linear from 100 to 500,000 copies/ml. The within-run standard deviation (SD) of the log10 estimated HIV-1 RNA concentration was 0.08 at 1,000 to 500,000 copies/ml, increased below 1,000 copies/ml, and was 0.17 at 100 copies/ml. Between-run reproducibility at 100 to 500 copies/ml was <0.10 log10 in most comparisons. Interlaboratory differences across runs were ≤0.10 log10 at all concentrations examined. A subset of the panel (25 to 500 copies/ml) was also analyzed by the US-RT-PCR assay. The within-run SD varied inversely with the log10 HIV-1 RNA concentration but was higher than the SD for the bDNA 3.0 assay at all concentrations. Log-log regression analysis indicated that the two methods produced very similar estimates at 100 to 500 copies/ml. In parallel testing of clinical specimens with low HIV-1 RNA levels, 80 plasma samples with <50 copies/ml by the US-RT-PCR assay had <50 copies/ml when they were retested by the bDNA 3.0 assay. In contrast, 11 of 78 (14%) plasma samples with <50 copies/ml by the bDNA 3.0 assay had ≥50 copies/ml when they were retested by the US-RT-PCR assay (median, 86 copies/ml; range, 50 to 217 copies/ml). Estimation of bDNA 3.0 values of <50 copies/ml by extending the standard curve of the assay showed that these samples with discrepant results had higher HIV-1 RNA levels than the samples with concordant results (median, 34 versus 17 copies/ml; P = 0.0051 by the Wilcoxon two-sample test). The excellent reproducibility, broad linear range, and good sensitivity of the bDNA 3.0 assay make it a very attractive method for quantitation of HIV-1 RNA levels in plasma. PMID:10921936

Model-based estimation for dynamic cardiac studies using ECT.

PubMed

Chiao, P C; Rogers, W L; Clinthorne, N H; Fessler, J A; Hero, A O

1994-01-01

The authors develop a strategy for joint estimation of physiological parameters and myocardial boundaries using ECT (emission computed tomography). They construct an observation model to relate parameters of interest to the projection data and to account for limited ECT system resolution and measurement noise. The authors then use a maximum likelihood (ML) estimator to jointly estimate all the parameters directly from the projection data without reconstruction of intermediate images. They also simulate myocardial perfusion studies based on a simplified heart model to evaluate the performance of the model-based joint ML estimator and compare this performance to the Cramer-Rao lower bound. Finally, the authors discuss model assumptions and potential uses of the joint estimation strategy.

Spatial design and strength of spatial signal: Effects on covariance estimation

USGS Publications Warehouse

Irvine, Kathryn M.; Gitelman, Alix I.; Hoeting, Jennifer A.

2007-01-01

In a spatial regression context, scientists are often interested in a physical interpretation of components of the parametric covariance function. For example, spatial covariance parameter estimates in ecological settings have been interpreted to describe spatial heterogeneity or “patchiness” in a landscape that cannot be explained by measured covariates. In this article, we investigate the influence of the strength of spatial dependence on maximum likelihood (ML) and restricted maximum likelihood (REML) estimates of covariance parameters in an exponential-with-nugget model, and we also examine these influences under different sampling designs—specifically, lattice designs and more realistic random and cluster designs—at differing intensities of sampling (n=144 and 361). We find that neither ML nor REML estimates perform well when the range parameter and/or the nugget-to-sill ratio is large—ML tends to underestimate the autocorrelation function and REML produces highly variable estimates of the autocorrelation function. The best estimates of both the covariance parameters and the autocorrelation function come under the cluster sampling design and large sample sizes. As a motivating example, we consider a spatial model for stream sulfate concentration.

A Laboratory Test for the Examination of Alactic Running Performance

PubMed Central

Kibele, Armin; Behm, David

2005-01-01

A new testing procedure is introduced to evaluate the alactic running performance in a 10s sprint task with near-maximal movement velocity. The test is performed on a motor-equipped treadmill with inverted polarity that increases mechanical resistance instead of driving the treadmill belt. As a result, a horizontal force has to be exerted against the treadmill surface in order to overcome the resistant force of the engine and to move the surface in a backward direction. For this task, subjects lean with their hands towards the front safety barrier of the treadmill railing with a slightly inclined body posture. The required skill resembles the pushing movement of bobsleigh pilots at the start of a race. Subjects are asked to overcome this mechanical resistance and to cover as much distance as possible within a time period of 10 seconds. Fifteen male students (age: 27.7 ± 4.1 years, body height: 1.82 ± 0.46 m, body mass: 78.3 ± 6.7 kg) participated in a study. As the resistance force was set to 134 N, subjects ran 35.4 ± 2.6 m on the average corresponding to a mean running velocity of 3.52 ± 0.25 m·s-1. The validity of the new test was examined by statistical inference with various measures related to alactic performance including a metabolic equivalent to estimate alactic capacity (2892 ± 525 mL O2), an estimate for the oxygen debt (2662 ± 315 ml), the step test by Margaria to estimate alactic energy flow (1691 ± 171 W), and a test to measure the maximal strength in the leg extensor muscles (2304 ± 351 N). The statistical evaluation showed that the new test is in good agreement with the theoretical assumptions for alactic performance. Significant correlation coefficients were found between the test criteria and the measures for alactic capacity (r = 0.79, p < 0.01) as well as alactic power (r = 0.77, p < 0.01). The testing procedure is easy to administer and it is best suited to evaluate the alactic capacity for bobsleigh pilots as well as for any other running discipline. Key Points New testing procedure for the evaluation of alactic running performance. 10s treadmill sprint task with near-maximal movement velocity similar to a bob sleigh start. Treadmill motor is used with inverted polarity to establish mechanical resistance rather than acceleration. Highly significant correlations found between test criteria and alactic performance measures. PMID:24501570

[Comparison of two cesarean techniques: classic versus Misgav Ladach cesarean].

PubMed

Moreira, P; Moreau, J C; Faye, M E; Ka, S; Kane Guèye, S M; Faye, E O; Dieng, T; Diadhiou, F

2002-10-01

The aim of the study was to compare two cesarean section techniques Methodology. A prospective study was conducted UB 400 cesareans performed at the Gynecological and Obstetric Clinic of the Dakar Teaching Hospital between March 2000 and August 2000. Two hundred patients underwent the classical procedure (CL group) and the other 200 the Misgav Ladach procedure (ML group). Per- and post-operative data were compared between the two groups with Student's test and the Chi(2) test. A p-value less than 0.05 was considered statistically significant. The two groups were similar for socio-demographic and clinical data. The delay between the skin incision and infant delivery was significantly shorter in the ML group (5 minutes 26 seconds versus 6 minutes 20 seconds). The same trend was found for the length of operation (36 minutes 36 seconds versus 54 minutes 38 seconds). Fewer sutures were used in the ML group (2.92 versus 4.14). There is no significant difference for dose of analgesia, post-operative complications and hospital discharge. Cost analysis demonstrated that the Misgav Ladach procedure was 10000 FCFA (15 euros) less costly. Misgav Ladach method is simple, rapid, cost-effective cesarean procedure which appears to be an attractive alternative to traditional cesarean section.

The Performance of ML, GLS, and WLS Estimation in Structural Equation Modeling under Conditions of Misspecification and Nonnormality.

ERIC Educational Resources Information Center

Olsson, Ulf Henning; Foss, Tron; Troye, Sigurd V.; Howell, Roy D.

2000-01-01

Used simulation to demonstrate how the choice of estimation method affects indexes of fit and parameter bias for different sample sizes when nested models vary in terms of specification error and the data demonstrate different levels of kurtosis. Discusses results for maximum likelihood (ML), generalized least squares (GLS), and weighted least…

Primary Fat Grafting to the Pectoralis Muscle during Latissimus Dorsi Breast Reconstruction

PubMed Central

Vidal, Luciano; Hersant, Barbara; Meningaud, Jean Paul

2016-01-01

Background: Latissimus dorsi flap is one of the best options for immediate and delayed breast reconstruction. However, this technique is limited by the tissue volume provided by the flap. To improve breast volume while reducing complications, fat grafting is now very often used in addition to latissimus dorsi flap. To the best of our knowledge, fat grafting was always performed as a second-line surgery, at least a few months after the flap procedure. We aimed to report our experience with an associated breast reconstruction technique combining musculocutaneous latissimus dorsi flap with intrapectoral lipofilling for totally autologous breast reconstruction. Methods: Between September 2014 and January 2015, 20 patients underwent this technique for unilateral autologous breast reconstruction (14 delayed and 6 immediate breast reconstructions). A mean harvested fat volume of 278 ml (range: 190–350 ml) and a mean injected fat volume of 228 ml (range: 170–280 ml) were used. Results: None of the patients experienced complications, such as flap necrosis, breast skin necrosis, hematomas, or infection. One of the patients developed a seroma, which was treated with 3 drainage punctions. Only 2 patients underwent delayed fat grafting procedure. Conclusion: Totally autologous breast reconstruction combining latissimus dorsi flap and intrapectoral fat grafting in the same procedure is a new technique allowing increased breast volume in a single surgery. PMID:27975006

A clean photometric method for the determination of losartan potassium in pharmaceuticals exploiting light scattering effect and employing a multicommuted flow analysis approach.

PubMed

Lima, Manoel J A; Reis, Boaventura F

2017-03-01

This paper describes an environmentally friendly procedure for the determination of losartan potassium (Los-K) in pharmaceuticals. The photometric method was based on the light scattering effect due to particles suspension, which were formed by the reaction of Los-K with Cu (II) ions. The method was automated employing a multicommuted flow analysis approach, implemented using solenoid mini-pumps for fluid propelling and a homemade LED based photometer. Under the optimized experimental conditions, the procedure showed a linear relationship in the concentration range of 23.2-417.6mgL -1 (r=0.9997, n=6), a relative standard deviation of 1.61% (n=10), a limit of detection (3.3*σ) estimated to be 12.1mgL -1 , and a sampling rate of 140 determinations per hour. Each determination consumed 12µg of copper (II) acetate and generated 0.54mL of waste. Copyright © 2016 Elsevier B.V. All rights reserved.

Estimation of Dynamic Discrete Choice Models by Maximum Likelihood and the Simulated Method of Moments

PubMed Central

Eisenhauer, Philipp; Heckman, James J.; Mosso, Stefano

2015-01-01

We compare the performance of maximum likelihood (ML) and simulated method of moments (SMM) estimation for dynamic discrete choice models. We construct and estimate a simplified dynamic structural model of education that captures some basic features of educational choices in the United States in the 1980s and early 1990s. We use estimates from our model to simulate a synthetic dataset and assess the ability of ML and SMM to recover the model parameters on this sample. We investigate the performance of alternative tuning parameters for SMM. PMID:26494926

Comparison of placebo and intrauterine lidocaine with/or without rectal diclofenac sodium suppositories used in office endometrial biopsy.

PubMed

Kaya, Cengiz; Sener, Elif Bengi; Koksal, Ersin; Ustun, Yasemin Burcu; Celik, Handan; Sahinoglu, Ali Haydar

2015-01-01

To compare the effects of intrauterine lidocaine, intrauterine lidocaine plus rectal diclofenac, and a placebo on analgesia and to determine the satisfaction of patients and surgeons in cases of endometrial biopsy. The double-blind, randomised, placebo-controlled study was conducted in the Department of Obstetrics and Gynaecology of the Ondokuz Mayis University, Samsun,Turkey, from April 2013 to January 2014, and comprised patients scheduled for in-office endometrial biopsy.They were divided into three groups: Group P, 5ml of 0.9% saline intrauterine; Group L, 5ml of 2% lidocaine intrauterine; and Group LD, 5ml of 2% lidocaine intrauterine ± 10min before the procedure plus 50mg of rectal diclofenac sodium. Haemodynamic changes and visual analogue scale scores were recorded during the preoperative period, when the cervix was grasped with a tenaculum, immediately after intrauterine instillation, during uterine curettage and at postoperative 10 min. The patient and the surgeon were questioned about their satisfaction 15 min after the procedure. SPSS 21 was used for statistical analysis. The 90 patients in the study were divided into three equal groups of 30(33.33%) each. There were no statistically significant inter-group differences in age, bodyweight, parity, number of postmenopausal patients, haemodynamic parameters and American Society of Anesthesiologists scores (p>0.05 in all categories). In Group P, the visual analogue scale score estimated when the cervix was grasped with the tenaculum was lower when compared with Group L and Group LD (p=0.029 and p=0.007, respectively). At other measurement time points, the scores did not differ between the groups. The groups did not differ with respect to patient and surgeon satisfaction and complication rates (p>0.05). Intrauterine lidocaine or intrauterine lidocaine plus rectal diclofenac application had no effect on visual analogue scale scores, patient satisfaction and vasovagal reaction.

Derivative Spectrophotometric Method for Estimation of Antiretroviral Drugs in Fixed Dose Combinations

PubMed Central

P.B., Mohite; R.B., Pandhare; S.G., Khanage

2012-01-01

Purpose: Lamivudine is cytosine and zidovudine is cytidine and is used as an antiretroviral agents. Both drugs are available in tablet dosage forms with a dose of 150 mg for LAM and 300 mg ZID respectively. Method: The method employed is based on first order derivative spectroscopy. Wavelengths 279 nm and 300 nm were selected for the estimation of the Lamovudine and Zidovudine respectively by taking the first order derivative spectra. The conc. of both drugs was determined by proposed method. The results of analysis have been validated statistically and by recovery studies as per ICH guidelines. Result: Both the drugs obey Beer’s law in the concentration range 10-50 μg mL-1,for LAM and ZID; with regression 0.9998 and 0.9999, intercept – 0.0677 and – 0.0043 and slope 0.0457 and 0.0391 for LAM and ZID, respectively.The accuracy and reproducibility results are close to 100% with 2% RSD. Conclusion: A simple, accurate, precise, sensitive and economical procedures for simultaneous estimation of Lamovudine and Zidovudine in tablet dosage form have been developed. PMID:24312779

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haseler, Luke J., E-mail: l.haseler@griffith.edu.au; Sibbitt, Randy R., E-mail: THESIBB2@aol.com; Sibbitt, Wilmer L., E-mail: wsibbitt@salud.unm.edu

Purpose: Syringes are used for diagnostic fluid aspiration and fine-needle aspiration biopsy in interventional procedures. We determined the benefits, disadvantages, and patient safety implications of syringe and needle size on vacuum generation, hand force requirements, biopsy/fluid yield, and needle control during aspiration procedures. Materials and Methods: Different sizes (1, 3, 5, 10, and 20 ml) of the conventional syringe and aspirating mechanical safety syringe, the reciprocating procedure device, were studied. Twenty operators performed aspiration procedures with the following outcomes measured: (1) vacuum (torr), (2) time to vacuum (s), (3) hand force to generate vacuum (torr-cm{sup 2}), (4) operator difficulty duringmore » aspiration, (5) biopsy yield (mg), and (6) operator control of the needle tip position (mm). Results: Vacuum increased tissue biopsy yield at all needle diameters (P < 0.002). Twenty-milliliter syringes achieved a vacuum of -517 torr but required far more strength to aspirate, and resulted in significant loss of needle control (P < 0.002). The 10-ml syringe generated only 15% less vacuum (-435 torr) than the 20-ml device and required much less hand strength. The mechanical syringe generated identical vacuum at all syringe sizes with less hand force (P < 0.002) and provided significantly enhanced needle control (P < 0.002). Conclusions: To optimize patient safety and control of the needle, and to maximize fluid and tissue yield during aspiration procedures, a two-handed technique and the smallest syringe size adequate for the procedure should be used. If precise needle control or one-handed operation is required, a mechanical safety syringe should be considered.« less

A novel approach to restore atrial function after the maze procedure in patients with an enlarged left atrium.

PubMed

Marui, Akira; Tambara, Keiichi; Tadamura, Eiji; Saji, Yoshiaki; Sasahashi, Nozomu; Ikeda, Tadashi; Nishina, Takeshi; Komeda, Masashi

2007-08-01

Left atrial (LA) volume reduction surgery concomitant with the maze procedure has been reported to facilitate sinus rhythm recovery even in patients with refractory atrial fibrillation (AF) with an enlarged LA. However, it is unknown whether the procedures can also restore effective atrial function of the enlarged LA with over-stretched myocardium. The maze procedures in association with mitral valve surgery were performed to 57 AF patients with an enlarged LA (LA diameter >or=60mm). Among them, 32 patients had concomitant LA volume reduction surgery (VR group). Another 25 patients did not have the volume reduction (control group). Three months postoperatively LA end-diastolic volume (LAEDV, ml) assessed by magnetic resonance (MR) imaging was larger in the VR group than that in the control group (291+/-117 vs 223+/-81 ml, p<0.05). Postoperatively, sinus rhythm recovery rate was better (84 vs 68%, p<0.05) and LAEDV was drastically smaller (118+/-48 vs 203+/-76 ml, p<0.001) in the VR group than those in the control group. Among the patients with sinus rhythm recovery in both groups, LA contraction ejection fraction (%) improved in the VR group but not in the control group (22.3+/-7.8 vs 10.3+/-4.7%, p<0.001). The LA volume reduction surgery concomitant with the maze procedure restored contraction of the enlarged LA; however, the maze procedure alone did not restore LA contraction in spite of successful sinus rhythm recovery. LA volume reduction surgery may be desirable to the patients with refractory AF with over-stretched LA.

Simultaneous Estimation of Amlodipine Besilate and Olmesartan Medoxomil in Pharmaceutical Dosage Form

PubMed Central

Wankhede, S. B.; Wadkar, S. B.; Raka, K. C.; Chitlange, S. S.

2009-01-01

Two UV Spectrophotometric and one reverse phase high performance liquid chromatography methods have been developed for the simultaneous estimation of amlodipine besilate and olmesartan medoxomil in tablet dosage form. First UV spectrophotometric method was a determination using the simultaneous equation method at 237.5 nm and 255.5 nm over the concentration range 10-50 μg/ml and 10-50 μg/ml, for amlodipine besilate and olmesartan medoxomil with accuracy 100.09%, and 100.22% respectively. Second UV spectrophotometric method was a determination using the area under curve method at 242.5-232.5 nm and 260.5-250.5 nm over the concentration range of 10-50 μg/ml and 10-50 μg/ml, for amlodipine besilate and olmesartan medoxomil with accuracy 100.10%, and 100.48%, respectively. In reverse phase high performance liquid chromatography analysis carried out using 0.05M potassuim dihydrogen phosphate buffer:acetonitrile (50:50 v/v) as the mobile phase and Kromasil C18 (4.6 mm i.d.×250 mm) column as the stationery phase with detection wavelength of 238 nm. Flow rate was 1.0 ml/min. Retention time for amlodipine besilate and olmesartan medoxomil were 3.69 and 5.36 min, respectively. Linearity was obtained in the concentration range of 4-20 μg/ml and 10-50 μg/ml for amlodipine besilate and olmesartan medoxomil, respectively. Proposed methods can be used for the estimation of amlodipine besilate and olmesartan medoxomil in tablet dosage form provided all the validation parameters are met. PMID:20502580

Gastrointestinal hemodynamics during compensation for hemorrhage and measurement of Pmcf.

PubMed

Rothe, C F; Maass-Moreno, R

1994-03-01

To quantify the degree of autonomic reflex control of the gastrointestinal vasculature, we studied the responses to a 10-ml/kg hemorrhage or transfusion and autonomic blockade in fentanyl- and pentobarbital-anesthetized dogs. The active total blood volume was estimated by indocyanine green dilution. Transfusion and hemorrhage did not significantly change gastrointestinal vascular compliance [1.82 +/- 0.68 (SD) ml/mmHg], but autonomic blockade with hexamethonium and atropine increased it by 0.57 +/- 0.37 ml/mmHg. Neither hemorrhage nor autonomic blockade significantly changed gastrointestinal vascular resistance from its control value of 10.8 +/- 4 mmHg.ml-1.min.kg body wt, but transfusion reduced it by 3.0 +/- 1.2 mmHg.ml-1.min.kg body wt. The ratio of gastrointestinal vascular resistance to total peripheral resistance was not significantly changed, however. We conclude that vascular compliance and resistance of the gastrointestinal bed are minimally influenced by the autonomic nervous system under the conditions studied. Portal pressure and flow measurements (transit-time ultrasound) during the above maneuvers were also combined with estimations of mean circulatory filling pressure (Pmcf) to test the hypothesis that, when the heart is stopped to measure Pmcf, portal pressure equals central venous pressure (Pcv) and hence that portal flow is zero. Seven seconds after the heart was stopped, portal venous pressure (Ppv) remained 0.83 +/- 0.78 mmHg higher than Pcv and portal flow decreased to only 25% of its control value. However, gastrointestinal compliance times (Ppv-Pcv), an estimate of the extra distending volume, was only 0.07 +/- 0.07 ml/kg body wt. Thus we conclude that the error in estimating Pmcf, given this (Ppv-Pcv) difference, is physiologically insignificant.

A single apheresis procedure in the donor may be enough to complete an allograft using the "Mexican method" of non-ablative allografting.

PubMed

Ruiz-Delgado, Guillermo J; Gutiérrez-Riveroll, Karla I; Gutiérrez-Aguirre, César H; Gómez-Almaguer, David; Eyzaguirre-Zapata, Renee; Priesca-Marin, Manuel; González-Carrillo, Martha L; Ruiz-Argüelles, Guillermo J

2009-04-01

Since 1999, in Mexico we have been using a regimen to conduct allografts that involves non-myeloablative conditioning and peripheral blood stem cells (PBSC) and have introduced some changes with the main goal of decreasing the cost of the procedure. We analysed the salient apheresis features of a group of 175 allogeneic peripheral blood stem cell transplants conducted in two institutions in a 7-year period. The grafts were conducted using the "Mexican" non-myelo ablative conditioning regimen employing oral busulphan, i.v. cyclophosphamide and i.v. fludarabine. In all instances, the apheresis machine employed was the Baxter CS3000 Plus and donors were mobilised with filgrastim. The apheresis procedures were performed on days 0, +1 and +2, the end-point of collection being 5,000 mL of blood/m2 in each procedure. Three apheresis sessions were planned but the number was adjusted according to the cell yield. The final number of allografted CD34 cells ranged between 0.5 and 25.4 x 10(6)/Kg of the recipient's body weight (median, 5.2 x 10(6)/Kg). One to three apheresis procedures were needed to obtain a product containing more than 0.5 x 10(6) CD34 cells/Kg of the recipient, the median being two procedures; in 72 cases (41%) a single apheresis procedure was sufficient to obtain the target number of CD34 cells. The volumes of apheresis ranged between 50 and 600 mL (median, 400 mL). Since the median cost of each apheresis procedure is 900 USD, the fact that two apheresis procedures was spared in 72 cases and one apheresis was spared in another 65 cases, led to a total saving of approximately 188,100 USD. It can be concluded that, in many cases, allogeneic transplants can be completed with a single apheresis session and that there are considerable financial benefits from this practice.

Risk factors for postoperative urinary tract infection following midurethral sling procedures.

PubMed

Doganay, Melike; Cavkaytar, Sabri; Kokanali, Mahmut Kuntay; Ozer, Irfan; Aksakal, Orhan Seyfi; Erkaya, Salim

2017-04-01

To identify the potential risk factors for urinary tract infections following midurethral sling procedures. 556 women who underwent midurethral sling procedure due to stress urinary incontinence over a four-year period were reviewed in this retrospective study. Of the study population, 280 women underwent TVT procedures and 276 women underwent TOT procedures. Patients were evaluated at 4-8 weeks postoperatively and were investigated for the occurrence of a urinary tract infection. Patients who experienced urinary tract infection were defined as cases, and patients who didn't were defined as controls. All data were collected from medical records. Multivariate logistic regression model was used to identify the risk factors for urinary tract infection. Of 556 women, 58 (10.4%) were defined as cases while 498 (89.6%) were controls. The mean age of women in cases (57.8±12.9years) was significantly greater than in controls (51.8±11.2years) (p<0.001). The presence of menopausal status, previous abdominal surgery, preoperative antibiotic treatment due to urinary tract infection, concomitant vaginal hysterectomy and cystocele repair, TVT procedure and postoperative postvoiding residual bladder volume ≥100ml were more common in cases than in controls. However, in multivariate regression analysis model presence of preoperative urinary tract infection [OR (95% CI)=0.1 (0.1-0.7); p=0.013], TVT procedure [OR (95% CI)=8.4 (3.1-22.3); p=0.000] and postoperative postvoiding residual bladder volume ≥100ml [OR (95% CI)=4.6 (1.1-19.2); p=0.036] were significant independent risk factors for urinary tract infection following midurethral slings CONCLUSION: Urinary tract infection after midurethral sling procedures is a relatively common complication. The presence of preoperative urinary tract infection, TVT procedure and postoperative postvoiding residual bladder volume ≥100ml may increase the risk of this complication. Identification of these factors could help surgeons to minimize this complicationby developing effective strategies. Copyright © 2017. Published by Elsevier B.V.

Photoselective vaporization of the prostate: the basel experience after 108 procedures.

PubMed

Bachmann, Alexander; Ruszat, Robin; Wyler, Stephen; Reich, Oliver; Seifert, Helge H; Müller, Alexander; Sulser, Tullio

2005-06-01

This study aims to investigate safety and efficacy of 80 watt high-power potassium titanyl phosphate (KTP) laser vaporization of the prostate in men with lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH). 108 patients underwent 80W KTP laser vaporization. Functional follow-up included measurement of maximum urinary flow rate (Qmax), postvoid residual volume (Vres) and International Prostate Symptom Score (IPSS) within a 12 months period. The average prostate volume was 52.2+/-24.3 ml and the preoperative PSA value was 3.6+/-3.6 ng/dl. Mean operation time was 54.5+/-25.0 min. Qmax increased highly significantly (p<0.001) by 111% (+7.9 ml/s) at discharge, 212% (+15.1 ml/s) after three months, 201% (+14.3 ml/s) after six months and 252% (+17.9 ml/s) after 12 months. Correspondingly, Vres, IPSS and Bother Score improved to an extent that was statistically highly significant (p<0.001) immediately after surgery. The observed complication rate within one year was low. 80 W KTP laser vaporization is a virtually bloodless, safe and effective procedure for surgical treatment of LUTS secondary to BPH. A significant improvement of objective and subjective voiding parameters was observed just after surgery. KTP laser vaporization is associated with a low rate of complications.

Magnetic nanoparticle-enhanced PCR for the detection and identification of Staphylococcus aureus and Salmonella enteritidis.

PubMed

Houhoula, Dimitra; Papaparaskevas, Joseph; Zatsou, Katerina; Nikolaras, Nikolaos; Malkawi, Hanan I; Mingenot-Leclercq, Marie-Paule; Konteles, Spyros; Koussisis, Stamatis; Tsakris, Athanassios; Charvalos, Ekatherina

2017-07-01

This paper evaluated magnetic nanoparticle-enhanced PCR for the detection and identification of Staphylococcus aureus and Salmonella enteritidis. Two different types of magnetic nanoparticles designated MPIO (iron concentration 2.5 mg/ml, size 1 µm) and NP (iron concentration 8.7 mg/ml, size 60 nm), both conjugated with S. aureus or S. enteritidis antibodies were evaluated as an enrichment procedure for PCR-detection of the pathogens in Trypticase Soy Broth, milk, blood and meat broth. Bacterial suspensions (1.5x108 cfu/ml) were prepared and serial diluted 10-1. The MPIO and NP nanoparticles were added, followed by incubation for 1 hour at room temperature, magnetic separation of the pellet, DNA extraction and PCR, targeting the femA and invA sequences. The nanoparticle-free and the NP-supplemented dilutions were positive down to the 1.5x102 cfu/ml concentration for both bacteria. The MPIO-supplemented dilutions were positive down to approx. 2x100 cfu/ml concentration, respectively. Bacteria-free TSB was negative by PCR. MPIO nanoparticles (size 1 µm) enhanced the detection of S. aureus and S. enteritidis by PCR, whilst NP nanoparticles (size 60 nm) did not, thus indicating that the size of the magnetic nanoparticles play a significant role in the enrichment procedure.

Target-controlled infusion of remifentanil with or without flurbiprofen axetil in sedation for extracorporeal shock wave lithotripsy of pancreatic stones: a prospective, open-label, randomized controlled trial.

PubMed

Yang, Yu-Guang; Hu, Liang-Hao; Chen, Hui; Li, Bo; Fan, Xiao-Hua; Li, Jin-Bao; Wang, Jia-Feng; Deng, Xiao-Ming

2015-11-07

Extracorporeal shock wave lithotripsy (ESWL) is an effective therapeutic method used to treat patients with pancreatic stones. However, the anesthesia for this procedure has been underappreciated, with minimal reports of these procedures in certain case series with general or epidural anesthesia. A cohort of 60 patients who elected to undergo ESWL in order to treat pancreatic stones for the first time were randomly selected and divided into two groups. One group of patients received target controlled infusion (TCI) of remifentanil, while the other group of patients received TCI of remifentanil plus a bolus of flurbiprofen axetil (a cyclooxygenase inhibitor) (Rem group and Rem + Flu group, n = 30 for each group). The Dixon's up-and-down method was used to calculate the half maximum effective concentration (EC50) of remifentanil. Visual analogue scales of pain, Ramsay sedation scale, hemodynamic changes, and adverse events were also recorded. The EC50 of remifentanil was calculated to be 4.0 ng/ml (95 % confidential interval: 3.84 ng/ml, 4.16 ng/ml) and 2.76 ng/ml (95 % confidential interval: 2.63 ng/ml, 2.89 ng/ml) in the Rem group and Rem + Flu group respectively (p < 0.001). Pain score was comparable between the two groups, while the Ramsay sedation scale was higher in the Rem group. Hemodynamic data showed that patients in the Rem group experienced higher mean arterial pressures and higher heart rates across the procedures. Patients in Rem group demonstrated a lower respiratory rate (p < 0.001) and a lower SpO2 (p = 0.001). Less adverse events occurred in Rem + Flu group, including a reduced respiratory depression requiring wake-up as well as reduced postoperative nausea and vomiting. Remifentanil plus flurbiprofen axetil provided satisfactory analgesia and sedation for ESWL of pancreatic stones with less adverse events. (Clinicaltrial.gov: NCT01998217 ; registered on November 19, 2013).

Portable Language-Independent Adaptive Translation from OCR. Phase 1

DTIC Science & Technology

2009-04-01

including brute-force k-Nearest Neighbors ( kNN ), fast approximate kNN using hashed k-d trees, classification and regression trees, and locality...achieved by refinements in ground-truthing protocols. Recent algorithmic improvements to our approximate kNN classifier using hashed k-D trees allows...recent years discriminative training has been shown to outperform phonetic HMMs estimated using ML for speech recognition. Standard ML estimation

A comparison of the original Rappaport medium (R medium) and the Rappaport-Vassiliadis medium (RV medium) in the isolation of salmonellae from meat products.

PubMed Central

Vassiliadis, P.; Kalapothaki, V.; Mavrommati, C.; Trichopoulos, D.

1984-01-01

The Rappaport-Vassiliadis enrichment medium (RV medium) in 10 ml quantities (RV/43 degrees C, 10 ml) inoculated with 0.1 ml of pre-enrichment medium (P medium) was found more efficient in the isolation of salmonellae from 409 pre-enriched samples (mainly meat products), than the original Rappaport medium incubated at 43 degrees C (R/43 degrees C) and the RV medium in 5 ml quantities (RV/43 degrees C, 5 ml) inoculated with 0.01 ml of P medium (P less than 0.001, in both instances). Therefore, the inoculum from pre-enriched foods should not be less than 0.1 ml in 10 ml of RV medium. The RV/43 degrees, 10 ml was also better (P less than 0.01) in detecting samples containing salmonellas than the original Rappaport medium incubated at 37 degrees C (R/37 degrees C, 10 ml) and the modification R25 of R medium incubated at 37 degrees C. The R25 modification was used in 10 ml quantities (R25/37 degrees C, 10 ml) inoculated with 0.1 ml of P medium and in 5 ml quantities (R25/37 degrees, 5 ml) inoculated with 0.01 ml of P medium. The last two R25 procedures were of the same efficiency in isolating salmonellas from meat products. PMID:6747286

The efficiency of therapeutic erythrocytapheresis compared to phlebotomy: a mathematical tool for predicting response in hereditary hemochromatosis, polycythemia vera, and secondary erythrocytosis.

PubMed

Evers, Dorothea; Kerkhoffs, Jean-Louis; Van Egmond, Liane; Schipperus, Martin R; Wijermans, Pierre W

2014-06-01

Recently, therapeutic erythrocytapheresis (TE) was suggested to be more efficient in depletion of red blood cells (RBC) compared to manual phlebotomy in the treatment of hereditary hemochromatosis (HH), polycythemia vera (PV), and secondary erythrocytosis (SE). The efficiency rate (ER) of TE, that is, the increase in RBC depletion achieved with one TE cycle compared to one phlebotomy procedure, can be calculated based on estimated blood volume (BV), preprocedural hematocrit (Hct(B)), and delta-hematocrit (ΔHct). In a retrospective evaluation of 843 TE procedures (in 45 HH, 33 PV, and 40 SE patients) the mean ER was 1.86 ± 0.62 with the highest rates achieved in HH patients. An ER of 1.5 was not reached in 37.9% of all procedures mainly concerning patients with a BV below 4,500 ml. In 12 newly diagnosed homozygous HH patients, the induction phase duration was medially 38.4 weeks (medially 10.5 procedures). During the maintenance treatment of HH, PV, and SE, the interval between TE procedures was medially 13.4 weeks. This mathematical model can help select the proper treatment modality for the individual patient. Especially for patients with a large BV and high achievable ΔHct, TE appears to be more efficient than manual phlebotomy in RBC depletion thereby potentially reducing the numbers of procedures and expanding the interprocedural time period for HH, PV, and SE. © 2013 Wiley Periodicals, Inc.

Model-based estimation for dynamic cardiac studies using ECT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chiao, P.C.; Rogers, W.L.; Clinthorne, N.H.

1994-06-01

In this paper, the authors develop a strategy for joint estimation of physiological parameters and myocardial boundaries using ECT (Emission Computed Tomography). The authors construct an observation model to relate parameters of interest to the projection data and to account for limited ECT system resolution and measurement noise. The authors then use a maximum likelihood (ML) estimator to jointly estimate all the parameters directly from the projection data without reconstruction of intermediate images. The authors also simulate myocardial perfusion studies based on a simplified heart model to evaluate the performance of the model-based joint ML estimator and compare this performancemore » to the Cramer-Rao lower bound. Finally, model assumptions and potential uses of the joint estimation strategy are discussed.« less

Multicenter Comparative Evaluation of Five Commercial Methods for Toxoplasma DNA Extraction from Amniotic Fluid▿

PubMed Central

Yera, H.; Filisetti, D.; Bastien, P.; Ancelle, T.; Thulliez, P.; Delhaes, L.

2009-01-01

Over the past few years, a number of new nucleic acid extraction methods and extraction platforms using chemistry combined with magnetic or silica particles have been developed, in combination with instruments to facilitate the extraction procedure. The objective of the present study was to investigate the suitability of these automated methods for the isolation of Toxoplasma gondii DNA from amniotic fluid (AF). Therefore, three automated procedures were compared to two commercialized manual extraction methods. The MagNA Pure Compact (Roche), BioRobot EZ1 (Qiagen), and easyMAG (bioMérieux) automated procedures were compared to two manual DNA extraction kits, the QIAamp DNA minikit (Qiagen) and the High Pure PCR template preparation kit (Roche). Evaluation was carried out with two specific Toxoplasma PCRs (targeting the 529-bp repeat element), inhibitor search PCRs, and human beta-globin PCRs. The samples each consisted of 4 ml of AF with or without a calibrated Toxoplasma gondii RH strain suspension (0, 1, 2.5, 5, and 25 tachyzoites/ml). All PCR assays were laboratory-developed real-time PCR assays, using either TaqMan or fluorescent resonance energy transfer probes. A total of 1,178 PCRs were performed, including 978 Toxoplasma PCRs. The automated and manual methods were similar in sensitivity for DNA extraction from T. gondii at the highest concentration (25 Toxoplasma gondii cells/ml). However, our results showed that the DNA extraction procedures led to variable efficacy in isolating low concentrations of tachyzoites in AF samples (<5 Toxoplasma gondii cells/ml), a difference that might have repercussions since low parasite concentrations in AF exist and can lead to congenital toxoplasmosis. PMID:19846633

Physiology Laboratories Quantifying Gas Exchange in Health and Disease.

ERIC Educational Resources Information Center

Olson, L. E.

1985-01-01

Describes two quantitatively-oriented physiology laboratories for veterinary students. The laboratory exercises incorporate the procedures of radiology and physical examination with measurement of pulmonary function. Specific laboratory objectives, procedures and equipment needed for diagnoses of the pathologies are listed. (ML)

A signal-amplified electrochemical DNA biosensor incorporated with a colorimetric internal control for Vibrio cholerae detection using shelf-ready reagents.

PubMed

Low, Kim-Fatt; Zain, Zainiharyati Mohd; Yean, Chan Yean

2017-01-15

A novel enzyme/nanoparticle-based DNA biosensing platform with dual colorimetric/electrochemical approach has been developed for the sequence-specific detection of the bacterium Vibrio cholerae, the causative agent of acute diarrheal disease in cholera. This assay platform exploits the use of shelf-stable and ready-to-use (shelf-ready) reagents to greatly simplify the bioanalysis procedures, allowing the assay platform to be more amenable to point-of-care applications. To assure maximum diagnosis reliability, an internal control (IC) capable of providing instant validation of results was incorporated into the assay. The microbial target, single-stranded DNA amplified with asymmetric PCR, was quantitatively detected via electrochemical stripping analysis of gold nanoparticle-loaded latex microspheres as a signal-amplified hybridization tag, while the incorporated IC was analyzed using a simplified horseradish peroxidase enzyme-based colorimetric scheme by simple visual observation of enzymatic color development. The platform showed excellent diagnostic sensitivity and specificity (100%) when challenged with 145 clinical isolate-spiked fecal specimens. The limits of detection were 0.5ng/ml of genomic DNA and 10 colony-forming units (CFU)/ml of bacterial cells with dynamic ranges of 0-100ng/ml (R 2 =0.992) and log 10 (1-10 4 CFU/ml) (R 2 =0.9918), respectively. An accelerated stability test revealed that the assay reagents were stable at temperatures of 4-37°C, with an estimated ambient shelf life of 200 days. The versatility of the biosensing platform makes it easily adaptable for quantitative detection of other microbial pathogens. Copyright © 2016 Elsevier B.V. All rights reserved.

Evaluation of the rabbit liver by direct portography and contrast-enhanced computed tomography: anatomical variations of the portal system and hepatic volume quantification.

PubMed

Páramo, María; García-Barquin, Paula; Santa María, Eva; Madrid, José Miguel; Caballeros, Meylin; Benito, Alberto; Sangro, Bruno; Iñarrairaegui, Mercedes; Bilbao, José Ignacio

2017-01-01

The study was aimed at: (1) describing the incidence of anatomic variations of the portal system in the rabbit using direct portography; and (2) estimating the liver volume and caudate lobe volume by using contrast-enhanced computed tomography (CECT) in the same animal model. Forty-six New Zealand white rabbits were included. All of them underwent direct portography and unenhanced CECT. Conventional liver rabbit portal system anatomy (type 1) consisted of the bifurcation of the main portal vein (MPV) into the right portal vein (RPV) and left portal vein (LPV), which subsequently divided into medial left portal vein and lateral left portal vein. Trifurcation of the LPV was considered type 2. The LPV that divides into four smaller branches was classified as type 3. Other configurations of the portal system, including particular cases of MPV branching, were grouped as type 4. Liver lobes were manually segmented. The incidence of each type of portal system anatomy was: type 1, 67.4%; type 2, 15.2%; type 3, 13.0%); and type 4, 4.3%. The mean volume of the caudate lobe was 19.1 ml ± 5.7 ml and of the cranial lobes it was 66.7 ml ± 13.7 ml, and the total liver volume was 85.7 ml ± 16.7 ml. In New Zealand white rabbits, type 1 is the prevalent type of portal system, liver volume is about 86 ml, and the caudate and cranial lobes are separated. This information could be important when planning experimental rabbit liver procedures.

Outcomes of minimally invasive simple prostatectomy for benign prostatic hyperplasia: a systematic review and meta-analysis.

PubMed

Lucca, Ilaria; Shariat, Shahrokh F; Hofbauer, Sebastian L; Klatte, Tobias

2015-04-01

(1) To assess the outcomes of minimally invasive simple prostatectomy (MISP) for the treatment of symptomatic benign prostatic hyperplasia in men with large prostates and (2) to compare them with open simple prostatectomy (OSP). A systematic review of outcomes of MISP for benign prostatic hyperplasia with meta-analysis was conducted. The article selection process was conducted according to the PRISMA guidelines. Twenty-seven observational studies with 764 patients were analyzed. The mean prostate volume was 113.5 ml (95 % CI 106-121). The mean increase in Qmax was 14.3 ml/s (95 % CI 13.1-15.6), and the mean improvement in IPSS was 17.2 (95 % CI 15.2-19.2). Mean duration of operation was 141 min (95 % CI 124-159), and the mean intraoperative blood loss was 284 ml (95 % CI 243-325). One hundred and four patients (13.6 %) developed a surgical complication. In comparative studies, length of hospital stay (WMD -1.6 days, p = 0.02), length of catheter use (WMD -1.3 days, p = 0.04) and estimated blood loss (WMD -187 ml, p = 0.015) were significantly lower in the MISP group, while the duration of operation was longer than in OSP (WMD 37.8 min, p < 0.0001). There were no differences in improvements in Qmax, IPSS and perioperative complications between both procedures. The small study sizes, publication bias, lack of systematic complication reporting and short follow-up are limitations. MISP seems an effective and safe treatment option. It provides similar improvements in Qmax and IPSS as OSP. Despite taking longer, it results in less blood loss and shorter hospital stay. Prospective randomized studies comparing OSP, MISP and laser enucleation are needed to define the standard surgical treatment for large prostates.

Cefazolin pharmacokinetics in cats under surgical conditions.

PubMed

Albarellos, Gabriela A; Montoya, Laura; Passini, Sabrina M; Lupi, Martín P; Lorenzini, Paula M; Landoni, María F

2017-10-01

Objectives The aim of this study was to determine the plasma pharmacokinetic profile, tissue concentrations and urine elimination of cefazolin in cats under surgical conditions after a single intravenous dose of 20 mg/kg. Methods Intravenous cefazolin (20 mg/kg) was administered to nine young mixed-breed cats 30 mins before they underwent surgical procedures (ovariectomy or orchiectomy). After antibiotic administration, samples from blood, some tissues and urine were taken. Cefazolin concentrations were determined in all biological matrices and pharmacokinetic parameters were estimated. Results Initial plasma concentrations were high (C p(0) , 134.80 ± 40.54 µg/ml), with fast and moderately wide distribution (distribution half-life [t ½(d) ] 0.16 ± 0.15 h; volume of distribution at steady state [V (d[ss]) ] 0.29 ± 0.10 l/kg) and rapid elimination (body clearance [Cl B ], 0.21 ± 0.06 l/h/kg; elimination half-life [t ½ ], 1.18 ± 0.27 h; mean residence time 1.42 ± 0.36 h). Thirty to 60 mins after intravenous administration, cefazolin tissue concentrations ranged from 9.24 µg/ml (subcutaneous tissue) to 26.44 µg/ml (ovary). The tissue/plasma concentration ratio ranged from 0.18 (muscle) to 0.58 (ovary). Cefazolin urine concentrations were high with 84.2% of the administered dose being eliminated in the first 6 h postadministration. Conclusions and relevance Cefazolin plasma concentrations remained above a minimum inhibitory concentration of ⩽2 µg/ml up to 4 h in all the studied cats. This suggests that a single intravenous dose of 20 mg/kg cefazolin would be adequate for perioperative prophylactic use in cats.

Plane-dependent ML scatter scaling: 3D extension of the 2D simulated single scatter (SSS) estimate

NASA Astrophysics Data System (ADS)

Rezaei, Ahmadreza; Salvo, Koen; Vahle, Thomas; Panin, Vladimir; Casey, Michael; Boada, Fernando; Defrise, Michel; Nuyts, Johan

2017-08-01

Scatter correction is typically done using a simulation of the single scatter, which is then scaled to account for multiple scatters and other possible model mismatches. This scaling factor is determined by fitting the simulated scatter sinogram to the measured sinogram, using only counts measured along LORs that do not intersect the patient body, i.e. ‘scatter-tails’. Extending previous work, we propose to scale the scatter with a plane dependent factor, which is determined as an additional unknown in the maximum likelihood (ML) reconstructions, using counts in the entire sinogram rather than only the ‘scatter-tails’. The ML-scaled scatter estimates are validated using a Monte-Carlo simulation of a NEMA-like phantom, a phantom scan with typical contrast ratios of a 68Ga-PSMA scan, and 23 whole-body 18F-FDG patient scans. On average, we observe a 12.2% change in the total amount of tracer activity of the MLEM reconstructions of our whole-body patient database when the proposed ML scatter scales are used. Furthermore, reconstructions using the ML-scaled scatter estimates are found to eliminate the typical ‘halo’ artifacts that are often observed in the vicinity of high focal uptake regions.

A machine learning approach as a surrogate of finite element analysis-based inverse method to estimate the zero-pressure geometry of human thoracic aorta.

PubMed

Liang, Liang; Liu, Minliang; Martin, Caitlin; Sun, Wei

2018-05-09

Advances in structural finite element analysis (FEA) and medical imaging have made it possible to investigate the in vivo biomechanics of human organs such as blood vessels, for which organ geometries at the zero-pressure level need to be recovered. Although FEA-based inverse methods are available for zero-pressure geometry estimation, these methods typically require iterative computation, which are time-consuming and may be not suitable for time-sensitive clinical applications. In this study, by using machine learning (ML) techniques, we developed an ML model to estimate the zero-pressure geometry of human thoracic aorta given 2 pressurized geometries of the same patient at 2 different blood pressure levels. For the ML model development, a FEA-based method was used to generate a dataset of aorta geometries of 3125 virtual patients. The ML model, which was trained and tested on the dataset, is capable of recovering zero-pressure geometries consistent with those generated by the FEA-based method. Thus, this study demonstrates the feasibility and great potential of using ML techniques as a fast surrogate of FEA-based inverse methods to recover zero-pressure geometries of human organs. Copyright © 2018 John Wiley & Sons, Ltd.

Optimization and Interpretation of Serial QuantiFERON Testing to Measure Acquisition of Mycobacterium tuberculosis Infection.

PubMed

Nemes, Elisa; Rozot, Virginie; Geldenhuys, Hennie; Bilek, Nicole; Mabwe, Simbarashe; Abrahams, Deborah; Makhethe, Lebohang; Erasmus, Mzwandile; Keyser, Alana; Toefy, Asma; Cloete, Yolundi; Ratangee, Frances; Blauenfeldt, Thomas; Ruhwald, Morten; Walzl, Gerhard; Smith, Bronwyn; Loxton, Andre G; Hanekom, Willem A; Andrews, Jason R; Lempicki, Maria D; Ellis, Ruth; Ginsberg, Ann M; Hatherill, Mark; Scriba, Thomas J

2017-09-01

Conversion from a negative to positive QuantiFERON-TB test is indicative of Mycobacterium tuberculosis (Mtb) infection, which predisposes individuals to tuberculosis disease. Interpretation of serial tests is confounded by immunological and technical variability. To improve the consistency of serial QuantiFERON-TB testing algorithms and provide a data-driven definition of conversion. Sources of QuantiFERON-TB variability were assessed, and optimal procedures were identified. Distributions of IFN-γ response levels were analyzed in healthy adolescents, Mtb-unexposed control subjects, and patients with pulmonary tuberculosis. Individuals with no known Mtb exposure had IFN-γ values less than 0.2 IU/ml. Among individuals with IFN-γ values less than 0.2 IU/ml, 0.2-0.34 IU/ml, 0.35-0.7 IU/ml, and greater than 0.7 IU/ml, tuberculin skin test positivity results were 15%, 53%, 66%, and 91% (P < 0.005), respectively. Together, these findings suggest that values less than 0.2 IU/ml were true negatives. In short-term serial testing, "uncertain" conversions, with at least one value within the uncertainty zone (0.2-0.7 IU/ml), were partly explained by technical assay variability. Individuals who had a change in QuantiFERON-TB IFN-γ values from less than 0.2 to greater than 0.7 IU/ml had 10-fold higher tuberculosis incidence rates than those who maintained values less than 0.2 IU/ml over 2 years (P = 0.0003). By contrast, "uncertain" converters were not at higher risk than nonconverters (P = 0.229). Eighty-seven percent of patients with active tuberculosis had IFN-γ values greater than 0.7 IU/ml, suggesting that these values are consistent with established Mtb infection. Implementation of optimized procedures and a more rigorous QuantiFERON-TB conversion definition (an increase from IFN-γ <0.2 to >0.7 IU/ml) would allow more definitive detection of recent Mtb infection and potentially improve identification of those more likely to develop disease.

BindML/BindML+: Detecting Protein-Protein Interaction Interface Propensity from Amino Acid Substitution Patterns.

PubMed

Wei, Qing; La, David; Kihara, Daisuke

2017-01-01

Prediction of protein-protein interaction sites in a protein structure provides important information for elucidating the mechanism of protein function and can also be useful in guiding a modeling or design procedures of protein complex structures. Since prediction methods essentially assess the propensity of amino acids that are likely to be part of a protein docking interface, they can help in designing protein-protein interactions. Here, we introduce BindML and BindML+ protein-protein interaction sites prediction methods. BindML predicts protein-protein interaction sites by identifying mutation patterns found in known protein-protein complexes using phylogenetic substitution models. BindML+ is an extension of BindML for distinguishing permanent and transient types of protein-protein interaction sites. We developed an interactive web-server that provides a convenient interface to assist in structural visualization of protein-protein interactions site predictions. The input data for the web-server are a tertiary structure of interest. BindML and BindML+ are available at http://kiharalab.org/bindml/ and http://kiharalab.org/bindml/plus/ .

An Investigation of the Sample Performance of Two Nonnormality Corrections for RMSEA

ERIC Educational Resources Information Center

Brosseau-Liard, Patricia E.; Savalei, Victoria; Li, Libo

2012-01-01

The root mean square error of approximation (RMSEA) is a popular fit index in structural equation modeling (SEM). Typically, RMSEA is computed using the normal theory maximum likelihood (ML) fit function. Under nonnormality, the uncorrected sample estimate of the ML RMSEA tends to be inflated. Two robust corrections to the sample ML RMSEA have…

Optimal effect-site concentration of remifentanil when combined with dexmedetomidine in patients undergoing cystoscopy

PubMed Central

Heo, Bongha; Kim, Minsun; Lee, Hyunjung; Park, Sanghee

2014-01-01

Background Cystoscopic procedure is a very common practice in the field of urology due to its ability to survey the bladder for a variety of indications. However, patients who undergo cystoscopy feel intense pain and discomfort. This study investigated the half maximal effective concentration (EC50) of remifentanil in preventing cystoscope insertion pain under sedation using dexmedetomidine. Methods The study was prospectively conducted on 18 male patients, aged 18 to 65. Remifentail infusion was initiated together with dexmedetomidine, and started at a dose of 2.4 ng/ml on the first patient. The effect-site concentration (Ce) of remifentanil for each subsequent patient was determined by the previous patient's response using Dixon's up-and-down method with an interval of 0.3 ng/ml. Patients received a loading dose of 1.0 µg/kg dexmedetomidine over 10 minutes, followed by a maintenance dose of 0.6 µg/kg/hr. After the patient's OAA/S score (Observer's Assessment of Alertness/Sedation scale) reached 3-4, and the Ce of remifentanil reached target concentration, the urologist was allowed to insert the cystoscope and the pain responses were observed. Results The effect-site concentration of remifentanil required to prevent cystoscope insertion pain in 50% of patients under sedation using dexmedetomidine was 1.30 ± 0.12 ng/ml by Dixon's up-and-down method. The logistic regression curve of the probability of response showed that the EC50 and EC95 values (95% confidence limits) of remifentanil were 1.33 ng/ml (1.12-1.52 ng/ml) and 1.58 ng/ml (1.44-2.48 ng/ml), respectively. Conclusions Cystoscopic procedure can be carried out successfully without any pain or adverse effects by optimal remifentanil effect-site concentration (EC50, 1.33 ng/ml; EC95, 1.58 ng/ ml) combined with sedation using dexmedetomidine. PMID:24567812

ART-ML: a new markup language for modelling and representation of biological processes in cardiovascular diseases.

PubMed

Karvounis, E C; Exarchos, T P; Fotiou, E; Sakellarios, A I; Iliopoulou, D; Koutsouris, D; Fotiadis, D I

2013-01-01

With an ever increasing number of biological models available on the internet, a standardized modelling framework is required to allow information to be accessed and visualized. In this paper we propose a novel Extensible Markup Language (XML) based format called ART-ML that aims at supporting the interoperability and the reuse of models of geometry, blood flow, plaque progression and stent modelling, exported by any cardiovascular disease modelling software. ART-ML has been developed and tested using ARTool. ARTool is a platform for the automatic processing of various image modalities of coronary and carotid arteries. The images and their content are fused to develop morphological models of the arteries in 3D representations. All the above described procedures integrate disparate data formats, protocols and tools. ART-ML proposes a representation way, expanding ARTool, for interpretability of the individual resources, creating a standard unified model for the description of data and, consequently, a format for their exchange and representation that is machine independent. More specifically, ARTool platform incorporates efficient algorithms which are able to perform blood flow simulations and atherosclerotic plaque evolution modelling. Integration of data layers between different modules within ARTool are based upon the interchange of information included in the ART-ML model repository. ART-ML provides a markup representation that enables the representation and management of embedded models within the cardiovascular disease modelling platform, the storage and interchange of well-defined information. The corresponding ART-ML model incorporates all relevant information regarding geometry, blood flow, plaque progression and stent modelling procedures. All created models are stored in a model repository database which is accessible to the research community using efficient web interfaces, enabling the interoperability of any cardiovascular disease modelling software models. ART-ML can be used as a reference ML model in multiscale simulations of plaque formation and progression, incorporating all scales of the biological processes.

Causal mediation analysis with a binary outcome and multiple continuous or ordinal mediators: Simulations and application to an alcohol intervention

PubMed Central

Nguyen, Trang Quynh; Webb-Vargas, Yenny; Koning, Ina M.; Stuart, Elizabeth A.

2016-01-01

We investigate a method to estimate the combined effect of multiple continuous/ordinal mediators on a binary outcome: 1) fit a structural equation model with probit link for the outcome and identity/probit link for continuous/ordinal mediators, 2) predict potential outcome probabilities, and 3) compute natural direct and indirect effects. Step 2 involves rescaling the latent continuous variable underlying the outcome to address residual mediator variance/covariance. We evaluate the estimation of risk-difference- and risk-ratio-based effects (RDs, RRs) using the ML, WLSMV and Bayes estimators in Mplus. Across most variations in path-coefficient and mediator-residual-correlation signs and strengths, and confounding situations investigated, the method performs well with all estimators, but favors ML/WLSMV for RDs with continuous mediators, and Bayes for RRs with ordinal mediators. Bayes outperforms WLSMV/ML regardless of mediator type when estimating RRs with small potential outcome probabilities and in two other special cases. An adolescent alcohol prevention study is used for illustration. PMID:27158217

Thermal dye double indicator dilution measurement of lung water in man: comparison with gravimetric measurements.

PubMed Central

Mihm, F G; Feeley, T W; Jamieson, S W

1987-01-01

The thermal dye double indicator dilution technique for estimating lung water was compared with gravimetric analyses in nine human subjects who were organ donors. As observed in animal studies, the thermal dye measurement of extravascular thermal volume (EVTV) consistently overestimated gravimetric extravascular lung water (EVLW), the mean (SEM) difference being 3.43 (0.59) ml/kg. In eight of the nine subjects the EVTV -3.43 ml/kg would yield an estimate of EVLW that would be from 3.23 ml/kg under to 3.37 ml/kg over the actual value EVLW at the 95% confidence limits. Reproducibility, assessed with the standard error of the mean percentage, suggested that a 15% change in EVTV can be reliably detected with repeated measurements. One subject was excluded from analysis because the EVTV measurement grossly underestimated its actual EVLW. This error was associated with regional injury observed on gross examination of the lung. Experimental and clinical evidence suggest that the thermal dye measurement provides a reliable estimate of lung water in diffuse pulmonary oedema states. PMID:3616974

Maximum likelihood orientation estimation of 1-D patterns in Laguerre-Gauss subspaces.

PubMed

Di Claudio, Elio D; Jacovitti, Giovanni; Laurenti, Alberto

2010-05-01

A method for measuring the orientation of linear (1-D) patterns, based on a local expansion with Laguerre-Gauss circular harmonic (LG-CH) functions, is presented. It lies on the property that the polar separable LG-CH functions span the same space as the 2-D Cartesian separable Hermite-Gauss (2-D HG) functions. Exploiting the simple steerability of the LG-CH functions and the peculiar block-linear relationship among the two expansion coefficients sets, maximum likelihood (ML) estimates of orientation and cross section parameters of 1-D patterns are obtained projecting them in a proper subspace of the 2-D HG family. It is shown in this paper that the conditional ML solution, derived by elimination of the cross section parameters, surprisingly yields the same asymptotic accuracy as the ML solution for known cross section parameters. The accuracy of the conditional ML estimator is compared to the one of state of art solutions on a theoretical basis and via simulation trials. A thorough proof of the key relationship between the LG-CH and the 2-D HG expansions is also provided.

Automatic picker of P & S first arrivals and robust event locator

NASA Astrophysics Data System (ADS)

Pinsky, V.; Polozov, A.; Hofstetter, A.

2003-12-01

We report on further development of automatic all distances location procedure designed for a regional network. The procedure generalizes the previous "loca l" (R < 500 km) and "regional" (500 < R < 2000 km) routines and comprises: a) preliminary data processing (filtering and de-spiking), b) phase identificatio n, c) P, S first arrival picking, d) preliminary location and e) robust grid-search optimization procedure. Innovations concern phase identification, automa tic picking and teleseismic location. A platform free flexible Java interface was recently created, allowing easy parameter tuning and on/off switching to t he full-scale manual picking mode. Identification of the regional P and S phase is provided by choosing between the two largest peaks in the envelope curve. For automatic on-time estimation we utilize now ratio of two STAs, calculated in two consecutive and equal time windows (instead of previously used Akike Information Criterion). "Teleseismic " location is split in two stages: preliminary and final one. The preliminary part estimates azimuth and apparent velocity by fitting a plane wave to the P automatic pickings. The apparent velocity criterion is used to decide about strategy of the following computations: teleseismic or regional. The preliminary estimates of azimuth and apparent velocity provide starting value for the final teleseismic and regional location. Apparent velocity is used to get first a pproximation distance to the source on the basis of the P, Pn, Pg travel-timetables. The distance estimate together with the preliminary azimuth estimate provides first approximations of the source latitude and longitude via sine and cosine theorems formulated for the spherical triangle. Final location is based on robust grid-search optimization procedure, weighting the number of pickings that simultaneously fit the model travel times. The grid covers initial location and becomes finer while approaching true hypocenter. The target function is a sum of the bell-shaped characteristic functions, used to emphasize true pickings and eliminate outliers. The final solution is a grid point that provides maximum to the target function. The procedure was applied to a list of ML > 4 earthquakes recorded by the Israel Seismic Network (ISN) in the 1999-2002 time period. Most of them are badly constrained relative the network. However, the results of location with average normalized error relative bulletin solutions e=dr/R of 5% were obtained, in each of the distance ranges. The first version of the procedure was incorporated in the national Early Warning System in 2001. Recently, we started to send automatic Early Warn ing reports, to the EMSC Real Time Bulletin. Initially reported some teleseismic location discrepancies have been eliminated by introduction of station corrections.

Modeling Exposure to Electromagnetic Fields with Realistic Anatomical Models: The Brooks Finite Difference Time Domain (FDTD)

DTIC Science & Technology

2008-02-01

1996. [15] Gambrill, C.S. DeAngelis M.L., Lu S-T. Error analysis of a thermometric microwave-dosimetry procedure. In: Blank M, editor. Electricity...Transactions on Biomedical Engineering, Vol. BME-31, No. 7, July 1984, 533-536. [18] Lu S-T, DeAngelis ML, Gambrill CS. Ocular microwave thermometric

Analytic Methods for Adjusting Subjective Rating Schemes

DTIC Science & Technology

1976-06-01

individual performance. The approach developed here is a variant of the classical linear regression model. Specifically, it la proposed that...values of y and X. Moreover, this difference la gener- ally independent of sample size, so that LS estimates are different from ML estimates at...baervationa. H^ever, aa T. -. - ,„ aU . th(. Hit (4.10) la aatlafled, and EKV and ML eatlnatea are equlvalent A practical proble, in applying

Temporary prophylactic intravascular balloon occlusion of the common iliac arteries before cesarean hysterectomy for controlling operative blood loss in abnormal placentation.

PubMed

Chou, Min Min; Kung, Hsiao Fan; Hwang, Jen I; Chen, Wei Chi; Tseng, Jenn Jhy

2015-10-01

The purpose of this study was to investigate the efficacy and safety of temporary prophylactic intravascular balloon occlusion of the common iliac arteries (CIA) before planned cesarean hysterectomy for controlling operative blood loss in abnormal placentation. A retrospective study of 13 pregnant women at risk for placenta accreta identified using sequential obstetric ultrasonography and magnetic resonance imaging from January 2007 to December 2009 was performed. Temporary prophylactic intravascular balloon catheterization of the bilateral CIA before cesarean hysterectomy was performed by interventional radiologists. The maximum duration of occlusion time of CIA must not exceed 60 minutes. The primary outcome for this study included estimated blood loss and secondary outcomes included the development of thromboembolism, disseminated intravascular coagulation and surgical complications. Among these 13 patients, the mean age of the patients was 32.8 ± 0.7 years (range 29-37 years). The mean gestational age at cesarean hysterectomy was 32.2 ± 0.9 weeks (range 28-36 weeks), and the mean intraoperative blood loss was 1902.3 ± 578.8 mL (range 500-8000 mL). Operative bleeding was controlled by conservative treatment without additional surgery in two cases. Importantly, two patients (15.8%) had severe complications possibly related to the interventional procedure. One patient was noted to have a popliteal artery thrombosis. A second patient had an external iliac artery thrombosis with 80-90% occlusion. Both patients required antithrombotic treatment without sequelae. With limited experience in this small series, we observed a statistically significant reduction in operative blood loss after the use of temporary prophylactic balloon occlusion of the CIA technique compared with historical controls of similar demographic characteristics previously published (1902.3 ± 578.8 mL, range 500-8000 mL vs. 4445.7 ± 996.48 mL, range 1040-15,000 mL, p = 0.0402). Additionally, two patients had arterial thrombosis. These preliminary findings are based on a small number of patients, and therefore further investigation is needed to determine the effectiveness and safety of this new technique. Copyright © 2015. Published by Elsevier B.V.

Revision Abdominoplasty with Truncal Liposculpting: A 10-Year Experience.

PubMed

Sterodimas, Aris; Boriani, Filippo; Nicaretta, Beatriz; Pereira, Luiz Haroldo

2018-06-13

Abdominoplasty is one of the most popular body-contouring procedures. Despite its popularity, classic abdominoplasty is still associated with a significant rate of complaints from patients such as: fullness of flanks and epigastric areas, lack of a posterior lumbar curve, hanging skin over the incision line, and visible scars over the flanks and beyond underwear or swimming suit coverage. This study reviews the authors' experience in redo abdominoplasty when the patient is not or partially satisfied with the primary procedure. A total of 115 female and 32 male patients underwent revision abdominoplasty with truncal liposculpting between 2007 and 2016. The age distribution of patients ranged from 33 to 73 years, with a mean of 43.1 years. All the patients included in the study had undergone classic abdominoplasty in a different institution. Overall satisfaction with the body appearance after the combined procedure was rated on a scale of 1-5, where 1 is 'poor,' 2 is 'fair,' 3 is 'good,' 4 is 'very good,' and 5 is 'excellent.' The evaluation was made 12 months after the composite body-contouring procedure. Four hundred to 1500 ml of fat were obtained with liposuction (mean 840 ml). The amount of clean, adipose tissue transplanted to the buttocks varied from 95 to 425 (mean 286 ml) and to the lower limbs from 75 to 270 ml (mean 195 ml). The stromal-enriched lipograft technique was used in all the cases to enrich the fat transplantation. There was no hematoma, infection or deep vein thrombosis. Seventy-five percent reported that their appearance after composite body contouring was 'very good' to 'excellent' (30% 'excellent' and 45% 'very good') and 20% responded that their appearance was 'good.' Only 5% of patients thought their appearance was less than good ('fair'). The average follow-up time for this group of patients has been 6.3 years (range 1-10 years). Truncal liposculpting with modified abdominoplasty accomplishes very good aesthetic results in a single surgical procedure with a low rate of complications and high patient satisfaction in cases of revision abdominoplasties. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Autoshaping of chlordiazepoxide drinking in non-deprived rats.

PubMed

Tomie, Arthur; Wong, Lauren E; Pohorecky, Larissa A

2005-02-28

Effects of autoshaping procedures (Paired versus Random) and sipper fluid [chlordiazepoxide (CDP) versus water] on sipper-directed drinking were evaluated in 32 male Long-Evans rats maintained with free access to food and water. For the Paired/CDP group (n = 16), autoshaping procedures consisted of the presentation of the CDP sipper conditioned stimulus (CS) followed by the response-independent presentation of the food unconditioned stimulus (US). The concentration of CDP in the sipper CS (0.05, 0.10, 0.15, 0.20, and 0.25 mg/ml CDP) was increased across sessions. The Paired/Water group (n = 8) received only water in the sipper CS. The Random/CDP group (n = 8) received the CDP sipper CS and food US randomly with respect to one another. The Paired/CDP group drank significantly more of the 0.20 mg/ml and 0.25 mg/ml CDP solutions than the Random/CDP control, and more fluid than the Paired/Water control group when the sipper CS for the Paired/CDP group contained the three highest concentrations of CDP. CS-Only extinction procedures reliably reduced sipper CS-directed drinking in the Paired/CDP and the Paired/Water groups, but not in the Random/CDP group. Data are consistent with the hypothesis that Pavlovian autoshaping procedures induce sipper CS-directed drinking of CDP in rats deprived of neither food nor fluid. Implications for the autoshaping model of drug abuse are discussed.

Improving the Interoperability of Disaster Models: a Case Study of Proposing Fireml for Forest Fire Model

NASA Astrophysics Data System (ADS)

Jiang, W.; Wang, F.; Meng, Q.; Li, Z.; Liu, B.; Zheng, X.

2018-04-01

This paper presents a new standardized data format named Fire Markup Language (FireML), extended by the Geography Markup Language (GML) of OGC, to elaborate upon the fire hazard model. The proposed FireML is able to standardize the input and output documents of a fire model for effectively communicating with different disaster management systems to ensure a good interoperability. To demonstrate the usage of FireML and testify its feasibility, an adopted forest fire spread model being compatible with FireML is described. And a 3DGIS disaster management system is developed to simulate the dynamic procedure of forest fire spread with the defined FireML documents. The proposed approach will enlighten ones who work on other disaster models' standardization work.

Improved procedure for determination of flucytosine in human blood plasma by high-pressure liquid chromatography.

PubMed Central

Schwertschlag, U; Nakata, L M; Gal, J

1984-01-01

Several high-pressure liquid chromatography procedures for the determination of flucytosine in serum or plasma have appeared. Some of these suffer from significant disadvantages, and none was applicable in our routine clinical therapeutic-drug-monitoring laboratory. A new high-pressure liquid chromatography assay for flucytosine was therefore developed. A 100-microliter sample of plasma was treated with an aqueous 5-iodocytosine internal-standard solution, and the mixture was deproteinized with trichloroacetic acid. A portion of the protein-free supernatant was diluted with 0.1 M ammonium phosphate, and an aliquot of the resulting solution was injected into the high-pressure liquid chromatography system. Chromatography was performed on a strong-cation-exchange column with a mobile phase containing aqueous ammonium phosphate, phosphoric acid, methanol, and acetonitrile. Detection was at 254 nm. The assay was shown to be linear in the 10 to 200-micrograms/ml drug-concentration range. Forty other drugs were tested for potential interference with the assay, and none was found. For routine use, a single-point working standard containing 75 micrograms of flucytosine per ml was used, giving intraassay coefficients of variation at 50 and 150 micrograms/ml of 1.8 and 2.3% respectively, whereas the day-to-day coefficient of variation at 50 micrograms/ml was 10.0%. Advantages of the procedure include the small sample size, the use of a convenient and reliable internal standard, speed, and simplicity. The assay is highly suitable for routine clinical drug-analysis laboratories. PMID:6508261

Economic evaluation of lupus nephritis in the Systemic Lupus International Collaborating Clinics inception cohort using a multistate model approach.

PubMed

Barber, Megan R W; Hanly, John G; Su, Li; Urowitz, Murray B; Pierre, Yvan St; Romero-Diaz, Juanita; Gordon, Caroline; Bae, Sang-Cheol; Bernatsky, Sasha; Wallace, Daniel J; Isenberg, David A; Rahman, Anisur; Ginzler, Ellen M; Petri, Michelle; Bruce, Ian N; Fortin, Paul R; Gladman, Dafna D; Sanchez-Guerrero, Jorge; Ramsey-Goldman, Rosalind; Khamashta, Munther A; Aranow, Cynthia; Mackay, Meggan; Alarcón, Graciela S; Manzi, Susan; Nived, Ola; Jönsen, Andreas; Zoma, Asad A; van Vollenhoven, Ronald F; Ramos-Casals, Manuel; Ruiz-Irastorza, Guillermo; Sam Lim, S; Kalunian, Kenneth C; Inanc, Murat; Kamen, Diane L; Peschken, Christine A; Jacobsen, Soren; Askanase, Anca; Theriault, Chris; Farewell, Vernon; Clarke, Ann E

2017-11-28

Little is known about the long-term costs of lupus nephritis (LN). These were compared between patients with and without LN based on multistate modelling. Patients from 32 centres in 11 countries were enrolled in the Systemic Lupus International Collaborating Clinics (SLICC) inception cohort within 15 months of diagnosis and provided annual data on renal function, hospitalizations, medications, dialysis, and selected procedures. LN was diagnosed by renal biopsy or the American College of Rheumatology classification criteria. Renal function was assessed annually using estimated glomerular filtration rate (eGFR) or proteinuria (ePrU). A multistate model was used to predict 10-year cumulative costs by multiplying annual costs associated with each renal state by the expected state duration. 1,545 patients participated, 89.3% female, mean age at diagnosis 35.2 years (SD 13.4), 49.0% Caucasian, and mean follow up 6.3 years (SD 3.3). LN developed in 39.4% by the end of follow up. Ten-year cumulative costs were greater in those with LN and an eGFR < 30 ml/min ($310 579 2015 Canadian dollars versus $19 987 if no LN and eGFR > 60 ml/min) or with LN and ePrU > 3 g/d ($84 040 versus $20 499 if no LN and ePrU < 0.25 g/d). Patients with eGFR < 30 ml/min incurred 10-year costs 15-fold higher than those with normal eGFR. By estimating the expected duration in each renal state and incorporating associated annual costs, disease severity at presentation can be used to anticipate future healthcare costs. This is critical knowledge for cost-effectiveness evaluations of novel therapies. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Effect of positive end-expiratory pressure on blood loss during retropubic and robot-assisted laparoscopic radical prostatectomy.

PubMed

Ehieli, Eric I; Howard, Lauren E; Monk, Terri G; Ferrandino, Michael N; Polascik, Thomas J; Walther, Philip J; Freedland, Stephen J

2016-08-01

To study the effect of end-expiratory pressure used during anesthesia on blood loss during radical prostatectomy. We evaluated 247 patients who underwent either radical retropubic prostatectomy or robot-assisted laparoscopic prostatectomy at a single institution from 2008 to 2013 by one of four surgeons. Patient characteristics were compared using t-tests, rank sum or χ(2) -tests as appropriate. The association between positive end-expiratory pressure and estimated blood loss was tested using linear regression. Patients were classified into high (≥4 cmH2 O) and low (≤1 cmH2 O) positive-end expiratory pressure groups. Estimated blood loss in radical retropubic prostatectomy was higher in the high positive end-expiratory pressure group (1000 mL vs 800 mL, P = 0.042). Estimated blood loss in robot-assisted laparoscopic prostatectomy was lower in the high positive end-expiratory pressure group (150 mL vs 250 mL, P = 0.015). After adjusting for other factors known to influence blood loss, a 5-cmH2 O increase in positive end-expiratory pressure was associated with a 34.9% increase in estimated blood loss (P = 0.030) for radical retropubic prostatectomy, and a 33.0% decrease for robot-assisted laparoscopic prostatectomy (P = 0.038). In radical retropubic prostatectomy, high positive end-expiratory pressure was associated with higher estimated blood loss, and the benefits of positive end-expiratory pressure should be weighed against the risk of increased estimated blood loss. In robot-assisted laparoscopic prostatectomy, high positive end-expiratory pressure was associated with lower estimated blood loss, and might have more than just pulmonary benefits. © 2016 The Japanese Urological Association.

The use of phosphatidylcholine for correction of localized fat deposits.

PubMed

Rittes, Patrícia Guedes

2003-01-01

Subjects with localized fat deposits commonly receive suction lipectomy as a cosmetic procedure. A new office procedure for correction of those superficial fat deposits was applied in 50 patients by injection of phosphatidylcholine. The method itself consists of using a 3OG1/2 insulin needle to inject about 5 ml (250 mg/5 ml) of phosphatidylcholine into the fat, distributing it evenly in an 80 cm2 area. Pre- and posttreatment photographs were taken for technical planning and analysis of the results over the long term. A clear improvement occurred in all, with a marked reduction of the fat deposits without recurrence over a 2-year follow-up period and no weight gain. The injection of phosphatidylcholine into the fat deposits is a simple office procedure that can sometimes postpone or even replace surgery and liposuction.

Automatic Texture Mapping of Architectural and Archaeological 3d Models

NASA Astrophysics Data System (ADS)

Kersten, T. P.; Stallmann, D.

2012-07-01

Today, detailed, complete and exact 3D models with photo-realistic textures are increasingly demanded for numerous applications in architecture and archaeology. Manual texture mapping of 3D models by digital photographs with software packages, such as Maxon Cinema 4D, Autodesk 3Ds Max or Maya, still requires a complex and time-consuming workflow. So, procedures for automatic texture mapping of 3D models are in demand. In this paper two automatic procedures are presented. The first procedure generates 3D surface models with textures by web services, while the second procedure textures already existing 3D models with the software tmapper. The program tmapper is based on the Multi Layer 3D image (ML3DImage) algorithm and developed in the programming language C++. The studies showing that the visibility analysis using the ML3DImage algorithm is not sufficient to obtain acceptable results of automatic texture mapping. To overcome the visibility problem the Point Cloud Painter algorithm in combination with the Z-buffer-procedure will be applied in the future.

Chemical Modification of the Olfactory Receptor Epithelium of Vertebrate Species

DTIC Science & Technology

1990-06-28

Pre-column Derivatization Procedure: 1.0 mL of the Jeffamine solution was mixed with 1.0 mL of NaCN, 5.0 mL of phosphate buffer pH 9.5 followed by 1.0...running buffer. All the unprotonated components elute at the same time because their rate of elution is controlled only by the rate of electroosmotic ...elecarosomotic mobility under our experimental conditions. Using an average elution time of 22.2 min the measured electroosmotic mobility is 1.3 x 10-4 cm2

Applying Modeling Tools to Ground System Procedures

NASA Technical Reports Server (NTRS)

Di Pasquale, Peter

2012-01-01

As part of a long-term effort to revitalize the Ground Systems (GS) Engineering Section practices, Systems Modeling Language (SysML) and Business Process Model and Notation (BPMN) have been used to model existing GS products and the procedures GS engineers use to produce them.

Correlation of ultrasound estimated placental volume and umbilical cord blood volume in term pregnancy.

PubMed

Pannopnut, Papinwit; Kitporntheranunt, Maethaphan; Paritakul, Panwara; Kongsomboon, Kittipong

2015-01-01

To investigate the correlation between ultrasound measured placental volume and collected umbilical cord blood (UCB) volume in term pregnancy. An observational cross-sectional study of term singleton pregnant women in the labor ward at Maha Chakri Sirindhorn Medical Center was conducted. Placental thickness, height, and width were measured using two-dimensional (2D) ultrasound and calculated for placental volume using the volumetric mathematic model. After the delivery of the baby, UCB was collected and measured for its volume immediately. Then, birth weight, placental weight, and the actual placental volume were analyzed. The Pearson's correlation was used to determine the correlation between each two variables. A total of 35 pregnant women were eligible for the study. The mean and standard deviation of estimated placental volume and actual placental volume were 534±180 mL and 575±118 mL, respectively. The median UCB volume was 140 mL (range 98-220 mL). The UCB volume did not have a statistically significant correlation with the estimated placental volume (correlation coefficient 0.15; p=0.37). However, the UCB volume was significantly correlated with the actual placental volume (correlation coefficient 0.62; p<0.001) and birth weight (correlation coefficient 0.38; p=0.02). The estimated placental volume by 2D ultrasound was not significantly correlated with the UCB volume. Further studies to establish the correlation between the UCB volume and the estimated placental volume using other types of placental imaging may be needed.

Leak Detection and Location of Water Pipes Using Vibration Sensors and Modified ML Prefilter.

PubMed

Choi, Jihoon; Shin, Joonho; Song, Choonggeun; Han, Suyong; Park, Doo Il

2017-09-13

This paper proposes a new leak detection and location method based on vibration sensors and generalised cross-correlation techniques. Considering the estimation errors of the power spectral densities (PSDs) and the cross-spectral density (CSD), the proposed method employs a modified maximum-likelihood (ML) prefilter with a regularisation factor. We derive a theoretical variance of the time difference estimation error through summation in the discrete-frequency domain, and find the optimal regularisation factor that minimises the theoretical variance in practical water pipe channels. The proposed method is compared with conventional correlation-based techniques via numerical simulations using a water pipe channel model, and it is shown through field measurement that the proposed modified ML prefilter outperforms conventional prefilters for the generalised cross-correlation. In addition, we provide a formula to calculate the leak location using the time difference estimate when different types of pipes are connected.

Leak Detection and Location of Water Pipes Using Vibration Sensors and Modified ML Prefilter

PubMed Central

Shin, Joonho; Song, Choonggeun; Han, Suyong; Park, Doo Il

2017-01-01

This paper proposes a new leak detection and location method based on vibration sensors and generalised cross-correlation techniques. Considering the estimation errors of the power spectral densities (PSDs) and the cross-spectral density (CSD), the proposed method employs a modified maximum-likelihood (ML) prefilter with a regularisation factor. We derive a theoretical variance of the time difference estimation error through summation in the discrete-frequency domain, and find the optimal regularisation factor that minimises the theoretical variance in practical water pipe channels. The proposed method is compared with conventional correlation-based techniques via numerical simulations using a water pipe channel model, and it is shown through field measurement that the proposed modified ML prefilter outperforms conventional prefilters for the generalised cross-correlation. In addition, we provide a formula to calculate the leak location using the time difference estimate when different types of pipes are connected. PMID:28902154

Maximum Likelihood Reconstruction for Magnetic Resonance Fingerprinting

PubMed Central

Zhao, Bo; Setsompop, Kawin; Ye, Huihui; Cauley, Stephen; Wald, Lawrence L.

2017-01-01

This paper introduces a statistical estimation framework for magnetic resonance (MR) fingerprinting, a recently proposed quantitative imaging paradigm. Within this framework, we present a maximum likelihood (ML) formalism to estimate multiple parameter maps directly from highly undersampled, noisy k-space data. A novel algorithm, based on variable splitting, the alternating direction method of multipliers, and the variable projection method, is developed to solve the resulting optimization problem. Representative results from both simulations and in vivo experiments demonstrate that the proposed approach yields significantly improved accuracy in parameter estimation, compared to the conventional MR fingerprinting reconstruction. Moreover, the proposed framework provides new theoretical insights into the conventional approach. We show analytically that the conventional approach is an approximation to the ML reconstruction; more precisely, it is exactly equivalent to the first iteration of the proposed algorithm for the ML reconstruction, provided that a gridding reconstruction is used as an initialization. PMID:26915119

Maximum Likelihood Reconstruction for Magnetic Resonance Fingerprinting.

PubMed

Zhao, Bo; Setsompop, Kawin; Ye, Huihui; Cauley, Stephen F; Wald, Lawrence L

2016-08-01

This paper introduces a statistical estimation framework for magnetic resonance (MR) fingerprinting, a recently proposed quantitative imaging paradigm. Within this framework, we present a maximum likelihood (ML) formalism to estimate multiple MR tissue parameter maps directly from highly undersampled, noisy k-space data. A novel algorithm, based on variable splitting, the alternating direction method of multipliers, and the variable projection method, is developed to solve the resulting optimization problem. Representative results from both simulations and in vivo experiments demonstrate that the proposed approach yields significantly improved accuracy in parameter estimation, compared to the conventional MR fingerprinting reconstruction. Moreover, the proposed framework provides new theoretical insights into the conventional approach. We show analytically that the conventional approach is an approximation to the ML reconstruction; more precisely, it is exactly equivalent to the first iteration of the proposed algorithm for the ML reconstruction, provided that a gridding reconstruction is used as an initialization.

9 CFR 147.13 - Procedure for bacteriological culturing of eggshells for colon bacilli organisms.

Code of Federal Regulations, 2010 CFR

2010-01-01

... the eggs will be rubbed with a sterile swab previously moistened with sterile lactose broth, or other... tube containing four swabs and lactose broth or other suitable media, 1 ml. will be transferred to 10 ml. lactose in a fermentation tube. (2) Incubate at 37 °C for 48 hours. The presence of acid, and gas...

9 CFR 147.13 - Procedure for bacteriological culturing of eggshells for colon bacilli organisms.

Code of Federal Regulations, 2011 CFR

2011-01-01

... the eggs will be rubbed with a sterile swab previously moistened with sterile lactose broth, or other... tube containing four swabs and lactose broth or other suitable media, 1 ml. will be transferred to 10 ml. lactose in a fermentation tube. (2) Incubate at 37 °C for 48 hours. The presence of acid, and gas...

Proteinuria and Reduced Estimated Glomerular Filtration Rate Independently Predict Risk for Acute Myocardial Infarction: Findings from a Population-Based Study in Keelung, Taiwan.

PubMed

Chang, Shu-Hsuan; Tsai, Chia-Ti; Yen, Amy Ming-Fang; Lei, Meng-Huan; Chen, Hsiu-Hsi; Tseng, Chuen-Den

2015-03-01

The aim of this study was to evaluate the independent roles of proteinuria and reduced estimated glomerular filtration rate (GFR) in the development of acute myocardial infarction in a northern Taiwanese population. We conducted a community-based prospective cohort study in Keelung, the northernmost county of Taiwan. A total of 63,129 subjects (63% women) ≥ 20 years of age who had no history of coronary heart disease were recruited and followed-up. Univariate and multivariate proportional hazards regression analysis was performed to assess the association between proteinuria and estimated GFR and the risk of acute myocardial infarction. There were 305 new cases of acute myocardial infarction (114 women and 191 men) documented during a four-year follow-up period. After adjustment of potential confounding covariates, heavier proteinuria (dipstick urinalysis reading 3+) and estimated GFR of less than 60 ml/min/1.73 m(2) independently predicted increased risk of developing acute myocardial infarction. The adjusted hazard ratio (aHR) of heavier proteinuria for occurrence of acute myocardial infarction was 1.85 [95% confidence intervals (CI), 1.17-2.91, p < 0.01] (vs. the reference group: negative dipstick proteinuria). The aHR of estimated GFR of 30-59 ml/min/1.73 m(2) for occurrence of acute myocardial infarction was 2.4 (95% CI, 1.31-4.38, p < 0.01) (vs. the reference group: estimated GFR ≥ 90 ml/ min/1.73 m(2)), and that of estimated GFR of 15-29 ml/min/1.73 m(2) was 5.26 (95% CI, 2.26-12.26, p < 0.01). We demonstrated that both heavier proteinuria and lower estimated GFR are significant independent predictors of developing future acute myocardial infarction in a northern Taiwanese population. Acute myocardial infarction; Estimated glomerular filtration rate; Proteinuria.

A methodology for airplane parameter estimation and confidence interval determination in nonlinear estimation problems. Ph.D. Thesis - George Washington Univ., Apr. 1985

NASA Technical Reports Server (NTRS)

Murphy, P. C.

1986-01-01

An algorithm for maximum likelihood (ML) estimation is developed with an efficient method for approximating the sensitivities. The ML algorithm relies on a new optimization method referred to as a modified Newton-Raphson with estimated sensitivities (MNRES). MNRES determines sensitivities by using slope information from local surface approximations of each output variable in parameter space. With the fitted surface, sensitivity information can be updated at each iteration with less computational effort than that required by either a finite-difference method or integration of the analytically determined sensitivity equations. MNRES eliminates the need to derive sensitivity equations for each new model, and thus provides flexibility to use model equations in any convenient format. A random search technique for determining the confidence limits of ML parameter estimates is applied to nonlinear estimation problems for airplanes. The confidence intervals obtained by the search are compared with Cramer-Rao (CR) bounds at the same confidence level. The degree of nonlinearity in the estimation problem is an important factor in the relationship between CR bounds and the error bounds determined by the search technique. Beale's measure of nonlinearity is developed in this study for airplane identification problems; it is used to empirically correct confidence levels and to predict the degree of agreement between CR bounds and search estimates.

Estimates and Standard Errors for Ratios of Normalizing Constants from Multiple Markov Chains via Regeneration

PubMed Central

Doss, Hani; Tan, Aixin

2017-01-01

In the classical biased sampling problem, we have k densities π1(·), …, πk(·), each known up to a normalizing constant, i.e. for l = 1, …, k, πl(·) = νl(·)/ml, where νl(·) is a known function and ml is an unknown constant. For each l, we have an iid sample from πl,·and the problem is to estimate the ratios ml/ms for all l and all s. This problem arises frequently in several situations in both frequentist and Bayesian inference. An estimate of the ratios was developed and studied by Vardi and his co-workers over two decades ago, and there has been much subsequent work on this problem from many different perspectives. In spite of this, there are no rigorous results in the literature on how to estimate the standard error of the estimate. We present a class of estimates of the ratios of normalizing constants that are appropriate for the case where the samples from the πl’s are not necessarily iid sequences, but are Markov chains. We also develop an approach based on regenerative simulation for obtaining standard errors for the estimates of ratios of normalizing constants. These standard error estimates are valid for both the iid case and the Markov chain case. PMID:28706463

Functional improvement in patients with idiopathic pulmonary fibrosis undergoing single lung transplantation *

PubMed Central

Rubin, Adalberto Sperb; Nascimento, Douglas Zaione; Sanchez, Letícia; Watte, Guilherme; Holand, Arthur Rodrigo Ronconi; Fassbind, Derrick Alexandre; Camargo, José Jesus

2015-01-01

Abstract Objective: To evaluate the changes in lung function in the first year after single lung transplantation in patients with idiopathic pulmonary fibrosis (IPF). Methods: We retrospectively evaluated patients with IPF who underwent single lung transplantation between January of 2006 and December of 2012, reviewing the changes in the lung function occurring during the first year after the procedure. Results: Of the 218 patients undergoing lung transplantation during the study period, 79 (36.2%) had IPF. Of those 79 patients, 24 (30%) died, and 11 (14%) did not undergo spirometry at the end of the first year. Of the 44 patients included in the study, 29 (66%) were men. The mean age of the patients was 57 years. Before transplantation, mean FVC, FEV1, and FEV1/FVC ratio were 1.78 L (50% of predicted), 1.48 L (52% of predicted), and 83%, respectively. In the first month after transplantation, there was a mean increase of 12% in FVC (400 mL) and FEV1 (350 mL). In the third month after transplantation, there were additional increases, of 5% (170 mL) in FVC and 1% (50 mL) in FEV1. At the end of the first year, the functional improvement persisted, with a mean gain of 19% (620 mL) in FVC and 16% (430 mL) in FEV1. Conclusions: Single lung transplantation in IPF patients who survive for at least one year provides significant and progressive benefits in lung function during the first year. This procedure is an important therapeutic alternative in the management of IPF. PMID:26398749

Bardoxolone methyl and kidney function in CKD with type 2 diabetes.

PubMed

Pergola, Pablo E; Raskin, Philip; Toto, Robert D; Meyer, Colin J; Huff, J Warren; Grossman, Eric B; Krauth, Melissa; Ruiz, Stacey; Audhya, Paul; Christ-Schmidt, Heidi; Wittes, Janet; Warnock, David G

2011-07-28

Chronic kidney disease (CKD) associated with type 2 diabetes is the leading cause of kidney failure, with both inflammation and oxidative stress contributing to disease progression. Bardoxolone methyl, an oral antioxidant inflammation modulator, has shown efficacy in patients with CKD and type 2 diabetes in short-term studies, but longer-term effects and dose response have not been determined. In this phase 2, double-blind, randomized, placebo-controlled trial, we assigned 227 adults with CKD (defined as an estimated glomerular filtration rate [GFR] of 20 to 45 ml per minute per 1.73 m(2) of body-surface area) in a 1:1:1:1 ratio to receive placebo or bardoxolone methyl at a target dose of 25, 75, or 150 mg once daily. The primary outcome was the change from baseline in the estimated GFR with bardoxolone methyl, as compared with placebo, at 24 weeks; a secondary outcome was the change at 52 weeks. Patients receiving bardoxolone methyl had significant increases in the mean (±SD) estimated GFR, as compared with placebo, at 24 weeks (with between-group differences per minute per 1.73 m(2) of 8.2±1.5 ml in the 25-mg group, 11.4±1.5 ml in the 75-mg group, and 10.4±1.5 ml in the 150-mg group; P<0.001). The increases were maintained through week 52, with significant differences per minute per 1.73 m(2) of 5.8±1.8 ml, 10.5±1.8 ml, and 9.3±1.9 ml, respectively. Muscle spasms, the most frequent adverse event in the bardoxolone methyl groups, were generally mild and dose-related. Hypomagnesemia, mild increases in alanine aminotransferase levels, and gastrointestinal effects were more common among patients receiving bardoxolone methyl. Bardoxolone methyl was associated with improvement in the estimated GFR in patients with advanced CKD and type 2 diabetes at 24 weeks. The improvement persisted at 52 weeks, suggesting that bardoxolone methyl may have promise for the treatment of CKD. (Funded by Reata Pharmaceuticals; BEAM ClinicalTrials.gov number, NCT00811889.).

Use of a mobile tower-based robot--The initial Xi robot experience in surgical oncology.

PubMed

Yuh, Bertram; Yu, Xian; Raytis, John; Lew, Michael; Fong, Yuman; Lau, Clayton

2016-01-01

The da Vinci Xi platform provides expanded movement of the arms relative to the base, theoretically allowing increased versatility in complex multi-field or multi-quadrant surgery. We describe the initial Xi experience in oncologic surgery at a tertiary cancer center. One hundred thirty unique robot-assisted procedures were performed using the Xi between 2014 and 2015, 112 of which were oncology surgeries. For procedures involving multiple quadrants, the robot was re-targeted. Complications were assessed according to Martin criteria and the Clavien-Dindo classification up to 90 days after operation. Thirteen different operations were performed in five oncology subspecialties (urology, gynecology, thoracic, hepatobiliary, and gastrointestinal surgery). Median operative times ranged from 183 min for nephroureterectomy to 543 min for esophagogastrectomy. Median estimated blood loss did not exceed 200 ml for any of the categorized procedures . No patients were transfused intraoperatively and no positioning injuries occurred. Conversions to open operation occurred in three cases (2.7%), though not related to complications or technical considerations. Overall complication rate was 26% with major complication rate of 4%. Readmissions were necessary in 11 (10%) patients. The da Vinci Xi can be safely assimilated into a surgical oncology program. The Xi offers versatility to various oncologic procedures with satisfactory complication and readmission rates. © 2015 Wiley Periodicals, Inc.

Preconcentration and determination of boron in milk, infant formula, and honey samples by solid phase extraction-electrothermal atomic absorption spectrometry

NASA Astrophysics Data System (ADS)

López-García, I.; Viñas, P.; Romero-Romero, R.; Hernández-Córdoba, M.

2009-02-01

This work presents alternative procedures for the electrothermal atomic absorption spectrometric determination of boron in milk, infant formulas, and honey samples. Honey samples (10% m/v) were diluted in a medium containing 1% v/v HNO 3 and 50% v/v H 2O 2 and introduced in the atomizer. A mixture of 20 µg Pd and 0.5 µg Mg was used for chemical modification. Calibration was carried out using aqueous solutions prepared in the same medium, in the presence of 10% m/v sucrose. The detection limit was 2 µg g - 1 , equivalent to three times the standard error of the estimate ( sy/ x) of the regression line. For both infant formulas and milk samples, due to their very low boron content, we used a procedure based on preconcentration by solid phase extraction (Amberlite IRA 743), followed by elution with 2 mol L - 1 hydrochloric acid. Detection limits were 0.03 µg g - 1 for 4% m/v honey, 0.04 µg g - 1 for 5% m/v infant formula and 0.08 µg mL - 1 for 15% v/v cow milk. We confirmed the accuracy of the procedure by comparing the obtained results with those found via a comparable independent procedure, as well by the analysis of four certified reference materials.

Some blood chemistry values for the Rainbow Trout (Salmo gairdneri)

USGS Publications Warehouse

Wedemeyer, Gary; Chatterton, K.

1970-01-01

Normal distribution curves were graphically fitted to approximately 1400 clinical test values obtained from the plasma or kidney tissue of more than 200 yearling rainbow trout (Salmo gairdneri). Estimated normal ranges were ascorbate, 102–214 μg/g; blood urea nitrogen (BUN), 0.9–4.5 mg/100 ml; chloride, 84–132 mEq/liter; cholesterol, 161–365 mg/100 ml; cortisol, 1.5–18.5 μg/100 ml; glucose, 41–151 mg/100 ml; and total protein, 2–6 g/100 ml.

40 CFR 1065.720 - Liquefied petroleum gas.

Code of Federal Regulations, 2011 CFR

2011-07-01

... CONTROLS ENGINE-TESTING PROCEDURES Engine Fluids, Test Fuels, Analytical Gases and Other Calibration....720—Test Fuel Specifications for Liquefied Petroleum Gas Item Value Reference procedure 1 Propane... test fuel must not yield a persistent oil ring when you add 0.3 ml of solvent residue mixture to a...

40 CFR 1065.720 - Liquefied petroleum gas.

Code of Federal Regulations, 2013 CFR

2013-07-01

... CONTROLS ENGINE-TESTING PROCEDURES Engine Fluids, Test Fuels, Analytical Gases and Other Calibration....720—Test Fuel Specifications for Liquefied Petroleum Gas Item Value Reference procedure 1 Propane... test fuel must not yield a persistent oil ring when you add 0.3 ml of solvent residue mixture to a...

40 CFR 1065.720 - Liquefied petroleum gas.

Code of Federal Regulations, 2012 CFR

2012-07-01

... CONTROLS ENGINE-TESTING PROCEDURES Engine Fluids, Test Fuels, Analytical Gases and Other Calibration....720—Test Fuel Specifications for Liquefied Petroleum Gas Item Value Reference procedure 1 Propane... test fuel must not yield a persistent oil ring when you add 0.3 ml of solvent residue mixture to a...

Microchemical urinalysis. IX - Determination of hydroxyproline in urine.

NASA Technical Reports Server (NTRS)

Grunbaum, B. W.; Pace, N.

1973-01-01

A simplified procedure is described for the determination of hydroxyproline in human or monkey urine. In this procedure 1 ml of urine is subjected in succession to hydrolysis, oxidation, extraction, and color development. During these steps impurities and interfering substances are eliminated, thus resulting in a chromophore due to hydroxyproline alone.

Human Blood Typing: A Forensic Science Approach: Part II. Experiments.

ERIC Educational Resources Information Center

Kobilinsky, Lawrence; Sheehan, Francis X.

1988-01-01

Describes several experiments that explore the methodology available to the forensic serologist for typing a human bloodstain in the ABH grouping system. Presents ABO blood group of wet blood, Lattes Crust test procedure, and the absorption-elution procedure. Uses outdated blood; equipment requirements are minimal. (ML)

Lectin Enzyme Assay Detection of Viruses, Tissue Culture, and a Mycotoxin Simulant

DTIC Science & Technology

1988-09-01

micromix vibrator at 37 OC for 10-30 min. 9. Read color development at 10, 20, and 30 min. Table 5. LEAD Test (Procedure II). 1. Add 0.1 mL of virus...or TC concentrations to 0.1 mL of WGA- peroxidase in microtiter tray. 2. Mix on yankee rotator or micromix vibrator at room temperature for 10 min. 3

Acute and delayed toxicity of gemcitabine administered during isolated lung perfusion: a preclinical dose-escalation study in pigs.

PubMed

Pagès, Pierre-Benoit; Derangere, Valentin; Bouchot, Olivier; Magnin, Guy; Charon-Barra, Céline; Lokiec, François; Ghiringhelli, François; Bernard, Alain

2015-08-01

Colorectal cancer is the third most commonly diagnosed cancer worldwide, with up to 25% of patients presenting with metastases at the time of diagnosis. Despite pulmonary metastasectomy many patients go on to develop pulmonary recurrence, which might be linked to the presence of lung micrometastases. In this setting, the adjuvant administration of high-dose chemotherapy by isolated lung perfusion (ILP) has shown encouraging results. However, the tolerance to and efficacy of modern gemcitabine (GEM)-based chemotherapy regimens during adjuvant ILP remain unknown. We conducted a dose-escalating preclinical study to evaluate the immediate and delayed toxicity of GEM in a pig model to define dose-limiting toxicity (DLT) and maximum tolerated concentration. Twenty-three pigs were given increasing concentrations of GEM during ILP, and were awakened at the end of the procedure. The concentrations of GEM were 40, 80, 160, 320, 640 and 1280 µg/ml. Serum and lung samples were taken to measure GEM concentrations. Pulmonary damage was evaluated by histological examination and cleaved caspase-3 detection. Immediate and delayed (1 month) toxicity were recorded. All of the animals underwent successful ILP with GEM. No systemic leak was observed. The three pigs that received a concentration of GEM of 1280 µg/ml died of hypoxia after lung recirculation at the end of the procedure. Eleven pigs survived for 1 month. Major lung toxicity was observed for the concentration of GEM of 640 µg/ml, both at the end of the procedure and after 1 month. DLT was defined at the concentration of 640 µg/ml and the maximum tolerated dose (MTD) was defined at the concentration of 320 µg/ml. ILP with GEM is a safe and reproducible technique in this large-animal model, which includes 1 month of survival. The MTD in this pig model was a concentration of GEM of 320 µg/ml. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

The effect of prilocaine and prilocaine plus meperidine infiltration on the pain during nasal packing removal.

PubMed

Karaaslan, Kazim; Yilmaz, Fahrettin; Gulcu, Nebahat; Yigit, Beyhan; Kocoglu, Hasan

2007-12-01

Removing the nasal packing after nasal surgery is an uncomfortable and painful procedure. Since there is no controlled trial described in the literature about the local use of meperidine during packing removal, we aimed to compare the analgesic and sedative effects of the meperidine-prilocaine combination, injected into the packing 15 minutes before the procedure, with that of prilocaine during packing removal. Fifty adult patients, for whom nasal packing removal after nasal septoplasty was scheduled, were randomly allocated into one of two groups. In the prilocaine group (Group P, n = 25), 5 ml of 1% prilocaine in saline was injected into the pack 15 minutes before removal. In the prilocaine-meperidine group (Group MP, n = 25), 5 ml fluid combination containing prilocaine (10 mg/ml) and meperidine (1 mg/kg) was injected in nasal packs. Five ml saline was injected into the package in the contra-lateral nostril in both groups as control. Visual analogue scale (VAS) score was recorded during injections (t) and packing removal (t), and the Ramsay sedation score was evaluated. VAS score was not different from the control nostril in Group P (p > 0.05), where as it was significantly lower than the control nostril in Group MP (p < 0.05). Ramsay sedation scores were significantly higher in Group MP compared to the control nostril and actively treated nostril of Group P (p < 0.05). The injection of prilocaine plus meperidine into the nasal pack 15 minutes before nasal packing removal provides effective analgesia and mild sedation during the procedure.

Novel approaches to analysis by flow injection gradient titration.

PubMed

Wójtowicz, Marzena; Kozak, Joanna; Kościelniak, Paweł

2007-09-26

Two novel procedures for flow injection gradient titration with the use of a single stock standard solution are proposed. In the multi-point single-line (MP-SL) method the calibration graph is constructed on the basis of a set of standard solutions, which are generated in a standard reservoir and subsequently injected into the titrant. According to the single-point multi-line (SP-ML) procedure the standard solution and a sample are injected into the titrant stream from four loops of different capacities, hence four calibration graphs are able to be constructed and the analytical result is calculated on the basis of a generalized slope of these graphs. Both approaches have been tested on the example of spectrophotometric acid-base titration of hydrochloric and acetic acids with using bromothymol blue and phenolphthalein as indicators, respectively, and sodium hydroxide as a titrant. Under optimized experimental conditions the analytical results of precision less than 1.8 and 2.5% (RSD) and of accuracy less than 3.0 and 5.4% (relative error (RE)) were obtained for MP-SL and SP-ML procedures, respectively, in ranges of 0.0031-0.0631 mol L(-1) for samples of hydrochloric acid and of 0.1680-1.7600 mol L(-1) for samples of acetic acid. The feasibility of both methods was illustrated by applying them to the total acidity determination in vinegar samples with precision lower than 0.5 and 2.9% (RSD) for MP-SL and SP-ML procedures, respectively.

Improving precision of glomerular filtration rate estimating model by ensemble learning.

PubMed

Liu, Xun; Li, Ningshan; Lv, Linsheng; Fu, Yongmei; Cheng, Cailian; Wang, Caixia; Ye, Yuqiu; Li, Shaomin; Lou, Tanqi

2017-11-09

Accurate assessment of kidney function is clinically important, but estimates of glomerular filtration rate (GFR) by regression are imprecise. We hypothesized that ensemble learning could improve precision. A total of 1419 participants were enrolled, with 1002 in the development dataset and 417 in the external validation dataset. GFR was independently estimated from age, sex and serum creatinine using an artificial neural network (ANN), support vector machine (SVM), regression, and ensemble learning. GFR was measured by 99mTc-DTPA renal dynamic imaging calibrated with dual plasma sample 99mTc-DTPA GFR. Mean measured GFRs were 70.0 ml/min/1.73 m 2 in the developmental and 53.4 ml/min/1.73 m 2 in the external validation cohorts. In the external validation cohort, precision was better in the ensemble model of the ANN, SVM and regression equation (IQR = 13.5 ml/min/1.73 m 2 ) than in the new regression model (IQR = 14.0 ml/min/1.73 m 2 , P < 0.001). The precision of ensemble learning was the best of the three models, but the models had similar bias and accuracy. The median difference ranged from 2.3 to 3.7 ml/min/1.73 m 2 , 30% accuracy ranged from 73.1 to 76.0%, and P was > 0.05 for all comparisons of the new regression equation and the other new models. An ensemble learning model including three variables, the average ANN, SVM, and regression equation values, was more precise than the new regression model. A more complex ensemble learning strategy may further improve GFR estimates.

Fully Transradial Versus Transfemoral Approach for Percutaneous Intervention of Coronary Chronic Total Occlusions Applying the Hybrid Algorithm: Insights From RECHARGE Registry.

PubMed

Bakker, Erik Jan; Maeremans, Joren; Zivelonghi, Carlo; Faurie, Benjamin; Avran, Alexandre; Walsh, Simon; Spratt, James C; Knaapen, Paul; Hanratty, Colm G; Bressollette, Erwan; Kayaert, Peter; Bagnall, Alan J; Egred, Mohaned; Smith, David; McEntegart, Margaret B; Smith, William H T; Kelly, Paul; Irving, John; Smith, Elliot J; Strange, Julian W; Dens, Joseph; Agostoni, Pierfrancesco

2017-09-01

Small observational studies demonstrate the feasibility of transradial approach for chronic total occlusion (CTO) percutaneous coronary intervention. The aim of the current study is to assess technical success, complication rates, and procedural efficiency in fully transradial approach (fTRA) and transfemoral approach (TFA) in a large prospective European registry adopting the hybrid algorithm for CTO percutaneous coronary intervention (Registry of CrossBoss and Hybrid Procedures in France, the Netherlands, Belgium and United Kingdom, RECHARGE registry). We analyzed 1253 CTO percutaneous coronary intervention procedures performed according to the hybrid protocol in 17 European centers, comparing fTRA (single or biradial access) and TFA (single or bifemoral or combined radial and femoral access). fTRA was applied in 306 (24%) and TFA in 947 (76%) cases. The average Japanese CTO score was 2.1±1.2 in fTRA and 2.3±1.1 in TFA ( P =0.06). Technical success was achieved in 85% in fTRA and 86% in TFA ( P =0.51). Technical success was comparable for fTRA and TFA in different Japanese CTO score subgroups after multivariable analysis and after propensity adjustment. In-hospital major adverse cardiac and cerebral events occurred in 2.0% in fTRA and 2.9% in TFA ( P =0.40). Major access site bleeding occurred in 0.3% in fTRA and 0.5% in TFA ( P =0.66). fTRA compared with TFA had similar procedural duration (80 minutes [54-120 minutes] versus 90 minutes [60-121 minutes]; P =0.07), similar radiation dose (dose area product 89 Gray×cm 2 [52-163 Gray×cm 2 ] versus 101 Gray×cm 2 [59-171 Gray×cm 2 ]; P =0.06), and lower contrast agent use (200 mL [150-310 mL] versus 250 mL [200-350 mL]; P <0.01). fTRA CTO percutaneous coronary intervention is a valid alternative to TFA with a high rate of success, low complication rates, and no decrease in procedural efficiency. © 2017 American Heart Association, Inc.

Magnetic navigation system and CT roadmap-assisted percutaneous coronary intervention: a comparison to the conventional approach.

PubMed

Hao, Ruina; Zhang, Qiu; Xu, Zhuowen; Tang, Lijun; Yang, Zhijian; Cao, Kejiang; Li, Chunjian

2013-04-01

Computed tomography coronary angiography (CTCA) has been successfully integrated with the magnetic navigation system (MNS) to facilitate a roadmap-assisted percutaneous coronary intervention (PCI). The aim of this study was to compare this new approach of PCI versus conventional PCI regarding the difference of contrast usage, x-ray exposure, procedure success, and in-hospital expenses. Thirty-eight patients with stable coronary artery disease and coronary artery lesions of ≥70% diameter stenosis diagnosed by both pre-procedure CTCA and coronary angiography (CAG) were enrolled to receive the MNS and CT roadmap-assisted PCI. Another 38 patients were consecutively recruited to receive conventional PCI, matched with the MNS group by the vessel and lesion type base on American College of Cardiology/American Heart Association criteria. Regarding the process of the guidewire placement, wherein the technical difference of the two procedures exists, the median contrast usage for guidewire crossing was significantly lower in the MNS group than in the conventional group [0.0 mL (interquartile range [IQR], 0.0-3.0 mL) vs 5.0 mL (IQR, 3.1-6.8 mL); P<.001], with zero contrast usage in 25 of the 44 guidewire placements in the MNS group, but in none of the conventional group; the radiation dosage for guidewire crossing in the MNS group was also significantly lower than in the conventional group (235.8 μGym² [IQR, 134.9-455.1 μGym²] vs 364.4 μGym² [IQR, 223.4-547.2 μGym²]; P=.033). There were no significant differences between the two groups concerning the total contrast usage, total radiation dosage of the PCI, the procedural fees, or the overall in-hospital expenses. All of the enrolled vessels were successfully intervened in both groups. In PCI of simple lesions, the application of CT guidance and magnetic navigation had modest impacts on radiation dosage and contrast usage for wire crossing, but no impact on overall radiation dosage or contrast usage for the procedure. In addition, the use of CT roadmap and MNS was likely more expensive compared to PCI using conventional radiographic technique.

Preconcentration of Zn2+ and Cu2+ ions from food and vegetable samples using modified activated carbon.

PubMed

Ghaedi, M; Tavallali, H; Montazerozohori, M; Zahedi, E; Amirineko, M; Khodadoust, S; Karimipour, G

2012-11-01

In this work, two N/S-containing chelating agents 2-(4-methoxybenzylideneamino)thiophenol (2-4-MBAT) and 2-(4-chlorobenzylideneamino) benzenethiol (2-4-CBABT) were synthesized as new sorbents and were used for preconcentration of Zn(2+) and Cu(2+) ions in food and vegetable samples. In the proposed procedure, the trace amount of Zn(2+) and Cu(2+) ions from 250 mL of sample solution at pH = 5.0 was preconcentrated by 1 g of activated carbon (AC) loaded with 15 mg of 2-4-MBAT and 2-4-CBABT separately. The breakthrough volumes (maximum sample volume that their metal ions quantitatively can be enriched) for solid-phase extraction (SPE) procedure based on the AC modified with 2-4-MBAT and 2-4-CBABT were 800 and 750 mL, respectively. The sorbed Zn(2+) and Cu(2+) ions were efficiently eluted by 8 mL of 4 mol L(-1) HNO(3) and preconcentration factor of 112.5 and 93.7 and experimental enhancement factor of 30 and 35 ions were obtained for Zn(2+) and Cu(2+), respectively. The application of this enrichment procedure allowed the extraction of trace metal ions with recoveries exceeding of 90%.

Pancreaticoduodenectomy: a rare procedure for the management of complex pancreaticoduodenal injuries.

PubMed

Asensio, Juan A; Petrone, Patrizio; Roldán, Gustavo; Kuncir, Eric; Demetriades, Demetrios

2003-12-01

Pancreaticoduodenectomy (Whipple's procedure) is a formidable procedure when undertaken for severe pancreaticoduodenal injury. The purposes of this study were to review our experience with this procedure for trauma; to classify injury grades for both pancreatic and duodenal injuries in patients undergoing pancreaticoduodenectomy according to the American Association for the Surgery of Trauma-Organ Injury Scale for pancreatic and duodenal injury; and to validate existing indications for performance of this procedure. We performed a retrospective 126-month study (May 1992 to December 2002) of all patients admitted with proven complex pancreaticoduodenal injuries requiring pancreaticoduodenectomy. Eighteen patients were included; mean age was 32 +/- 12 years (SD), mean Revised Trauma Score was 6.84 +/- 2.13 (SD), and mean Injury Severity Score was 27 +/- 8 (SD). There were 17 penetrating injuries (94%) and 1 blunt injury (6%). One of 18 patients had an emergency department thoracotomy and died (100% mortality); 5 of the remaining 17 patients required operating room thoracotomies, and only 1 survived (80% mortality). There was 1 AAST-OIS pancreas grade IV injury, and there were 17 pancreas grade V injuries and 18 AAST-OIS duodenum grade V injuries. Indications for pancreaticoduodenectomy were: massive uncontrollable retropancreatic hemorrhage, 13 patients (72%); massive unreconstructable injury to the head of the pancreas/main pancreatic duct and intrapancreatic portion/distal common bile duct, 18 patients (100%); and massive unreconstructable injury, 18 patients (100%). Mean estimated blood loss was 6,888 +/- 7,866 mL, and overall survival was 67% (12 of 18 patients). Complex pancreaticoduodenal injuries requiring pancreaticoduodenectomy (Whipple's procedure) are uncommon but highly lethal; virtually all are classified as AAST-OIS grade V for both pancreas and duodenum. Current indications for performance of pancreaticoduodenectomy are valid and should be strictly applied during procedure selection.

Two-Year Outcomes of Surgical Treatment of Moderate Ischemic Mitral Regurgitation.

PubMed

Michler, Robert E; Smith, Peter K; Parides, Michael K; Ailawadi, Gorav; Thourani, Vinod; Moskowitz, Alan J; Acker, Michael A; Hung, Judy W; Chang, Helena L; Perrault, Louis P; Gillinov, A Marc; Argenziano, Michael; Bagiella, Emilia; Overbey, Jessica R; Moquete, Ellen G; Gupta, Lopa N; Miller, Marissa A; Taddei-Peters, Wendy C; Jeffries, Neal; Weisel, Richard D; Rose, Eric A; Gammie, James S; DeRose, Joseph J; Puskas, John D; Dagenais, François; Burks, Sandra G; El-Hamamsy, Ismail; Milano, Carmelo A; Atluri, Pavan; Voisine, Pierre; O'Gara, Patrick T; Gelijns, Annetine C

2016-05-19

In a trial comparing coronary-artery bypass grafting (CABG) alone with CABG plus mitral-valve repair in patients with moderate ischemic mitral regurgitation, we found no significant difference in the left ventricular end-systolic volume index (LVESVI) or survival after 1 year. Concomitant mitral-valve repair was associated with a reduced prevalence of moderate or severe mitral regurgitation, but patients had more adverse events. We now report 2-year outcomes. We randomly assigned 301 patients to undergo either CABG alone or the combined procedure. Patients were followed for 2 years for clinical and echocardiographic outcomes. At 2 years, the mean (±SD) LVESVI was 41.2±20.0 ml per square meter of body-surface area in the CABG-alone group and 43.2±20.6 ml per square meter in the combined-procedure group (mean improvement over baseline, -14.1 ml per square meter and -14.6 ml per square meter, respectively). The rate of death was 10.6% in the CABG-alone group and 10.0% in the combined-procedure group (hazard ratio in the combined-procedure group, 0.90; 95% confidence interval, 0.45 to 1.83; P=0.78). There was no significant between-group difference in the rank-based assessment of the LVESVI (including death) at 2 years (z score, 0.38; P=0.71). The 2-year rate of moderate or severe residual mitral regurgitation was higher in the CABG-alone group than in the combined-procedure group (32.3% vs. 11.2%, P<0.001). Overall rates of hospital readmission and serious adverse events were similar in the two groups, but neurologic events and supraventricular arrhythmias remained more frequent in the combined-procedure group. In patients with moderate ischemic mitral regurgitation undergoing CABG, the addition of mitral-valve repair did not lead to significant differences in left ventricular reverse remodeling at 2 years. Mitral-valve repair provided a more durable correction of mitral regurgitation but did not significantly improve survival or reduce overall adverse events or readmissions and was associated with an early hazard of increased neurologic events and supraventricular arrhythmias. (Funded by the National Institutes of Health and Canadian Institutes of Health Research; ClinicalTrials.gov number, NCT00806988.).

Trainees do not negatively impact the institutional learning curve for robotic prostatectomy as characterized by operative time, estimated blood loss, and positive surgical margin rate.

PubMed

Schroeck, Florian R; de Sousa, Chiquita A Palha; Kalman, Ross A; Kalia, Maitri S; Pierre, Sean A; Haleblian, George E; Sun, Leon; Moul, Judd W; Albala, David M

2008-04-01

We evaluated the learning curves and perioperative outcomes of an experienced laparoscopic surgeon and his trainees to assess our structured teaching program. We retrieved 383 patients undergoing robot-assisted laparoscopic prostatectomy (RALP) from our database. Trainees completed a structured teaching program and were categorized as early (days 0 to 232), mid (days 566 to 797), and late (days 825 to 1218) according to the time period in which they were working with the mentor. We compared operative times, estimated blood loss (EBL), and positive surgical margin (PSM) rates between the trainees and the mentor (Mann-Whitney and Chi-square test). Association of EBL, body mass index (BMI), and prostate weight with operative time was evaluated in multivariate linear regression analysis. Median operative times of the early, mid, and late trainees (258, 220, and 200 minutes) significantly decreased and were similar to the corresponding senior surgeon's (254, 242, and 180 minutes). Operative times decreased with lower BMI, EBL, and prostate weight (P = 0.006, P <0.001, and P <0.001, respectively). Overall, EBL (150 mL vs. 150 mL, P = 0.215) and PSM rates (20% vs. 18.6%, P = 0.741) did not differ between the mentor and the trainees. A structured teaching program for RALP is effective and trainees are able to adopt the increased efficiency and skills of their mentor. Lower BMI, EBL, and prostate weight were associated with shorter operative times. Trainees performing the procedure did not negatively affect EBL and positive surgical margin rate.

Can Tranexamic Acid Reduce Blood Loss during Major Cardiac Surgery? A Pilot Study.

PubMed

Compton, Frances; Wahed, Amer; Gregoric, Igor; Kar, Biswajit; Dasgupta, Amitava; Tint, Hlaing

2017-09-01

We examined the effectiveness of tranexamic acid in preventing intraoperative blood loss during major cardiac surgery. Out of initial 81 patients undergoing major cardiac surgery (both coronary artery bypass and valve repair procedures) at our teaching hospital, sixty-seven patients were selected for this study. We compared estimated blood loss, decrease in percent hemoglobin and hematocrit following surgery between two groups of patients (none of them received any blood product during surgery), one group receiving no tranexamic acid (n=17) and another group receiving tranexamic acid (n=25). In the second study, we combined these patients with patients receiving modest amounts of blood products (1-2 unit) and compared these parameters between two groups of patients (25 patients received no tranexamic acid, 42 patients received tranexamic acid). In patients who received no blood product during surgery, those who received no tranexamic acid showed statistically significant (independent t-test two tailed at p <0.05) reduced estimated blood loss (mean: 713.5 mL, SD: 351.6, n=17) compared to those who received tranexamic acid (mean: 987.2 mL, SD: 459.9, n=25). We observed similar results when the patients receiving no blood products and patients receiving modest amount of blood products were combined based on the use of tranexamic acid or not. No statistically significant difference was observed in percent reduced hemoglobin or hematocrit following surgery in any group of patients. We conclude that intraoperative antifibrinolytic therapy with tranexamic acid does not reduce intraoperative blood loss during major cardiac surgery which contradicts popular belief. © 2017 by the Association of Clinical Scientists, Inc.

Impact of thoracic surgery on esophageal motor function—Evaluation by high resolution manometry

PubMed Central

Kandulski, Arne; Malfertheiner, Peter; Riedel, Sandra; Zardo, Patrick; Hachenberg, Thomas; Schreiber, Jens

2017-01-01

Background Alteration of esophageal function is a potential risk factor for postoperative complications in thoracic surgery. This prospective study investigates esophageal motility and function during and after thoracic procedures via high resolution manometry (HRM) and impedance technology with spatiotemporal representation of pressure data. Methods Twelve consecutive patients eligible for elective thoracic surgery underwent preoperative and postoperative (48 hours and 7 days) esophageal HRM. Swallowing acts were carried out with 5 mL of water, 10 mL of water and 1 cm3 bread in physiological posture to evaluate distal contraction integral (DCI). Length and location of contractile integrity breaks were measured by investigators blinded to the form of surgical intervention. The impact of surgical procedures on esophageal motility was quantified according to current Chicago Classification (CC) criteria. Pre-, intra- and postoperative 24-hour multi-channel impedance pH–metry (MII-pH) was performed to further analyze gastroesophageal reflux patterns. Results All patients were investigated 48 hours prior to and 7 days after thoracic procedures, with a total of n=675 swallowing acts being included in our study. Increased motility patterns of the tubular esophagus occurred temporally 48 hours postoperatively. DCI 48 hours after surgery increased significantly (5 mL, P=0.049; solid, P=0.014) and returned to baseline values after seven days (5 mL, P=0.039; solid, P=0.039). Break length was significantly reduced 48 hours postoperatively, especially in the proximal esophageal segment (transition zone). Follow-up measurements after another week were comparable to preoperative baseline findings. The perioperative MII-pH measurement showed numerous artifacts caused by intubation and ventilation during surgery also with increasing short and frequent acidic reflux episodes. Conclusions Thoracic procedures cause a transient modulation of esophageal peristalsis with postoperative increased contractility of the tubular esophagus, presumably without affecting intraesophageal reflex arcs. Although limited by the number of patients, we can conclude on our data that postoperative esophageal hypomotility is unlikely to promote secondary pulmonary complications. PMID:28740669

Perceived levels of pain associated with bone marrow aspirates and biopsies.

PubMed

Talamo, Giampaolo; Liao, Jason; Joudeh, Jamal; Lamparella, Nicholas E; Dinh, Hoang; Malysz, Jozef; Ehmann, W Christopher

2012-01-01

Little is known about the degree of pain experienced by patients undergoing a bone marrow aspiration and biopsy (BMAB). To evaluate the effectiveness of several strategies aimed at reducing the pain score. We conducted a retrospective analysis of 258 consecutive adult patients who underwent BMAB via 6 different approaches, the first 5 of which were performed by one physician. Group A received local anesthesia with 1% lidocaine hydrochloride (5 mL) and a 5-minute wait time before the procedure; group B received local anesthesia with a double dose (10 mL) of lidocaine; group C received 5 mL of local anesthesia with a 10-minute wait; group D received 5 mL of local anesthesia plus a topical spray with ethyl chloride; group E received oral analgesia and anxiolysis 30 minutes before the procedure in addition to the group A dosage of lidocaine; and group F received the same anesthesia as did group A, but the BMAD was performed by a less experienced practitioner. On a 0 to 10 scale, the mean pain level among the 258 patients was 3.2 (standard deviation = 2.6). Rate of complications was low (<1%). Several strategies failed to improve the pain level, including the administration of a double dose of local anesthesia, waiting longer for the anesthesia effect, and the additional use of a topical anesthetic spray or oral analgesia and anxiolysis. Pain levels were not increased when the procedure was done by a less experienced practitioner. Younger age and female gender were associated with higher pain levels. Given that the average level of perceived pain during BMAB is low to moderate (approximately 3 on a 0-10 scale), the routine use of conscious sedation for this procedure may not be indicated. Several strategies aimed at reducing the pain level, including doubling the dose of anesthesia and using an oral prophylactic regimen of analgesia and anxiolysis, failed to improve pain scores. Copyright © 2012 Elsevier Inc. All rights reserved.

Impact of thoracic surgery on esophageal motor function-Evaluation by high resolution manometry.

PubMed

Wäsche, Anja; Kandulski, Arne; Malfertheiner, Peter; Riedel, Sandra; Zardo, Patrick; Hachenberg, Thomas; Schreiber, Jens

2017-06-01

Alteration of esophageal function is a potential risk factor for postoperative complications in thoracic surgery. This prospective study investigates esophageal motility and function during and after thoracic procedures via high resolution manometry (HRM) and impedance technology with spatiotemporal representation of pressure data. Twelve consecutive patients eligible for elective thoracic surgery underwent preoperative and postoperative (48 hours and 7 days) esophageal HRM. Swallowing acts were carried out with 5 mL of water, 10 mL of water and 1 cm 3 bread in physiological posture to evaluate distal contraction integral (DCI). Length and location of contractile integrity breaks were measured by investigators blinded to the form of surgical intervention. The impact of surgical procedures on esophageal motility was quantified according to current Chicago Classification (CC) criteria. Pre-, intra- and postoperative 24-hour multi-channel impedance pH-metry (MII-pH) was performed to further analyze gastroesophageal reflux patterns. All patients were investigated 48 hours prior to and 7 days after thoracic procedures, with a total of n=675 swallowing acts being included in our study. Increased motility patterns of the tubular esophagus occurred temporally 48 hours postoperatively. DCI 48 hours after surgery increased significantly (5 mL, P=0.049; solid, P=0.014) and returned to baseline values after seven days (5 mL, P=0.039; solid, P=0.039). Break length was significantly reduced 48 hours postoperatively, especially in the proximal esophageal segment (transition zone). Follow-up measurements after another week were comparable to preoperative baseline findings. The perioperative MII-pH measurement showed numerous artifacts caused by intubation and ventilation during surgery also with increasing short and frequent acidic reflux episodes. Thoracic procedures cause a transient modulation of esophageal peristalsis with postoperative increased contractility of the tubular esophagus, presumably without affecting intraesophageal reflex arcs. Although limited by the number of patients, we can conclude on our data that postoperative esophageal hypomotility is unlikely to promote secondary pulmonary complications.

PREOPERATIVE COMPUTED TOMOGRAPHY VOLUMETRY AND GRAFT WEIGHT ESTIMATION IN ADULT LIVING DONOR LIVER TRANSPLANTATION

PubMed Central

PINHEIRO, Rafael S.; CRUZ-JR, Ruy J.; ANDRAUS, Wellington; DUCATTI, Liliana; MARTINO, Rodrigo B.; NACIF, Lucas S.; ROCHA-SANTOS, Vinicius; ARANTES, Rubens M; LAI, Quirino; IBUKI, Felicia S.; ROCHA, Manoel S.; D´ALBUQUERQUE, Luiz A. C.

2017-01-01

ABSTRACT Background: Computed tomography volumetry (CTV) is a useful tool for predicting graft weights (GW) for living donor liver transplantation (LDLT). Few studies have examined the correlation between CTV and GW in normal liver parenchyma. Aim: To analyze the correlation between CTV and GW in an adult LDLT population and provide a systematic review of the existing mathematical models to calculate partial liver graft weight. Methods: Between January 2009 and January 2013, 28 consecutive donors undergoing right hepatectomy for LDLT were retrospectively reviewed. All grafts were perfused with HTK solution. Estimated graft volume was estimated by CTV and these values were compared to the actual graft weight, which was measured after liver harvesting and perfusion. Results: Median actual GW was 782.5 g, averaged 791.43±136 g and ranged from 520-1185 g. Median estimated graft volume was 927.5 ml, averaged 944.86±200.74 ml and ranged from 600-1477 ml. Linear regression of estimated graft volume and actual GW was significantly linear (GW=0.82 estimated graft volume, r2=0.98, slope=0.47, standard deviation of 0.024 and p<0.0001). Spearman Linear correlation was 0.65 with 95% CI of 0.45 - 0.99 (p<0.0001). Conclusion: The one-to-one rule did not applied in patients with normal liver parenchyma. A better estimation of graft weight could be reached by multiplying estimated graft volume by 0.82. PMID:28489167

On the asymptotic standard error of a class of robust estimators of ability in dichotomous item response models.

PubMed

Magis, David

2014-11-01

In item response theory, the classical estimators of ability are highly sensitive to response disturbances and can return strongly biased estimates of the true underlying ability level. Robust methods were introduced to lessen the impact of such aberrant responses on the estimation process. The computation of asymptotic (i.e., large-sample) standard errors (ASE) for these robust estimators, however, has not yet been fully considered. This paper focuses on a broad class of robust ability estimators, defined by an appropriate selection of the weight function and the residual measure, for which the ASE is derived from the theory of estimating equations. The maximum likelihood (ML) and the robust estimators, together with their estimated ASEs, are then compared in a simulation study by generating random guessing disturbances. It is concluded that both the estimators and their ASE perform similarly in the absence of random guessing, while the robust estimator and its estimated ASE are less biased and outperform their ML counterparts in the presence of random guessing with large impact on the item response process. © 2013 The British Psychological Society.

The effect of phloroglucinol on pain in first-trimester surgical abortion: a double-blind randomized controlled study.

PubMed

Zhuang, Yaling; Zhu, Xiufang; Huang, Li-Li

2010-02-01

First-trimester surgical abortion is a common procedure. Pain control during this procedure is still an unsolved problem. In this randomized, double-blind placebo-controlled study, women presenting for first-trimester surgical abortion received intramuscular phloroglucinol (4 mL) or placebo (normal saline, 4 mL). Visual analog scales (VAS) for pain immediately and 30 min after the procedure and side effects of the drug were recorded. There was no significant difference between groups in the pain level immediately and 30 min after the procedure; 70.7% of the phloroglucinol group (n=58 cases) and 56.9% of the placebo group (n=58 cases ) reported mild pain; 27.6% and 34.5%, respectively, reported moderate pain; and 1.7% and 8.6%, respectively, reported severe pain. Thirty minutes after the procedure, the median pain score was reduced to 1.3 in both groups. Postoperative side effects were reported, but there was no significant difference between groups for nausea or vomiting and blood pressure. The use of this dose of phloroglucinol, during first-trimester abortion by suction evacuation under local anesthesia with lidocaine, did not relieve pain, but caused no side effects.

Sodium Bicarbonate-Ascorbic Acid Combination for Prevention of Contrast-Induced Nephropathy in Chronic Kidney Disease Patients Undergoing Catheterization.

PubMed

Komiyama, Kota; Ashikaga, Takashi; Inagaki, Dai; Miyabe, Tomonori; Arai, Marina; Yoshida, Kiyotaka; Miyazawa, Satoshi; Nakada, Akihiro; Kawamura, Iwanari; Masuda, Shinichiro; Nagamine, Sho; Hojo, Rintaro; Aoyama, Yuya; Tsuchiyama, Takaaki; Fukamizu, Seiji; Shibui, Takashi; Sakurada, Harumizu

2017-01-25

Sodium bicarbonate and ascorbic acid have been proposed to prevent contrast-induced nephropathy (CIN). The present study evaluated the effect of their combined use on CIN incidence.Methods and Results:We prospectively enrolled 429 patients with chronic kidney disease (CKD: baseline estimated glomerular filtration rate <60 mL/min/1.73 m 2 ) prior to elective coronary catheterization. CIN was defined as absolute (≥0.5 mg/dL) or relative (≥25%) increase in serum creatinine within 72 h. In the saline hydration (n=218) and combined sodium bicarbonate+ascorbic acid (n=211) groups, a total of 1,500-2,500 mL 0.9% saline was given before and after the procedure. In addition, the combination group received 20 mEq sodium bicarbonate and 3 g ascorbic acid i.v. before the procedure, followed by 2 g ascorbic acid after the procedure and a further 2 g after 12 h. There were no significant differences between the basic characteristics and contrast volume in the 2 groups. CIN occurred in 19 patients (8.7%) in the saline group, and in 6 patients (2.8%) in the combined treatment group (P=0.008). Combined sodium bicarbonate and ascorbic acid could prevent CIN following catheterization in CKD patients.

Direct puncture embolization of the internal iliac artery during cesarean delivery for pernicious placenta previa coexisting with placenta accreta.

PubMed

Chen, Zhenyu; Li, Ju; Shen, Jian; Jin, Jiaxi; Zhang, Wei; Zhong, Wan

2016-12-01

To evaluate direct puncture embolization of the internal iliac artery with hemostatic gelatin sponge particles to treat pernicious placenta previa coexisting with placenta accreta during cesarean delivery. A retrospective study was conducted of data from women with pernicious placenta previa and placenta accreta who underwent direct puncture embolization of the internal iliac artery during cesarean delivery at a center in China between September 1, 2013, and February 28, 2015. Information regarding surgical procedures, operative data, and outcomes during hospitalization were obtained from medical records. The procedure was successful in all 16 cases included. Mean operative time was 78 minutes (range 65-90) and mean estimated blood loss was 1550 mL (range 1000-2500). Complications such as fever, buttock pain, or acute limb ischemia were not observed. The procedure was performed after partial cystectomy for two patients with bladder invasion. Postoperative Doppler imaging indicated uterine recovery and normalized uterine blood flow in all patients. Direct puncture embolization of the internal iliac artery during cesarean delivery was a safe, effective, simple, and rapid method to control hemorrhage among women with pernicious placenta previa and placenta accreta. Copyright © 2016 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

Using Low Levels of Stochastic Vestibular Stimulation to Improve Balance Function

PubMed Central

Goel, Rahul; Kofman, Igor; Jeevarajan, Jerome; De Dios, Yiri; Cohen, Helen S.; Bloomberg, Jacob J.; Mulavara, Ajitkumar P.

2015-01-01

Low-level stochastic vestibular stimulation (SVS) has been associated with improved postural responses in the medio-lateral (ML) direction, but its effect in improving balance function in both the ML and anterior-posterior (AP) directions has not been studied. In this series of studies, the efficacy of applying low amplitude SVS in 0–30 Hz range between the mastoids in the ML direction on improving cross-planar balance function was investigated. Forty-five (45) subjects stood on a compliant surface with their eyes closed and were instructed to maintain a stable upright stance. Measures of stability of the head, trunk, and whole body were quantified in ML, AP and combined APML directions. Results show that binaural bipolar SVS given in the ML direction significantly improved balance performance with the peak of optimal stimulus amplitude predominantly in the range of 100–500 μA for all the three directions, exhibiting stochastic resonance (SR) phenomenon. Objective perceptual and body motion thresholds as estimates of internal noise while subjects sat on a chair with their eyes closed and were given 1 Hz bipolar binaural sinusoidal electrical stimuli were also measured. In general, there was no significant difference between estimates of perceptual and body motion thresholds. The average optimal SVS amplitude that improved balance performance (peak SVS amplitude normalized to perceptual threshold) was estimated to be 46% in ML, 53% in AP, and 50% in APML directions. A miniature patch-type SVS device may be useful to improve balance function in people with disabilities due to aging, Parkinson’s disease or in astronauts returning from long-duration space flight. PMID:26295807

Concentration-effect relationship of levodopa in patients with Parkinson's disease after oral administration of an immediate release and a controlled release formulation.

PubMed Central

Harder, S; Baas, H; Bergemann, N; Demisch, L; Rietbrock, S

1995-01-01

1. The relationship between plasma concentration of levodopa and motor-response was investigated in 12 patients with Parkinson's disease who showed marked response fluctuations, after a single oral dose of an immediate release (IR) formulation (100 mg levodopa/25 mg genserazide) and a controlled release (CR) formulation (300 mg levodopa/75 mg benserazide), using a double-blind, randomized, cross-over design. 2. The sum score of the Columbia University Rating Scale (CURS sigma) was used for pharmacodynamic assessment. A sigmoidal Emax-model was fitted to the data using a semiparametric pharmacokinetic/dynamic approach. 3. The dose-corrected AUC of levodopa after the IR-formulation was 27.5 (+/- 9.1 s.d.) ng ml-1 h per mg and 23.2 (+/- 4.6 s.d.) ng ml-1 h per mg after the CR-formulation. Cmax was 1714 (+/- 1027 s.d.) ng ml-1 after the IR-formulation and 1494 (+/- 383 s.d.) ng ml-1 after the CR-formulation. 4. With both preparations, the maximal response to levodopa (Emax) was a decrease in the CURS sigma rating of about 27 scores. Estimates of the EC50 of levodopa were 495 (+/- 144 s.d.) ng ml-1 (IR) and 1024 (+/- 502 s.d.) ng ml-1 (CR), respectively (95%-CI: 1.51-2.66, point estimator 1.95). The mean duration of the motor response was 1.9 (+/- 0.5 s.d.) h (IR) and 2.8 (+/- 0.7 s.d.) h (CR), respectively (95%-CI: 1.12-2.04, point estimator 1.53).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7756097

Evaluation of the effect of antiarthritic drugs on the secretion of proteoglycans by lapine chondrocytes using a novel assay procedure.

PubMed Central

Collier, S; Ghosh, P

1989-01-01

A new method is described for separating free 35SO4-- from 35SO4 labelled proteoglycans synthesised by rabbit articular chondrocytes cultured in the presence of excess 35SO4--. The procedure uses the low solubility product of barium sulphate to remove, by precipitation, free 35SO4-- from culture medium. Optimum recovery of 35SO4 labelled proteoglycans was achieved after papain digestion to release 35SO4-glycosaminoglycans, and addition of chondroitin sulphate before the precipitation step. Using this assay, we studied the effect of six drugs-indomethacin, diclofenac, sodium pentosan polysulphate, glycosaminoglycan polysulphate ester, tiaprofenic acid, and ketoprofen-on the secretion into the medium of labelled proteoglycans by lapine chondrocytes. The six drugs were tested at 0.1, 1, 10, 50, and 100 micrograms/ml over four consecutive 48 hour culture periods. A consistent concentration-response pattern was found for the four non-steroidal anti-inflammatory drugs (NSAIDs) studied. Generally they inhibited proteoglycan secretion at 50 and 100 micrograms/ml but had no effect at lower concentrations. Inhibition of secretion was strongest with indomethacin and diclofenac at 50 and 100 micrograms/ml. In contrast with the NSAIDs studied, the two sulphated polysaccharides (sodium pentosan polysulphate and glycosaminoglycan polysulphate ester) at low concentrations increased proteoglycan secretion by chondrocytes, with maximal stimulation occurring at 1 microgram/ml. Sodium pentosan polysulphate, but not glycosaminoglycan polysulphate ester, showed inhibitory activity at 50 and 100 micrograms/ml. PMID:2471470

Renal Insufficiency After Contrast Media Administration Trial II (REMEDIAL II): RenalGuard System in high-risk patients for contrast-induced acute kidney injury.

PubMed

Briguori, Carlo; Visconti, Gabriella; Focaccio, Amelia; Airoldi, Flavio; Valgimigli, Marco; Sangiorgi, Giuseppe Massimo; Golia, Bruno; Ricciardelli, Bruno; Condorelli, Gerolama

2011-09-13

The RenalGuard System, which creates high urine output and fluid balancing, may be beneficial in preventing contrast-induced acute kidney injury. The Renal Insufficiency After Contrast Media Administration Trial II (REMEDIAL II) trial is a randomized, multicenter, investigator-driven trial addressing the prevention of contrast-induced acute kidney injury in high-risk patients. Patients with an estimated glomerular filtration rate ≤30 mL · min(-1) · 1.73 m(-2) and/or a risk score ≥11 were randomly assigned to sodium bicarbonate solution and N-acetylcysteine (control group) or hydration with saline and N-acetylcysteine controlled by the RenalGuard System and furosemide (RenalGuard group). The primary end point was an increase of ≥0.3 mg/dL in the serum creatinine concentration at 48 hours after the procedure. The secondary end points included serum cystatin C kinetics and rate of in-hospital dialysis. Contrast-induced acute kidney injury occurred in 16 of 146 patients in the RenalGuard group (11%) and in 30 of 146 patients in the control group (20.5%; odds ratio, 0.47; 95% confidence interval, 0.24 to 0.92). There were 142 patients (48.5%) with an estimated glomerular filtration rate ≤30 mL · min(-1) · 1.73 and 149 patients (51.5%) with only a risk score ≥11. Subgroup analysis according to inclusion criteria showed a similarly lower risk of adverse events (estimated glomerular filtration rate ≤30 mL · min(-1) · 1.73 m(-2): odds ratio, 0.44; risk score ≥11: odds ratio, 0.45; P for interaction=0.97). Changes in cystatin C at 24 hours (0.02±0.32 versus -0.08±0.26; P=0.002) and 48 hours (0.12±0.42 versus 0.03±0.31; P=0.001) and the rate of in-hospital dialysis (4.1% versus 0.7%; P=0.056) were higher in the control group. RenalGuard therapy is superior to sodium bicarbonate and N-acetylcysteine in preventing contrast-induced acute kidney injury in high-risk patients. URL: http://www.clinicaltrial.gov. Unique identifier: NCT01098032.

THE PHYSIOLOGICAL SIGNIFICANCE OF THE CORTIOOSTEROIDS IN PAROTID FLUID.

DTIC Science & Technology

A highly sensitive and highly specific technique was devised, utilizing four chromatographic procedures, for the measurement of parotid fluid...cortisol and cortisone on 5 ml of parotid fluid, and plasma cortisol on 1 ml of plasma. In addition techniques are described for measuring plasma...derivative technique is high purified immediately before its use, blank values are too high for the low values found in parotid saliva. Blank values

Randomized trial comparing overnight preoperative fasting period Vs oral administration of apple juice at 06:00-06:30 am in pediatric orthopedic surgical patients.

PubMed

Castillo-Zamora, Carlos; Castillo-Peralta, Luz A; Nava-Ocampo, Alejandro A

2005-08-01

We aimed to evaluate the efficacy of clear liquids orally administered at 06:00-06:30 am on the morning of surgery to reduce prolonged preoperative fasting periods. After obtaining informed parental consent, 100 children undergoing scheduled orthopedic surgical procedures, ASA I-II, were randomly allocated to two groups. In group 1, children underwent the typical overnight preoperative period and patients in group 2 received a commercial brand of apple juice (glucose 28 g in 250 ml) at 06:00-06:30 am on the day of surgery. Patients <3 years old received 15 ml.kg(-1) and older children 10 ml.kg(-1) to a maximum volume of 250 ml. All patients underwent overnight fasting for milk and solids. Fasting time was 4.8 +/- 2.1 h (ranging from 3 to 11 h) in the group receiving apple juice at 06:00-06:30 am and 13.2 +/- 3.3 h (ranging from 5 to 19 h) in the overnight-fasting group (P < 0.05; 95% CI: -9.6 to -7.4 h). More patients were irritable (odds ratio, OR 4.5; 95% CI: 1.9-10.8) and dehydrated (OR 21.6; 95% CI: 5.9-79.0) in the overnight-fasting group. Glucose levels <2.7 mmol.l(-1) (50 mg.dl(-1)) were not reported in any case. A 15 ml.kg(-1) of apple juice for patients of <3 years of age or 10 ml.kg(-1) for older children, at 06:00-06:30 am of the surgical morning is a simple procedure to prevent dehydration and to produce positive behavior in low-risk, pediatric surgical patients.

Latissimus dorsi flap for total autologous immediate breast reconstruction without implants.

PubMed

Santanelli di Pompeo, Fabio; Laporta, Rosaria; Sorotos, Michail; Pagnoni, Marco; Falesiedi, Federica; Longo, Benedetto

2014-12-01

The latissimus dorsi flap provides suitable recipient tissue for fat transfer, with a good blood supply and a reasonable volume of host tissue to inject into. The authors present their experience with use of the pedicled latissimus dorsi flap for fat grafting in total autologous immediate breast reconstruction without implants. From 2010 to 2013, 23 patients underwent breast reconstruction with primary fat augmented latissimus dorsi flaps (21 unilateral procedures and two bilateral procedures). Mean patient age was 52.3 years (range, 39 to 68 years); mean body mass index was 24.77 kg/m2 (range, 21.5 to 28.7 kg/m2). Fat was harvested using the Coleman technique with 10-ml syringes and injected into the adipose layer and muscle fascia of the latissimus dorsi flap skin paddle with 1-ml syringes. The mean size of the harvested skin paddle was 19.7 × 11.04 cm (range, 18 × 10 cm to 21 × 12 cm). Mean operative time was 2.62 hours (range, 2.10 to 3.20 hours) and 4.12 hours (range, 4.10 to 4.15 hours) for unilateral and bilateral reconstructions, respectively. Mean harvested fat volume was 126 ml (range, 90 to 180 ml), and mean injected fat volume was 101 ml (range, 60 to 150 ml). All flaps healed uneventfully, no seroma occurred at the flap donor-site, and no fat grafting-related complications were observed. To the best of the authors' knowledge, this is the first report in which fat transfer was used to achieve immediate latissimus dorsi flap volume augmentation as an alternative for total autologous reconstruction, avoiding implant-related complications.

Specific radioisotopic assay for cholinesterase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Talbot, B.G.; Anderson, D.R.; Harris, L.W.

1992-02-01

The authors have developed a radiometric method (1) for measuring cholinesterase (ChE) activity that uses 0.4 N perchloric acid (PCA), instead of p-dioxane (method 2), to denature the ChE and stop hydrolysis of acetyl-1-{sup 14}C-choline (ACh). The unreacted ACh is removed by IRP-69 cationic exchange resin suspended in water, instead of dioxane. The supernatant containing the hydrolysis product, {sup 14}C-acetic acid, is mixed with nonhazardous scintillation cocktail and counted. The incubation mixture of 1 is similar to 2 and contains 0.1 ml of buffer-salt solution 0.1 ml of guinea pig whole blood (WB)-water suspension and 0.1 ml of 3 mMmore » ACh solution. Procedures 1 and 2 were compared to a titragraphic assay for ChE activity; specific activity values of WB (mmol ACh hydrolyzed/ml/hr) were found to be 137.6, 72.4 and 135.0, respectively. When {sup 14}C-acetic acid was processed through procedures 1 and 2, significantly less {sup 14}C was found in the supernatant from 2, whereas all of the expected {sup 14}C was found in the supernatant from 1, suggesting that IRP-69 resin in dioxane will remove significant amounts of {sup 14}C-acetic acid.« less

Long-term outcomes and sac volume shrinkage after endovascular popliteal artery aneurysm repair.

PubMed

Piazza, M; Menegolo, M; Ferrari, A; Bonvini, S; Ricotta, J J; Frigatti, P; Grego, F; Antonello, M

2014-08-01

The aim was to evaluate long-term outcomes and sac volume shrinkage after endovascular popliteal artery aneurysm repair (EVPAR). This study was a retrospective review of all EVPAR cases between 1999 and 2012. Sac volume shrinkage, long-term patency, limb salvage, and survival were evaluated using Kaplan-Meier estimates. The association of anatomical and clinical characteristics with patency was evaluated using multivariate analysis. Forty-six EVPAR were carried out in 42 patients (mean age 78 years, 86% male; mean sac volume 45.5 ± 3.5 mL). In 93% of cases (n = 43) the procedure was elective, while in 7% of cases it was for rupture (n = 2) or acute thrombosis (n = 1). Of the 43 patients who underwent elective repair, 58% were asymptomatic and 42% symptomatic (14 claudication, 3 rest pain, and 1 compression symptoms). Technical success was 98%. Mean duration of follow-up was 56 ± 21 months. Primary patency at 1, 3, and 5 years was 82% (SE 2), 79% (SE 4), and 76% (SE 4), while secondary patency was 90% (SE 5), 85% (SE 4), and 82% (SE 1) respectively; at 5 years there was 98% limb salvage and an 84% survival rate. During follow-up 11 limbs had stent graft failure: six required conversion, one underwent amputation, and four continued with mild claudication. Of those with graft failure, 63% (7/11) occurred within the first year of follow-up. The mean aneurysm sac volume shrinkage between preoperative and 5-year post-procedure measurement was significant (45.5 ± 3.5 mL vs. 23.0 ± 5.0 mL; p < .001). Segment coverage >20 cm was a negative predictor for patency (HR 2.76; 95% CI 0.23; p = .032). EVPAR provides successful aneurysm exclusion with good long-term patency, excellent limb salvage, and survival rates. Close surveillance is nevertheless required, particularly during the first postoperative year. Patients requiring long segment coverage (>20 cm) may be at increased risk for failure. Copyright © 2014 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.

Development and validation of spectrophotometric methods for estimating amisulpride in pharmaceutical preparations.

PubMed

Sharma, Sangita; Neog, Madhurjya; Prajapati, Vipul; Patel, Hiren; Dabhi, Dipti

2010-01-01

Five simple, sensitive, accurate and rapid visible spectrophotometric methods (A, B, C, D and E) have been developed for estimating Amisulpride in pharmaceutical preparations. These are based on the diazotization of Amisulpride with sodium nitrite and hydrochloric acid, followed by coupling with N-(1-naphthyl)ethylenediamine dihydrochloride (Method A), diphenylamine (Method B), beta-naphthol in an alkaline medium (Method C), resorcinol in an alkaline medium (Method D) and chromotropic acid in an alkaline medium (Method E) to form a colored chromogen. The absorption maxima, lambda(max), are at 523 nm for Method A, 382 and 490 nm for Method B, 527 nm for Method C, 521 nm for Method D and 486 nm for Method E. Beer's law was obeyed in the concentration range of 2.5-12.5 microg mL(-1) in Method A, 5-25 and 10-50 microg mL(-1) in Method B, 4-20 microg mL(-1) in Method C, 2.5-12.5 microg mL(-1) in Method D and 5-15 microg mL(-1) in Method E. The results obtained for the proposed methods are in good agreement with labeled amounts, when marketed pharmaceutical preparations were analyzed.

Bacterioplankton in antarctic ocean waters during late austral winter: abundance, frequency of dividing cells, and estimates of production.

PubMed

Hanson, R B; Shafer, D; Ryan, T; Pope, D H; Lowery, H K

1983-05-01

Bacterioplankton productivity in Antarctic waters of the eastern South Pacific Ocean and Drake Passage was estimated by direct counts and frequency of dividing cells (FDC). Total bacterioplankton assemblages were enumerated by epifluorescent microscopy. The experimentally determined relationship between in situ FDC and the potential instantaneous growth rate constant (mu) is best described by the regression equation ln mu = 0.081 FDC - 3.73. In the eastern South Pacific Ocean, bacterioplankton abundance (2 x 10 to 3.5 x 10 cells per ml) and FDC (11%) were highest at the Polar Front (Antarctic Convergence). North of the Subantarctic Front, abundance and FDC were between 1 x 10 to 2 x 10 cells per ml and 3 to 5%, respectively, and were vertically homogeneous to a depth of 600 m. In Drake Passage, abundance (10 x 10 cells per ml) and FDC (16%) were highest in waters south of the Polar Front and near the sea ice. Subantarctic waters in Drake Passage contained 4 x 10 cells per ml with 4 to 5% FDC. Instantaneous growth rate constants ranged between 0.029 and 0.088 h. Using estimates of potential mu and measured standing stocks, we estimated productivity to range from 0.62 mug of C per liter . day in the eastern South Pacific Ocean to 17.1 mug of C per liter . day in the Drake Passage near the sea ice.

U.S. Air Force Operational Medicine: Using the Enterprise Estimating Supplies Program to Develop Materiel Solutions for the Aeromedical Evacuation In-Flight Kit (FFQDM)

DTIC Science & Technology

2011-05-04

0.04 $12.30 0.04 0.01 $3.08 C 6505013092742UM METOPROLOL TARTRATE INJ 1MG/ML 5ML AMPS 12S AM 3 1 0.03 0.00 $2.39 0.01 0.00 $0.80 A 6505010906797... METOPROLOL TARTRATE TAB 50MG 100S BT 1 1 0.34 0.10 $4.65 0.34 0.10 $4.65 C 6505015055813 MORPHINE SULF INJ 10MG/ML 1ML 10S PG 8 2 2.00 1.20 $82.32 0.50

Renal sympathetic denervation increases renal blood volume per cardiac cycle: a serial magnetic resonance imaging study in resistant hypertension.

PubMed

Delacroix, Sinny; Chokka, Ramesh G; Nelson, Adam J; Wong, Dennis T; Sidharta, Samuel; Pederson, Stephen M; Rajwani, Adil; Nimmo, Joanne; Teo, Karen S; Worthley, Stephen G

2017-01-01

Preclinical studies have demonstrated improvements in renal blood flow after renal sympathetic denervation (RSDN); however, such effects are yet to be confirmed in patients with resistant hypertension. Herein, we assessed the effects of RSDN on renal artery blood flow and diameter at multiple time points post-RSDN. Patients (n=11) with systolic blood pressures ≥160 mmHg despite taking three or more antihypertensive medications at maximum tolerated dose were recruited into this single-center, prospective, non-blinded study. Magnetic resonance imaging indices included renal blood flow and renal artery diameters at baseline, 1 month and 6 months. In addition to significant decreases in blood pressures ( p <0.0001), total volume of blood flow per cardiac cycle increased by 20% from 6.9±2 mL at baseline to 8.4±2 mL ( p =0.003) at 1 month and to 8.0±2 mL ( p =0.04) 6 months post-procedure, with no changes in the renal blood flow. There was a significant decrease in renal artery diameters from 7±2 mm at baseline to 6±1 mm ( p =0.03) at 1 month post-procedure. This decrease was associated with increases in maximum velocity of blood flow from 73±20 cm/s at baseline to 78±19 cm/s at 1 month post-procedure. Notably, both parameters reverted to 7±2 mm and 72±18 cm/s, respectively, 6 months after procedure. RSDN improves renal physiology as evidenced by significant improvements in total volume of blood flow per cardiac cycle. Additionally, for the first time, we identified a transient decrease in renal artery diameters immediately after procedure potentially caused by edema and inflammation that reverted to baseline values 6 months post-procedure.

Maximum Peak Systolic Velocity and Management of Highly Vascularized Retained Products of Conception.

PubMed

Van den Bosch, Thierry; Van Schoubroeck, Dominique; Timmerman, Dirk

2015-09-01

The purpose of this study was to evaluate blood loss and procedure-related complications during and after surgical removal of retained products of conception with high-velocity enhanced myometrial vascularity. We conducted a prospective study of 18 consecutive women with a diagnosis of retained products of conception and enhanced myometrial vascularity, with a peak systolic velocity (PSV) higher than 60 cm/s. All underwent ultrasound-guided surgical removal of the retained products under general anesthesia. Blood loss during the procedure was collected and recorded. The removed tissue was sent for histologic examination. An ultrasound examination was repeated within 24 hours. Five patients had retained products of conception after a term delivery, 1 after a second-trimester termination of pregnancy, 7 after a spontaneous first-trimester miscarriage, and 5 after a first-trimester termination elsewhere. The PSV in the area of enhanced myometrial vascularity at diagnosis ranged from 61.0 to 152.6 cm/s (mean, 104.9 cm/s). The estimated blood loss at surgery ranged from 20 to 1000 mL (mean, 200 mL). After surgery, the PSV in the myometrium dropped dramatically (≤30 cm/s in all but 1 case). In all cases, trophoblastic tissue was confirmed at histologic examination. Although surgical removal of retained products of conception was uneventful in most cases, heavy bleeding has to be anticipated in cases of high-velocity flow in the myometrium underlying residual trophoblastic tissue. Accordingly, in cases of high-velocity enhanced myometrial vascularity, we advocate surgical removal of the residual tissue under ultrasound guidance by an experienced surgeon and in the presence of a fully informed anesthetist. © 2015 by the American Institute of Ultrasound in Medicine.

A machine learning approach using EEG data to predict response to SSRI treatment for major depressive disorder.

PubMed

Khodayari-Rostamabad, Ahmad; Reilly, James P; Hasey, Gary M; de Bruin, Hubert; Maccrimmon, Duncan J

2013-10-01

The problem of identifying, in advance, the most effective treatment agent for various psychiatric conditions remains an elusive goal. To address this challenge, we investigate the performance of the proposed machine learning (ML) methodology (based on the pre-treatment electroencephalogram (EEG)) for prediction of response to treatment with a selective serotonin reuptake inhibitor (SSRI) medication in subjects suffering from major depressive disorder (MDD). A relatively small number of most discriminating features are selected from a large group of candidate features extracted from the subject's pre-treatment EEG, using a machine learning procedure for feature selection. The selected features are fed into a classifier, which was realized as a mixture of factor analysis (MFA) model, whose output is the predicted response in the form of a likelihood value. This likelihood indicates the extent to which the subject belongs to the responder vs. non-responder classes. The overall method was evaluated using a "leave-n-out" randomized permutation cross-validation procedure. A list of discriminating EEG biomarkers (features) was found. The specificity of the proposed method is 80.9% while sensitivity is 94.9%, for an overall prediction accuracy of 87.9%. There is a 98.76% confidence that the estimated prediction rate is within the interval [75%, 100%]. These results indicate that the proposed ML method holds considerable promise in predicting the efficacy of SSRI antidepressant therapy for MDD, based on a simple and cost-effective pre-treatment EEG. The proposed approach offers the potential to improve the treatment of major depression and to reduce health care costs. Copyright © 2013 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Robotic partial nephrectomy for renal cell carcinomas with venous tumor thrombus.

PubMed

Abaza, Ronney; Angell, Jordan

2013-06-01

To describe the first report of robotic partial nephrectomies (RPNs) for renal cell carcinoma (RCC) with venous tumor thrombus (VTT). Partial nephrectomy for RCC extending into the renal vein has been described in limited fashion, but such a complex procedure has not previously been reported in minimally-invasive fashion. We demonstrate the feasibility of robotic nephron-sparing surgery despite vein thrombi and the results of the initial four highly-selected patients to have undergone this novel procedure. Two patients underwent RPN for RCC with VTT involving intraparenchymal vein branches, and 2 others had VTT involving the main renal vein. Mean patient age was 65 years (range 50-74 years). Mean tumor size was 7.75 cm (range 4.3-12.8 cm) with mean RENAL (radius, exophytic/endophytic, nearness to collecting system, anterior/posterior, and location) nephrometry score of 9.75 (range 8-12). Mean warm ischemia time was 24.2 minutes (range 19-27 minutes) and mean estimated blood loss was 168.8 mL (range 100-300 mL). No patients required transfusion, and there were no intraoperative complications. No patients required conversion to open or standard laparoscopic surgery. All 4 patients were discharged home on the first postoperative day. A single postoperative complication occurred in 1 patient who was readmitted with an ileus that resolved spontaneously. All patients had negative surgical margins. Two patients developed metastatic disease on surveillance imaging. RPN in patients with VTT is safe and feasible in selected patients. Given the risk of metastatic disease in patients with pathologic stage T3a RCC, the role of nephron sparing requires further evaluation such that radical nephrectomy remains the standard of care. Copyright © 2013 Elsevier Inc. All rights reserved.

Laparoscopic radical hysterectomy with vaginectomy and reconstruction of vagina in patients with stage I of primary vaginal carcinoma.

PubMed

Ling, Bin; Gao, Zongxia; Sun, Minwen; Sun, Fanglin; Zhang, Aijun; Zhao, Weidong; Hu, Weiping

2008-04-01

The purpose of this study was to retrospectively evaluate the technique, feasibility and oncological safety of laparoscopic radical hysterectomy with vaginectomy and reconstruction of vagina in patients with stage I primary vaginal carcinomas. Between February 2003 and July 2004, four patients, that had needs of sexual life, aging from 41 to 61 years with stage I primary vaginal carcinoma located at the upper third or 2/3 of the vagina, were submitted to laparoscopic radical hysterectomy with vaginectomy and reconstruction of the vagina using the sigmoid colon. The average operative time was 305 min (range 260-350 min). The average estimated blood loss was 325 ml (range 250-400 ml), and the medial number of the lymph nodes removed was 16 (range 13-20). All surgical margins and nodes removed were negative histopathologically. There were no intra-operative and postoperative complications. The mean stay day after surgery was 7 days (range 6-8 days). The mean length of a neo-vagina was 13 cm (range 12-15 cm) and the introitus admitted two fingers in breadth. The mean follow-up was 46 months (range 40-54 months). All patients are clinically free of disease and have satisfactory sexual life. None require dilation of the introitus. During the first 6 months, all the patients had little complaints of excessive leucorrhoea. To our knowledge, this is the first reported laparoscopical radical surgery combined with reconstruction of the vagina in patients with early-stage primary vaginal cancer. Our results have demonstrated the oncological safety and feasibility of the laparoscopical procedure. Intermediate-term follow-up validates the adequacy of this procedure.

A validated stability indicating RP-HPLC method for estimation of Armodafinil in pharmaceutical dosage forms and characterization of its base hydrolytic product.

PubMed

Venkateswarlu, Kambham; Rangareddy, Ardhgeri; Narasimhaiah, Kanaka; Sharma, Hemraj; Bandi, Naga Mallikarjuna Raja

2017-01-01

The main objective of present study was to develop a RP-HPLC method for estimation of Armodafinil in pharmaceutical dosage forms and characterization of its base hydrolytic product. The method was developed for Armodafinil estimation and base hydrolytic products were characterized. The separation was carried out on C18 column by using mobile phase as mixture of water and methanol (45:55%v/v). Eluents were detected at 220nm at 1ml/min. Stress studies were performed with milder conditions followed by stronger conditions so as to get sufficient degradation around 20%. A total of five degradation products were detected and separated from analyte. The linearity of the proposed method was investigated in the range of 20-120µg/ml for Armodafinil. The detection limit and quantification limit was found to be 0.01183μg/ml and 0.035µg/ml respectively. The precision % RSD was found to be less than 2% and the recovery was between 98-102%. Armodafinil was found to be more sensitive to the base hydrolysis and yielded its carboxylic acid as degradant. The developed method was stability indicating assay, suitable to quantify Armodafinil in presence of possible degradants. The drug was sensitive to acid, base &photolytic stress and resistant to thermal &oxidation.

Trans-areola single-site endoscopic thyroidectomy: pilot study of 35 cases.

PubMed

Youben, Fan; Bo, Wu; Chunlin, Zhong; Jie, Kang; Bomin, Guo; Fan, Yang; Xianzhao, Deng; Qi, Zheng

2012-04-01

Endoscopic thyroidectomy via thoracic/breast approach is an acceptable and successful technique in Asia. This technique has the advantage of better cosmesis compared with open or even video-assisted thyroidectomy. Unfortunately, because of the need for three separate ports, conventional endoscopic thyroidectomy usually involves significantly more tissue dissection, and thus more injury to patients, limiting the popularity of this technique. We herein present 35 cases of trans-areola single-site endoscopic thyroidectomy (TASSET), which was first performed in 2009. Thirty-five patients who underwent TASSET for thyroid nodules from September 2009 to March 2011 were evaluated. The surgical outcomes of the surgery were retrospectively analyzed, including conversion, operative time, estimated blood loss, complications, length of stay, and patient satisfaction. Thirty-one of the 35 patients (88.5%) underwent successful TASSET, with subtotal lobectomy being the most common procedure. Median operative time for the surgery was 153.65 min (range 100-190 min). Estimated blood loss ranged from 20 to 40 mL. Length of postoperative stay ranged from 2 to 4 days (average 2.5 days). Visual analog scale scores were 0 to 4 without administration of analgesics. The complication rate was low (8.6%) and included one case of transient recurrent laryngeal nerve (RLN) palsy, one case of subcutaneous seroma, and one case of tracheal injury. All patients were satisfied with the cosmetic outcome after mean follow-up of 8 months. TASSET is feasible and safe, with great cosmetic benefits and less injury than other procedures. It may become an alternative procedure for treatment of patients with benign thyroid tumors, especially those with strong desire for cervical cosmesis.

First postoperative PSA is associated with outcomes in patients with node positive prostate cancer: Results from the SEARCH database.

PubMed

McDonald, Michelle L; Howard, Lauren E; Aronson, William J; Terris, Martha K; Cooperberg, Matthew R; Amling, Christopher L; Freedland, Stephen J; Kane, Christopher J

2018-05-01

To analyze factors associated with metastases, prostate cancer-specific mortality, and all-cause mortality in pN1 patients. We analyzed 3,642 radical prostatectomy patients within the Shared Equal Access Regional Cancer Hospital (SEARCH) database. Pathologic Gleason grade, number of lymph nodes (LN) removed, and first postoperative prostate-specific antigen (PSA) (<0.2 ng/ml or ≥0.2 ng/ml) were among covariates assessed. Cox regression was used to analyze the association between characteristics and survival outcomes. Kaplan-Meier was used to estimate survival in pN1 patients stratified by first postoperative PSA. Of 3,642 patients, 124 (3.4%) had pN1. There were 71 (60%) patients with 1 positive LN, 32 (27%) with 2 positive LNs, and 15 (13%) with ≥3. Among men with pN1, first postoperative PSA was<0.2ng/ml in 46 patients (51%) and ≥0.2ng/ml in 44 patients (49%). Univariable Cox regression determined pathological Gleason grade (P = 0.021), seminal vesicle invasion (P = 0.010), and first postoperative PSA ≥0.2 ng/ml (P = 0.005) were associated with metastases. First postoperative PSA ≥0.2ng/ml was associated with metastasis on multivariable analysis (P = 0.046). Log-rank analysis revealed a more favorable metastases-free survival in patients with a first postoperative PSA<0.2ng/ml (P = 0.001). Estimated 5-year metastases-free survival rate was 99% for patients with a first postoperative PSA<0.2ng/ml and 87% for ≥0.2ng/ml. pN1 patients with a first postoperative PSA ≥0.2ng/ml were more likely to develop metastases. First postoperative PSA may be useful in identifying pN1 patients who harbor distant disease and aid in secondary treatment decisions. Copyright © 2018 Elsevier Inc. All rights reserved.

The human jejunum has an endogenous microbiota that differs from those in the oral cavity and colon.

PubMed

Sundin, Olof H; Mendoza-Ladd, Antonio; Zeng, Mingtao; Diaz-Arévalo, Diana; Morales, Elisa; Fagan, B Matthew; Ordoñez, Javier; Velez, Philip; Antony, Nishaal; McCallum, Richard W

2017-07-17

The upper half of the human small intestine, known as the jejunum, is the primary site for absorption of nutrient-derived carbohydrates, amino acids, small peptides, and vitamins. In contrast to the colon, which contains 10 11 -10 12 colony forming units of bacteria per ml (CFU/ml), the normal jejunum generally ranges from 10 3 to 10 5  CFU per ml. Because invasive procedures are required to access the jejunum, much less is known about its bacterial microbiota. Bacteria inhabiting the jejunal lumen have been investigated by classical culture techniques, but not by culture-independent metagenomics. The lumen of the upper jejunum was sampled during enteroscopy of 20 research subjects. Culture on aerobic and anaerobic media gave live bacterial counts ranging from 5.8 × 10 3 CFU/ml to 8.0 × 10 6 CFU/ml. DNA from the same samples was analyzed by 16S rRNA gene-specific quantitative PCR, yielding values from 1.5 × 10 5 to 3.1 × 10 7 bacterial genomes per ml. When calculated for each sample, estimated bacterial viability ranged from effectively 100% to a low of 0.3%. 16S rRNA metagenomic analysis of uncultured bacteria by Illumina MiSeq sequencing gave detailed microbial composition by phylum, genus and species. The genera Streptococcus, Prevotella, Veillonella and Fusobacterium, were especially abundant, as well as non-oral genera including Escherichia, Klebsiella, and Citrobacter. The jejunum was devoid of the genera Alistipes, Ruminococcus, Faecalibacterium, and other extreme anaerobes abundant in the colon. In patients with higher bacterial loads, there was no significant change in microbial species composition. The jejunal lumen contains a distinctive bacterial population consisting primarily of facultative anaerobes and oxygen-tolerant obligate anaerobes similar to those found in the oral cavity. However, the frequent abundance of Enterobacteriaceae represents a major difference from oral microbiota. Although a few genera are shared with the colon, we found no evidence for retrograde movement of the most abundant colonic microbes to the jejunum. Some individuals had much higher bacterial loads, but this was not correlated with decreases in bacterial species diversity or other evidence of dysbiosis.

Estimating Time to ESRD Using Kidney Failure Risk Equations: Results From the African American Study of Kidney Disease and Hypertension (AASK)

PubMed Central

Grams, Morgan E.; Li, Liang; Greene, Tom H.; Tin, Adrienne; Sang, Yingying; Kao, W.H. Linda; Lipkowitz, Michael S.; Wright, Jackson T.; Chang, Alex R.; Astor, Brad C.; Appel, Lawrence J.

2014-01-01

Background Planning for renal replacement therapy, such as referral for arteriovenous fistula placement and transplantation, is often guided by level of estimated glomerular filtration rate (eGFR). The use of risk equations might enable more accurate estimation of time to end-stage renal disease (ESRD), thus improving patient care. Study Design Prospective observational study. Setting & Participants 1,094 participants in the African-American Study of Kidney Disease and Hypertension (AASK) cohort. Predictor Age, sex, urine protein-creatinine ratio ≥1 g/g, APOL1 high-risk status, and 3-year antecedent eGFR decline. Outcome Cumulative incidence of ESRD from five different starting points: eGFR values of 30 and 15 ml/min/1.73 m2, and a 5%, 10%, and 20% 1-year ESRD risk, estimated by a published, 4-variable kidney failure risk equation. Results There were 566 participants who developed an eGFR of 30 ml/min/1.73 m2, 244 who developed eGFR of 15 ml/min/1.73 m2, and 437, 336, and 259 who developed a 5%, 10%, and 20% 1-year ESRD risk, respectively. The 1-year cumulative incidence of ESRD was 4.3% from eGFR 30 ml/min/1.73 m2, 49.0% from eGFR 15 ml/min/1.73 m2, 6.7% from 5% ESRD risk, 15.0% from 10% ESRD risk, and 29% from 20% ESRD risk. From eGFR 30 ml/min/1.73 m2, there were several risk factors that predicted ESRD risk. From eGFR 15 ml/min/1.73 m2, only level of proteinuria did; median time to ESRD was 9 and 19 months in those with higher and lower proteinuria, respectively. Median times were less variable from corresponding ESRD risk thresholds. For example, median time to ESRD from 20% ESRD risk was 22 and 25 months among those with higher and lower proteinuria, respectively. Limitations Relatively homogeneous population of African Americans with hypertensive kidney disease. Conclusions The results of the present study suggest the potential benefit of incorporating kidney failure risk equations into clinical care, with selection of a specific threshold guided by its intended use. PMID:25441435

Combination of magnetic dispersive micro solid-phase extraction and supramolecular solvent-based microextraction followed by high-performance liquid chromatography for determination of trace amounts of cholesterol-lowering drugs in complicated matrices.

PubMed

Arghavani-Beydokhti, Somayeh; Rajabi, Maryam; Asghari, Alireza

2017-07-01

A novel, efficient, rapid, simple, sensitive, selective, and environmentally friendly method termed magnetic dispersive micro solid-phase extraction combined with supramolecular solvent-based microextraction (Mdμ-SPE-SSME) followed by high-performance liquid chromatography (HPLC) with UV detection is introduced for the simultaneous microextraction of cholesterol-lowering drugs in complicated matrices. In the first microextraction procedure, using layered double hydroxide (LDH)-coated Fe 3 O 4 magnetic nanoparticles, an efficient sample cleanup is simply and rapidly provided without the need for time-consuming centrifugation and elution steps. In the first step, desorption of the target analytes is easily performed through dissolution of the LDH-coated magnetic nanoparticles containing the target analytes in an acidic solution. In the next step, an emulsification microextraction method based on a supramolecular solvent is used for excellent preconcentration, ultimately resulting in an appropriate determination of the target analytes in real samples. Under the optimal experimental conditions, the Mdμ-SPE-SSME-HPLC-UV detection procedure provides good linearity in the ranges of 1.0-1500 ng mL -1 , 1.5-2000 ng mL -1 , and 2.0-2000 ng mL -1 with coefficients of determination of 0.995 or less, low limits of detection (0.3, 0.5, and 0.5 ng mL -1 ), and good extraction repeatabilities (relative standard deviations below 7.8%, n = 5) in deionized water for rosuvastatin, atorvastatin, and gemfibrozil, respectively. Finally, the proposed method is successfully applied for the determination of the target analytes in complicated matrices. Graphical Abstract Mdμ-SPE-SSME procedure.

How useful is determination of anti-factor Xa activity to guide bridging therapy with enoxaparin? A pilot study.

PubMed

Hammerstingl, Christoph; Omran, Heyder; Tripp, Christian; Poetzsch, Bernd

2009-02-01

Low-molecular-weight heparins (LMWH) are commonly used as peri-procedural bridging anticoagulants. The usefulness of measurement of anti-factor Xa activity (anti-Xa) to guide bridging therapy with LMWH is unknown. It was the objective of this study to determine levels of anti-Xa during standard bridging therapy with enoxaparin, and to examine predictors for residual anti-Xa. Consecutive patients receiving enoxaparin at a dosage of 1 mg/kg body weight/12 hours for temporary interruption of phenprocoumon were prospectively enrolled to the study. Blood-samples were obtained 14 hours after LMWH-application immediately pre- procedurally. Procedural details, clinical and demographic data were collected and subsequently analyzed. Seventy patients were included (age 75.2 +/- 10.8 years, Cr Cl 55.7 +/- 21.7ml/min, body mass index [BMI] 27.1 +/- 4.9). LMWH- therapy was for a mean of 4.2 +/- 1.6 days; overall anti-Xa was 0.58 +/- 0.32 U/ml. In 37 (52.8%) of patients anti-Xa was > or U/ml, including 10 (14.3%) patients with anti-Xa > 1U/ml. Linear regression analysis of single variables and logistic multivariable regression analysis failed to prove a correlation between anti-Xa and single or combined factors. No major bleeding, no thromboembolism and four (5.7%) minor haemorrhages were observed. When bridging OAC with therapeutic doses of enoxaparin a high percentage of patients undergo interventions with high residual anti-Xa. The levels of anti-Xa vary largely and are independent of single or combined clinical variables. Since the anti-Xa-related outcome of patients receiving bridging therapy with LMWH is not investigated, no firm recommendation on the usefulness of monitoring of anti-Xa can be given at this stage.

Syringe size: does it matter in physician-performed procedures?

PubMed

Michael, Adrian A; Moorjani, Gautam R; Peisajovich, Andres; Park, Kye S; Sibbitt, Wilmer L; Bankhurst, Arthur D

2009-03-01

We hypothesized that the size of syringe influenced needle control in physician-performed procedures. Operators were tested for their ability to control a 1-, 3-, 5-, 10-, and 20-mL syringe and equivalent sizes of the new safety device, the reciprocating procedure device (RPD), using the quantitative needle-based displacement method. Three hundred twenty clinical syringe procedures were then randomized to either a 3- or 10-mL conventional syringe or to a 3- or 10-mL RPD. Patient pain was measured with the Visual Analog Pain Scale (VAPS). Increasing syringe size was associated with the undesirable characteristic of unintended forward penetration (loss of control of the needle in the forward direction) (r(2) = 0.97, slope = 2.14, 95% CI: 1.54-2.76, P < 0.002), and unintended retraction (loss of control of the needle in the reverse direction) (r(2) = 0.97, slope 2.15, 95% CI: 1.54-2.76, P < 0.002). In addition, 2-handed operation of a syringe resulted in greater control than 1-handed operation of a syringe (P < 0.001). When 1-handed operation was required, the RPD control syringe reduced unintended penetration by 52.3% (P >or= 0.001), unintended retraction by 56.8% (P >or= 0.001), and patient pain by 54.7% (P >or= 0.001) at each device size. For greater safety and control when operating the conventional syringe, smaller syringe sizes and 2 hands instead of 1 hand should be used whenever possible. If 1-handed operation of a syringe is necessary, a safety technology like the RPD control syringe should be used.

Pharmacokinetics of meropenem after intravenous, intramuscular and subcutaneous administration to cats.

PubMed

Albarellos, Gabriela A; Montoya, Laura; Passini, Sabrina M; Lupi, Martín P; Lorenzini, Paula M; Landoni, María F

2016-12-01

The aim of the study was to describe the pharmacokinetics and predicted efficacy of meropenem after intravenous (IV), intramuscular (IM) and subcutaneous (SC) administration to cats at a single dose of 10 mg/kg. Five adult healthy cats were used. Blood samples were withdrawn at predetermined times over a 12 h period. Meropenem concentrations were determined by microbiological assay. Pharmacokinetic analyses were performed with computer software. Initial estimates were determined using the residual method and refitted by non-linear regression. The time that plasma concentrations were greater than the minimum inhibitory concentration (T >MIC) was estimated by applying bibliographic MIC values and meropenem MIC breakpoint. Maximum plasma concentrations of meropenem were 101.02 µg/ml (C p(0) , IV), 27.21 µg/ml (C max , IM) and 15.57 µg/ml (C max , SC). Bioavailability was 99.69% (IM) and 96.52 % (SC). Elimination half-lives for the IV, IM and SC administration were 1.35, 2.10 and 2.26 h, respectively. Meropenem, when administered to cats at a dose of 10 mg/kg q12h,, is effective against bacteria with MIC values of 6 μg/ml, 7 μg/ml and 10 μg/ml for IV, IM and SC administration, respectively. However, clinical trials are necessary to confirm clinical efficacy of the proposed dosage regimen. © The Author(s) 2015.

Improving Depth, Energy and Timing Estimation in PET Detectors with Deconvolution and Maximum Likelihood Pulse Shape Discrimination

PubMed Central

Berg, Eric; Roncali, Emilie; Hutchcroft, Will; Qi, Jinyi; Cherry, Simon R.

2016-01-01

In a scintillation detector, the light generated in the scintillator by a gamma interaction is converted to photoelectrons by a photodetector and produces a time-dependent waveform, the shape of which depends on the scintillator properties and the photodetector response. Several depth-of-interaction (DOI) encoding strategies have been developed that manipulate the scintillator’s temporal response along the crystal length and therefore require pulse shape discrimination techniques to differentiate waveform shapes. In this work, we demonstrate how maximum likelihood (ML) estimation methods can be applied to pulse shape discrimination to better estimate deposited energy, DOI and interaction time (for time-of-flight (TOF) PET) of a gamma ray in a scintillation detector. We developed likelihood models based on either the estimated detection times of individual photoelectrons or the number of photoelectrons in discrete time bins, and applied to two phosphor-coated crystals (LFS and LYSO) used in a previously developed TOF-DOI detector concept. Compared with conventional analytical methods, ML pulse shape discrimination improved DOI encoding by 27% for both crystals. Using the ML DOI estimate, we were able to counter depth-dependent changes in light collection inherent to long scintillator crystals and recover the energy resolution measured with fixed depth irradiation (~11.5% for both crystals). Lastly, we demonstrated how the Richardson-Lucy algorithm, an iterative, ML-based deconvolution technique, can be applied to the digitized waveforms to deconvolve the photodetector’s single photoelectron response and produce waveforms with a faster rising edge. After deconvolution and applying DOI and time-walk corrections, we demonstrated a 13% improvement in coincidence timing resolution (from 290 to 254 ps) with the LFS crystal and an 8% improvement (323 to 297 ps) with the LYSO crystal. PMID:27295658

Improving Depth, Energy and Timing Estimation in PET Detectors with Deconvolution and Maximum Likelihood Pulse Shape Discrimination.

PubMed

Berg, Eric; Roncali, Emilie; Hutchcroft, Will; Qi, Jinyi; Cherry, Simon R

2016-11-01

In a scintillation detector, the light generated in the scintillator by a gamma interaction is converted to photoelectrons by a photodetector and produces a time-dependent waveform, the shape of which depends on the scintillator properties and the photodetector response. Several depth-of-interaction (DOI) encoding strategies have been developed that manipulate the scintillator's temporal response along the crystal length and therefore require pulse shape discrimination techniques to differentiate waveform shapes. In this work, we demonstrate how maximum likelihood (ML) estimation methods can be applied to pulse shape discrimination to better estimate deposited energy, DOI and interaction time (for time-of-flight (TOF) PET) of a gamma ray in a scintillation detector. We developed likelihood models based on either the estimated detection times of individual photoelectrons or the number of photoelectrons in discrete time bins, and applied to two phosphor-coated crystals (LFS and LYSO) used in a previously developed TOF-DOI detector concept. Compared with conventional analytical methods, ML pulse shape discrimination improved DOI encoding by 27% for both crystals. Using the ML DOI estimate, we were able to counter depth-dependent changes in light collection inherent to long scintillator crystals and recover the energy resolution measured with fixed depth irradiation (~11.5% for both crystals). Lastly, we demonstrated how the Richardson-Lucy algorithm, an iterative, ML-based deconvolution technique, can be applied to the digitized waveforms to deconvolve the photodetector's single photoelectron response and produce waveforms with a faster rising edge. After deconvolution and applying DOI and time-walk corrections, we demonstrated a 13% improvement in coincidence timing resolution (from 290 to 254 ps) with the LFS crystal and an 8% improvement (323 to 297 ps) with the LYSO crystal.

Ecological studies on the breeding of Aedes aegypti and other mosquitos in shells of the giant African snail Achatina fulica

PubMed Central

Trpis, Milan

1973-01-01

The breeding of larvae of Aedes aegypti, Aedes simpsoni, and Eretmapodites quinquevittatus in empty shells of Achatina fulica was studied in the coastal zone of Dar es Salaam, Tanzania. The average density of shells was estimated to be 228 per ha. From 11 to 35% were positive for mosquito larvae. A. aegypti were found in 82-84% of positive shells; A. simpsoni in 8-13%. On Msasani peninsula, during the 3-month rainy season April—June 1970, the larval density of A. aegypti in shells was estimated at 1 100 per ha, that of A. simpsoni and E. quinquevittatus being estimated at 60 and 280 larvae per ha, respectively. Empty shells of A. fulica may contain up to 250 ml of water (average: 56.5 ml). The number of larvae per shell varies from 1 to 35 (average: 8.4) and it was estimated that, depending on the availability of food, and other factors, approximately 10 ml of water are required per larva. Viable eggs of A. aegypti were still to be found in 4% of the shells at the end of the dry season. PMID:4148745

Laparoscopic Choledochoduodenostomy.

PubMed

Cuendis-Velázquez, Adolfo; E Trejo-Ávila, Mario; Rosales-Castañeda, Enrique; Cárdenas-Lailson, Eduardo; E Rojano-Rodríguez, Martin; Romero-Loera, Sujey; A Sanjuan-Martínez, Carlos; Moreno-Portillo, Mucio

Today's options for biliary bypass procedures, for difficult choledocholithiasis, range from open surgery to laparo-endoscopic hybrid procedures. The aim of this study was to analyze the outcomes of patients with difficult choledocholithiasis treated with laparoscopic choledochoduodenostomy. We performed a prospective observational study from March 2011 to June 2016. We included patients with difficult common bile duct stones (recurrent or unresolved by ERCP) in which a biliary bypass procedure was required. We performed a laparoscopic bile duct exploration with choledochoduodenostomy and intraoperative cholangioscopy. A total of 19 patients were included. We found female predominance (78.9%), advanced mean age (72.4±12 years) and multiple comorbidities. Most patients with previous episodes of choledocholitiasis or cholangitis, mode 1 (min-max: 1-7). Mean common bile duct diameter 24.9±7mm. Mean operative time 218.5±74min, estimated blood loss 150 (30-600)mL, resume of oral intake 3.2±1 days, postoperative length of stay 4.9±2 days. We found a median of 18 (12-32) months of follow-up. All patients with normalization of liver enzymes during follow-up. One patient presented with sump syndrome and one patient died due to nosocomial pneumonia. Laparoscopic choledochoduodenostomy with intraoperative cholangioscopy seems to be safe and effective treatment for patients with difficult common bile duct stones no resolved by endoscopic procedures. This procedure is a good option for patients with advanced age and multiple comorbidities. We offer all the advantages of minimally invasive surgery to these patients. Copyright © 2017 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

Safety and feasibility of the robotic platform in the management of surgical sequelae of chronic pancreatitis.

PubMed

Hamad, Ahmad; Zenati, Mazen S; Nguyen, Trang K; Hogg, Melissa E; Zeh, Herbert J; Zureikat, Amer H

2018-02-01

The application of minimally invasive surgery to chronic pancreatitis (CP) procedures is uncommon. Our objective was to report the safety and feasibility of the robotic approach in the treatment of surgical sequelae of CP, and provide insights into the technique, tricks, and pitfalls associated with the application of robotics to this challenging disease entity. A retrospective review of a prospectively maintained database of patients undergoing robotic-assisted resections and/or drainage procedures for CP at the University of Pittsburgh between May 2009 and January 2017 was performed. A video of a robotic Frey procedure is also shown. Of 812 robotic pancreatic resections and reconstructions 39 were for CP indications. These included 11 total pancreatectomies [with and without auto islet transplantation], 8 Puestow procedures, 4 Frey procedures, 6 pancreaticoduodenectomies, and 10 distal pancreatectomies. Median age was 49, and 41% of the patients were female. The most common etiology for CP was idiopathic pancreatitis (n = 16, 46%). Median operative time was 324 min with a median estimated blood loss of 250 ml. None of the patients required conversion to laparotomy. A Clavien III-IV complication rate was experienced by 5 (13%) patients, including one reoperation. Excluding the eleven patients who underwent TP, rate of clinically relevant postoperative pancreatic fistula was 7% (Grade B = 2, Grade C = 0). No 30 or 90 day mortalities were recorded. The median length of hospital stay was 7 days. Use of the robotic platform is safe and feasible when tackling complex pancreatic resections for sequelae of chronic pancreatitis.

Optimization of the procedure for counting the eggs of Fasciola gigantica in bovine faeces.

PubMed

Suhardono; Roberts, J A; Copeman, D B

2006-07-01

This paper describes a method for counting eggs of F. gigantica in bovine faeces that optimizes the proportion of eggs recovered and the repeatability of estimates. The method uses 3 g of faeces suspended in 0.05% Tween 20. The suspension is passed through three 6 cm diameter sieves in tandem to remove fibrous debris, with respective apertures of 1 mm, 450 microm, and either 266 or 200 microm. The filtrate is allowed to sediment for 3 min in a conical flask; the sediment is recovered, then resuspended in 200 ml of 0.05% Tween 20 and allowed to sediment. After 3 min the sediment is washed in a sieve with an aperture of 53 microm, which retains the eggs. Eggs suspended in 15 ml of 1% methylene blue are counted using a dissecting microscope. Use of Tween 20 instead of water as the suspending agent for faeces gave a significant threefold increased the proportion of eggs recovered and reduced variability between repeated counts. This method is able to detect about one-third of the eggs present. It was concluded that the high proportion of F. gigantica eggs lost may be due to the presence of hydrophobic and covalent bonds on the eggs that bind them to debris, with which they are discarded.

Selection of process conditions by risk assessment for apple juice pasteurization by UV-heat treatments at moderate temperatures.

PubMed

Gayán, E; Torres, J A; Alvarez, I; Condón, S

2014-02-01

The effect of bactericidal UV-C treatments (254 nm) on Escherichia coli O157:H7 suspended in apple juice increased synergistically with temperature up to a threshold value. The optimum UV-C treatment temperature was 55 °C, yielding a 58.9% synergistic lethal effect. Under these treatment conditions, the UV-heat (UV-H55 °C) lethal variability achieving 5-log reductions had a logistic distribution (α = 37.92, β = 1.10). Using this distribution, UV-H55 °C doses to achieve the required juice safety goal with 95, 99, and 99.9% confidence were 41.17, 42.97, and 46.00 J/ml, respectively, i.e., doses higher than the 37.58 J/ml estimated by a deterministic procedure. The public health impact of these results is that the larger UV-H55 °C dose required for achieving 5-log reductions with 95, 99, and 99.9% confidence would reduce the probability of hemolytic uremic syndrome in children by 76.3, 88.6, and 96.9%, respectively. This study illustrates the importance of including the effect of data variability when selecting operational parameters for novel and conventional preservation processes to achieve high food safety standards with the desired confidence level.

Measurement and Structural Model Class Separation in Mixture CFA: ML/EM versus MCMC

ERIC Educational Resources Information Center

Depaoli, Sarah

2012-01-01

Parameter recovery was assessed within mixture confirmatory factor analysis across multiple estimator conditions under different simulated levels of mixture class separation. Mixture class separation was defined in the measurement model (through factor loadings) and the structural model (through factor variances). Maximum likelihood (ML) via the…

Single-sample 99mTc-diethylenetriamine penta-acetate plasma clearance in advanced renal failure by the mean sojourn time approach.

PubMed

Gref, Margareta C; Karp, Kjell H

2009-03-01

The single-sample Tc-diethylenetriamine penta-acetate (DTPA) clearance method by Christensen and Groth is recommended by the Radionuclides in Nephrourology Committee on Renal Clearance for use in adults with an estimated glomerular filtration rate (GFR) > or = 30 ml/min. The purpose of this study was to test a new Tc-DTPA single-sample low clearance formula for GFR lesser than 30 ml/min. Twenty-one adult patients (29 investigations) were included. Reference clearance was calculated with both Cr-EDTA and Tc-DTPA according to Brøchner-Mortensen with samples drawn between 3 and 24 h. Single-sample clearance was calculated from a 24 h sample using the low clearance formula(Equation is included in full-text article.) C(t) is the activity of the tracer in the plasma sample t minutes after the injection and Q0 is the injected amount. ECV is the extracellular volume in ml defined as the distribution volume of the tracer. ECV is estimated from the body surface area as ECV=8116.6xbody surface area-28.2. The mean difference between reference and Tc-DTPA single-sample clearance was -0.5 ml/min (SD 1.0 ml/min) for Tc-DTPA and -0.8 ml/min (SD 1.2 ml/min) for Cr-EDTA as reference clearance. In adult patients it is possible, even with GFR lesser than 30 ml/min, to get an accurate determination of Tc-DTPA plasma clearance from a single sample using the mean sojourn time approach. The blood sample should be obtained about 24 h after injection of the GFR tracer.

Population pharmacokinetics of epsilon-aminocaproic acid in infants undergoing craniofacial reconstruction surgery

PubMed Central

Stricker, P. A.; Zuppa, A. F.; Fiadjoe, J. E.; Maxwell, L. G.; Sussman, E. M.; Pruitt, E. Y.; Goebel, T. K.; Gastonguay, M. R.; Taylor, J. A.; Bartlett, S. P.; Schreiner, M. S.

2013-01-01

Background Understanding the clinical pharmacology of the antifibrinolytic epsilon-aminocaproic acid (EACA) is necessary for rational drug administration in children. The aim of this study is to determine the pharmacokinetics (PKs) of EACA in infants aged 6–24 months undergoing craniofacial reconstruction surgery. Methods Cohorts of six infants were enrolled sequentially to one of the three escalating loading dose–continuous i.v. infusion (CIVI) regimens: 25 mg kg−1, 10 mg kg−1 h−1; 50 mg kg−1, 20 mg kg−1 h−1; 100 mg kg−1, 40 mg kg−1 h−1. Plasma EACA concentrations were determined using a validated high-performance liquid chromatography-tandem mass spectrometry assay. A population non-linear mixed effects modelling approach was used to characterize EACA PKs. Results Population PK parameters of EACA were estimated using a two-compartment disposition model with weight expressed as an allometric covariate and an age effect. The typical patient in this study had an age of 38.71 weeks and a weight of 8.82 kg. PK parameters for this typical patient were: pre-/postoperative plasma drug clearance of 32 ml min−1 (3.6 ml kg−1 min−1), inter-compartmental clearance of 42.4 ml min−1 (4.8 ml min−1 kg−1), central volume of distribution of 1.27 litre (0.14 litre kg−1), and peripheral volume of distribution of 2.53 litre (0.29 litre kg−1). Intra-operative clearance and central volume of distribution were 89% and 80% of the pre-/postoperative value, respectively. Conclusions EACA clearance increased with weight and age. The dependence of clearance on body weight supports weight-based dosing. Based on this study, a loading dose of 100 mg kg−1 followed by a CIVI of 40 mg kg−1 h−1 is appropriate to maintain target plasma EACA concentrations in children aged 6–24 months undergoing these procedures. PMID:23353035

Population pharmacokinetics of epsilon-aminocaproic acid in infants undergoing craniofacial reconstruction surgery.

PubMed

Stricker, P A; Zuppa, A F; Fiadjoe, J E; Maxwell, L G; Sussman, E M; Pruitt, E Y; Goebel, T K; Gastonguay, M R; Taylor, J A; Bartlett, S P; Schreiner, M S

2013-05-01

Understanding the clinical pharmacology of the antifibrinolytic epsilon-aminocaproic acid (EACA) is necessary for rational drug administration in children. The aim of this study is to determine the pharmacokinetics (PKs) of EACA in infants aged 6-24 months undergoing craniofacial reconstruction surgery. Cohorts of six infants were enrolled sequentially to one of the three escalating loading dose-continuous i.v. infusion (CIVI) regimens: 25 mg kg(-1), 10 mg kg(-1) h(-1); 50 mg kg(-1), 20 mg kg(-1) h(-1); 100 mg kg(-1), 40 mg kg(-1) h(-1). Plasma EACA concentrations were determined using a validated high-performance liquid chromatography-tandem mass spectrometry assay. A population non-linear mixed effects modelling approach was used to characterize EACA PKs. Population PK parameters of EACA were estimated using a two-compartment disposition model with weight expressed as an allometric covariate and an age effect. The typical patient in this study had an age of 38.71 weeks and a weight of 8.82 kg. PK parameters for this typical patient were: pre-/postoperative plasma drug clearance of 32 ml min(-1) (3.6 ml kg(-1) min(-1)), inter-compartmental clearance of 42.4 ml min(-1) (4.8 ml min(-1) kg(-1)), central volume of distribution of 1.27 litre (0.14 litre kg(-1)), and peripheral volume of distribution of 2.53 litre (0.29 litre kg(-1)). Intra-operative clearance and central volume of distribution were 89% and 80% of the pre-/postoperative value, respectively. EACA clearance increased with weight and age. The dependence of clearance on body weight supports weight-based dosing. Based on this study, a loading dose of 100 mg kg(-1) followed by a CIVI of 40 mg kg(-1) h(-1) is appropriate to maintain target plasma EACA concentrations in children aged 6-24 months undergoing these procedures.

Aqueous penetration and biological activity of moxifloxacin 0.5% ophthalmic solution and gatifloxacin 0.3% solution in cataract surgery patients.

PubMed

Kim, Dianne H; Stark, Walter J; O'Brien, Terrence P; Dick, James D

2005-11-01

To measure the achievable perioperative aqueous concentration of the commercially available topically administered fourth generation fluoroquinolones, moxifloxacin 0.5% ophthalmic solution, and gatifloxacin 0.3% ophthalmic solution, and to correlate this concentration with the agents' biological efficacy in the aqueous humor of patients undergoing routine cataract surgery. Prospective, randomized, parallel, double-masked, clinical trial. Fifty patients undergoing cataract extraction. Patients (n = 25) were given perioperative topical moxifloxacin 0.5% or topical gatifloxacin 0.3% (n = 25). One drop of antibiotic was administered every 10 minutes for 4 doses beginning 1 hour prior to surgery. Aqueous humor was sampled via paracentesis and antibiotic concentrations were determined using validated high performance liquid chromatography (HPLC) procedures. Dilution analyses were performed to determine the biological efficacy of the agents in the aqueous against Staphylococcus epidermidis, the most common cause of postcataract endophthalmitis. Aqueous humor antibiotic concentrations were measured using HPLC and microdilution bioassay techniques. Biological activity was measured as minimal inhibitory dilution and minimal bactericidal dilution. Aqueous humor concentrations for moxifloxacin via HPLC analysis were 1.80 (+/-1.21) microg/ml, whereas those for gatifloxacin were 0.48 (+/-0.34) microg/ml. This 3.8-fold difference in aqueous humor antibiotic concentrations was statistically significant (P = 0.00003). Similarly, the biological dilution analysis of the aqueous humor samples showed that moxifloxacin attained an estimated activity of 2.1 microg/ml, whereas the gatifloxacin activity was approximately 0.4 mug/ml, which represented a 4.9-fold difference. This study demonstrated that after topically administered perioperative antibiotics with cataract surgery, moxifloxacin 0.5% ophthalmic solution achieved a statistically significantly higher concentration in aqueous humor compared with gatifloxacin (P = 0.00003). Results from the broth dilution analysis showed that moxifloxacin 0.5% was biologically more active against S. epidermidis than gatifloxacin 0.3% in aqueous humor after topical application. There were no adverse events reported, and incision wounds healed quickly and as expected.

Toward Current Standards of Donor Right Hepatectomy for Adult-to-Adult Live Donor Liver Transplantation Through the Experience of 200 Cases

PubMed Central

Chan, See Ching; Fan, Sheung Tat; Lo, Chung Mau; Liu, Chi Leung; Wong, John

2007-01-01

Objective: To define the current standards of donor right hepatectomy, including the middle hepatic vein for adult-to-adult live donor liver transplantation. Summary Background Data: Donor morbidity and mortality are inevitable given the ultra-major nature of the donor operation. Results from a matured center could define the true impact of this donor procedure most accurately. Patients and Methods: From May 9, 1996 to April 13, 2005, 200 consecutive donors underwent donor right hepatectomy at the University of Hong Kong Medical Center. All right liver grafts except one included the middle hepatic vein. Donor characteristics, operation time, blood loss, hospital stay, laboratory results, and complications graded by Clavien's classification divided into four eras (each consecutive 50 cases) were compared. Results: Donor characteristics of the four eras were generally comparable. Operative outcomes improved progressively through the four eras. From era 1 to era 4, operation time decreased from 598 minutes (range, 378–932 minutes) to 391 minutes (range, 304–635 minutes). Blood loss also decreased from 500 mL (200–1600 mL) of era 1 to 251 mL (range, 95–595 mL) of era 4. Overall complication rate was 20.5% (41 of 200). Complications rates from eras 1 to 4 were 34%, 16%, 16%, and 16%, respectively. The most common complications were of grade I (24 of 41, 58.5%). A late donor death occurred in era 4 from the development of a duodenocaval fistula 10 weeks postoperation, giving a donor mortality of 0.5% (1 of 200). Conclusions: This study validated the estimated morbidity and mortality of donor right hepatectomy of 20% and 0.5%, respectively. The data provide reference for counseling potential donors and setting the standards of donor right hepatectomy in the current era. PMID:17197973

Association of preoperative plasma fibrinogen level with postoperative bleeding after on-pump coronary bypass surgery: does plasma fibrinogen level affect the amount of postoperative bleeding?

PubMed

Alagha, Sameh; Songur, Murat; Avci, Tugba; Vural, Kerem; Kaplan, Sadi

2018-05-15

Our primary aim was to investigate the association between the preoperative concentration of plasma fibrinogen and the volume of postoperative bleeding. Our secondary aim was to identify whether there is a possible correlation between the patients' different characteristics and haemostatic laboratory variables and the postoperative amount of bleeding after on-pump coronary artery bypass grafting procedures. A total of 550 adult patients undergoing isolated coronary artery bypass grafting on cardiopulmonary bypass in our hospital were enrolled and investigated retrospectively. The total amount of chest tube drainage within the first 24 postoperative hours or until the patient was re-explored for bleeding was assessed. Excessive bleeding was defined as more than 500 ml drainage in the first 24 h. The patients were divided into 2 groups: Group 1: the patients who bled ≤500 ml in the first 24 h and Group 2: the patients who bled >500 ml in the first 24 h. A preoperative fibrinogen threshold associated with excessive bleeding was investigated by receiver operating characteristic curve analyses, revealing a calculated cutoff value of 3.1 g/l. Risk factors for increased bleeding were analysed by a logistic regression model that revealed male gender (P < 0.001), body mass index ≤28.3 kg/m2 (P < 0.001), platelet count ≤233 × 103/µl (P < 0.001), estimated glomerular filtration rate ≤90.8 ml/min (P < 0.001) and fibrinogen ≤3.1 g/l (P = 0.01) as significant predictors. A preoperative plasma fibrinogen concentration <3.1 g/l was associated with increased risk of excessive bleeding in patients undergoing on-pump coronary artery bypass grafting. The amount of postoperative blood loss can be roughly predicted with simple preoperative blood tests.

Solution of rocks and refractory minerals by acids at high temperatures and pressures. Determination of silica after decomposition with hydrofluoric acid

USGS Publications Warehouse

May, I.; Rowe, J.J.

1965-01-01

A modified Morey bomb was designed which contains a removable nichromecased 3.5-ml platinium crucible. This bomb is particularly useful for decompositions of refractory samples for micro- and semimicro-analysis. Temperatures of 400-450?? and pressures estimated as great as 6000 p.s.i. were maintained in the bomb for periods as long as 24 h. Complete decompositions of rocks, garnet, beryl, chrysoberyl, phenacite, sapphirine, and kyanite were obtained with hydrofluoric acid or a mixture of hydrofluoric and sulfuric acids; the decomposition of chrome refractory was made with hydrochloric acid. Aluminum-rich samples formed difficultly soluble aluminum fluoride precipitates. Because no volatilization losses occur, silica can be determined on sample solutions by a molybdenum-blue procedure using aluminum(III) to complex interfering fluoride. ?? 1965.

Process Design and Cost Estimating Algorithms for the Computer Assisted Procedure for Design and Evaluation of Wastewater Treatment Systems (CAPDET).

DTIC Science & Technology

1982-01-01

mg/l. 2.1.9.1.3.3 Nitrogen, I Mg 1. 2.1.9.1.3.4 Phosphorus (total and soluble), ag/l. 2.1.9.1.3.5 Oils and greases, mg/l. 2.1.9.1.3.6 Heavy metals , mg...greases, mg/I. 2.1.10.1.3.6 Heavy metals , m/l. 2.1.10.1.3.7 Toxic or special characteristics (e.g., phenols), mg/I. 2.1.10.1.3.8 Temperature, OF or °C...1 mg/l. 2.1.11.1.3.4 Phosphorus (total and soluble), mg/I. 2.1.11.1.3.5 Oils and greases, mgl. 2.1.11.1.3.6 Heavy metals , mg/l. 2.1.11.1.3.7 Toxic or

Minilaparotomy with a gasless laparoscopic-assisted procedure by abdominal wall lifting for ileorectal anastomosis in patients with slow transit constipation.

PubMed

Tomita, Ryouichi; Fujisak, Shigeru

2009-01-01

Total colectomy with ileorectal anastomosis (IRA) is the most widely adopted procedure. The aim of this study was to introduce a minimally invasive procedure, i.e., minilaparotomy with laparoscopic-assisted procedure, by abdominal wall lifting for IRA in patients with slow transit constipation (STC). Six STC patients (6 women, aged 40-69 years, mean age 56.3 years) underwent minilaparotomy with gasless laparoscopic-assisted approach by abdominal wall lifting for IRA. The present procedure involved a 7-cm lower abdominal median incision made at the beginning of the operation. 12 mm ports were also placed in the right and left upper abdominal quadrant positions. The upper abdominal wall was lifted by a subcutaneous Kirshner wire. The small wound was pulled upward and/or laterally by retractors (abdominal lifting) and conventional surgical instruments were used through the wound. Occasionally laparoscopic assistance was employed. The terminal ileum with total colon was brought out through the small wound and transected, approximately 5 cm from the ileocecal valve. The colon was also resected at the level of promontrium. Then, IRA was performed in the instruments. The total surgical time was 197.7 +/- 33.9 min and the mean estimated blood loss was 176.8 +/- 42.2 ml. There was no surgical mortality. Post-operative hospitalization was 8.1 +/- 2.1 days. Six months after surgery, they defecated 1.8 +/- 2.1 times daily, have no abdominal distension, pain, and incontinence. The patients also take no laxatives. All subjects were satisfied with this procedure. Minilaparotomy with gasless laparoscopic-assisted IRA by abdominal wall lifting could be a safe and efficient technique in the treatment of STC.

Estimation of calcium and magnesium in serum and urine by atomic absorption spectrophotometry

PubMed Central

Thin, Christian G.; Thomson, Patricia A.

1967-01-01

A method has been described for the estimation of calcium and magnesium in serum and urine using atomic absorption spectrophotometry. The precision and accuracy of the techniques have been determined and were found to be acceptable. The range of values for calcium and magnesium in the sera of normal adults was found to be: serum calcium (corrected to a specific gravity of 1·026) 8·38-10·08 mg. per 100 ml.; serum magnesium 1·83-2·43 mg. per 100 ml. PMID:5602562

Randomized Trial of Studer Pouch versus T-Pouch Orthotopic Ileal Neobladder in Patients with Bladder Cancer.

PubMed

Skinner, Eila C; Fairey, Adrian S; Groshen, Susan; Daneshmand, Siamak; Cai, Jie; Miranda, Gus; Skinner, Donald G

2015-08-01

The need to prevent reflux in the construction of an orthotopic ileal neobladder is controversial. We designed the USC-STAR trial to determine whether the T-pouch neobladder that included an antireflux mechanism was superior to the Studer pouch in patients with bladder cancer undergoing radical cystectomy. This single center, randomized, controlled trial recruited patients with clinically nonmetastatic bladder cancer scheduled to undergo radical cystectomy with neobladder. Eligible patients were randomly assigned to undergo T-pouch or Studer ileal orthotopic neobladder. Treatment assignment was not masked. The primary end point was change in renal function from baseline to 3 years. The CKD-EPI (Chronic Kidney Disease Epidemiology Collaboration) equation was used to calculate the estimated glomerular filtration rate. Between February 2002 and November 2009, 237 patients were randomly assigned to T-pouch ileal orthotopic neobladder and 247 to Studer ileal orthotopic neobladder. Baseline characteristics did not differ between the groups. Between baseline and 3 years the estimated glomerular filtration rate decreased by 6.4 ml/minute/1.73 m(2) in the Studer group and 6.6 ml/minute/1.73 m(2) in the T-pouch group (p=0.35). Multivariable analysis showed that type of ileal orthotopic neobladder was not independently associated with 3-year renal function (p=0.63). However, baseline estimated glomerular filtration rate, age and urinary tract obstruction were independently associated with 3-year decline in renal function. Cumulative risk of urinary tract infection and overall late complications were not different between the groups, but the T-pouch was associated with an increased risk of secondary diversion related surgeries. T-pouch ileal orthotopic neobladder with an antireflux mechanism did not prevent a moderate reduction in renal function observed at 3 years compared to the Studer pouch, but did result in an increase in diversion related secondary surgical procedures. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

A statistical method for estimating rates of soil development and ages of geologic deposits: A design for soil-chronosequence studies

USGS Publications Warehouse

Switzer, P.; Harden, J.W.; Mark, R.K.

1988-01-01

A statistical method for estimating rates of soil development in a given region based on calibration from a series of dated soils is used to estimate ages of soils in the same region that are not dated directly. The method is designed specifically to account for sampling procedures and uncertainties that are inherent in soil studies. Soil variation and measurement error, uncertainties in calibration dates and their relation to the age of the soil, and the limited number of dated soils are all considered. Maximum likelihood (ML) is employed to estimate a parametric linear calibration curve, relating soil development to time or age on suitably transformed scales. Soil variation on a geomorphic surface of a certain age is characterized by replicate sampling of soils on each surface; such variation is assumed to have a Gaussian distribution. The age of a geomorphic surface is described by older and younger bounds. This technique allows age uncertainty to be characterized by either a Gaussian distribution or by a triangular distribution using minimum, best-estimate, and maximum ages. The calibration curve is taken to be linear after suitable (in certain cases logarithmic) transformations, if required, of the soil parameter and age variables. Soil variability, measurement error, and departures from linearity are described in a combined fashion using Gaussian distributions with variances particular to each sampled geomorphic surface and the number of sample replicates. Uncertainty in age of a geomorphic surface used for calibration is described using three parameters by one of two methods. In the first method, upper and lower ages are specified together with a coverage probability; this specification is converted to a Gaussian distribution with the appropriate mean and variance. In the second method, "absolute" older and younger ages are specified together with a most probable age; this specification is converted to an asymmetric triangular distribution with mode at the most probable age. The statistical variability of the ML-estimated calibration curve is assessed by a Monte Carlo method in which simulated data sets repeatedly are drawn from the distributional specification; calibration parameters are reestimated for each such simulation in order to assess their statistical variability. Several examples are used for illustration. The age of undated soils in a related setting may be estimated from the soil data using the fitted calibration curve. A second simulation to assess age estimate variability is described and applied to the examples. ?? 1988 International Association for Mathematical Geology.

Two-step liquid phase microextraction combined with capillary electrophoresis: a new approach to simultaneous determination of basic and zwitterionic compounds.

PubMed

Nojavan, Saeed; Moharami, Arezoo; Fakhari, Ali Reza

2012-08-01

In this work, two-step hollow fiber-based liquid-phase microextraction procedure was evaluated for extraction of the zwitterionic cetirizine (CTZ) and basic hydroxyzine (HZ) in human plasma. In the first step of extraction, the pH of sample was adjusted at 5.0 in order to promote liquid-phase microextraction of the zwitterionic CTZ. In the second step, the pH of sample was increased up to 11.0 for extraction of basic HZ. In this procedure, the extraction times for the first and the second steps were 30 and 20 min, respectively. Owing to the high ratio between the volumes of donor phase and acceptor phase, CTZ and HZ were enriched by factors of 280 and 355, respectively. The linearity of the analytical method was investigated for both compounds in the range of 10-500 ng mL(-1) (R(2) > 0.999). Limit of quantification (S/N = 10) for CTZ and HZ was 10 ng mL(-1) , while the limit of detection was 3 ng mL(-1) for both compounds at a signal to noise ratio of 3:1. Intraday and interday relative standard deviations (RSDs, n = 6) were in the range of 6.5-16.2%. This procedure enabled CTZ and HZ to be analyzed simultaneously by capillary electrophoresis. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Gastric residual volume (GRV) and gastric contents measurement by refractometry.

PubMed

Chang, Wei-Kuo; McClave, Stephen A; Hsieh, Chung-Bao; Chao, You-Chen

2007-01-01

Traditional use of gastric residual volumes (GRVs), obtained by aspiration from a nasogastric tube, is inaccurate and cannot differentiate components of the gastric contents (gastric secretion vs delivered formula). The use of refractometry and 3 mathematical equations has been proposed as a method to calculate the formula concentration, GRV, and formula volume. In this paper, we have validated these mathematical equations so that they can be implemented in clinical practice. Each of 16 patients receiving a nasogastric tube had 50 mL of water followed by 100 mL of dietary formula (Osmolite HN, Abbott Laboratories, Columbus, OH) infused into the stomach. After mixing, gastric content was aspirated for the first Brix value (BV) measurement by refractometry. Then, 50 mL of water was infused into the stomach and a second BV was measured. The procedure of infusion of dietary formula (100 mL) and then water (50 mL) was repeated and followed by subsequent BV measurement. The same procedure was performed in an in vitro experiment. Formula concentration, GRV, and formula volume were calculated from the derived mathematical equations. The formula concentrations, GRVs, and formula volumes calculated by using refractometry and the mathematical equations were close to the true values obtained from both in vivo and in vitro validation experiments. Using this method, measurement of the BV of gastric contents is simple, reproducible, and inexpensive. Refractometry and the derived mathematical equations may be used to measure formula concentration, GRV, and formula volume, and also to serve as a tool for monitoring the gastric contents of patients receiving nasogastric feeding.

The Outcome of Primary Subglandular Breast Augmentation Using Tumescent Local Anesthesia.

PubMed

Rusciani, Antonio; Pietramaggiori, Giorgio; Troccola, Antonietta; Santoprete, Stefano; Rotondo, Antonio; Curinga, Giuseppe

2016-01-01

Tumescent local anesthesia (TLA) technique to obtain regional anesthesia and vasoconstriction of the skin and subcutaneous tissues is routinely adopted for several plastic surgery procedures. Here, we describe the use of TLA in primary subglandular breast augmentation. This series evaluates advantages and disadvantages of TLA in elective augmentation breast surgery as well as patients' response to this procedure. Between December 2008 and November 2011, 150 patients underwent bilateral primary subglandular breast augmentation under TLA and conscious sedation in the presence of a board-certified anesthesiologist. Midazolam 0.05 mg/kg IV and ranitidine 100 mg IV were given as premedication. Tumescent local anesthesia was composed of 25 mL of lidocaine 2%, 8 mEq of sodium bicarbonate, and 1 mL of epinephrine (1 mg/1 mL) in 1000 mL of 0.9% NS. The solution was delivered between the pectoral fascia and the mammary gland via a spinal needle. After infiltration, 45 minutes were allowed before surgery for local anesthetic effects to take place. The mean age of the patients was 34.3 years. The average amount of tumescent solution infiltrated was 1150 mL, with a maximal dose of 17 mg/kg of lidocaine used. Operating time was 45 minutes and recovery room time averaged 125 minutes. Minor complications were found in a total of 9 (5.3%) patients, with no main surgery-related complications such as hematoma or seroma formation. Breast augmentation under TLA and conscious sedation proved to be safe in the presence of a board-certified anesthesiologist and when performed with meticulous surgical technique.

An Algorithm for Efficient Maximum Likelihood Estimation and Confidence Interval Determination in Nonlinear Estimation Problems

NASA Technical Reports Server (NTRS)

Murphy, Patrick Charles

1985-01-01

An algorithm for maximum likelihood (ML) estimation is developed with an efficient method for approximating the sensitivities. The algorithm was developed for airplane parameter estimation problems but is well suited for most nonlinear, multivariable, dynamic systems. The ML algorithm relies on a new optimization method referred to as a modified Newton-Raphson with estimated sensitivities (MNRES). MNRES determines sensitivities by using slope information from local surface approximations of each output variable in parameter space. The fitted surface allows sensitivity information to be updated at each iteration with a significant reduction in computational effort. MNRES determines the sensitivities with less computational effort than using either a finite-difference method or integrating the analytically determined sensitivity equations. MNRES eliminates the need to derive sensitivity equations for each new model, thus eliminating algorithm reformulation with each new model and providing flexibility to use model equations in any format that is convenient. A random search technique for determining the confidence limits of ML parameter estimates is applied to nonlinear estimation problems for airplanes. The confidence intervals obtained by the search are compared with Cramer-Rao (CR) bounds at the same confidence level. It is observed that the degree of nonlinearity in the estimation problem is an important factor in the relationship between CR bounds and the error bounds determined by the search technique. The CR bounds were found to be close to the bounds determined by the search when the degree of nonlinearity was small. Beale's measure of nonlinearity is developed in this study for airplane identification problems; it is used to empirically correct confidence levels for the parameter confidence limits. The primary utility of the measure, however, was found to be in predicting the degree of agreement between Cramer-Rao bounds and search estimates.

The "covariation method" for estimating the parameters of the standard Dynamic Energy Budget model II: Properties and preliminary patterns

NASA Astrophysics Data System (ADS)

Lika, Konstadia; Kearney, Michael R.; Kooijman, Sebastiaan A. L. M.

2011-11-01

The covariation method for estimating the parameters of the standard Dynamic Energy Budget (DEB) model provides a single-step method of accessing all the core DEB parameters from commonly available empirical data. In this study, we assess the robustness of this parameter estimation procedure and analyse the role of pseudo-data using elasticity coefficients. In particular, we compare the performance of Maximum Likelihood (ML) vs. Weighted Least Squares (WLS) approaches and find that the two approaches tend to converge in performance as the number of uni-variate data sets increases, but that WLS is more robust when data sets comprise single points (zero-variate data). The efficiency of the approach is shown to be high, and the prior parameter estimates (pseudo-data) have very little influence if the real data contain information about the parameter values. For instance, the effects of the pseudo-value for the allocation fraction κ is reduced when there is information for both growth and reproduction, that for the energy conductance is reduced when information on age at birth and puberty is given, and the effects of the pseudo-value for the maturity maintenance rate coefficient are insignificant. The estimation of some parameters (e.g., the zoom factor and the shape coefficient) requires little information, while that of others (e.g., maturity maintenance rate, puberty threshold and reproduction efficiency) require data at several food levels. The generality of the standard DEB model, in combination with the estimation of all of its parameters, allows comparison of species on the basis of parameter values. We discuss a number of preliminary patterns emerging from the present collection of parameter estimates across a wide variety of taxa. We make the observation that the estimated value of the fraction κ of mobilised reserve that is allocated to soma is far away from the value that maximises reproduction. We recognise this as the reason why two very different parameter sets must exist that fit most data set reasonably well, and give arguments why, in most cases, the set with the large value of κ should be preferred. The continued development of a parameter database through the estimation procedures described here will provide a strong basis for understanding evolutionary patterns in metabolic organisation across the diversity of life.

Performance of the Cockcroft-Gault and MDRD equations in adult Nigerians with chronic kidney disease.

PubMed

Agaba, Emmanuel I; Wigwe, Chinyere M; Agaba, Patricia A; Tzamaloukas, Antonios H

2009-01-01

Estimation of the glomerular filtration rate (GFR) is required in the assessment of patients with chronic kidney disease (CKD) in order to provide information regarding the functional status of the kidneys. Current guidelines advocate the use of prediction equations, such as the Cockcroft-Gault (CG) formula and the Modification of Diet in Renal Disease (MDRD) study-derived equations, over clearance of endogenous creatinine (Ccr) in achieving this aim. We were interested in knowing the accuracy of these equations in predicting the GFR in adult Nigerians with CKD. We conducted a review of records of patients who were evaluated for CKD at the Nephrology Clinic of the Jos University Teaching Hospital between 2001 and 2003. We compared the CG and MDRD equations against the Ccr in predicting the GFR in 130 patients (88 males and 42 females) with CKD. The means +/- standard deviation (SD) for the measured and predicted GFR by the CG and MDRD equations were similar (17.6 +/- 25.8 ml/min, 19.9 +/- 24.0 ml/min and 21.5 +/- 28.2 ml/min, respectively; analysis of variance [ANOVA], F = 0.68, P = 0.5). The mean difference between CG and Ccr was -2.2 +/- 14.8 ml/min, with discordance at Ccr values >25 ml/min. The mean difference between MDRD and Ccr was -3.9 +/- 18.1 ml/min, with discordance at Ccr values >40 ml/min. The CG and MDRD equations provide reliable alternatives to measured Ccr in the estimation of the GFR in Nigerian patients with CKD.

Frey procedure for chronic pancreatitis in children: A single center experience.

PubMed

Ray, Sukanta; Sanyal, Sumit; Ghatak, Supriyo; Khamrui, Sujan; Biswas, Jayanta; Saha, Suman; Mandal, Tuhin Subhra; Chattopadhyay, Gautam

2015-11-01

There is paucity of literature regarding the Frey procedure for children with chronic pancreatitis. The purpose of this study is to present our experience with the Frey procedure in children. This is an observational retrospective review study. All children, who underwent a Frey procedure between August 2007 and May 2014 in the Department of Surgical Gastroenterology, Institute of Postgraduate Medical Education and Research, Kolkata, India were included in this study. Twenty four children were included in our study. There were 13 girls and 11 boys. Mean age at operation was 13.95years (range, 4 to 18years). Mean duration between the diagnosis of chronic pancreatitis and surgery was 4.41years (range, 1 to 14years). Frey procedure was performed after failure of medical or endoscopic therapy. Mean duration of operation and blood loss were 215minutes (range, 150-300minutes) and 177ml (range, 50 to 500ml) respectively. Average postoperative hospital stay was 8days (range, 5 to 16days). Five patients (21%) developed postoperative complications. There was no in hospital mortality and no patient required reoperation for postoperative complications. More than a median follow-up of 29months (range, 3-78months), 91% of the patients remained pain free. Frey procedure is safe and feasible in children with acceptable perioperative complications and good short-term pain control. Copyright © 2015 Elsevier Inc. All rights reserved.

Validation protocol of analytical procedures for quantification of drugs in polymeric systems for parenteral administration: dexamethasone phosphate disodium microparticles.

PubMed

Martín-Sabroso, Cristina; Tavares-Fernandes, Daniel Filipe; Espada-García, Juan Ignacio; Torres-Suárez, Ana Isabel

2013-12-15

In this work a protocol to validate analytical procedures for the quantification of drug substances formulated in polymeric systems that comprise both drug entrapped into the polymeric matrix (assay:content test) and drug released from the systems (assay:dissolution test) is developed. This protocol is applied to the validation two isocratic HPLC analytical procedures for the analysis of dexamethasone phosphate disodium microparticles for parenteral administration. Preparation of authentic samples and artificially "spiked" and "unspiked" samples is described. Specificity (ability to quantify dexamethasone phosphate disodium in presence of constituents of the dissolution medium and other microparticle constituents), linearity, accuracy and precision are evaluated, in the range from 10 to 50 μg mL(-1) in the assay:content test procedure and from 0.25 to 10 μg mL(-1) in the assay:dissolution test procedure. The robustness of the analytical method to extract drug from microparticles is also assessed. The validation protocol developed allows us to conclude that both analytical methods are suitable for their intended purpose, but the lack of proportionality of the assay:dissolution analytical method should be taken into account. The validation protocol designed in this work could be applied to the validation of any analytical procedure for the quantification of drugs formulated in controlled release polymeric microparticles. Copyright © 2013 Elsevier B.V. All rights reserved.

Determination of vigabatrin in plasma by reversed-phase high-performance liquid chromatography.

PubMed

Tsanaclis, L M; Wicks, J; Williams, J; Richens, A

1991-05-01

A method is described for the determination of vigabatrin in 50 microliters of plasma by isocratic high-performance liquid chromatography using fluorescence detection. The procedure involves protein precipitation with methanol followed by precolumn derivatisation with o-phthaldialdehyde reagent. Separation of the derivatised vigabatrin was achieved on a Microsorb C18 column using a mobile phase of 10 mM orthophosphoric acid:acetonitrile:methanol (6:3:1) at a flow rate of 2.0 ml/min. Assay time is 15 min and chromatograms show no interference from commonly coadministered anticonvulsant drugs. The total analytical error within the range of 0.85-85 micrograms/ml was found to be 7.6% with the within-replicates error of 2.76%. The minimum detection limit was 0.08 micrograms/ml and the minimum quantitation limit was 0.54 micrograms/ml.

Estimation of contrast agent bolus arrival delays for improved reproducibility of liver DCE MRI

NASA Astrophysics Data System (ADS)

Chouhan, Manil D.; Bainbridge, Alan; Atkinson, David; Punwani, Shonit; Mookerjee, Rajeshwar P.; Lythgoe, Mark F.; Taylor, Stuart A.

2016-10-01

Delays between contrast agent (CA) arrival at the site of vascular input function (VIF) sampling and the tissue of interest affect dynamic contrast enhanced (DCE) MRI pharmacokinetic modelling. We investigate effects of altering VIF CA bolus arrival delays on liver DCE MRI perfusion parameters, propose an alternative approach to estimating delays and evaluate reproducibility. Thirteen healthy volunteers (28.7  ±  1.9 years, seven males) underwent liver DCE MRI using dual-input single compartment modelling, with reproducibility (n  =  9) measured at 7 days. Effects of VIF CA bolus arrival delays were assessed for arterial and portal venous input functions. Delays were pre-estimated using linear regression, with restricted free modelling around the pre-estimated delay. Perfusion parameters and 7 days reproducibility were compared using this method, freely modelled delays and no delays using one-way ANOVA. Reproducibility was assessed using Bland-Altman analysis of agreement. Maximum percent change relative to parameters obtained using zero delays, were  -31% for portal venous (PV) perfusion, +43% for total liver blood flow (TLBF), +3247% for hepatic arterial (HA) fraction, +150% for mean transit time and  -10% for distribution volume. Differences were demonstrated between the 3 methods for PV perfusion (p  =  0.0085) and HA fraction (p  <  0.0001), but not other parameters. Improved mean differences and Bland-Altman 95% Limits-of-Agreement for reproducibility of PV perfusion (9.3 ml/min/100 g, ±506.1 ml/min/100 g) and TLBF (43.8 ml/min/100 g, ±586.7 ml/min/100 g) were demonstrated using pre-estimated delays with constrained free modelling. CA bolus arrival delays cause profound differences in liver DCE MRI quantification. Pre-estimation of delays with constrained free modelling improved 7 days reproducibility of perfusion parameters in volunteers.

Re-assessing accumulated oxygen deficit in middle-distance runners.

PubMed

Bickham, D; Le Rossignol, P; Gibbons, C; Russell, A P

2002-12-01

The purpose of this study was to re-assess the accumulated oxygen deficit (AOD), incorporating recent methodological improvements i.e., 4 min submaximal tests spread above and below the lactate threshold (LT). We Investigated the Influence of the VO2 -speed regression, on the precision of the estimated total energy demand and AOD. utilising different numbers of regression points and including measurement errors. Seven trained middle-distance runners (mean +/- SD age: 25.3 +/- 5.4y, mass: 73.7 +/- 4.3kg. VO2max 64.4 +/- 6.1 mL x kg(-1) x min(-1)) completed a VO2max, LT, 10 x 4 min exercise tests (above and below LT) and high-intensity exhaustive tests. The VO2 -speed regression was developed using 10 submaximal points and a forced y-intercept value. The average precision (measured as the width of 95% confidence Interval) for the estimated total energy demand using this regression was 7.8mL O2 Eq x kg(-1) x min(-1). There was a two-fold decrease in precision of estimated total energy demand with the Inclusion of measurement errors from the metabolic system. The mean AOD value was 43.3 mL O2 Eq x kg(-1) (upper and lower 95% CI 32.1 and 54.5mL o2 Eq x kg(-1) respectively). Converting the 95% CI for estimated total energy demand to AOD or including maximum possible measurement errors amplified the error associated with the estimated total energy demand. No significant difference in AOD variables were found, using 10,4 or 2 regression points with a forced y-intercept. For practical purposes we recommend the use of 4 submaximal values with a y-intercept. Using 95% CIs and calculating error highlighted possible error in estimating AOD. Without accurate data collection, increased variability could decrease the accuracy of the AOD as shown by a 95% CI of the AOD.

The subdural evacuation port system: outcomes from a single institution experience and predictors of success.

PubMed

Neal, Matthew T; Hsu, Wesley; Urban, Jillian E; Angelo, Nicole M; Sweasey, Thomas A; Branch, Charles L

2013-06-01

Numerous surgical options for treatment of chronic subdural hematomas (cSDH) exist. Several reports have examined the Subdural Evacuating Port System (SEPS), a variation of the twist drill craniotomy (TDC) technique. Although high success rates have been reported, a significant portion of patients treated with SEPS fail and require additional procedures. This report examines the largest single institution experience with the SEPS and explores patient and imaging characteristics associated with successful procedures. A retrospective chart review was performed to identify all patients who have undergone SEPS drainage of cSDH. Demographic and radiographic characteristics were evaluated. Demographic data included patient's age, sex, presenting symptoms, pre-procedural GCS score, and use of anticoagulation or antiplatelet agents. The volume of drainage per procedure and radiographic data including laterality, density, and maximal diameter of the collection, presence of septations, midline shift, resolution of the collection 3 weeks post procedure, and measurements to assess atrophy were collected. Total length of stay and time in the intensive care unit was also recorded. Results were classified as a success or failure based on the need for additional procedures including craniotomy or burr hole craniotomy in the operating room. Patients treated with two SEPS procedures during the same hospitalization and no other procedures were included in the success group for statistical analyses. 171 subdural collections were treated in 159 patients (147 unilateral and 12 bilateral). One hundred thirty three collections (77.8%) were successfully drained. In a comparison of the success and failure groups, there were no statistically significant differences (p<0.05) in the patients' mean age, sex, presenting Glasgow Coma Scale score, coagulation profile, presenting symptoms (except altered mental status and language disturbance), subdural diameter or laterality, midline shift, presence of atrophy, density of most acute portion, or time in hospital. In the success group, there was a shorter mean stay in the intensive care unit (S: 4.1±4.5 days vs F: 5.4±4.6 days; p=0.03) and a larger output drained (S: 131.1±71.2ml vs F: 99.0±84.2ml; p=0.04). Success was less likely with mixed density collections (S: 38.2% vs F: 64.3%; p=0.02) and with collections containing greater than 2 intrahematomal septations (S: 17.1% vs F: 40.7%; p=0.007). In successful cases, mean volumes for collections prior to SEPS, immediately after SEPS, and on delayed scans (≥30 days since SEPS placement) the respective volumes were 83.1±35.1ml, 41.5±23.2ml, and 37.9±26.5ml. Both post-SEPS volumes were less than the pre-SEPS volume (p<0.0001). 76.0% of patients with delayed scans had complete resolution of cSDH or minimal residual cSDH with no local mass effect on the most recent imaging. The mean period of follow-up imaging was 95.6±196.2 days. Only one patient in our series required an emergent craniotomy following immediate complications from SEPS placement. The SEPS is an effective, safe, and durable treatment for cSDH. Although we consider the SEPS a first-line treatment for the majority of patients with cSDH, management of cSDH must be tailored to each patient. In mixed density collections with large proportions of acute hemorrhage and in collections with numerous intrahematomal septations, alternative surgical techniques should be considered as first-line therapies. Copyright © 2012 Elsevier B.V. All rights reserved.

Get Cracking.

ERIC Educational Resources Information Center

Croll, Doreen A.

1986-01-01

Presents a diversity of concrete experiences that can be used with eggs for young elementary age students. Includes procedures and material list for several activities that are hands-on and interdisciplinary in nature. (ML)

Gallium scan

MedlinePlus

... material called gallium and is a type of nuclear medicine exam. A related test is gallium scan ... Brown ML, Forstrom LA, et al. Society of nuclear medicine procedure guideline for gallium scintigraphy in inflammation. ...

[Studies for analyzing the prohibited ingredients such as acetohexamide in cosmetics].

PubMed

Tokunaga, Hiroshi; Uchino, Tadashi

2005-01-01

Acetohexamide (AH) is nominated as the prohibited ingredients in cosmetics in Japanese Pharmaceutical Affairs Act. So the analytical method for AH was investigated by HPLC. The lotion or milky lotion of 0.5g was put into a 10-ml volumetric flask. After adding 1.0ml of AH solution at 50 microg/ml into the volumetric flask, the mixture was made up to 10ml with methanol as the testing solution. Creams were procedured as follows; 0.5 g of cream was put into a 10-ml volumetric flask. After adding 1.0ml of tetrahydrofuran into the volumetric flask, the mixture was stirred for several minutes and the ingredients of the creams were dissolved. After adding 1.0ml of AH solution at 50 microg/ml into the volumetric flask, the mixture was made up to 10ml with methanol. One milliliter of the mixture including AH at 5 microg/ml was exactly put into a test tube with a cap and then 1 ml of water and 1 ml of hexane were added. After shaking vigorously, stand for several minutes. After centrifuging, the hexane layer was eliminated and the residual mixture was used as the test solution. The testing solution of 20 microl was analyzed by HPLC using the ODS column (CAPCELL PAK C18 column, 4.6 x 250mm), the mixture of acetonitrile and 50 mmol/l phosphate buffer(pH 5.3)(3:1) and the detection wavelength of 247 nm. The working curve from 0.5 to 6.0 microg/ml showed a linear line between the concentrations of AH and the peak areas. There was no interference of peak of AH with the ingredients such as methylparaben, ethylparaben in the lotions, milky lotion and creams.

Comparison of two immunoradiometric assays for serum thyrotropin

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scheinin, B.; Drew, H.; La France, N.

1985-05-01

An ultra-sensitive TSH assay capable of detecting subnormal TSH levels would be useful in confirming suppressed pituitary function as seen in hyperthyroidism. Two sensitive immunoradiometric TSH assays (IRMA's) were studied to determine how well they distinguished thyrotoxic patients from normal subjects. Serono Diagnostics' method employs three monoclonal antibodies specific for different regions of the TSH molecule with a minimum detectable dose (MDD) limit of 0.1 ..mu..IU/ml. Precision studies using a low TSH control in the 1.8 ..mu..IU/ml range gave CV's of 15.0%. Boots-Celltech Diagnostics method is a two site IRMA using two monoclonal antibodies. The MDD limit is 0.05 ..mu..IU/mlmore » with precision CV's of 29.3% at a TSH control range of 0.62 ..mu..IU/ml. In 24 chemically thyrotoxic patients, the mean serum TSH concentration was significantly lower than in the normal control subjects: for Serono, 0.19 ..mu..IU/ml vs. 2.34 ..mu..IU/ml and for Boots Celltech, 0.18 IU/ml vs 2.06 ..mu..IU/ml. The range of TSH was 0 to 0.5 ..mu..IU/ml in thyrotoxic patients using Serono with the exception of one patient having a TSH value of 0.8 ..mu..IU/ml. The normal range was 0.6 to 6.0 ..mu..IU/ml. For Boots Celltech the thyrotoxic range was 0 to 0.2 ..mu..IU/ml with that same thyrotoxic patient giving a TSH value of 0.7 ..mu..IU/ml with a normal range of 0.6 to 5.0 IU/ml. Serum TSH measurements using both procedures are highly sensitive for distinguishing thyrotoxic patients from normal subjects and are useful to confirm suppressed pituitary function.« less

Site response for seattle and source parameters of earthquakes in the puget sound region

USGS Publications Warehouse

Frankel, A.; Carver, D.; Cranswick, E.; Meremonte, M.; Bice, T.; Overturf, D.

1999-01-01

We analyzed seismograms from 21 earthquakes (M(L) 2.0-4.9) recorded by digital seismographs we deployed in urban Seatte to determine site response and earthquake stress drops. The seismometers were situated on a wide variety of geologic units, including artificial fill (e.g., Kingdome, Harbor Island), Pleistocene age soils (glacial till and outwash deposits of Seattle's hills), modified land (downtown Seattle, Space Needle), and Tertiary sedimentary rock. Two mainshock-aftershock sequences were recorded: the June 1997 Bremerton sequence (mainshock M(L) 4.9) and the February 1997 South Seattle sequence (mainshock M(L) 3.5), along with other events in the Puget Sound region. We developed a new inversion procedure to estimate site response, source corner frequencies, and seismic moments from the S-wave spectra. This inversion uses corner frequencies determined from spectral ratios of mainshock-aftershock pairs as constraints. The site responses found from the inversion are not relative to the rock site but are relative to an idealized site with a flat frequency response. The response of the rock site is also found from the inversion. The inversion results show high response for the sites on artificial fill, more moderate amplication for most sites on stiff Pleistocene soils or modified land, and low response for the rock site. Some sites display resonances, such as a strong 2-Hz resonance at our site near the Kingdome, which is caused by the surficial layers of fill and younger alluvium. The sites in West Seattle exhibit high amplification, even though they are on relatively stiff soils of glacial outwash. This may be partly caused by basin surface waves produced by conversion of incident S waves. This high response in West Seattle is consistent with damage reports from the 1949 (m(b) 7.1) and 1965 (m(b) 6.5) earthquakes. Stress-drop estimates for the events we recorded were generally low, between 0.4 and 25 bars, although some of the events may have had higher stress drops that could not be resolved because of the limited passband. We calculated a stress drop of 24 bars for the Bremerton mainshock and 10 bars for the South Seattle mainshock.

Comparative evaluation of technetium-99m-diethylenetriaminepentaacetic acid renal dynamic imaging versus the Modification of Diet in Renal Disease equation and the Chronic Kidney Disease Epidemiology Collaboration equation for the estimation of GFR.

PubMed

Huang, Qi; Chen, Yunshuang; Zhang, Min; Wang, Sihe; Zhang, Weiguang; Cai, Guangyan; Chen, Xiangmei; Sun, Xuefeng

2018-04-01

We compared the performance of technetium-99m-diethylenetriaminepentaacetic acid ( 99m Tc-DTPA) renal dynamic imaging (RDI), the MDRD equation, and the CKD EPI equation to estimate glomerular filtration rate (GFR). A total of 551 subjects, including CKD patients and healthy individuals, were enrolled in this study. Dual plasma sample clearance method of 99m Tc-DTPA was used as the true value for GFR (tGFR). RDI and the MDRD and CKD EPI equations for estimating GFR were compared and evaluated. Data indicate that RDI and the MDRD equation underestimated GFR and CKD EPI overestimated GFR. RDI was associated with significantly higher bias than the MDRD and CKD EPI equations. The regression coefficient, diagnostic precision, and consistency of RDI were significantly lower than either equation. RDI and the MDRD equation underestimated GFR to a greater degree in subjects with tGFR ≥ 90 ml/min/1.73 m 2 compared with the results obtained from all subjects. In the tGFR60-89 ml/min/1.73 m 2 group, the precision of RDI was significantly lower than that of both equations. In the tGFR30-59 ml/min/1.73 m 2 group, RDI had the least bias, the most precision, and significantly higher accuracy compared with either equation. In tGFR < 30 ml/min/1.73 m 2 , the three methods had similar performance and were not significantly different. RDI significantly underestimates GFR and performs no better than MDRD and CKD EPI equations for GFR estimation; thus, it should not be recommended as a reference standard against which other GFR measurement methods are assessed. However, RDI better estimates GFR than either equation for individuals in the tGFR30-59 ml/min/1.73 m 2 group and thus may be helpful to distinguish stage 3a and 3b CKD.

Biofabrication of Ag nanoparticles using Moringa oleifera leaf extract and their antimicrobial activity

PubMed Central

Prasad, TNVKV; Elumalai, EK

2011-01-01

Objective To formulate a simple rapid procedure for bioreduction of silver nanoparticles using aqueous leaves extract of Moringa oleifera (M. oleifera). Methods 10 mL of leaf extract was mixed to 90 mL of 1 mM aqueous of AgNO3 and was heated at 60 - 80 °C for 20 min. A change from brown to reddish color was observed. Characterization using UV-Vis spectrophotometry, Transmission Electron Microscopy (TEM) was performed. Results TEM showed the formation of silver nanoparticles with an average size of 57 nm. Conclusions M. oleifera demonstrates strong potential for synthesis of silver nanoparticles by rapid reduction of silver ions (Ag+ to Ag0). Biological methods are good competents for the chemical procedures, which are eco-friendly and convenient. PMID:23569809

A Test-Length Correction to the Estimation of Extreme Proficiency Levels

ERIC Educational Resources Information Center

Magis, David; Beland, Sebastien; Raiche, Gilles

2011-01-01

In this study, the estimation of extremely large or extremely small proficiency levels, given the item parameters of a logistic item response model, is investigated. On one hand, the estimation of proficiency levels by maximum likelihood (ML), despite being asymptotically unbiased, may yield infinite estimates. On the other hand, with an…

The role of subacromial shoulder irrigation in the treatment of calcific rotator cuff tendinosis: a case series.

PubMed

Vad, Vijay B; Solomon, Jennifer; Adin, David R

2005-06-01

To study the efficacy of subacromial shoulder irrigation in the treatment of calcific rotator cuff tendinosis. Consecutive case series. Musculoskeletal rehabilitation clinic. Twenty-eight tennis players (16 women, 12 men; mean age, 44.3y) with calcific rotator cuff tendinosis, who failed conservative measures. Subjects underwent fluoroscopically guided subacromial shoulder irrigation (50-75 mL of normal saline in 10 mL aliquots) followed by a corticosteroid injection (5 mL solution of 1 mL triamcinolone [40 mg/mL] and 4 mL of 0.5% bupivacaine). After the procedure, all patients completed the same exercise regimen. LInsalata Shoulder Rating Questionnaire (LSRQ) score, visual numeric pain score, and patient satisfaction. At 1-year follow-up, 85.7% reported a successful outcome with significant improvements in the LSQR and numeric pain scores. Our minimally invasive approach was safe, well tolerated, and effective, which should make it useful in providing relief for patients with rotator cuff tendinosis.

Identifying Regional Variation in the Prevalence of Postpartum Haemorrhage: A Systematic Review and Meta-Analysis

PubMed Central

Calvert, Clara; Thomas, Sara L.; Ronsmans, Carine; Wagner, Karen S.; Adler, Alma J.; Filippi, Veronique

2012-01-01

Objective To provide regional estimates of the prevalence of maternal haemorrhage and explore the effect of methodological differences between studies on any observed regional variation. Methods We conducted a systematic review of the prevalence of maternal haemorrhage, defined as blood loss greater than or equal to 1) 500 ml or 2) 1000 ml in the antepartum, intrapartum or postpartum period. We obtained regional estimates of the prevalence of maternal and severe maternal haemorrhage by conducting meta-analyses and used meta-regression to explore potential sources of between-study heterogeneity. Findings No studies reported the prevalence of antepartum haemorrhage (APH) according to our definitions. The prevalence of postpartum haemorrhage (PPH) (blood loss ≥500 ml) ranged from 7.2% in Oceania to 25.7% in Africa. The prevalence of severe PPH (blood loss ≥1000 ml) was highest in Africa at 5.1% and lowest in Asia at 1.9%. There was strong evidence of between-study heterogeneity in the prevalence of PPH and severe PPH in most regions. Meta-regression analyses suggested that region and method of measurement of blood loss influenced prevalence estimates for both PPH and severe PPH. The regional patterns changed after adjusting for the other predictors of PPH indicating that, compared with European women, Asian women have a lower prevalence of PPH. Conclusions We found evidence that Asian women have a very low prevalence of PPH compared with women in Europe. However, more reliable estimates will only be obtained with the standardisation of the measurement of PPH so that the data from different regions are comparable. PMID:22844432

A Practical Methylation Procedure for (1H)-1,2,4-Triazole (Preprint)

DTIC Science & Technology

2007-06-01

on alkylations with higher molecular weight electrophiles, rather than on synthesizing the methyl homologue, the simple reaction to obtain the...an equivalent of the 25% w/w methanolic sodium methoxide solution with heating to 65 °C for 5 minutes in a 5 mL sealed microwave reaction vessel ...requisite neat iodomethane, and recrimping the 5 mL reaction vessel , the reaction vessel was reinserted into the microwave apparatus . The reaction mixture

Preprocedural statin therapy reduces the risk and extent of cardiac biomarker release following percutaneous coronary intervention.

PubMed

Veselka, Josef; Procházková, Sárka; Duchonová, Radka; Homolová, Ingrid; Tesar, David; Bybee, Kevin A

2006-05-01

This study evaluates the association between statin therapy in patients treated by percutaneous coronary intervention (PCI) for stable angina pectoris and postinterventional myocardial injury with subsequent long-term clinical outcome. Prospectively collected data on 400 consecutive patients with stable angina pectoris or evidence of inducible myocardial ischemia were analyzed. The incidence of myocardial infarction based on postinterventional release of troponin I>1.5 ng/ml was 12% in the statin pretreated patients and 20% in those not pretreated with statin therapy (P=0.04, odds ratio 1.84, 95% confidence interval 1.06-3.21). Of the patients experiencing a post-PCI troponin elevation>1.5 ng/ml, those pretreated with a statin pre-PCI had a lesser troponin elevation compared with those not receiving a statin pre-PCI (median: 2.9 ng/ml [1.9-11.5] vs 5.0 ng/ml [3.1-8.8]; P<0.001). In the multivariate model, preprocedural statin therapy was identified as the only independent negative predictor of procedure-related myocardial necrosis based on postprocedural troponin elevation. In the 21-month follow-up period, statin pretreated patients were observed to have fewer deaths, revascularizations, or myocardial infarction; however, this difference was not statistically significant. These results suggest that pretreatment with statins in patients undergoing PCI for stable angina pectoris reduces the risk and extent of procedure-related myocardial injury measured by troponin release.

Determination of homovanillic acid (HVA) in human plasma by HPLC with coulometric detection and a new SPE procedure.

PubMed

Saracino, M A; Mandrioli, R; Mercolini, L; Ferranti, A; Zaimovic, A; Leonardi, C; Raggi, M A

2006-09-11

A sensitive high-performance liquid chromatographic method has been developed for the determination of homovanillic acid (HVA), the main metabolite of dopamine, in human plasma. Analyses were carried out on a reversed-phase column (C8, 250 mm x 4.6 mm i.d., 5 microm) using a mobile phase composed of 10% methanol and 90% aqueous citrate buffer, containing octanesulfonic acid and EDTA at pH 4.8. Coulometric detection was used, setting the guard cell at +0.100 V, the first analytical cell at -0.200 V and the second analytical cell at +0.500 V. A careful solid-phase extraction procedure, based on strong anion exchange (SAX) cartridges (100 mg, 1 mL), was implemented for the pre-treatment of plasma samples. Extraction yield was satisfactory, being the mean value 98.0%. The calibration curve was linear over the concentration range of 0.2-25.0 ng mL(-1) of homovanillic acid. The limit of quantitation (LOQ) was 0.2 ng mL(-1) and the limit of detection (LOD) was 0.1 ng mL(-1). The method was successfully applied to plasma samples from former alcohol, cocaine and heroin addicts. Results were satisfactory in terms of precision and accuracy. Hence, the method is suitable for the determination of homovanillic acid in human plasma.

Analyzing latent state-trait and multiple-indicator latent growth curve models as multilevel structural equation models

PubMed Central

Geiser, Christian; Bishop, Jacob; Lockhart, Ginger; Shiffman, Saul; Grenard, Jerry L.

2013-01-01

Latent state-trait (LST) and latent growth curve (LGC) models are frequently used in the analysis of longitudinal data. Although it is well-known that standard single-indicator LGC models can be analyzed within either the structural equation modeling (SEM) or multilevel (ML; hierarchical linear modeling) frameworks, few researchers realize that LST and multivariate LGC models, which use multiple indicators at each time point, can also be specified as ML models. In the present paper, we demonstrate that using the ML-SEM rather than the SL-SEM framework to estimate the parameters of these models can be practical when the study involves (1) a large number of time points, (2) individually-varying times of observation, (3) unequally spaced time intervals, and/or (4) incomplete data. Despite the practical advantages of the ML-SEM approach under these circumstances, there are also some limitations that researchers should consider. We present an application to an ecological momentary assessment study (N = 158 youths with an average of 23.49 observations of positive mood per person) using the software Mplus (Muthén and Muthén, 1998–2012) and discuss advantages and disadvantages of using the ML-SEM approach to estimate the parameters of LST and multiple-indicator LGC models. PMID:24416023

The Case of the Soft-Shelled Egg.

ERIC Educational Resources Information Center

Cocanour, Barbara; Bruce, Alease S.

1986-01-01

Offers suggestions for activities that demonstrate the principles of osmosis. Explains how decalcified chicken eggs can be used to give students practice with measurement, experimental procedures, and science principles. (ML)

libNeuroML and PyLEMS: using Python to combine procedural and declarative modeling approaches in computational neuroscience.

PubMed

Vella, Michael; Cannon, Robert C; Crook, Sharon; Davison, Andrew P; Ganapathy, Gautham; Robinson, Hugh P C; Silver, R Angus; Gleeson, Padraig

2014-01-01

NeuroML is an XML-based model description language, which provides a powerful common data format for defining and exchanging models of neurons and neuronal networks. In the latest version of NeuroML, the structure and behavior of ion channel, synapse, cell, and network model descriptions are based on underlying definitions provided in LEMS, a domain-independent language for expressing hierarchical mathematical models of physical entities. While declarative approaches for describing models have led to greater exchange of model elements among software tools in computational neuroscience, a frequent criticism of XML-based languages is that they are difficult to work with directly. Here we describe two Application Programming Interfaces (APIs) written in Python (http://www.python.org), which simplify the process of developing and modifying models expressed in NeuroML and LEMS. The libNeuroML API provides a Python object model with a direct mapping to all NeuroML concepts defined by the NeuroML Schema, which facilitates reading and writing the XML equivalents. In addition, it offers a memory-efficient, array-based internal representation, which is useful for handling large-scale connectomics data. The libNeuroML API also includes support for performing common operations that are required when working with NeuroML documents. Access to the LEMS data model is provided by the PyLEMS API, which provides a Python implementation of the LEMS language, including the ability to simulate most models expressed in LEMS. Together, libNeuroML and PyLEMS provide a comprehensive solution for interacting with NeuroML models in a Python environment.

libNeuroML and PyLEMS: using Python to combine procedural and declarative modeling approaches in computational neuroscience

PubMed Central

Vella, Michael; Cannon, Robert C.; Crook, Sharon; Davison, Andrew P.; Ganapathy, Gautham; Robinson, Hugh P. C.; Silver, R. Angus; Gleeson, Padraig

2014-01-01

NeuroML is an XML-based model description language, which provides a powerful common data format for defining and exchanging models of neurons and neuronal networks. In the latest version of NeuroML, the structure and behavior of ion channel, synapse, cell, and network model descriptions are based on underlying definitions provided in LEMS, a domain-independent language for expressing hierarchical mathematical models of physical entities. While declarative approaches for describing models have led to greater exchange of model elements among software tools in computational neuroscience, a frequent criticism of XML-based languages is that they are difficult to work with directly. Here we describe two Application Programming Interfaces (APIs) written in Python (http://www.python.org), which simplify the process of developing and modifying models expressed in NeuroML and LEMS. The libNeuroML API provides a Python object model with a direct mapping to all NeuroML concepts defined by the NeuroML Schema, which facilitates reading and writing the XML equivalents. In addition, it offers a memory-efficient, array-based internal representation, which is useful for handling large-scale connectomics data. The libNeuroML API also includes support for performing common operations that are required when working with NeuroML documents. Access to the LEMS data model is provided by the PyLEMS API, which provides a Python implementation of the LEMS language, including the ability to simulate most models expressed in LEMS. Together, libNeuroML and PyLEMS provide a comprehensive solution for interacting with NeuroML models in a Python environment. PMID:24795618

46 CFR Appendix III to Part 150 - Testing Procedures for Determining Exceptions to the Chart

Code of Federal Regulations, 2014 CFR

2014-10-01

... provided with shields. Testing chemicals other than liquids—The procedure outlined below was developed for... test tube to a stand behind a safety shield (in a hood). Carefully add from a dropper 0.5ml of the... mixture. The Dewar flask is equipped with a magnetic stirrer having a stirring bar coated with an inert...

46 CFR Appendix III to Part 150 - Testing Procedures for Determining Exceptions to the Chart

Code of Federal Regulations, 2012 CFR

2012-10-01

... provided with shields. Testing chemicals other than liquids—The procedure outlined below was developed for... test tube to a stand behind a safety shield (in a hood). Carefully add from a dropper 0.5ml of the... mixture. The Dewar flask is equipped with a magnetic stirrer having a stirring bar coated with an inert...

46 CFR Appendix III to Part 150 - Testing Procedures for Determining Exceptions to the Chart

Code of Federal Regulations, 2013 CFR

2013-10-01

... provided with shields. Testing chemicals other than liquids—The procedure outlined below was developed for... test tube to a stand behind a safety shield (in a hood). Carefully add from a dropper 0.5ml of the... mixture. The Dewar flask is equipped with a magnetic stirrer having a stirring bar coated with an inert...

Bootstrap Standard Errors for Maximum Likelihood Ability Estimates When Item Parameters Are Unknown

ERIC Educational Resources Information Center

Patton, Jeffrey M.; Cheng, Ying; Yuan, Ke-Hai; Diao, Qi

2014-01-01

When item parameter estimates are used to estimate the ability parameter in item response models, the standard error (SE) of the ability estimate must be corrected to reflect the error carried over from item calibration. For maximum likelihood (ML) ability estimates, a corrected asymptotic SE is available, but it requires a long test and the…

Estimator banks: a new tool for direction-of-arrival estimation

NASA Astrophysics Data System (ADS)

Gershman, Alex B.; Boehme, Johann F.

1997-10-01

A new powerful tool for improving the threshold performance of direction-of-arrival (DOA) estimation is considered. The essence of our approach is to reduce the number of outliers in the threshold domain using the so-called estimator bank containing multiple 'parallel' underlying DOA estimators which are based on pseudorandom resampling of the MUSIC spatial spectrum for given data batch or sample covariance matrix. To improve the threshold performance relative to conventional MUSIC, evolutionary principles are used, i.e., only 'successful' underlying estimators (having no failure in the preliminary estimated source localization sectors) are exploited in the final estimate. An efficient beamspace root implementation of the estimator bank approach is developed, combined with the array interpolation technique which enables the application to arbitrary arrays. A higher-order extension of our approach is also presented, where the cumulant-based MUSIC estimator is exploited as a basic technique for spatial spectrum resampling. Simulations and experimental data processing show that our algorithm performs well below the MUSIC threshold, namely, has the threshold performance similar to that of the stochastic ML method. At the same time, the computational cost of our algorithm is much lower than that of stochastic ML because no multidimensional optimization is involved.

Frequency-area distribution of earthquake-induced landslides

NASA Astrophysics Data System (ADS)

Tanyas, H.; Allstadt, K.; Westen, C. J. V.

2016-12-01

Discovering the physical explanations behind the power-law distribution of landslides can provide valuable information to quantify triggered landslide events and as a consequence to understand the relation between landslide causes and impacts in terms of environmental settings of landslide affected area. In previous studies, the probability of landslide size was utilized for this quantification and the developed parameter was called a landslide magnitude (mL). The frequency-area distributions (FADs) of several landslide inventories were modelled and theoretical curves were established to identify the mL for any landslide inventory. In the observed landslide inventories, a divergence from the power-law distribution was recognized for the small landslides, referred to as the rollover, and this feature was taken into account in the established model. However, these analyses are based on a relatively limited number of inventories, each with a different triggering mechanism. Existing definition of the mL include some subjectivity, since it is based on a visual comparison between the theoretical curves and the FAD of the medium and large landslides. Additionally, the existed definition of mL introduces uncertainty due to the ambiguity in both the physical explanation of the rollover and its functional form. Here we focus on earthquake-induced landslides (EQIL) and aim to provide a rigorous method to estimate the mL and total landslide area of EQIL. We have gathered 36 EQIL inventories from around the globe. Using these inventories, we have evaluated existing explanations of the rollover and proposed an alternative explanation given the new data. Next, we propose a method to define the EQIL FAD curves, mL and to estimate the total landslide area. We utilize the total landslide areas obtained from inventories to compare them with our estimations and to validate our methodology. The results show that we calculate landslide magnitudes more accurately than previous methods.

Diminished Baroreflex Control of Forearm Vascular Resistance Following Training

NASA Technical Reports Server (NTRS)

Mack, G. W.; Thompson, C. A.; Doerr, D. F.; Nadel, E. R.; Convertino, V. A.

1991-01-01

The stimulus-response characteristics of cardiopulmonary baroreflex control of forearm vascular resistance (FVR units in mm Hg x min x I00 ml/ml) were studied in 14 volunteers before and after 10 wk of endurance training. We assessed the relationship betaleen reflex stimulus (changes in central venous pressure, CVP) and response (FVR) during unloading of cardiopulmonary baroreceptors with lower body negative pressure (LBNP, 0 to - 2O mm Hg). Changes in CVP during LBNP were estimated from pressure changes in a large peripheral vein in the dependent arm of the subject in the right lateral decubitus position. Maximal oxygen uptake (VO(sub 2max)) and total blood volume increased with endurance training from 37.8 +/- 1.4 ml/min x kg and 63.6 +/- 2.1 ml/kg to 45.3 +/- 1.4 ml/ min x kg and 69.3 +/- 2.8 ml/kg respectively (P less than 0.05). Reflex forearm vasoconstriction occurred in response to a reduction in estimated CVP, and the absolute change in FVR per unit of CVP was reduced from -5.96 +/- 0.79 to -4.06 +/- 0.52 units x mm/ Hg (P less than 0.05) following exercise training but was unchanged from -6.10 to 0.57 to -6.22 +/- 0.94 units x mm/ Hg for the time control group (N = 7). Resting values for FVR were similar before and after exercise training; however, resting estimated CVP was elevated from 9.5 +/- 0.5 mm x Hg before training to 11.3 +/- 0.6 mm x Hg after training. The reduction in sensitivity of the cardiopulmonary baroreflex control of FVR was linearly related to the increase in blood volume (r = 0.65, P less than 0.05). suggesting that diminished cardiopulmonary baroreflex control of FVR in physically fit individuals is related, in part, to a training-induced blood volume expansion.

Influence of ammonium hydroxide solution on LiMn2O4 nanostructures prepared by modified chemical bath method

NASA Astrophysics Data System (ADS)

Koao, Lehlohonolo F.; Motloung, Setumo V.; Motaung, Tshwafo E.; Kebede, Mesfin A.

2018-04-01

LiMn2O4 (LMO) powders were prepared by modified chemical bath deposition (CBD) method by varying ammonium hydroxide solution (AHS). The volume of the AHS was varied from 5 to 120 mL in order to determine the optimum volume that is needed for preparation of LMO powders. The effect of AHS volume on the structure, morphology, and electrochemical properties of LMO powders was investigated. The X-ray diffraction (XRD) patterns of the LMO powders correspond to the cubic spinel LMO phase. It was found that the XRD peaks increased in intensity with increasing volume of the AHS up to 20 mL. The estimated average grain sizes calculated using the XRD patterns were found to be in the order of 66 ± 1 nm. It was observed that the estimated average grain sizes increased up to 20 mL of AHS. The scanning electron microscopy (SEM) results revealed that the AHS volume does not influence the surface morphology of the prepared nano-powders. Elemental energy dispersive (EDS) analysis mapping conducted on the samples revealed homogeneous distribution of Mn and O for the sample synthesized with 120 mL of AHS. The UV-Vis spectra showed a red shift with an increase in AHS up 20 mL. The cyclic voltammetry and galvanostatic charge/discharge cycle testing confirmed that 20 mL of AHS has superior lithium ion kinetics and electrochemical performance.

Validating a faster method for reconstitution of Crotalidae Polyvalent Immune Fab (ovine).

PubMed

Gerring, David; King, Thomas R; Branton, Richard

2013-07-01

Reconstitution of CroFab(®) (Crotalidae Polyvalent Immune Fab [ovine]) lyophilized drug product was previously performed using 10 mL sterile water for injection followed by up to 36 min of gentle swirling of the vial. CroFab has been clinically demonstrated to be most effective when administered within 6 h of snake envenomation, and improved clinical outcomes are correlated with quicker timing of administration. An alternate reconstitution method was devised, using 18 mL 0.9% saline with manual inversion, with the goal of shortening reconstitution time while maintaining a high quality, efficacious product. An analytical study was designed to compare the physicochemical properties of 3 separate batches of CroFab when reconstituted using the standard procedure (10 mL WFI with gentle swirling) and a modified rapid procedure using 18 mL 0.9% saline and manual inversion. The physical and chemical characteristics of the same 3 batches were assessed using various analytic methodologies associated with routine quality control release testing. In addition further analytical methodologies were applied in order to elucidate possible structural changes that may be induced by the changed reconstitution procedure. Batches A, B, and C required mean reconstitution times of 25 min 51 s using the label method and 3 min 07 s (a 88.0% mean decrease) using the modified method. Physicochemical characteristics (color and clarity, pH, purity, protein content, potency) were found to be highly comparable. Characterization assays (dynamic light scattering, analytical ultracentrifugation, LC-MS, SDS-PAGE and circular dichroism spectroscopy were also all found to be comparable between methods. When comparing CroFab batches that were reconstituted using the labeled and modified methods, the physicochemical and biological (potency) characteristics of CroFab were not significantly changed when challenged by the various standard analytical methodologies applied in routine quality control analysis. Additionally, no changes in the CroFab molecule regarding degradation, aggregation, purity, structure, or mass were observed. The analyses performed validated the use of the more rapid reconstitution method using 18 mL 0.9% saline in order to allow a significantly reduced time to administration of CroFab to patients in need. Copyright © 2013 Elsevier Ltd. All rights reserved.

Hypovitaminosis D in Bariatric Surgery: A Systematic Review of Observational Studies

PubMed Central

Chakhtoura, M; Nakhoul, N; Shawwa, K; Mantzoros, C; El Hajj Fuleihan, G

2016-01-01

Background Obesity is a public health problem that carries global and substantial social and economic burden. Relative to non-surgical interventions, bariatric surgery has the most substantial and lasting impact on weight loss. However, it leads to a number of nutritional deficiencies requiring long term supplementation. Objectives The aims of this paper are to review 25-hydroxyvitamin D [25(OH)D] status pre and post - bariatric surgery, describe the dose response of vitamin D supplementation, and assess the effect of the surgical procedure on 25(OH)D level following supplementation. Methods We searched Medline, PubMed, the Cochrane Library and EMBASE, for relevant observational studies published in English, from 2000–April 2015. The identified references were reviewed, in duplicate and independently, by two reviewers. Results We identified 51 eligible observational studies assessing 25(OH)D status pre and/or post bariatric surgery. Mean pre-surgery 25(OH)D level was below 30 ng/ml in 29 studies and 17 of these studies showed mean 25(OH)D levels ≤ 20 ng/ml. Mean 25(OH)D levels remained below 30 ng/ml following bariatric surgery despite various vitamin D replacement regimens, with only few exceptions. The increase in postoperative 25(OH)D levels tended to parallel increments in vitamin D supplementation dose but varied widely across studies. An increase in 25(OH)D level by 9–13 ng/ml was achieved when vitamin D deficiency was corrected using vitamin D replacement doses of 1,100–7,100 IU/day, in addition to the usual maintenance equivalent daily dose of 400 – 2,000 IU (total equivalent daily dose 1,500–9,150 IU). There was no difference in mean 25(OH)D level following supplementation between malabsorptive/ combination procedures and restrictive procedures. Conclusion Hypovitaminosisis D persists in obese patients undergoing bariatric surgery, despite various vitamin D supplementation regimens. Further research is needed to determine the optimal vitamin D dose to reach desirable 25(OH)D levels in this population, and to demonstrate whether this dose varies according to the surgical procedure. PMID:26805016

40 CFR 98.385 - Procedures for estimating missing data.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Procedures for estimating missing data... Procedures for estimating missing data. You must follow the procedures for estimating missing data in § 98... estimating missing data for petroleum products in § 98.395 also applies to coal-to-liquid products. ...

40 CFR 98.385 - Procedures for estimating missing data.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 22 2012-07-01 2012-07-01 false Procedures for estimating missing data... Procedures for estimating missing data. You must follow the procedures for estimating missing data in § 98... estimating missing data for petroleum products in § 98.395 also applies to coal-to-liquid products. ...

40 CFR 98.385 - Procedures for estimating missing data.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Procedures for estimating missing data... Procedures for estimating missing data. You must follow the procedures for estimating missing data in § 98... estimating missing data for petroleum products in § 98.395 also applies to coal-to-liquid products. ...

40 CFR 98.385 - Procedures for estimating missing data.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 21 2011-07-01 2011-07-01 false Procedures for estimating missing data... Procedures for estimating missing data. You must follow the procedures for estimating missing data in § 98... estimating missing data for petroleum products in § 98.395 also applies to coal-to-liquid products. ...

40 CFR 98.385 - Procedures for estimating missing data.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Procedures for estimating missing data... Procedures for estimating missing data. You must follow the procedures for estimating missing data in § 98... estimating missing data for petroleum products in § 98.395 also applies to coal-to-liquid products. ...

Endoscopic excavation for gastric heterotopic pancreas: an analysis of 42 cases from a tertiary center.

PubMed

Zhang, Yu; Huang, Qin; Zhu, Lin-hong; Zhou, Xian-bin; Ye, Li-ping; Mao, Xin-li

2014-09-01

Because of the difficulty associated with making an accurate diagnosis of gastric heterotopic pancreas (HP) before surgery, surgical resection is usually performed in suspected cases. However, this is an invasive procedure and prone to certain surgical complications. This study was designed to evaluate the feasibility of endoscopic excavation for gastric HP, as well as the value of endoscopic ultrasonography (EUS) in diagnosing gastric HP. Between January 2007 and January 2013, 42 consecutive patients with gastric HP were enrolled in this retrospective study. Key steps: (1) Injection of a solution (100 ml saline + 2 ml indigo carmine + 1 ml epinephrine) into the submucosal layer after making several dots around the lesion; (2) Incision of the mucosa outside the marker dots with a needle-knife, and then circumferential excavation until complete resection of the lesion; (3) Closure of the artificial ulcer with several clips after tumor removal. In this study, 18 cases (42.9%) were suspected as gastric HP (assessed by two experienced endoscopists before endoscopic excavation), 8 (19.0%) were suspected as gastrointestinal stromal tumors, 7 (16.7%) as gastric polyp, and the remaining 9 cases (21.4%) were still unknown. The mean procedure duration was 28.6 min. En bloc resection by endoscopic excavation was achieved in 40 cases (95.2%), and no massive bleeding, delayed bleeding, perforation, or other severe complication occurred in these patients. Among the 42 lesions, a tube echo could be detected in 11 cases by EUS. Those 11 cases were diagnosed as gastric HP by histopathology. Endoscopic excavation appears to be a safe and feasible procedure for accurate histopathologic evaluation and curative treatment in gastric HP. Use of EUS has some value in the diagnosis of gastric HP before the procedure

Stochastic approach to data analysis in fluorescence correlation spectroscopy.

PubMed

Rao, Ramachandra; Langoju, Rajesh; Gösch, Michael; Rigler, Per; Serov, Alexandre; Lasser, Theo

2006-09-21

Fluorescence correlation spectroscopy (FCS) has emerged as a powerful technique for measuring low concentrations of fluorescent molecules and their diffusion constants. In FCS, the experimental data is conventionally fit using standard local search techniques, for example, the Marquardt-Levenberg (ML) algorithm. A prerequisite for these categories of algorithms is the sound knowledge of the behavior of fit parameters and in most cases good initial guesses for accurate fitting, otherwise leading to fitting artifacts. For known fit models and with user experience about the behavior of fit parameters, these local search algorithms work extremely well. However, for heterogeneous systems or where automated data analysis is a prerequisite, there is a need to apply a procedure, which treats FCS data fitting as a black box and generates reliable fit parameters with accuracy for the chosen model in hand. We present a computational approach to analyze FCS data by means of a stochastic algorithm for global search called PGSL, an acronym for Probabilistic Global Search Lausanne. This algorithm does not require any initial guesses and does the fitting in terms of searching for solutions by global sampling. It is flexible as well as computationally faster at the same time for multiparameter evaluations. We present the performance study of PGSL for two-component with triplet fits. The statistical study and the goodness of fit criterion for PGSL are also presented. The robustness of PGSL on noisy experimental data for parameter estimation is also verified. We further extend the scope of PGSL by a hybrid analysis wherein the output of PGSL is fed as initial guesses to ML. Reliability studies show that PGSL and the hybrid combination of both perform better than ML for various thresholds of the mean-squared error (MSE).

Ultrasound-guided thoracenthesis: the V-point as a site for optimal drainage positioning.

PubMed

Zanforlin, A; Gavelli, G; Oboldi, D; Galletti, S

2013-01-01

In the latest years the use of lung ultrasound is increasing in the evaluation of pleural effusions, because it makes follow-up easier and drainage more efficient by providing guidance on the most appropriate sampling site. However, no standardized approach for ultrasound-guided thoracenthesis is actually available. To evaluate our usual ultrasonographic landmark as a possible standard site to perform thoracenthesis by assessing its value in terms of safety and efficiency (success at first attempt, drainage as complete as possible). Hospitalized patients with non organized pleural effusion underwent thoracenthesis after ultrasound evaluation. The point showing on ultrasound the maximum thickness of the effusion ("V-point") was chosen for drainage. 45 ultrasound guided thoracenthesis were performed in 12 months. In 22 cases there were no complications; 16 cases of cough, 2 cases of mild dyspnea without desaturation, 4 cases of mild pain; 2 cases of complications requiring medical intervention occurred. No case of pneumothorax related to the procedure was detected. In all cases drainage was successful on the first attempt. The collected values of maximum thickness at V-point (min 3.4 cm - max 15.3 cm) and drained fluid volume (min 70 ml - max 2000 ml) showed a significative correlation (p < 0.0001). When the thickness was greater or equal to 9.9 cm, drained volume was always more than 1000 ml. The measure of the maximum thickness at V-point provides high efficiency to ultrasound guided thoracentesis and allows to estimate the amount of fluid in the pleural cavity. It is also an easy parameter that makes the proposed method quick to learn and apply.  

Characterization of long-term elution of platinum from carboplatin-impregnated calcium sulfate hemihydrate beads in vitro by two distinct sample collection methods.

PubMed

Tulipan, Rachel J; Phillips, Heidi; Garrett, Laura D; Dirikolu, Levent; Mitchell, Mark A

2017-05-01

OBJECTIVE To characterize long-term elution of platinum from carboplatin-impregnated calcium sulfate hemihydrate (CI-CSH) beads in vitro by comparing 2 distinct sample collection methods designed to mimic 2 in vivo environments. SAMPLES 162 CI-CSH beads containing 4.6 mg of carboplatin (2.4 mg of platinum/bead). PROCEDURES For method 1, which mimicked an in vivo environment with rapid and complete fluid exchange, each of 3 plastic 10-mL conical tubes contained 3 CI-CSH beads and 5 mL of PBS solution. Eluent samples were obtained by evacuation of all fluid at 1, 2, 3, 6, 9, and 12 hours and 1, 2, 3, 6, 9, 12, 15, 18, 22, 26, and 30 days. Five milliliters of fresh PBS solution was then added to each tube. For method 2, which mimicked an in vivo environment with no fluid exchange, each of 51 tubes (ie, 3 tubes/17 sample collection times) contained 3 CI-CSH beads and 5 mL of PBS solution. Eluent samples were obtained from the assigned tubes for each time point. All samples were analyzed for platinum content by inductively coupled plasma-mass spectrometry. RESULTS Platinum was released from CI-CSH beads for 22 to 30 days. Significant differences were found in platinum concentration and percentage of platinum eluted from CI-CSH beads over time for each method. Platinum concentrations and elution percentages in method 2 samples were significantly higher than those of method 1 samples, except for the first hour measurements. CONCLUSIONS AND CLINICAL RELEVANCE Sample collection methods 1 and 2 may provide estimates of the minimum and maximum platinum release, respectively, from CI-CSH beads in vivo.

The Applicability of Confidence Intervals of Quantiles for the Generalized Logistic Distribution

NASA Astrophysics Data System (ADS)

Shin, H.; Heo, J.; Kim, T.; Jung, Y.

2007-12-01

The generalized logistic (GL) distribution has been widely used for frequency analysis. However, there is a little study related to the confidence intervals that indicate the prediction accuracy of distribution for the GL distribution. In this paper, the estimation of the confidence intervals of quantiles for the GL distribution is presented based on the method of moments (MOM), maximum likelihood (ML), and probability weighted moments (PWM) and the asymptotic variances of each quantile estimator are derived as functions of the sample sizes, return periods, and parameters. Monte Carlo simulation experiments are also performed to verify the applicability of the derived confidence intervals of quantile. As the results, the relative bias (RBIAS) and relative root mean square error (RRMSE) of the confidence intervals generally increase as return period increases and reverse as sample size increases. And PWM for estimating the confidence intervals performs better than the other methods in terms of RRMSE when the data is almost symmetric while ML shows the smallest RBIAS and RRMSE when the data is more skewed and sample size is moderately large. The GL model was applied to fit the distribution of annual maximum rainfall data. The results show that there are little differences in the estimated quantiles between ML and PWM while distinct differences in MOM.

Single Incision Laparoscopic Pancreas Resection for Pancreatic Metastasis of Renal Cell Carcinoma

PubMed Central

Sümer, Aziz; Demirel, Tugrul; Karakullukçu, Nazlι; Batman, Burçin; İçscan, Yalιn; Sarιçam, Gülay; Serin, Kürçsat; Loh, Wei-Liang; Dinççağ, Ahmet; Mercan, Selçuk

2010-01-01

Background: Transumbilical single incision laparoscopic surgery (SILS) offers excellent cosmetic results and may be associated with decreased postoperative pain, reduced need for analgesia, and thus accelerated recovery. Herein, we report the first transumbilical single incision laparoscopic pancreatectomy case in a patient who had renal cell cancer metastasis on her pancreatic corpus and tail. Methods: A 59-year-old female who had metastatic lesions on her pancreas underwent laparoscopic subtotal pancreatectomy through a 2-cm umbilical incision. Results: Single incision pancreatectomy was performed with a special port (SILS port) and articulated equipment. The procedure lasted 330 minutes. Estimated blood loss was 100mL. No perioperative complications occurred. The patient was discharged on the seventh postoperative day with a low-volume (20mL/day) pancreatic fistula that ceased spontaneously. Pathology result of the specimen was renal cell cancer metastases. Conclusion: This is the first reported SILS pancreatectomy case, demonstrating that even advanced surgical procedures can be performed using the SILS technique in well-experienced centers. Transumbilical single incision laparoscopic pancreatectomy is feasible and can be performed safely in experienced centers. SILS may improve cosmetic results and allow accelerated recovery for patients even with malignancy requiring advanced laparoscopic interventions. PMID:21605524

Single incision laparoscopic pancreas resection for pancreatic metastasis of renal cell carcinoma.

PubMed

Barbaros, Umut; Sümer, Aziz; Demirel, Tugrul; Karakullukçu, Nazlı; Batman, Burçin; Içscan, Yalın; Sarıçam, Gülay; Serin, Kürçsat; Loh, Wei-Liang; Dinççağ, Ahmet; Mercan, Selçuk

2010-01-01

Transumbilical single incision laparoscopic surgery (SILS) offers excellent cosmetic results and may be associated with decreased postoperative pain, reduced need for analgesia, and thus accelerated recovery. Herein, we report the first transumbilical single incision laparoscopic pancreatectomy case in a patient who had renal cell cancer metastasis on her pancreatic corpus and tail. A 59-year-old female who had metastatic lesions on her pancreas underwent laparoscopic subtotal pancreatectomy through a 2-cm umbilical incision. Single incision pancreatectomy was performed with a special port (SILS port) and articulated equipment. The procedure lasted 330 minutes. Estimated blood loss was 100mL. No perioperative complications occurred. The patient was discharged on the seventh postoperative day with a low-volume (20mL/day) pancreatic fistula that ceased spontaneously. Pathology result of the specimen was renal cell cancer metastases. This is the first reported SILS pancreatectomy case, demonstrating that even advanced surgical procedures can be performed using the SILS technique in well-experienced centers. Transumbilical single incision laparoscopic pancreatectomy is feasible and can be performed safely in experienced centers. SILS may improve cosmetic results and allow accelerated recovery for patients even with malignancy requiring advanced laparoscopic interventions.

Randomized trial of one-hour sodium bicarbonate vs standard periprocedural saline hydration in chronic kidney disease patients undergoing cardiovascular contrast procedures.

PubMed

Kooiman, Judith; de Vries, Jean-Paul P M; Van der Heyden, Jan; Sijpkens, Yvo W J; van Dijkman, Paul R M; Wever, Jan J; van Overhagen, Hans; Vahl, Antonie C; Aarts, Nico; Verberk-Jonkers, Iris J A M; Brulez, Harald F H; Hamming, Jaap F; van der Molen, Aart J; Cannegieter, Suzanne C; Putter, Hein; van den Hout, Wilbert B; Kilicsoy, Inci; Rabelink, Ton J; Huisman, Menno V

2018-01-01

Guidelines advise periprocedural saline hydration for prevention of contrast induced-acute kidney injury (CI-AKI). We analysed whether 1-hour sodium bicarbonate hydration administered solely prior to intra-arterial contrast exposure is non-inferior to standard periprocedural saline hydration in chronic kidney disease (CKD) patients undergoing elective cardiovascular diagnostic or interventional contrast procedures. We performed an open-label multicentre non-inferiority trial between 2011-2014. Patients were randomized to 1 hour pre-procedure sodium bicarbonate hydration (250 ml 1.4%, N = 168) or 4-12 hours saline hydration (1000 ml 0.9%, N = 165) prior to and following contrast administration (2000 ml of saline total). Primary outcome was the relative serum creatinine increase (%) 48-96 hours post contrast exposure. Secondary outcomes were: incidence of CI-AKI (serum creatinine increase>25% or >44μmol/L), recovery of renal function, the need for dialysis, and hospital costs within two months follow-up. Mean relative creatinine increase was 3.1% (95%CI 0.9 to 5.2%) in the bicarbonate and 1.1% (95%CI -1.2 to 3.5%) in the saline arm, mean difference 1.9% (95%CI -1.2 to 5.1%, p-non-inferiority <0.001). CI-AKI occurred in 11 (6.7%) patients randomized to sodium bicarbonate and 12 (7.5%) to saline (p = 0.79). Renal function did not fully recover in 40.0% and 44.4% of CI-AKI patients, respectively (p = 0.84). No patient required dialysis. Mean costs for preventive hydration and clinical preparation for the contrast procedure were $1158 for sodium bicarbonate vs. $1561 for saline (p < 0.001). Short hydration with sodium bicarbonate prior to elective cardiovascular diagnostic or therapeutic contrast procedures is non-inferior to standard periprocedural saline hydration in CKD patients with respect to renal safety and results in considerable healthcare savings. Netherlands Trial Register (http://www.trialregister.nl/trialreg/index.asp), Nr NTR2699.

Matrix solid phase dispersion assisted enzymatic hydrolysis as a novel approach for cocaine and opiates isolation from human hair.

PubMed

Míguez-Framil, Martha; Cabarcos, Pamela; Tabernero, María Jesús; Bermejo, Ana María; Bermejo-Barrera, Pilar; Moreda-Piñeiro, Antonio

2013-11-05

The possibility of assisting enzymatic hydrolysis (EH) procedures by sample disruption mechanisms inherent to matrix solid phase dispersion (MSPD) has been explored in the current study. EH of hair specimens from poly-drug abusers was assisted by dispersing/blending the sample (0.05 g) with alumina (2.25 g) before loading the dissolved enzyme (6 mL of 1 mg mL(-1) Pronase E in 1.4 M/1.4 M Tris/HCl, pH 7.3) through the hair-alumina solid phase packaged inside a disposable MSPD syringe. The MSPD-EH method was developed, and it proved to offer quantitative results when isolating cocaine, benzoylecgonine (BZE), codeine, morphine and 6-monoacethylmorphine (6-MAM) from human hair samples. The procedure allows an on column clean-up/pre-concentration procedure of the isolated targets by attaching a previously conditioned Oasis HLB cartridge to the end of the MSPD syringe. The EH procedure of human hair with Pronase E can therefore be shortened to approximately 30 min. Within this time, sample blending/dispersion, MSPD syringe package, elution (EH when dissolved Pronase E is passing through the sample-dispersant bed), and extract clean-up and target pre-concentration stages are achieved. Gas chromatography-mass spectrometry (GC-MS) was used for determining each target after elution from the Oasis HLB cartridges with 2 mL of 2% (v/v) acetic acid in methanol, concentration by N2 stream evaporation, and dried extract derivatization with N-methyl-tert-butylsilyltrifluoroacetamide (BSTFA) and chlorotrimethylsilane (TMCS). The method was validated according to the guidance for bioanalytical method validation of the US Department of Health and Human Services, Food and Drug Administration. The simplicity of the proposed approach makes it a useful procedure for screening/quantifying drugs of abuse in hair specimens from poly-drug abusers. Copyright © 2013 Elsevier B.V. All rights reserved.

SATe-II: very fast and accurate simultaneous estimation of multiple sequence alignments and phylogenetic trees.

PubMed

Liu, Kevin; Warnow, Tandy J; Holder, Mark T; Nelesen, Serita M; Yu, Jiaye; Stamatakis, Alexandros P; Linder, C Randal

2012-01-01

Highly accurate estimation of phylogenetic trees for large data sets is difficult, in part because multiple sequence alignments must be accurate for phylogeny estimation methods to be accurate. Coestimation of alignments and trees has been attempted but currently only SATé estimates reasonably accurate trees and alignments for large data sets in practical time frames (Liu K., Raghavan S., Nelesen S., Linder C.R., Warnow T. 2009b. Rapid and accurate large-scale coestimation of sequence alignments and phylogenetic trees. Science. 324:1561-1564). Here, we present a modification to the original SATé algorithm that improves upon SATé (which we now call SATé-I) in terms of speed and of phylogenetic and alignment accuracy. SATé-II uses a different divide-and-conquer strategy than SATé-I and so produces smaller more closely related subsets than SATé-I; as a result, SATé-II produces more accurate alignments and trees, can analyze larger data sets, and runs more efficiently than SATé-I. Generally, SATé is a metamethod that takes an existing multiple sequence alignment method as an input parameter and boosts the quality of that alignment method. SATé-II-boosted alignment methods are significantly more accurate than their unboosted versions, and trees based upon these improved alignments are more accurate than trees based upon the original alignments. Because SATé-I used maximum likelihood (ML) methods that treat gaps as missing data to estimate trees and because we found a correlation between the quality of tree/alignment pairs and ML scores, we explored the degree to which SATé's performance depends on using ML with gaps treated as missing data to determine the best tree/alignment pair. We present two lines of evidence that using ML with gaps treated as missing data to optimize the alignment and tree produces very poor results. First, we show that the optimization problem where a set of unaligned DNA sequences is given and the output is the tree and alignment of those sequences that maximize likelihood under the Jukes-Cantor model is uninformative in the worst possible sense. For all inputs, all trees optimize the likelihood score. Second, we show that a greedy heuristic that uses GTR+Gamma ML to optimize the alignment and the tree can produce very poor alignments and trees. Therefore, the excellent performance of SATé-II and SATé-I is not because ML is used as an optimization criterion for choosing the best tree/alignment pair but rather due to the particular divide-and-conquer realignment techniques employed.

Crafty Corner.

ERIC Educational Resources Information Center

Naturescope, 1986

1986-01-01

Presents step-by-step procedures for two arts and crafts lessons that focus on mammals. Directions are offered for making mammal-shaped dough magnets and also for creating mammal note cards. Examples of each are illustrated. (ML)

[Evaluation of in vitro antimicrobial activity of cefazolin alone and in combination with cefmetazole or flomoxef using agar dilution method and disk diffusion method].

PubMed

Matsuo, K; Uete, T

1992-10-01

Antimicrobial activities of cefazolin (CEZ) against 251 strains of various clinical isolates obtained during 1989 and 1990 were determined using the Mueller-Hinton agar dilution method at an inoculum level 10(6) CFU/ml. The reliability of the disk susceptility test was also studied using Mueller-Hinton agar and various disks at inoculum levels of 10(3-4) CFU/cm2 in estimating approximate values of MICs. In addition, antimicrobial activities of CEZ and cefmetazole (CMZ) or flomoxef (FMOX) in combination were investigated against methicillin-sensitive and -resistant Staphylococcus aureus (MSSA and MRSA) using the checkerboard agar dilution MIC method and the disk diffusion test either with the disks contained CEZ, CMZ, and FMOX alone, or CEZ, and CMZ or FMOX in combination. In this study, the MICs of CEZ against S. aureus were distributed with the 3 peak values at 0.39 microgram/ml, 3.13 micrograms/ml and > 100 micrograms/ml. MICs against MSSA were 0.39 microgram/ml to 0.78 microgram/ml, whereas those against MRSA were greater than 0.78 microgram/ml. MICs against majority of strains of Enterococcus faecalis were 25 micrograms/ml. Over 90% of strains of Escherichia coli and Klebsiella pneumoniae were inhibited at the level of 3.13 micrograms/ml. About 60% of isolates of indole negative Proteus spp. were inhibited at the levels of less than 3.13 micrograms/ml and 100% at 6.25 micrograms/ml, but MICs against indole positive Proteus spp., Serratia spp. and Pseudomonas aeruginosa were over 100 micrograms/ml. The antimicrobial activities of CEZ against these clinical isolates were not significantly different compared to those reported about 15-20 years ago, except for S. aureus. Highly resistant strains of S. aureus to CEZ were more prevalent in this study. The inhibitory zones obtained with the disk test were compared with MICs. The results of CEZ disk susceptibility test with 30 micrograms disk (Showa) or 10 micrograms disk (prepared in this laboratory) were well correlated with MICs (r = -0.837 and -0.814, respectively), showing the reliavility of the disk method in estimating approximate values of MICs. In the 4 category classification system currently used in Japan, break points in MIC values proposed are () MIC < or = 3 micrograms/ml, (++) > 3-15 micrograms/ml, (+) > 15-60 micrograms/ml, (-) > 60 micrograms/ml. The results obtained with 30 micrograms disks showed false positive in 7.7% and false negative in 6.8% of the samples. The disk results with E. faecalis showed a higher ratio of false positive results.(ABSTRACT TRUNCATED AT 400 WORDS)

Development and validation of multivariate calibration methods for simultaneous estimation of Paracetamol, Enalapril maleate and hydrochlorothiazide in pharmaceutical dosage form

NASA Astrophysics Data System (ADS)

Singh, Veena D.; Daharwal, Sanjay J.

2017-01-01

Three multivariate calibration spectrophotometric methods were developed for simultaneous estimation of Paracetamol (PARA), Enalapril maleate (ENM) and Hydrochlorothiazide (HCTZ) in tablet dosage form; namely multi-linear regression calibration (MLRC), trilinear regression calibration method (TLRC) and classical least square (CLS) method. The selectivity of the proposed methods were studied by analyzing the laboratory prepared ternary mixture and successfully applied in their combined dosage form. The proposed methods were validated as per ICH guidelines and good accuracy; precision and specificity were confirmed within the concentration range of 5-35 μg mL- 1, 5-40 μg mL- 1 and 5-40 μg mL- 1of PARA, HCTZ and ENM, respectively. The results were statistically compared with reported HPLC method. Thus, the proposed methods can be effectively useful for the routine quality control analysis of these drugs in commercial tablet dosage form.

Diagnosis and Dosimetry of Exposure to Sulfur Mustard: Development of Standard Operating Procedures; Further Exploratory Research on Protein Adducts

DTIC Science & Technology

1999-01-01

Adducts 6. AUTHOR(S) Hendrick Benschop, Ph.D. 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION TNO Prins Maurits Laboratory...Mannheim, Germany); penicillin (Gist Brocades, Delft, The Netherlands); rabbit-anti-mouse-Ig-horse radish peroxidase (Dakopatts, Glostrup, Denmark); FITC...grown in RPMI1640-medium supplemented with 10% FCS, 1 mM sodium pyruvate, 1 mM glutamine, 100 U/ml penicillin , 0.1 mg/ml streptomycin and 50 mM B

Processing Method for Creating Ultra-Thin Lead Zirconate Titanate (PZT) Films Via Chemical Solution Deposition

DTIC Science & Technology

2008-12-01

n-propoxide and titanium isopropoxide , were measured with a graduated auto pipet and combined with 45 mL of 2-MOE in a 125 mL flask. The solution...nitrogen (N2). This anneal procedure was used to remove trapped hydrogen from the thin film. Following the anneal, a bi-layer of titanium (Ti) and...dioxide Ti titanium 10 NO. OF COPIES ORGANIZATION 1 ADMNSTR ELEC DEFNS TECHL INFO CTR ATTN DTIC OCP 8725 JOHN J KINGMAN RD STE

Determination of 6-mercaptopurine and azathioprine in plasma by high-performance liquid chromatography.

PubMed

Ding, T L; Benet, L Z

1979-07-21

Using 1-ml plasma samples, levels of 6-mercaptopurine (6MP) as low as 5 ng/ml and azathioprine (AZA) as low as 40 ng/ml can be detected using a high-performance liquid chromatography reversed-phase column procedure following extraction. Both compounds were stable in frozen plasma for seven weeks. AZA stability in blood was temperature dependent; the half-lives of AZA breakdown to 6MP at 37 degrees were 28 and 46 min in blood drawn from two rhesus monkeys. Plasma levels of 6MP were measured in a rhesus monkey following 6MP (1.47 mg/kg) and AZA (3 mg/kg) intravenous administration. 6MP levels were also measured in three renal transplant patients on daily 50- and 100-mg AZA doses. Peak levels (45-75 ng/ml) were reached within an hour and 6MP levels were detected for up to 7 h.

Revisiting the susceptibility testing of Mycobacterium tuberculosis to ethionamide in solid culture medium.

PubMed

Lakshmi, Rajagopalan; Ramachandran, Ranjani; Kumar, D Ravi; Sundar, A Syam; Radhika, G; Rahman, Fathima; Selvakumar, N; Kumar, Vanaja

2015-11-01

Increase in the isolation of drug resistant phenotypes of Mycobacterium tuberculosis necessitates accuracy in the testing methodology. Critical concentration defining resistance for ethionamide (ETO), needs re-evaluation in accordance with the current scenario. Thus, re-evaluation of conventional minimum inhibitory concentration (MIC) and proportion sensitivity testing (PST) methods for ETO was done to identify the ideal breakpoint concentration defining resistance. Isolates of M. tuberculosis (n=235) from new and treated patients were subjected to conventional MIC and PST methods for ETO following standard operating procedures. With breakpoint concentration set at 114 and 156 µg/ml, an increase in specificity was observed whereas sensitivity was high with 80 µg/ml as breakpoint concentration. Errors due to false resistant and susceptible isolates were least at 80 µg/ml concentration. Performance parameters at 80 µg/ml breakpoint concentration indicated significant association between PST and MIC methods.

Catheter drainage of pleural fluid collections and pneumothorax.

PubMed

Frendin, J; Obel, N

1997-06-01

A technique for virtually atraumatic placement of small size chest catheters for suction drainage of pleural effusions and pneumothorax in the dog and cat is described. Thirty-nine dogs and two cats were treated for pyothorax (10 cases), hydrothorax (eight), chylothorax (three), haemothorax (three), haemothorax/ pneumothorax (three) and pneumothorax (14). In all 41 cases, thin or viscous fluid and/or air were efficiently drained. The mean period of drainage was four days (range, 0.5 to 18 days). The average amount of fluid removed from each patient in 24 hours was 530 ml in pyothorax cases (range, 140 to 1100 ml) and 1300 ml in the other cases (range, 20 to 5000 ml). In 40 cases there were no complications related to the procedure. One dog with severe pleural adhesions was euthanased because of lung perforation and pneumothorax secondary to misplacement of the catheter.

Impact of novel techniques on minimally invasive adrenal surgery: trends and outcomes from a contemporary international large series in urology.

PubMed

Pavan, Nicola; Autorino, Riccardo; Lee, Hak; Porpiglia, Francesco; Sun, Yinghao; Greco, Francesco; Jeff Chueh, S; Han, Deok Hyun; Cindolo, Luca; Ferro, Matteo; Chen, Xiang; Branco, Anibal; Fornara, Paolo; Liao, Chun-Hou; Miyajima, Akira; Kyriazis, Iason; Puglisi, Marco; Fiori, Cristian; Yang, Bo; Fei, Guo; Altieri, Vincenzo; Jeong, Byong Chang; Berardinelli, Francesco; Schips, Luigi; De Cobelli, Ottavio; Chen, Zhi; Haber, Georges-Pascal; He, Yao; Oya, Mototsugu; Liatsikos, Evangelos; Brandao, Luis; Challacombe, Benjamin; Kaouk, Jihad; Darweesh, Ithaar

2016-10-01

To evaluate contemporary international trends in the implementation of minimally invasive adrenalectomy and to assess contemporary outcomes of different minimally invasive techniques performed at urologic centers worldwide. A retrospective multinational multicenter study of patients who underwent minimally invasive adrenalectomy from 2008 to 2013 at 14 urology institutions worldwide was included in the analysis. Cases were categorized based on the minimally invasive adrenalectomy technique: conventional laparoscopy (CL), robot-assisted laparoscopy (RAL), laparoendoscopic single-site surgery (LESS), and mini-laparoscopy (ML). The rates of the four treatment modalities were determined according to the year of surgery, and a regression analysis was performed for trends in all surgical modalities. Overall, a total of 737 adrenalectomies were performed across participating institutions and included in this analysis: 337 CL (46 % of cases), 57 ML (8 %), 263 LESS (36 %), and 80 RA (11 %). Overall, 204 (28 %) operations were performed with a retroperitoneal approach. The overall number of adrenalectomies increased from 2008 to 2013 (p = 0.05). A transperitoneal approach was preferred in all but the ML group (p < 0.001). European centers mostly adopted CL and ML techniques, whereas those from Asia and South America reported the highest rate in LESS procedures, and RAL was adopted to larger extent in the USA. LESS had the fastest increase in utilization at 6 %/year. The rate of RAL procedures increased at slower rates (2.2 %/year), similar to ML (1.7 %/year). Limitations of this study are the retrospective design and the lack of a cost analysis. Several minimally invasive surgical techniques for the management of adrenal masses are successfully implemented in urology institutions worldwide. CL and LESS seem to represent the most commonly adopted techniques, whereas ML and RAL are growing at a slower rate. All the MIS techniques can be safely and effectively performed for a variety of adrenal disease.

[Studies for analyzing prohibited ingredients such as estriol in cosmetics].

PubMed

Tokunaga, Hiroshi; Takeuchi, Orie; Uchino, Tadashi; Ando, Masanori

2004-01-01

Estriol (EO) is nominated as the prohibited ingredients in cosmetics in Japanese Pharmaceutical Affairs Act. So the analytical method using HPLC for EO was investigated. After placing 1.0 ml of EO solution at 50 microg/ml and 0.5 g of the lotion into a 10-ml volumetric flask, the methanol was added to make until that volume and this solution was used as the testing solution. Milky lotion was procedured as follows: After placing 1.0 ml of EO solution at 50 microg/ml and 0.5 g of the milky lotion into a 10-ml volumetric flask, the methanol was added to make until that volume. The suspending mixture was moved to a centrifuging tube with a cap. After centrifuging at 3000 rpm for 5 minutes, the supernatant was used as the testing solution. The testing solution of 20 microl was determined by HPLC using the ODS column (CAPCELL PAK C18 column, 4.6 x 250 mm), the mixture of water and acetonitrile (31:9) and the detection wavelength of 285 nm. The working curve from 1.0 to 6.0 microg/ml showed a linear line between the concentrations of EO and the peak area. There was no interference of peak of EO from the lotion and milky lotion.

Single center experience in selecting the laparoscopic Frey procedure for chronic pancreatitis.

PubMed

Tan, Chun-Lu; Zhang, Hao; Li, Ke-Zhou

2015-11-28

To share our experience regarding the laparoscopic Frey procedure for chronic pancreatitis (CP) and patient selection. All consecutive patients undergoing duodenum-preserving pancreatic head resection from July 2013 to July 2014 were reviewed and those undergoing the Frey procedure for CP were included in this study. Data on age, gender, body mass index (BMI), American Society of Anesthesiologists score, imaging findings, inflammatory index (white blood cells, interleukin (IL)-6, and C-reaction protein), visual analogue score score during hospitalization and outpatient visit, history of CP, operative time, estimated blood loss, and postoperative data (postoperative mortality and morbidity, postoperative length of hospital stay) were obtained for patients undergoing laparoscopic surgery. The open surgery cases in this study were analyzed for risk factors related to extensive bleeding, which was the major reason for conversion during the laparoscopic procedure. Age, gender, etiology, imaging findings, amylase level, complications due to pancreatitis, functional insufficiency, and history of CP were assessed in these patients. Nine laparoscopic and 37 open Frey procedures were analyzed. Of the 46 patients, 39 were male (85%) and seven were female (16%). The etiology of CP was alcohol in 32 patients (70%) and idiopathic in 14 patients (30%). Stones were found in 38 patients (83%). An inflammatory mass was found in five patients (11%). The time from diagnosis of CP to the Frey procedure was 39 ± 19 (9-85) mo. The BMI of patients in the laparoscopic group was 20.4 ± 1.7 (17.8-22.4) kg/m(2) and was 20.6 ± 2.9 (15.4-27.7) kg/m(2) in the open group. All patients required analgesic medication for abdominal pain. Frequent acute pancreatitis or severe abdominal pain due to acute exacerbation occurred in 20 patients (43%). Pre-operative complications due to pancreatitis were observed in 18 patients (39%). Pancreatic functional insufficiency was observed in 14 patients (30%). Two laparoscopic patients (2/9) were converted. In seven successful laparoscopic cases, the mean operative time was 323 ± 29 (290-370) min. Estimated intra-operative blood loss was 57 ± 14 (40-80) mL. One patient had a postoperative complication, and no mortality was observed. Postoperative hospital stay was 7 ± 2 (5-11) d. Multiple linear regression analysis of 37 open Frey procedures showed that an inflammatory mass (P < 0.001) and acute exacerbation (P < 0.001) were risk factors for intra-operative blood loss. The laparoscopic Frey procedure for CP is feasible but only suitable in carefully selected patients.

Single center experience in selecting the laparoscopic Frey procedure for chronic pancreatitis

PubMed Central

Tan, Chun-Lu; Zhang, Hao; Li, Ke-Zhou

2015-01-01

AIM: To share our experience regarding the laparoscopic Frey procedure for chronic pancreatitis (CP) and patient selection. METHODS: All consecutive patients undergoing duodenum-preserving pancreatic head resection from July 2013 to July 2014 were reviewed and those undergoing the Frey procedure for CP were included in this study. Data on age, gender, body mass index (BMI), American Society of Anesthesiologists score, imaging findings, inflammatory index (white blood cells, interleukin (IL)-6, and C-reaction protein), visual analogue score score during hospitalization and outpatient visit, history of CP, operative time, estimated blood loss, and postoperative data (postoperative mortality and morbidity, postoperative length of hospital stay) were obtained for patients undergoing laparoscopic surgery. The open surgery cases in this study were analyzed for risk factors related to extensive bleeding, which was the major reason for conversion during the laparoscopic procedure. Age, gender, etiology, imaging findings, amylase level, complications due to pancreatitis, functional insufficiency, and history of CP were assessed in these patients. RESULTS: Nine laparoscopic and 37 open Frey procedures were analyzed. Of the 46 patients, 39 were male (85%) and seven were female (16%). The etiology of CP was alcohol in 32 patients (70%) and idiopathic in 14 patients (30%). Stones were found in 38 patients (83%). An inflammatory mass was found in five patients (11%). The time from diagnosis of CP to the Frey procedure was 39 ± 19 (9-85) mo. The BMI of patients in the laparoscopic group was 20.4 ± 1.7 (17.8-22.4) kg/m2 and was 20.6 ± 2.9 (15.4-27.7) kg/m2 in the open group. All patients required analgesic medication for abdominal pain. Frequent acute pancreatitis or severe abdominal pain due to acute exacerbation occurred in 20 patients (43%). Pre-operative complications due to pancreatitis were observed in 18 patients (39%). Pancreatic functional insufficiency was observed in 14 patients (30%). Two laparoscopic patients (2/9) were converted. In seven successful laparoscopic cases, the mean operative time was 323 ± 29 (290-370) min. Estimated intra-operative blood loss was 57 ± 14 (40-80) mL. One patient had a postoperative complication, and no mortality was observed. Postoperative hospital stay was 7 ± 2 (5-11) d. Multiple linear regression analysis of 37 open Frey procedures showed that an inflammatory mass (P < 0.001) and acute exacerbation (P < 0.001) were risk factors for intra-operative blood loss. CONCLUSION: The laparoscopic Frey procedure for CP is feasible but only suitable in carefully selected patients. PMID:26640341

Clinical practice guidelines on menorrhagia: management of abnormal uterine bleeding before menopause.

PubMed

Marret, H; Fauconnier, A; Chabbert-Buffet, N; Cravello, L; Golfier, F; Gondry, J; Agostini, A; Bazot, M; Brailly-Tabard, S; Brun, J-L; De Raucourt, E; Gervaise, A; Gompel, A; Graesslin, O; Huchon, C; Lucot, J-P; Plu-Bureau, G; Roman, H; Fernandez, H

2010-10-01

Normal menstrual periods last 3-6 days and involve blood loss of up to 80ml. Menorrhagia is defined as menstrual periods lasting more than 7 days and/or involving blood loss greater than 80ml. The prevalence of abnormal uterine bleeding (AUB) is estimated at 11-13% in the general population and increases with age, reaching 24% in those aged 36-40 years. A blood count for red cells+platelets to test for anemia is recommended on a first-line basis for women consulting for AUB whose history and/or bleeding score justify it. A pregnancy test by an hCG assay should be ordered. A speculum examination and Pap smear, according to the French High Health Authority guidelines should be performed early on to rule out any cervical disease. Pelvic ultrasound, both abdominal (suprapubic) and transvaginal, is recommended as a first-line procedure for the etiological diagnosis of AUB. Hysteroscopy or hysterosonography can be suggested as a second-line procedure. MRI is not recommended as a first-line procedure. In idiopathic AUB, the first-line treatment is medical, with efficacy ranked as follows: levonorgestrel IUD, tranexamic acid, oral contraceptives, either estrogens and progestins or synthetic progestins only, 21 days a month, or NSAIDs. When hormone treatment is contraindicated or immediate pregnancy is desired, tranexamic acid is indicated. Iron must be included for patients with iron-deficiency anemia. For women who do not wish to become pregnant in the future and who have idiopathic AUB, the long-term efficacy of conservative surgical treatment is greater than that of oral medical treatment. Placement of a levonorgestrel IUD (or administration of tranexamic acid by default) is recommended for women with idiopathic AUB. If this fails, a conservative surgical technique must be proposed; the choices include second-generation endometrial ablation techniques (thermal balloon, microwave, radiofrequency), or, if necessary, first-generation techniques (endometrectomy, roller-ball). A first-line hysterectomy is not recommended in this context. Should a hysterectomy be selected for functional bleeding, it should be performed by the vaginal or laparoscopic routes. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Introduction of a new laser-scalpel for partial kidney resection based on 1.94 micrometer fiber laser system: initial in vivo-data

NASA Astrophysics Data System (ADS)

Tedsen, Sönke; Theisen-Kunde, Dirk; Doehn, Christian; Kausch, Ingo; Jocham, Dieter

2009-02-01

The technique of nephron sparing surgery has matured significantly over the past decade and is emerging as an oncologically sound procedure for the management of renal tumors. Methods of tumor excision as well as parenchymal reconstruction in a hemostaticallly controlled field have evolved to make this procedure safer. In an attempt to find an improoved hemostatic cutting instrument we developed a 1.94 micrometer Laser-Scalpel system in a porcine model. We evaluated data for partial porcine kidney resection performed by a 1.94 micrometer Laser-Scalpel and compared the data to those of a standard HF- (High- Frequency) dissection device. In 12 pigs general anesthesia and a median laparotomy was performed to expose both kidneys. In each pig one kidney was partially resected with the Laser-Scalpel and the other side with the HF-dissection device. The first 6 pigs were euthanized immediately after the procedure. The following 6 pigs were allowed to recover and underwent 2-3 weeks later euthanasia. The final evaluation data included total resection time, blood loss, mass of dissected tissue, total ischemic time and histological examination. Mean resected kidney tissue mass was 4.75 g with the laser system and 5.57 g for the HF-dissector, respectively. Mean estimated blood loss was 22 ml for the Laser- Scalpel and 78.2 ml for the HF-dissection device. Resection time was 9.45 min for the Laser-scalpel compared to 10.16 min. No complications, specifically no postoperative bleeding, occured in any of the animals. Histological evaluation with H&E staining showed a carbonized zone of about 0.57 mm directly at the dissected edge followed by a thermal damaged zone of about 1.25 mm in width. Thereafter healthy tissue was found in all histological samples. Partial kidney resection was easily and fast performed by the use of a 1.94 micrometer Laser-Scalpel system. Hemostasis was highly sufficient, so blood loss was minimal compared to conventional HF-dissection device. Therefore the 1.94 micrometer Laser-Scalpel system is a very promising dissection device for urological surgery.

Solid-phase extraction followed by liquid chromatography quadrupole time-of-flight tandem mass spectrometry for the selective determination of fungicides in wine samples.

PubMed

Fontana, A R; Rodríguez, I; Ramil, M; Altamirano, J C; Cela, R

2011-04-22

In this work, a reliable and selective procedure for the determination of thirteen fungicides in red and white wine samples is proposed. Solid-phase extraction (SPE) and liquid chromatography (LC) tandem mass spectrometry (MS/MS), based on a hybrid quadrupole time-of-flight (QTOF) system, were used as sample preparation and determination techniques, respectively. Extraction and purification of target analytes was carried out simultaneously by using a reversed-phase Oasis HLB (200mg) SPE cartridge combined with acetonitrile as elution solvent. Fungicides were determined operating the electrospray source in the positive ionization mode, with MS/MS conditions adjusted to obtain at least two intense product ions per compound, or registering two transitions per species when a single product was noticed. High selective MS/MS chromatograms were extracted using a mass window of 20 ppms for each product ion. Considering external calibration as quantification technique, the overall recoveries (accuracy) of the procedure ranged between 81% and 114% for red and white wine samples (10-20 mL), spiked at different concentrations between 5 and 100 ng mL(-1). Relative standard deviations of the above data stayed below 12% and the limits of quantification (LOQs) of the method, calculated for 10 mL of wine, varied between 0.1 ng mL(-1) for cyprodinil (CYP) and 0.7 ng mL(-1) for myclobutanil (MYC). The optimized method was applied to seventeen commercial wines produced in Spain and obtained from local supermarkets. Nine fungicides were determined, at levels above the LOQs of the method, in the above samples. The maximum concentrations and the highest occurrence frequencies corresponded to metalaxyl (MET) and iprovalicarb (IPR). Copyright © 2011 Elsevier B.V. All rights reserved.

Fully automated analytical procedure for propofol determination by sequential injection technique with spectrophotometric and fluorimetric detections.

PubMed

Šrámková, Ivana; Amorim, Célia G; Sklenářová, Hana; Montenegro, Maria C B M; Horstkotte, Burkhard; Araújo, Alberto N; Solich, Petr

2014-01-01

In this work, an application of an enzymatic reaction for the determination of the highly hydrophobic drug propofol in emulsion dosage form is presented. Emulsions represent a complex and therefore challenging matrix for analysis. Ethanol was used for breakage of a lipid emulsion, which enabled optical detection. A fully automated method based on Sequential Injection Analysis was developed, allowing propofol determination without the requirement of tedious sample pre-treatment. The method was based on spectrophotometric detection after the enzymatic oxidation catalysed by horseradish peroxidase and subsequent coupling with 4-aminoantipyrine leading to a coloured product with an absorbance maximum at 485 nm. This procedure was compared with a simple fluorimetric method, which was based on the direct selective fluorescence emission of propofol in ethanol at 347 nm. Both methods provide comparable validation parameters with linear working ranges of 0.005-0.100 mg mL(-1) and 0.004-0.243 mg mL(-1) for the spectrophotometric and fluorimetric methods, respectively. The detection and quantitation limits achieved with the spectrophotometric method were 0.0016 and 0.0053 mg mL(-1), respectively. The fluorimetric method provided the detection limit of 0.0013 mg mL(-1) and limit of quantitation of 0.0043 mg mL(-1). The RSD did not exceed 5% and 2% (n=10), correspondingly. A sample throughput of approx. 14 h(-1) for the spectrophotometric and 68 h(-1) for the fluorimetric detection was achieved. Both methods proved to be suitable for the determination of propofol in pharmaceutical formulation with average recovery values of 98.1 and 98.5%. © 2013 Elsevier B.V. All rights reserved.

[Perioperative fluid therapy in perforated ulcers].

PubMed

Bjerre, Catherine Collin; Holte, Kathrine

2009-04-27

Surgery for perforated ulcers is one of the most common emergency surgical procedures. Approximately 400 procedures are performed each year in Denmark and mortality is high, reaching close to 30% at 30 days postoperatively. The importance of perioperative fluid administration during the perioperative course remains unclear. The purpose of this study is to describe the perioperative fluid management in these patients in order to identify problem areas (if any) and to create a basis on which future trials on fluid management in this patient group may be designed. Retrospective survey of 45 consecutive patients operated for perforated ulcers over a 3-year period between 1 January 2003 and 31 December 2005 in the surgical department of a university hospital. Data that would permit rational fluid therapy are not being collected on a regular basis. Fluid balance charts were kept for 42 patients on the day of operation (89%), for 29 patients on the first post-operative day (61%), for 17 patients on the second post-operative day (36%) and for 12 patients (25%) on the third post-operative day. No patients were weighed for assessment of fluid status. Perioperative fluid administration varied extensively, with fluid balance on the day of surgery ranging from -45 to 8,030 ml (median 2688 ml) and a cumulated fluid balance of 7,2 litres (1,875-14,565 ml) three days postoperatively. Generally, patients had no fluid administered prior to surgery (median 0 ml, applying to 41 patients (87%) range 0-4,500 ml). Both the preoperative fluid management and the postoperative monitoring of the fluid balance are suboptimal and should be optimized. Individualized (goal-directed) fluid administration aiming at optimizing the oxygen supply to the peripheral tissues is warranted and is recommended to high-risk emergency surgery patients.

Determination of lead and nickel in environmental samples by flame atomic absorption spectrometry after column solid-phase extraction on Ambersorb-572 with EDTA.

PubMed

Baytak, Sitki; Türker, A Rehber

2006-02-28

Lead and nickel were preconcentrated as their ethylenediaminetetraacedic acid (EDTA) complexes from aqueous sample solutions using a column containing Ambersorb-572 and determined by flame atomic absorption spectrometry (FAAS). pH values, amount of solid phase, elution solution and flow rate of sample solution have been optimized in order to obtain quantitative recovery of the analytes. The effect of interfering ions on the recovery of the analytes has also been investigated. The recoveries of Pb and Ni under the optimum conditions were 99 +/- 2 and 97 +/- 3%, respectively, at 95% confidence level. Seventy-five-fold (using 750 mL of sample solution and 10 mL of eluent) and 50-fold (using 500 mL of sample solution and 10 mL of eluent) preconcentration was obtained for Pb and Ni, respectively. Time of analysis is about 4.5 h (for obtaining enrichment factor of 75). By applying these enrichment factors, the analytical detection limits of Pb and Ni were found as 3.65 and 1.42 ng mL(-1), respectively. The capacity of the sorbent was found as 0.17 and 0.21 mmol g(-1) for Pb and Ni, respectively. The interferences of some cations, such as Mn2+, Co2+, Fe3+, Al3+, Zn2+, Cd2+, Ca2+, Mg2+, K+ and Na+ usually present in water samples were also studied. This procedure was applied to the determination of lead and nickel in parsley, green onion, sea water and waste water samples. The accuracy of the procedure was checked by determining Pb and Ni in standard reference tea leaves sample (GBW-07605). The results demonstrated good agreement with the certified values.

Science Notes.

ERIC Educational Resources Information Center

School Science Review, 1985

1985-01-01

Presents 23 experiments, activities, field projects and computer programs in the biological and physical sciences. Instructional procedures, experimental designs, materials, and background information are suggested. Topics include fluid mechanics, electricity, crystals, arthropods, limpets, acid neutralization, and software evaluation. (ML)

Monitoring Air Quality with Leaf Yeasts.

ERIC Educational Resources Information Center

Richardson, D. H. S.; And Others

1985-01-01

Proposes that leaf yeast serve as quick, inexpensive, and effective techniques for monitoring air quality. Outlines procedures and provides suggestions for data analysis. Includes results from sample school groups who employed this technique. (ML)

Preliminary measurement of gas concentrations of perfluropropane using an analytical weighing balance.

PubMed

Clarkson, Douglas McG; Manna, Avinish; Hero, Mark

2014-02-01

We describe the use of an analytical weighing balance of measurement accuracy 0.00001g for determination of concentrations of perfluropropane (C3F8) gas used in ophthalmic surgical vitrectomy procedures. A range of test eyes corresponding to an eye volume of 6.1ml were constructed using 27 gauge needle exit ducts and separately 20 gauge (straight) and 23 gauge (angled) entrance ports. This method allowed determination of concentration levels in the sample preparation syringe and also levels in test eyes. It was determined that a key factor influencing gas concentrations accuracy related to the method of gas fill and the value of dead space of the gas preparation/delivery system and with a significant contribution arising from the use of the particle filter. The weighing balance technique was identified as an appropriate technique for estimation of gas concentrations. Copyright © 2013 IPEM. Published by Elsevier Ltd. All rights reserved.

A modified catheterization procedure to reduce bladder damage when collecting urine samples from Holstein cows.

PubMed

Tamura, Tetsuo; Nakamura, Hiroshi; Sato, Say; Seki, Makoto; Nishiki, Hideto

2014-06-01

This study proposed a modified procedure, using a small balloon catheter (SB catheter, 45 ml), for reducing bladder damage in cows. Holstein cows and the following catheters were prepared: smaller balloon catheter (XSB catheter; 30 ml), SB catheter and standard balloon catheter (NB catheter; 70 ml, as the commonly used, standard size). In experiment 1, each cow was catheterized. The occurrence of catheter-associated hematuria (greater than 50 RBC/HPF) was lower in the SB catheter group (0.0%, n=7) than in the NB catheter group (71.4%, n=7; P<0.05). In experiment 2, general veterinary parameters, urine pH, body temperature and blood values in cows were not affected before or after insertion of SB catheters (n=6). The incidence of urinary tract infection (UTI) was 3.0% per catheterized day (n=22). In experiment 3, feeding profiles, daily excretion of urinary nitrogen (P<0.05) and rate from nitrogen intake in urine (P<0.01), were higher with use of the SB catheter (n=13) than with the use of the vulva urine cup (n=18), indicating that using the SB catheter can provide accurate nutritional data. From this study, we concluded that when using an SB catheter, the following results occur; reduction in bladder damage without any veterinary risks and accuracy in regard to feeding parameters, suggesting this modified procedure using an SB catheter is a useful means of daily urine collection.

A Modified Catheterization Procedure to Reduce Bladder Damage when Collecting Urine Samples from Holstein Cows

PubMed Central

TAMURA, Tetsuo; NAKAMURA, Hiroshi; SATO, Say; SEKI, Makoto; NISHIKI, Hideto

2014-01-01

ABSTRACT This study proposed a modified procedure, using a small balloon catheter (SB catheter, 45 ml), for reducing bladder damage in cows. Holstein cows and the following catheters were prepared: smaller balloon catheter (XSB catheter; 30 ml), SB catheter and standard balloon catheter (NB catheter; 70 ml, as the commonly used, standard size). In experiment 1, each cow was catheterized. The occurrence of catheter-associated hematuria (greater than 50 RBC/HPF) was lower in the SB catheter group (0.0%, n=7) than in the NB catheter group (71.4%, n=7; P<0.05). In experiment 2, general veterinary parameters, urine pH, body temperature and blood values in cows were not affected before or after insertion of SB catheters (n=6). The incidence of urinary tract infection (UTI) was 3.0% per catheterized day (n=22). In experiment 3, feeding profiles, daily excretion of urinary nitrogen (P<0.05) and rate from nitrogen intake in urine (P<0.01), were higher with use of the SB catheter (n=13) than with the use of the vulva urine cup (n=18), indicating that using the SB catheter can provide accurate nutritional data. From this study, we concluded that when using an SB catheter, the following results occur; reduction in bladder damage without any veterinary risks and accuracy in regard to feeding parameters, suggesting this modified procedure using an SB catheter is a useful means of daily urine collection. PMID:24561376

[Studies for analyzing the prohibited ingredients such as cyproheptadine hydrochloride in cosmetics].

PubMed

Tokunaga, Hiroshi; Uchino, Tadashi

2005-01-01

Cyproheptadine hydrochloride (CH) is nominated as the prohibited ingredients in cosmetics in Japanese Pharmaceutical Affairs Act. So the analytical method for CH was investigated by HPLC. The lotion or milky lotion of 0.5 g was put into a 10-ml volumetric flask. After adding 1.0ml of CH solution at 50 microg/ml into the volumetric flask, the mixture was made up to 10ml with methanol as the test solution. Creams were procedured as follows; 0.5 g of cream was put into a 10-ml volumetric flask. After adding 1.0 ml of tetrahydrofuran into the volumetric flask, the mixture was stirred for several minutes and the ingredients of the creams were dissolved. After adding 1.0 ml of CH solution at 50 microg/ml into the volumetric flask, the mixture was made up to 10ml with methanol. This mixture was transferred to a centrifuging tube with a cap and then the tube was centrifuged for 5 minutes at 3000 rpm. The supernatant was used as the test solution. The test solution of 20 microl was analyzed by HPLC using the ODS column (CAPCELL PAK C18 column, 4.6 x 250 mm), the mixture of 1% acetic acid with 10 mmol/l sodium octanesulfonate and acetonitrile (11:9) and the detection wavelength of 286 nm. The working curve from 0.5 to 6.0 microg/ml showed a linear line between the concentrations of CH and the peak areas. There was no interference of peak of CH with the ingredients such as methylparaben, ethylparaben in the lotions, milky lotion and creams.

[Antimycoplasmal activities of ofloxacin and commonly used antimicrobial agents on Mycoplasma gallisepticum].

PubMed

Takahashi, I; Yoshida, T

1989-05-01

In vitro activities of ofloxacin (OFLX), a new quinolone derivative, against 29 strains of Mycoplasma gallisepticum was compared with those of 4 commonly used antimicrobial agents, doxycycline (DOXY), tylosin (TS), spectinomycin (SPCM) and thiamphenicol (TP). Antimycoplasmal activities of the drugs were evaluated on the MIC (final MIC) and MPC (minimum mycoplasmacidal concentration) values which were determined by a broth dilution procedure. The following results were obtained. 1. The MIC90s of OFLX and DOXY were both 0.20 micrograms/ml. The MICs of TS were distributed through a wide range (less than or equal to 0.006 - 0.78 micrograms/ml), and its MIC90 was 0.78 micrograms/ml. Of 29 M. gallisepticum strains, 27.6% were recognized as TS-resistant. The MIC90 values of SPCM and TP were 1.56 micrograms/ml and 3.13 micrograms/ml, respectively. The MIC90 of OFLX was equal to that of DOXY and 4- to 16-fold smaller than the values of the other 3 antibiotics. 2. The MPC of OFLX was the lowest among the antibiotics tested, its MPC90 value was 0.39 micrograms/ml and was followed by DOXY (1.56 micrograms/ml). The MPCs of TS were distributed in a wide range (0.012 - 3.13 micrograms/ml), and its MPC90 was 3.13 micrograms/ml. The MPC90 values of SPCM and TP were both 6.25 micrograms/ml. Therefore, the mycoplasmacidal activity of OFLX evaluated with MPC90 values was 4- to 16-fold greater than those of the other 4 antibiotics.

Influence of infusion volume on the ocular hemodynamic effects of peribulbar anesthesia.

PubMed

Lung, Solveig; Luksch, Alexandra; Weigert, Günther; Georgopoulos, Michael; Menapace, Rupert; Polska, Elzbieta; Garhofer, Gerhard; Findl, Oliver; Schmetterer, Leopold

2006-09-01

To test the hypothesis that ocular blood-flow response to peribulbar anesthesia can be reduced by using a smaller volume of anesthetic mixture. Departments of Ophthalmology and Clinical Pharmacology, Medical University of Vienna, Vienna, Austria. Twenty patients scheduled for bilateral age-related cataract surgery were enrolled in a prospective randomized balanced observer-masked crossover study. Two study days with a 2 mL injection volume or 5 mL injection volume used for peribulbar anesthesia were scheduled. On 1 study day, patients received the 1-dose regimen and on the other study day, when the contralateral eye had surgery, patients received the other injection volume. On both study days, the anesthetic mixture consisted of an equal amount of lidocaine, bupivacaine, and hyaluronidase independently of the injection volume. Intraocular pressure (IOP), blood pressure, and pulse rate were measured noninvasively. Ocular fundus pulsation amplitude (FPA) and peak systolic and end diastolic flow velocities in the central retinal artery were measured with laser interferometry and color Doppler imaging, respectively. The results were recorded as means +/- SD. Peribulbar anesthesia increased IOP and reduced FPA and flow velocities in the central retinal artery. The effects on IOP (5 mL, 35.1% +/- 16.0%; 2 mL, 14.1% +/- 14.1%; P<.001) and ocular hemodynamic parameters (FPA: 5 mL, -17.5% +/- 7.8%/2 mL, -7.3% +/- 7.2%, P<.001; peak systolic velocity: 5 mL, -19.5% +/- 10.7%/2 mL, -10.6% +/- 9.8%, P = .013; end diastolic velocity: 5 mL, -16.7% +/- 6.2%/2 mL, -8.4% +/- 7.3%, P = .005) were more pronounced with the 5 mL injection volume than with the 2 mL injection volume. An injection volume of 2 mL instead of 5 mL reduced the ocular blood-flow response to peribulbar anesthesia. This procedure may be used in patients with ocular vascular disease to reduce the incidence of anesthesia-induced ischemia and loss of vision.

High performance liquid chromatographic method for the determination of cetirizine and ambroxol in human plasma and urine--a boxcar approach.

PubMed

Dharuman, J; Vasudhevan, M; Ajithlal, T

2011-09-01

A column switching high performance liquid chromatographic method with estimable sensitivity and accuracy was developed for the determination of cetirizine and ambroxol in human plasma using nebivolol as the internal standard. Plasma samples were prepared by liquid-liquid extraction in methylene chloride and a mixture of diethylether (80:20, v/v). The extracted samples were injected into a multifunctional clean-up column Supelcosil LCABZ (50 mm × 4.6 mm, 5 μm particle size) using mobile phase 1 comprising acetonitrile-phosphate buffer (pH 3.5; 20 mM) (20:80, v/v). The eluate of cetirizine and ambroxol were separated to an analytical Kromasil C(8) micro bore column (50 mm × 0.3 mm, 5 μm particle size) via a column switching device. A Kromasil C(18) analytical column (250 mm × 2.1 mm, 5 μm particle size) was used as a separation column. Mobile phase 2 consisting acetonitrile-triethylamine (0.5%) in phosphate buffer (pH 3.5; 20mM) (55:45, v/v) was used for the compound elution. The eluents were detected at 230 nm with photodiode array detector. An aliquot of 150 μl of plasma sample was introduced into the pretreatment column via the auto sampler using mobile phase 1 at a flow rate of 0.5 ml/min, column switching valve being positioned at A. The pretreatment column retained cetirizine, ambroxol and nebivolol (IS) in the column leaving the residual proteins of plasma eluted in void volume and drained out. The switching valve was shifted to position B at 7.5 min. Cetirizine, ambroxol and IS were eluted from the pretreatment column between 7. 5 and 11.5 min and introduced to the concentration column. Finally, cetirizine, ambroxol and IS were introduced to the separation column by switching valve using mobile phase 2 at a flow rate of 0.4 ml/min. During the analysis the pretreatment column was washed for the next analysis and resume to the position A. The total run time was 25 min for a sample. The procedure was repeated for urine analysis also. The method was linear from 2 to 450 ng/ml and 7-300 ng/ml for cetirizine and ambroxol respectively in plasma and 1-500 ng/ml and 5-400 ng/ml, respectively for cetirizine and ambroxol in urine. Intra-day and inter-day precision of cetirizine and ambroxol was below 15% in terms of coefficient of variation and accuracy of cetirizine and ambroxol was ranged from 94 to 101.6% and 91.1 to 100.2%, respectively. The method demonstrated high sensitivity and selectivity and therefore, applied to evaluate pharmacokinetics of cetirizine and ambroxol in healthy human volunteer after a single oral administration. Urine samples obtained from healthy human volunteers and clinical subjects with renal impairment have also been analyzed by the method to compare the elimination pattern. The method was precise and accurate for the estimation of cetirizine and ambroxol both in blood and in urine. Copyright © 2011 Elsevier B.V. All rights reserved.

40 CFR 98.435 - Procedures for estimating missing data.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 21 2011-07-01 2011-07-01 false Procedures for estimating missing data... Gases Contained in Pre-Charged Equipment or Closed-Cell Foams § 98.435 Procedures for estimating missing data. Procedures for estimating missing data are not provided for importers and exporters of...

40 CFR 98.435 - Procedures for estimating missing data.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Procedures for estimating missing data... Gases Contained in Pre-Charged Equipment or Closed-Cell Foams § 98.435 Procedures for estimating missing data. Procedures for estimating missing data are not provided for importers and exporters of...

40 CFR 98.435 - Procedures for estimating missing data.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Procedures for estimating missing data... Gases Contained in Pre-Charged Equipment or Closed-Cell Foams § 98.435 Procedures for estimating missing data. Procedures for estimating missing data are not provided for importers and exporters of...

40 CFR 98.435 - Procedures for estimating missing data.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 22 2012-07-01 2012-07-01 false Procedures for estimating missing data... Gases Contained in Pre-Charged Equipment or Closed-Cell Foams § 98.435 Procedures for estimating missing data. Procedures for estimating missing data are not provided for importers and exporters of...

A new modified CKD-EPI equation for Chinese patients with type 2 diabetes.

PubMed

Liu, Xun; Gan, Xiaoliang; Chen, Jinxia; Lv, Linsheng; Li, Ming; Lou, Tanqi

2014-01-01

To improve the performance of glomerular filtration rate (GFR) estimating equation in Chinese type 2 diabetic patients by modification of the CKD-EPI equation. A total of 1196 subjects were enrolled. Measured GFR was calibrated to the dual plasma sample 99mTc-DTPA-GFR. GFRs estimated by the re-expressed 4-variable MDRD equation, the CKD-EPI equation and the Asian modified CKD-EPI equation were compared in 351 diabetic/non-diabetic pairs. And a new modified CKD-EPI equation was reconstructed in a total of 589 type 2 diabetic patients. In terms of both precision and accuracy, GFR estimating equations all achieved better results in the non-diabetic cohort comparing with those in the type 2 diabetic cohort (30% accuracy, P≤0.01 for all comparisons). In the validation data set, the new modified equation showed less bias (median difference, 2.3 ml/min/1.73 m2 for the new modified equation vs. ranged from -3.8 to -7.9 ml/min/1.73 m2 for the other 3 equations [P<0.001 for all comparisons]), as was precision (IQR of the difference, 24.5 ml/min/1.73 m2 vs. ranged from 27.3 to 30.7 ml/min/1.73 m2), leading to a greater accuracy (30% accuracy, 71.4% vs. 55.2% for the re-expressed 4 variable MDRD equation and 61.0% for the Asian modified CKD-EPI equation [P = 0.001 and P = 0.02]). A new modified CKD-EPI equation for type 2 diabetic patients was developed and validated. The new modified equation improves the performance of GFR estimation.

Comparing models for perfluorooctanoic acid pharmacokinetics using Bayesian analysis.

PubMed

Wambaugh, John F; Barton, Hugh A; Setzer, R Woodrow

2008-12-01

Selecting the appropriate pharmacokinetic (PK) model given the available data is investigated for perfluorooctanoic acid (PFOA), which has been widely analyzed with an empirical, one-compartment model. This research examined the results of experiments [Kemper R. A., DuPont Haskell Laboratories, USEPA Administrative Record AR-226.1499 (2003)] that administered single oral or iv doses of PFOA to adult male and female rats. PFOA concentration was observed over time; in plasma for some animals and in fecal and urinary excretion for others. There were four rats per dose group, for a total of 36 males and 36 females. Assuming that the PK parameters for each individual within a gender were drawn from the same, biologically varying population, plasma and excretion data were jointly analyzed using a hierarchical framework to separate uncertainty due to measurement error from actual biological variability. Bayesian analysis using Markov Chain Monte Carlo (MCMC) provides tools to perform such an analysis as well as quantitative diagnostics to evaluate and discriminate between models. Starting from a one-compartment PK model with separate clearances to urine and feces, the model was incrementally expanded using Bayesian measures to assess if the expansion was supported by the data. PFOA excretion is sexually dimorphic in rats; male rats have bi-phasic elimination that is roughly 40 times slower than that of the females, which appear to have a single elimination phase. The male and female data were analyzed separately, keeping only the parameters describing the measurement process in common. For male rats, including excretion data initially decreased certainty in the one-compartment parameter estimates compared to an analysis using plasma data only. Allowing a third, unspecified clearance improved agreement and increased certainty when all the data was used, however a significant amount of eliminated PFOA was estimated to be missing from the excretion data. Adding an additional PK compartment reduced the unaccounted-for elimination to amounts comparable to the cage wash. For both sexes, an MCMC estimate of the appropriateness of a model for a given data type, the Deviance Information Criterion, indicated that this two-compartment model was better suited to describing PFOA PK. The median estimate was 142.1 +/- 37.6 ml/kg for the volume of the primary compartment and 1.24 +/- 1.1 ml/kg/h for the clearances of male rats and 166.4 +/- 46.8 ml/kg and 30.3 +/- 13.2 ml/kg/h, respectively for female rats. The estimates for the second compartment differed greatly with gender-volume 311.8 +/- 453.9 ml/kg with clearance 3.2 +/- 6.2 for males and 1400 +/- 2507.5 ml/kg and 4.3 +/- 2.2 ml/kg/h for females. The median estimated clearance was 12 +/- 6% to feces and 85 +/- 7% to urine for male rats and 8 +/- 6% and 77 +/- 9% for female rats. We conclude that the available data may support more models for PFOA PK beyond two-compartments and that the methods employed here will be generally useful for more complicated, including PBPK, models.

Determination of Stress-Corrosion Cracking in Aluminum-Lithium Alloy ML377

NASA Technical Reports Server (NTRS)

Valek, Bryan C.

1995-01-01

The use of aluminum-lithium alloys for aerospace applications is currently being studied at NASA Langley Research Center's Metallic Materials Branch. The alloys in question will operate under stress in a corrosive environment. These conditions are ideal for the phenomena of Stress-Corrosion Cracking (SCC) to occur. The test procedure for SCC calls for alternate immersion and breaking load tests. These tests were optimized for the lab equipment and materials available in the Light Alloy lab. Al-Li alloy ML377 specimens were then subjected to alternate immersion and breaking load tests to determine residual strength and resistance to SCC. Corrosion morphology and microstructure were examined under magnification. Data shows that ML377 is highly resistant to stress-corrosion cracking.

Oxidation of benzyl alcohol by K2FeO4 to benzaldehyde over zeolites

NASA Astrophysics Data System (ADS)

Wang, Yuan-Yuan; Song, Hua; Song, Hua-Lin; Jin, Zai-Shun

2016-10-01

A novel and green procedure for benzaldehyde synthesis by potassium ferrate oxidation of benzyl alcohol employing zeolite catalysts was studied. The prepared oxidant was characterized by SEM and XRD. The catalytic activity of various solid catalysts was studied using benzyl alcohol as a model compound. USY was found to be a very efficient catalyst for this particular oxidation process. Benzaldehyde yields up to 96.0% could be obtained at the following optimal conditions: 0.2 mL of benzyl alcohol, 4 mmol of K2FeO4, 0.5 g of USY zeolite; 20 mL of cyclohexene, 0.3 mL of acetic acid (36 wt %), 30°C temperature, 4 h reaction time.

Estimating the benefits of managed lanes : final report, September 30, 2009.

DOT National Transportation Integrated Search

2009-09-01

Stated preference (SP) studies developed to estimate travelers value of travel time savings (VTTS) on : managed lanes (ML) may underestimate the VTTS. This study investigates survey design strategies and : differentiating the VTTS for ordinary and...

Gene Flow and the Measurement of Dispersal in Plant Populations.

ERIC Educational Resources Information Center

Nicholls, Marc S.

1986-01-01

Reviews methods of estimating pollen and seed dispersals and discusses the extent and frequency of gene exchange within and between populations. Offers suggestions for designing exercises suitable for estimating dispersal distances in natural plant populations. (ML)

Gynecomastia associated with herniated nipples: an optimal surgical approach.

PubMed

Jaiswal, Rohit; Pu, Lee L Q

2012-04-01

Gynecomastia is a common disorder observed in male plastic surgery patients. Treatment options may include observation, surgical excision, or liposuction techniques. Congenital herniated nipple is a more rare condition, especially in male patients. We present the case of a 12-year-old boy with bilateral gynecomastia and herniated nipple-areolar complexes. A staged repair was undertaken in this patient with grade 2 gynecomastia. The first operation was ultrasonic liposuction bilaterally, yielding 200 mL of aspirate from the left and 400 mL on the right, to correct the gynecomastia. The second procedure, performed 6 months later, was a bilateral periareolar mastopexy to repair the herniated nipple-areolar complexes. The result of the first procedure was flattened and symmetrical breast tissue bilaterally, essentially a correction of the gynecomastia. The herniated nipples were still present, however. Bilateral periareolar mastopexies were then performed with resulting reduction of the herniations. There were no complications with either procedure, and a good cosmetic result was achieved. A staged surgical approach was successful in correcting both conditions with an excellent aesthetic result and the advantage of decreased risk for nipple complications.

Spectrophotometric determination of fenoterol hydrobromide in pure form and dosage forms.

PubMed

El-Shabrawy, Y; Belal, F; Sharaf El-Din, M; Shalan, Sh

2003-10-01

A sensitive and rapid spectrophotometric procedure has been investigated for the determination of fenoterol either per se or in pharmaceutical preparations. The proposed procedure is based on the reaction between the drug and 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) at pH 7.2, using borate buffer, to produce a yellow adduct. The latter has maximum absorbance at 400 nm and obeys Beer's law within the concentration range 5-30 microg/ml. Regression analysis of the calibration data showed a good correlation coefficient (r=0.9996) with minimum detection limit of 0.24 microg/ml (6.2 x 10(-8) M). The proposed procedure has been successfully applied to the determination of this drug in its tablets and in syrup, the mean percent recoveries were 97.45+/-0.59 and 98.7+/-0.64%, respectively. The results obtained are in good agreement with those given using a reference method. The pharmaceutical additives other than active ingredient did not interfere. A proposal of the reaction pathway has been postulated.

Efficient design and inference for multistage randomized trials of individualized treatment policies.

PubMed

Dawson, Ree; Lavori, Philip W

2012-01-01

Clinical demand for individualized "adaptive" treatment policies in diverse fields has spawned development of clinical trial methodology for their experimental evaluation via multistage designs, building upon methods intended for the analysis of naturalistically observed strategies. Because often there is no need to parametrically smooth multistage trial data (in contrast to observational data for adaptive strategies), it is possible to establish direct connections among different methodological approaches. We show by algebraic proof that the maximum likelihood (ML) and optimal semiparametric (SP) estimators of the population mean of the outcome of a treatment policy and its standard error are equal under certain experimental conditions. This result is used to develop a unified and efficient approach to design and inference for multistage trials of policies that adapt treatment according to discrete responses. We derive a sample size formula expressed in terms of a parametric version of the optimal SP population variance. Nonparametric (sample-based) ML estimation performed well in simulation studies, in terms of achieved power, for scenarios most likely to occur in real studies, even though sample sizes were based on the parametric formula. ML outperformed the SP estimator; differences in achieved power predominately reflected differences in their estimates of the population mean (rather than estimated standard errors). Neither methodology could mitigate the potential for overestimated sample sizes when strong nonlinearity was purposely simulated for certain discrete outcomes; however, such departures from linearity may not be an issue for many clinical contexts that make evaluation of competitive treatment policies meaningful.

Use of plasma creatine kinase pharmacokinetics to estimate the amount of excercise-induced muscle damage in Beagles.

PubMed

Chanoit, G P; Lefebvre, H P; Orcel, K; Laroute, V; Toutain, P L; Braun, J P

2001-09-01

To assess the effects of moderate exercise on plasma creatine kinase (CK) pharmacokinetics and to estimate exercise-induced muscle damage in dogs. 6 untrained adult Beagles. The study was divided into 3 phases. In phase 1, dogs ran for 1 hour at a speed of 9 km/h, and samples were used to determine the area under the plasma CK activity versus time curve (AUC) induced by exercise. In phases 2 and 3, pharmacokinetics of CK were calculated in dogs during exercise and at rest, respectively. Values for AUC and plasma clearance (CI) were used to estimate muscle damage. At rest, values for Cl, steady-state volume of distribution (Vdss), and mean retention time (MRT) were 0.32+/-0.02 ml/kg of body weight/min, 57+/-173 ml/kg, and 3.0+/-0.57 h, respectively. During exercise, Cl decreased significantly (0.26+/-0.03 ml/kg/min), MRT increased significantly, (4.4+/-0.97 h), and Vdss remained unchanged. Peak of plasma CK activity (151+/-58.8 U/L) was observed 3 hours after completion of exercise. Estimated equivalent amount of muscle corresponding to the quantity of CK released was 41+/-29.3 mg/kg. These results revealed that exercise had a minor effect on CK disposition and that the equivalent amount of muscle damaged by moderate exercise was negligible. This study illustrates the relevance for use of the minimally invasive and quantitative pharmacokinetic approach when estimating muscle damage.

On-line solid phase extraction using the Prospekt-2 coupled with a liquid chromatography/tandem mass spectrometer for the determination of dextromethorphan, dextrorphan and guaifenesin in human plasma.

PubMed

Kuhlenbeck, Debbie L; Eichold, Thomas H; Hoke, Steven H; Baker, Timothy R; Mensen, Robert; Wehmeyer, Kenneth R

2005-01-01

An on-line liquid chromatography/tandem mass spectrometry (LC-MS/MS) procedure, using the Prospekt- 2 system, was developed and used for the determination of the levels of the active ingredients of cough/cold medications in human plasma matrix. The experimental configuration allows direct plasma injection by performing on- line solid phase extraction (SPE) on small cartridge columns prior to elution of the analyte(s) onto the analytical column and subsequent MS/MS detection. The quantitative analysis of three analytes with differing polarities, dextromethorphan (DEX), dextrorphan (DET) and guaifenesin (GG) in human plasma presented a significant challenge. Using stable-isotope-labeled internal standards for each analyte, the Prospekt-2 on-line methodology was evaluated for sensitivity, suppression, accuracy, precision, linearity, analyst time, analysis time, cost, carryover and ease of use. The lower limit of quantitation for the on-line SPE procedure for DEX, DET and GG was 0.05, 0.05 and 5.0 ng mL(-1), respectively, using a 0.1 mL sample volume. The linear range for DEX and DET was 0.05-50 ng mL(-1) and was 5-5,000 ng mL(-1) for GG. Accuracy and precision data for five different levels of QC samples were collected over three separate days. Accuracy ranged from 90% to 112% for all three analytes, while the precision, as measured by the %RSD, ranged from 1.5% to 16.0%

Antimicrobial susceptibility of Brachyspira hyodysenteriae isolated from 21 Polish farms.

PubMed

Zmudzki, J; Szczotka, A; Nowak, A; Strzelecka, H; Grzesiak, A; Pejsak, Z

2012-01-01

Swine dysentery (SD) is a common disease among pigs worldwide, which contributes to major production losses. Antimicrobial susceptibility testing of B. hyodysenteriae, the etiological agent of SD, is mainly performed by the agar dilution method. This method has certain limitations due to difficulties in interpretation of results. The aim of this study was the analysis of antimicrobial susceptibility of Brachyspira hyodysenteriae (B. hyodysenteriae) Polish field isolates by broth microdilution procedure. The study was performed on 21 isolates of B. hyodysenteriae, collected between January 2006 to December 2010 from cases of swine dysentery. VetMIC Brachyspira panels with antimicrobial agents (tiamulin, valnemulin, doxycycline, lincomycin, tylosin and ampicillin) were used for susceptibility testing of B. hyodysenteriae. The minimal inhibitory concentration (MIC) was determined by the broth dilution procedure. The lowest antimicrobial activity was demonstrated for tylosin and lincomycin, with inhibition of bacterial growth using concentrations > 128 microg/ml and 32 microg/ml, respectively. In the case of doxycycline, the MIC values were < or = 2.0 microg/ml. No decreased susceptibility to tiamulin was found among the Polish isolates and MIC values for this antibiotic did not exceed 1.0 microg/ml. The results of the present study confirmed that Polish B. hyodysenteriae isolates were susceptible to the main antibiotics (tiamulin and valnemulin) used in treatment of swine dysentery. Further studies are necessary to evaluate a possible slow decrease in susceptibility to tiamulin and valnemulin of B. hyodysenteriae strains in Poland.

Comparing adaptive procedures for estimating the psychometric function for an auditory gap detection task.

PubMed

Shen, Yi

2013-05-01

A subject's sensitivity to a stimulus variation can be studied by estimating the psychometric function. Generally speaking, three parameters of the psychometric function are of interest: the performance threshold, the slope of the function, and the rate at which attention lapses occur. In the present study, three psychophysical procedures were used to estimate the three-parameter psychometric function for an auditory gap detection task. These were an up-down staircase (up-down) procedure, an entropy-based Bayesian (entropy) procedure, and an updated maximum-likelihood (UML) procedure. Data collected from four young, normal-hearing listeners showed that while all three procedures provided similar estimates of the threshold parameter, the up-down procedure performed slightly better in estimating the slope and lapse rate for 200 trials of data collection. When the lapse rate was increased by mixing in random responses for the three adaptive procedures, the larger lapse rate was especially detrimental to the efficiency of the up-down procedure, and the UML procedure provided better estimates of the threshold and slope than did the other two procedures.

Gadolinium Use in Spine Pain Management Procedures for Patients with Contrast Allergies: Results in 527 Procedures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Safriel, Yair; Ang, Roberto; Ali, Muhammed

2008-03-15

Introduction. To review the safety and efficacy of gadolinium in spine pain management procedures in patients at high risk for a contrast reaction and who are not suitable candidates for the use of standard non-ionic contrast. Methods. We reviewed records over a 61-month period of all image-guided spinal pain management procedures where patients had allergies making them unsuitable candidates for standard non-ionic contrast and where gadolinium was used to confirm needle tip placement prior to injection of medication. Results. Three hundred and four outpatients underwent 527 procedures. A spinal needle was used in all but 41 procedures. Gadolinium was visualizedmore » using portable C-arm fluoroscopy in vivo allowing for confirmation of needle tip location. The gadolinium dose ranged from 0.2 to 10 ml per level. The highest dose received by one patient was 15.83 ml intradiscally during a three-level discogram. Three hundred and one patients were discharged without complication or known delayed complications. One patient had documented intrathecal injection but without sequelae and 2 patients who underwent cervical procedures experienced seizures requiring admission to the intensive care unit. Both the latter patients were discharged without any further complications. Conclusion. Based on our experience we recommend using gadolinium judiciously for needle tip confirmation. We feel more confident using gadolinium in the lumbar spine and in cervical nerve blocks. Gadolinium should probably not be used as an injectate volume expander. The indications for gadolinium use in cervical needle-guided spine procedures are less clear and use of a blunt-tipped needle should be considered.« less

Plasma exchange in the intensive care unit: Technical aspects and complications.

PubMed

Lemaire, Aurélie; Parquet, Nathalie; Galicier, Lionel; Boutboul, David; Bertinchamp, Rémi; Malphettes, Marion; Dumas, Guillaume; Mariotte, Eric; Peraldi, Marie-Noëlle; Souppart, Virginie; Schlemmer, Benoit; Azoulay, Elie; Canet, Emmanuel

2017-12-01

Data on plasma exchange therapy in the intensive care unit (ICU) setting are scarce. We aimed to describe the technical aspects and the adverse events associated with the procedure in critically ill patients. All adult patients treated by plasma exchange in the medical ICU of the Saint-Louis university hospital between January 1, 2013 and March 31, 2015 were prospectively included. We report on 260 plasma exchange procedures performed in 50 patients. The centrifugation technique was used for 159 (61%) procedures and the filtration technique for the other 101 (39%) procedures. Both techniques had similar efficacy to treat hyperviscosity syndrome (n = 18). Seventy (26.9%) of the 260 plasma exchange procedures were reported with at least one adverse reaction. Centrifugation and filtration techniques had similar rates of adverse reactions (23.9 vs. 31.7%, P = .19). Hypotension was the most reported (n = 21, 8%) and correlates with a low hematocrit before therapy. Most complications were related to allergic reactions to the replacement fluids. Coagulation disorders depended on the type of replacement fluid. The post-exchange fibrinogen level was decreased by 54% [48;66] with albumin 5%, and 4% [-5;17] with plasma frozen within 24 h. Twenty-three (22.8%) of the 101 filtration procedures experienced filter clotting. Filter clotting was associated with a higher volume exchange prescribed when compared to procedures without filter clotting (4600 [4000;5000] ml vs. 3900 [3600;4800] ml, P < .01). Plasma exchange is a relatively safe and generally well-tolerated procedure in the ICU setting. Most adverse events are unpredictable and related to minor allergic reactions. © 2017 Wiley Periodicals, Inc.

Total vaginectomy and urethral lengthening at time of neourethral prelamination in transgender men.

PubMed

Medina, Carlos A; Fein, Lydia A; Salgado, Christopher J

2017-11-29

For transgender men (TGM), gender-affirmation surgery (GAS) is often the final stage of their gender transition. GAS involves creating a neophallus, typically using tissue remote from the genital region, such as radial forearm free-flap phalloplasty. Essential to this process is vaginectomy. Complexity of vaginal fascial attachments, atrophy due to testosterone use, and need to preserve integrity of the vaginal epithelium for tissue rearrangement add to the intricacy of the procedure during GAS. We designed the technique presented here to minimize complications and contribute to overall success of the phalloplasty procedure. After obtaining approval from the Institutional Review Board, our transgender (TG) database at the University of Miami Hospital was reviewed to identify cases with vaginectomy and urethral elongation performed at the time of radial forearm free-flap phalloplasty prelamination. Surgical technique for posterior vaginectomy and anterior vaginal wall-flap harvest with subsequent urethral lengthening is detailed. Six patients underwent total vaginectomy and urethral elongation at the time of radial forearm free-flap phalloplasty prelamination. Mean estimated blood loss (EBL) was 290 ± 199.4 ml for the vaginectomy and urethral elongation, and no one required transfusion. There were no intraoperative complications (cystotomy, ureteral obstruction, enterotomy, proctotomy, or neurological injury). One patient had a urologic complication (urethral stricture) in the neobulbar urethra. Total vaginectomy and urethral lengthening procedures at the time of GAS are relatively safe procedures, and using the described technique provides excellent tissue for urethral prelamination and a low complication rate in both the short and long term.

Demonstrating Cell Traction--Using Hens' Egg Vitelline Membrane as Substratum.

ERIC Educational Resources Information Center

Downie, Roger

1987-01-01

Suggests ways in which hens' egg vitelline membranes can be used to demonstrate cell traction effects. Reviews procedures for using and culturing the membranes and identifies topic areas for student projects. (ML)

Prediction of functional aerobic capacity without exercise testing

NASA Technical Reports Server (NTRS)

Jackson, A. S.; Blair, S. N.; Mahar, M. T.; Wier, L. T.; Ross, R. M.; Stuteville, J. E.

1990-01-01

The purpose of this study was to develop functional aerobic capacity prediction models without using exercise tests (N-Ex) and to compare the accuracy with Astrand single-stage submaximal prediction methods. The data of 2,009 subjects (9.7% female) were randomly divided into validation (N = 1,543) and cross-validation (N = 466) samples. The validation sample was used to develop two N-Ex models to estimate VO2peak. Gender, age, body composition, and self-report activity were used to develop two N-Ex prediction models. One model estimated percent fat from skinfolds (N-Ex %fat) and the other used body mass index (N-Ex BMI) to represent body composition. The multiple correlations for the developed models were R = 0.81 (SE = 5.3 ml.kg-1.min-1) and R = 0.78 (SE = 5.6 ml.kg-1.min-1). This accuracy was confirmed when applied to the cross-validation sample. The N-Ex models were more accurate than what was obtained from VO2peak estimated from the Astrand prediction models. The SEs of the Astrand models ranged from 5.5-9.7 ml.kg-1.min-1. The N-Ex models were cross-validated on 59 men on hypertensive medication and 71 men who were found to have a positive exercise ECG. The SEs of the N-Ex models ranged from 4.6-5.4 ml.kg-1.min-1 with these subjects.(ABSTRACT TRUNCATED AT 250 WORDS).

Five Methods for Estimating Angoff Cut Scores with IRT

ERIC Educational Resources Information Center

Wyse, Adam E.

2017-01-01

This article illustrates five different methods for estimating Angoff cut scores using item response theory (IRT) models. These include maximum likelihood (ML), expected a priori (EAP), modal a priori (MAP), and weighted maximum likelihood (WML) estimators, as well as the most commonly used approach based on translating ratings through the test…

Weakly Informative Prior for Point Estimation of Covariance Matrices in Hierarchical Models

ERIC Educational Resources Information Center

Chung, Yeojin; Gelman, Andrew; Rabe-Hesketh, Sophia; Liu, Jingchen; Dorie, Vincent

2015-01-01

When fitting hierarchical regression models, maximum likelihood (ML) estimation has computational (and, for some users, philosophical) advantages compared to full Bayesian inference, but when the number of groups is small, estimates of the covariance matrix (S) of group-level varying coefficients are often degenerate. One can do better, even from…

Improvement of Parameter Estimations in Tumor Growth Inhibition Models on Xenografted Animals: Handling Sacrifice Censoring and Error Caused by Experimental Measurement on Larger Tumor Sizes.

PubMed

Pierrillas, Philippe B; Tod, Michel; Amiel, Magali; Chenel, Marylore; Henin, Emilie

2016-09-01

The purpose of this study was to explore the impact of censoring due to animal sacrifice on parameter estimates and tumor volume calculated from two diameters in larger tumors during tumor growth experiments in preclinical studies. The type of measurement error that can be expected was also investigated. Different scenarios were challenged using the stochastic simulation and estimation process. One thousand datasets were simulated under the design of a typical tumor growth study in xenografted mice, and then, eight approaches were used for parameter estimation with the simulated datasets. The distribution of estimates and simulation-based diagnostics were computed for comparison. The different approaches were robust regarding the choice of residual error and gave equivalent results. However, by not considering missing data induced by sacrificing the animal, parameter estimates were biased and led to false inferences in terms of compound potency; the threshold concentration for tumor eradication when ignoring censoring was 581 ng.ml(-1), but the true value was 240 ng.ml(-1).

Investigation of dynamic SPECT measurements of the arterial input function in human subjects using simulation, phantom and human studies

NASA Astrophysics Data System (ADS)

Winant, Celeste D.; Aparici, Carina Mari; Zelnik, Yuval R.; Reutter, Bryan W.; Sitek, Arkadiusz; Bacharach, Stephen L.; Gullberg, Grant T.

2012-01-01

Computer simulations, a phantom study and a human study were performed to determine whether a slowly rotating single-photon computed emission tomography (SPECT) system could provide accurate arterial input functions for quantification of myocardial perfusion imaging using kinetic models. The errors induced by data inconsistency associated with imaging with slow camera rotation during tracer injection were evaluated with an approach called SPECT/P (dynamic SPECT from positron emission tomography (PET)) and SPECT/D (dynamic SPECT from database of SPECT phantom projections). SPECT/P simulated SPECT-like dynamic projections using reprojections of reconstructed dynamic 94Tc-methoxyisobutylisonitrile (94Tc-MIBI) PET images acquired in three human subjects (1 min infusion). This approach was used to evaluate the accuracy of estimating myocardial wash-in rate parameters K1 for rotation speeds providing 180° of projection data every 27 or 54 s. Blood input and myocardium tissue time-activity curves (TACs) were estimated using spatiotemporal splines. These were fit to a one-compartment perfusion model to obtain wash-in rate parameters K1. For the second method (SPECT/D), an anthropomorphic cardiac torso phantom was used to create real SPECT dynamic projection data of a tracer distribution derived from 94Tc-MIBI PET scans in the blood pool, myocardium, liver and background. This method introduced attenuation, collimation and scatter into the modeling of dynamic SPECT projections. Both approaches were used to evaluate the accuracy of estimating myocardial wash-in parameters for rotation speeds providing 180° of projection data every 27 and 54 s. Dynamic cardiac SPECT was also performed in a human subject at rest using a hybrid SPECT/CT scanner. Dynamic measurements of 99mTc-tetrofosmin in the myocardium were obtained using an infusion time of 2 min. Blood input, myocardium tissue and liver TACs were estimated using the same spatiotemporal splines. The spatiotemporal maximum-likelihood expectation-maximization (4D ML-EM) reconstructions gave more accurate reconstructions than did standard frame-by-frame static 3D ML-EM reconstructions. The SPECT/P results showed that 4D ML-EM reconstruction gave higher and more accurate estimates of K1 than did 3D ML-EM, yielding anywhere from a 44% underestimation to 24% overestimation for the three patients. The SPECT/D results showed that 4D ML-EM reconstruction gave an overestimation of 28% and 3D ML-EM gave an underestimation of 1% for K1. For the patient study the 4D ML-EM reconstruction provided continuous images as a function of time of the concentration in both ventricular cavities and myocardium during the 2 min infusion. It is demonstrated that a 2 min infusion with a two-headed SPECT system rotating 180° every 54 s can produce measurements of blood pool and myocardial TACs, though the SPECT simulation studies showed that one must sample at least every 30 s to capture a 1 min infusion input function.

Prostate-specific Antigen (PSA) Density and Free to Total PSA Ratio in Diagnosing Prostate Cancer with Prostate-Specific Antigen Levels of 4.0 ng/ml or Less.

PubMed

Liu, Xin; Tang, Jie; Fei, Xiang; Li, Qiu-Yang

2015-11-01

We aimed to value the usefulness of free to total prostate-specific antigen and Prostate-specific antigen (PSA) density for prostate cancer in the patients with PSA levels of 4.0 ng/ml or less. A total of 343 subjects with PSA levels of 4.0 ng/ml or less were biopsied. All patients were divided into four groups according to the PSA levels: 0 to 1.0 ng/ml, 1.1 to 2.0 ng/ml, 2.1 to 3.0 ng/ml, and 3.1 to 4.0 ng/ml. The reliability of cancer detection in relation to the f/t PSA ratio and PSAD were estimated. Overall, 65 people were diagnosed with prostate cancer. The detection rate was 16.28%、17.17%, 21.82%, 25.00% in subjects with PSA levels of 0 to 1.0 ng/ml, 1.1 to 2.0 ng/ml, 2.1 to 3.0 ng/ml, and 3.1 to 4.0 ng/ml, respectively. The f/t PSA ratio was significantly lower in patients with prostate cancer and PSA levels of 2.1 to 4.0 ng/ml (P<0.05). The PSAD had no statistical significance between the two groups. Routine prostate biopsy should be undertaken if the f/t PSA ratio less than 15% with /without abnormal DRE/TRUS findings.

Catalytic spectrophotometric determination of iodide in pharmaceutical preparations and edible salt.

PubMed

El-Ries, M A; Khaled, Elmorsy; Zidane, F I; Ibrahim, S A; Abd-Elmonem, M S

2012-02-01

The catalytic effect of iodide on the oxidation of four dyes: viz. variamine blue (VB), methylene blue (MB), rhodamine B (RB), and malachite green (MG) with different oxidizing agents was investigated for the kinetic spectrophotometric determination of iodide. The above catalyzed reactions were monitored spectrophotometrically by following the change in dye absorbances at 544, 558, 660, or 617 nm for the VB, RB, MB, or MG catalyzed reactions, respectively. Under optimum conditions, iodide can be determined within the concentration levels 0.064-1.27 µg mL(-1) for VB method, 3.20-9.54 µg mL(-1) for RB method, 5.00-19.00 µg mL(-1) for the MB method, and 6.4-19.0 µg mL(-1) for the MG one, with detection limit reaching 0.004 µg mL(-1) iodide. The reported methods were highly sensitive, selective, and free from most interference. Applying the proposed procedures, trace amounts of iodide in pharmaceutical and edible salt samples were successfully determined without separation or pretreatment steps. Copyright © 2011 John Wiley & Sons, Ltd.

Comparative Pathogenicity of Lomentospora prolificans (Scedosporium prolificans) Isolates from Mexican Patients.

PubMed

Elizondo-Zertuche, Mariana; Montoya, Alexandra M; Robledo-Leal, Efrén; Garza-Veloz, Idalia; Sánchez-Núñez, Ana L; Ballesteros-Elizondo, Raquel; González, Gloria M

2017-08-01

We identified 11 Lomentospora prolificans isolates recovered from Mexican patients using phenotypic and molecular characteristics. The identification of isolates was assessed by internal transcribed spacer (ITS rDNA) sequencing. In vitro susceptibility to amphotericin B, fluconazole, voriconazole, posaconazole, caspofungin, anidulafungin and micafungin was determined according to Clinical and Laboratory Standards Institute (CLSI) procedures. Three isolates (07-2239, 11-2242 and 04-2673) were used to induce systemic infection in immunocompetent ICR mice. Survival and tissue burden studies were used as markers of pathogenicity. All of the strains were resistant to every antifungal tested with MIC's for AmB (8->8 µg/ml), VRC (16->16 µg/ml), PSC (16->16 µg/ml), FLC (64->64 µg/ml) and echinocandins with MICs ≥8 µg/ml. One hundred, ninety and sixty percent of the infected mice with the strains 07-2239, 11-2242 and 04-2673 died during the study, respectively. Regarding tissue burden, the highest fungal load of the infected mice was detected in brain followed by spleen and kidney, regardless of the strain.

Effects of vigorous mixing of blood vacuum tubes on laboratory test results.

PubMed

Lima-Oliveira, Gabriel; Lippi, Giuseppe; Salvagno, Gian Luca; Montagnana, Martina; Gelati, Matteo; Volanski, Waldemar; Boritiza, Katia Cristina; Picheth, Geraldo; Guidi, Gian Cesare

2013-02-01

To evaluate the effect of tubes mixing (gentle vs. vigorous) on diagnostic blood specimens collected in vacuum tube systems by venipuncture. Blood was collected for routine coagulation, immunochemistry and hematological testing from one hundred volunteers into six vacuum tubes: two 3.6 mL vacuum tubes containing 0.4 mL of buffered sodium citrate (9NC) 0.109 mol/L: 3.2 W/V%; two 3.5 mL vacuum tubes with clot activator and gel separator; and two 3.0 mL vacuum tubes containing 5.9 mg K(2)EDTA (Terumo Europe, Belgium). Immediately after the venipuncture all vacuum tubes (each of one additive type) were processed through two different procedures: i) Standard: blood specimens in K(2)EDTA- or sodium citrate-vacuum tubes were gently inverted five times whereas the specimens in tubes with clot activator and gel separator were gently inverted ten times, as recommended by the manufacturer; ii) Vigorous mix: all blood specimens were shaken up vigorously during 3-5s independently of the additive type inside the tubes. The significance of the differences between samples was assessed by Student's t-test or Wilcoxon ranked-pairs test after checking for normality. The level of statistical significance was set at P<0.05. No significant difference (P<0.05) was detected between the procedures for all tested parameters. Surprisingly only a visual alteration (presence of foam on the top) was shown by all the tubes mixed vigorously before centrifugation (Fig. 1 A, B and C). Moreover the serum tubes from vigorous mixing procedure shows a "blood ring" on the tube top after stopper removal (Fig. 1 D). Our results drop out a paradigm suggesting that the incorrect primary blood tubes mixing promotes laboratory variability. We suggest that similar evaluation should be done using other brands of vacuum tubes by each laboratory manager. Copyright © 2012 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Polyamide as an efficient sorbent for simultaneous interface-free determination of three Sudan dyes in saffron and urine using high-performance liquid chromatography-ultra violet detection.

PubMed

Saeidi, Iman; Barfi, Behruz; Payrovi, Moazameh; Feizy, Javid; Sheibani, Hojat A; Miri, Mina; Ghollasi Moud, Farahnaz

2015-01-01

With polyamide (PA) as an efficient sorbent for solid phase extraction (SPE) of Sudan dyes II, III and Red 7B from saffron and urine, their determination by HPLC was performed. The optimum conditions for SPE were achieved using 7 mL methanol/water (1:9, v/v, pH 7) as the washing solvent and 3 mL tetrahydrofuran for elution. Good clean-up and high (above 90%) recoveries were observed for all the analytes. The optimized mobile phase composition for HPLC analysis of these compounds was methanol-water (70:30, v/v). The SPE parameters, such as the maximum loading capacity and breakthrough volume, were also determined for each analyte. The limits of detection (LODs), limits of quantification (LOQs), linear ranges and recoveries for the analytes were 4.6-6.6 microg/L, 13.0-19.8 microg/L, 13.0-5000 microg/L (r2>0.99) and 92.5%-113.4%, respectively. The precisions (RSDs) of the overall analytical procedure, estimated by five replicate measurements for Sudan II, III and Red 7B in saffron and urine samples were 2.3%, 1.8% and 3.6%, respectively. The developed method is simple and successful in the application to the determination of Sudan dyes in saffron and urine samples with HPLC coupled with UV detection.

Estimation of age, growth and maturation of purpleback flying squid, Sthenoteuthis oualaniensis, in Bashi Channel, central Pacific Ocean

NASA Astrophysics Data System (ADS)

Liu, Bilin; Lin, Jingyuan; Feng, Chunlei; Li, Jianhua; Su, Hang

2017-06-01

The age, growth and maturation of Sthenoteuthis oualaniensis were determined with statolith data collected with a light purse seine from the Bashi Channel of central Pacific Ocean. The estimated longevity of the squid was no more than 6 months for females, and no more than 5 months for males. Growth in mantle length ( ML) was best described by logistic models for both females and males, while growth in body weight ( BW) was best fitted by power curves. The maximum absolute growth rate ( AGR) and instantaneous growth rate ( IGR) in ML or BW both occurred at 91-105 days for females and 76-90 days for males. Back calculated hatching dates were from October to January, with a peak in December, although the short duration of sampling date might have had an influence on the result. The lower percentage of mature females (37.2%) suggested that the study area during the sampling date was not a spawning ground for the species. Size and age at first maturity were 183 mm ML and 136 days for females, whereas they were 156 mm ML and 85 days for males.

Restoration of a single superresolution image from several blurred, noisy, and undersampled measured images.

PubMed

Elad, M; Feuer, A

1997-01-01

The three main tools in the single image restoration theory are the maximum likelihood (ML) estimator, the maximum a posteriori probability (MAP) estimator, and the set theoretic approach using projection onto convex sets (POCS). This paper utilizes the above known tools to propose a unified methodology toward the more complicated problem of superresolution restoration. In the superresolution restoration problem, an improved resolution image is restored from several geometrically warped, blurred, noisy and downsampled measured images. The superresolution restoration problem is modeled and analyzed from the ML, the MAP, and POCS points of view, yielding a generalization of the known superresolution restoration methods. The proposed restoration approach is general but assumes explicit knowledge of the linear space- and time-variant blur, the (additive Gaussian) noise, the different measured resolutions, and the (smooth) motion characteristics. A hybrid method combining the simplicity of the ML and the incorporation of nonellipsoid constraints is presented, giving improved restoration performance, compared with the ML and the POCS approaches. The hybrid method is shown to converge to the unique optimal solution of a new definition of the optimization problem. Superresolution restoration from motionless measurements is also discussed. Simulations demonstrate the power of the proposed methodology.

Development and Validation of Different Ultraviolet-Spectrophotometric Methods for the Estimation of Besifloxacin in Different Simulated Body Fluids.

PubMed

Singh, C L; Singh, A; Kumar, S; Kumar, M; Sharma, P K; Majumdar, D K

2015-01-01

In the present study a simple, accurate, precise, economical and specific UV-spectrophotometric method for estimation of besifloxacin in bulk and in different pharmaceutical formulation has been developed. The drug shows maximum λmax289 nm in distilled water, simulated tears and phosphate buffer saline. The linearity range of developed methods were in the range of 3-30 μg/ml of drug with a correlation coefficient (r(2)) 0.9992, 0.9989 and 0.9984 with respect to distilled water, simulated tears and phosphate buffer saline, respectively. Reproducibility by repeating methods as %RSD were found to be less than 2%. The limit of detection in different media was found to be 0.62, 0.72 and 0.88 μg/ml, respectively. The limit of quantification was found to be 1.88, 2.10, 2.60 μg/ml, respectively. The proposed method was validated statically according to International Conference on Harmonization guidelines with respect to specificity, linearity, range, accuracy, precision and robustness. The proposed methods of validation were found to be accurate and highly specific for the estimation of besifloxacin in different pharmaceutical formulations.

Holmium laser enucleation of the prostate combined with electrocautery resection: the mushroom technique.

PubMed

Hochreiter, Werner W; Thalmann, George N; Burkhard, Fiona C; Studer, Urs E

2002-10-01

The holmium laser allows bloodless enucleation of the prostate. A problem is how to remove a whole enucleated, free floating, large prostatic lobe from the bladder. A mechanical morcellator has been used to achieve tissue fragmentation but aspiration of and damage to the bladder wall are risks. Using the mushroom technique holmium laser enucleation and electrocautery resection can be combined without compromising the bloodless advantages of the laser procedure. We treated 156 patients with benign prostatic hyperplasia using a holmium laser with the mushroom technique. Preoperatively all patients were assessed using the International Prostate Symptom Score, maximum urine flow, ultrasound estimation of prostate volume and post-void residual urine, and pressure flow study. Laser enucleation of the prostatic lobes was performed at 66 W. Instead of releasing the lobes into the bladder they were left attached at the bladder neck by a narrow mushroom-like pedicle. At that point the vascular supply was almost completely interrupted and the lobes could easily be electroresected into small pieces without bleeding. Patients were followed 6, 12 and 24 months after the procedure. No patient had significant blood loss or signs of the transurethral resection syndrome. A total of 19 patients were treated while under oral anticoagulation without major bleeding problems. Complete followup was available on 125 patients. Median baseline International Prostate Symptom Score decreased from 20 to 3 at 6 months (p <0.05) and remained stable at 12 and 24 months. Median maximum urine flow increased from 8 to 20 ml. per second at 6, 12 and 24 months (p <0.05). Median baseline post-void residual urine decreased from 190 to 30 ml. at 6 months (p <0.05) and remained low at 20 and 30 ml. at 12 and 24 months, respectively. Urodynamic evaluation preoperatively and 6 months postoperatively was available in 83 cases. Relief of obstruction was documented with a statistically significant decrease in median detrusor pressure at maximum urine flow from 87 to 48 cm. water (p <0.05). Combining holmium laser enucleation and prostate electroresection with the mushroom technique is safe, efficient and bloodless surgical treatment for benign prostatic hyperplasia with sustained relief of obstruction. With this technique there is no need for additional devices, such as a mechanical tissue morcellator.

Rupture Propagation Imaging of Fluid Induced Events at the Basel EGS Project

NASA Astrophysics Data System (ADS)

Folesky, Jonas; Kummerow, Jörn; Shapiro, Serge A.

2014-05-01

The analysis of rupture properties using rupture propagation imaging techniques is a fast developing field of research in global seismology. Usually rupture fronts of large to megathrust earthquakes are subject of recent studies, like e.g. the 2004 Sumatra-Andaman earthquake or the 2011 Tohoku, Japan earthquake. The back projection technique is the most prominent technique in this field. Here the seismograms recorded at an array or at a seismic network are back shifted to a grid of possible source locations via a special stacking procedure. This can provide information on the energy release and energy distribution of the rupture which then can be used to find estimates of event properties like location, rupture direction, rupture speed or length. The procedure is fast and direct and it only relies on a reasonable velocity model. Thus it is a good way to rapidly estimate the rupture properties and it can be used to confirm independently achieved event information. We adopted the back projection technique and put it in a microseismic context. We demonstrated its usage for multiple synthetic ruptures within a reservoir model of microseismic scale in earlier works. Our motivation hereby is the occurrence of relatively large, induced seismic events at a number of stimulated geothermal reservoirs or waste disposal sites, having magnitudes ML ≥ 3.4 and yielding rupture lengths of several hundred meters. We use the configuration of the seismic network and reservoir properties of the Basel Geothermal Site to build a synthetic model of a rupture by modeling the wave field of multiple spatio-temporal separated single sources using Finite-Difference modeling. The focus of this work is the application of the Back Projection technique and the demonstration of its feasibility to retrieve the rupture properties of real fluid induced events. We take four microseismic events with magnitudes from ML 3.1 to 3.4 and reconstruct source parameters like location, orientation and length. By comparison with our synthetic results as well as independent localization studies and source mechanism studies in this area we can show, that the obtained results are reasonable and that the application of back projection imaging is not only possible for microseismic datasets of respective quality, but that it provides important additional insights in the rupture process.

Lung function decline over 25 years of follow-up among black and white adults in the ARIC study cohort.

PubMed

Mirabelli, Maria C; Preisser, John S; Loehr, Laura R; Agarwal, Sunil K; Barr, R Graham; Couper, David J; Hankinson, John L; Hyun, Noorie; Folsom, Aaron R; London, Stephanie J

2016-04-01

Interpretation of longitudinal information about lung function decline from middle to older age has been limited by loss to follow-up that may be correlated with baseline lung function or the rate of decline. We conducted these analyses to estimate age-related decline in lung function across groups of race, sex, and smoking status while accounting for dropout from the Atherosclerosis Risk in Communities Study. We analyzed data from 13,896 black and white participants, aged 45-64 years at the 1987-1989 baseline clinical examination. Using spirometry data collected at baseline and two follow-up visits, we estimated annual population-averaged mean changes in forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) by race, sex, and smoking status using inverse-probability-weighted independence estimating equations conditioning-on-being-alive. Estimated rates of FEV1 decline estimated using inverse-probability-weighted independence estimating equations conditioning on being alive were higher among white than black participants at age 45 years (e.g., male never smokers: black: -29.5 ml/year; white: -51.9 ml/year), but higher among black than white participants by age 75 (black: -51.2 ml/year; white: -26). Observed differences by race were more pronounced among men than among women. By smoking status, FEV1 declines were larger among current than former or never smokers at age 45 across all categories of race and sex. By age 60, FEV1 decline was larger among former and never than current smokers. Estimated annual declines generated using unweighted generalized estimating equations were smaller for current smokers at younger ages in all four groups of race and sex compared with results from weighted analyses that accounted for attrition. Using methods accounting for dropout from an approximately 25-year health study, estimated rates of lung function decline varied by age, race, sex, and smoking status, with largest declines observed among current smokers at younger ages. Published by Elsevier Ltd.

Microscale Procedure for Inorganic Qualitative Analysis with Emphasis on Writing Equations: Chemical Fingerprinting Applied to the "n"-bottle Problem of Matching Samples with Their Formulas

ERIC Educational Resources Information Center

Sattsangi, Prem D.

2014-01-01

A laboratory method for teaching inorganic qualitative analysis and chemical equations is described. The experiment has been designed to focus attention on cations and anions that react to form products. This leads to a logical approach to understand and write chemical equations. The procedure uses 3 mL plastic micropipettes to store and deliver…

QuakeML: XML for Seismological Data Exchange and Resource Metadata Description

NASA Astrophysics Data System (ADS)

Euchner, F.; Schorlemmer, D.; Becker, J.; Heinloo, A.; Kästli, P.; Saul, J.; Weber, B.; QuakeML Working Group

2007-12-01

QuakeML is an XML-based data exchange format for seismology that is under development. Current collaborators are from ETH, GFZ, USC, USGS, IRIS DMC, EMSC, ORFEUS, and ISTI. QuakeML development was motivated by the lack of a widely accepted and well-documented data format that is applicable to a broad range of fields in seismology. The development team brings together expertise from communities dealing with analysis and creation of earthquake catalogs, distribution of seismic bulletins, and real-time processing of seismic data. Efforts to merge QuakeML with existing XML dialects are under way. The first release of QuakeML will cover a basic description of seismic events including picks, arrivals, amplitudes, magnitudes, origins, focal mechanisms, and moment tensors. Further extensions are in progress or planned, e.g., for macroseismic information, location probability density functions, slip distributions, and ground motion information. The QuakeML language definition is supplemented by a concept to provide resource metadata and facilitate metadata exchange between distributed data providers. For that purpose, we introduce unique, location-independent identifiers of seismological resources. As an application of QuakeML, ETH Zurich currently develops a Python-based seismicity analysis toolkit as a contribution to CSEP (Collaboratory for the Study of Earthquake Predictability). We follow a collaborative and transparent development approach along the lines of the procedures of the World Wide Web Consortium (W3C). QuakeML currently is in working draft status. The standard description will be subjected to a public Request for Comments (RFC) process and eventually reach the status of a recommendation. QuakeML can be found at http://www.quakeml.org.

Restaurant menu labeling use among adults--17 states, 2012.

PubMed

Lee-Kwan, Seung Hee; Pan, Liping; Maynard, Leah; Kumar, Gayathri; Park, Sohyun

2014-07-11

Many persons underestimate the calories in restaurant foods. Increased attention has been given to menu labeling (ML) as a way to provide consumers with point-of-purchase information that can help them reduce calorie intake and make healthier dietary choices. In 2010, a federal law was passed requiring restaurants with 20 or more establishments to display calorie information on menus and menu boards.* The regulations to implement this federal law have not been finalized, but some states and local jurisdictions have implemented their own ML policies, and many restaurants have already begun providing ML. To assess fast food and chain restaurant ML use by state and by demographic subgroup, CDC examined self-reported ML use by adults in 17 states that used the Sugar-Sweetened Beverages and Menu Labeling optional module in the 2012 Behavioral Risk Factor Surveillance System (BRFSS) survey. Based on approximately 97% of adult BRFSS respondents who noticed ML information at restaurants, the estimated overall proportion of ML users in the 17 states was 57.3% (range = 48.7% in Montana to 61.3% in New York). The prevalence of ML use was higher among women than men for all states; the patterns varied by age group and race/ethnicity across states. States and public health professionals can use these findings to track the use of ML and to develop targeted interventions to increase awareness and use of ML among nonusers.

Design, Development and Testing of Web Services for Multi-Sensor Snow Cover Mapping

NASA Astrophysics Data System (ADS)

Kadlec, Jiri

This dissertation presents the design, development and validation of new data integration methods for mapping the extent of snow cover based on open access ground station measurements, remote sensing images, volunteer observer snow reports, and cross country ski track recordings from location-enabled mobile devices. The first step of the data integration procedure includes data discovery, data retrieval, and data quality control of snow observations at ground stations. The WaterML R package developed in this work enables hydrologists to retrieve and analyze data from multiple organizations that are listed in the Consortium of Universities for the Advancement of Hydrologic Sciences Inc (CUAHSI) Water Data Center catalog directly within the R statistical software environment. Using the WaterML R package is demonstrated by running an energy balance snowpack model in R with data inputs from CUAHSI, and by automating uploads of real time sensor observations to CUAHSI HydroServer. The second step of the procedure requires efficient access to multi-temporal remote sensing snow images. The Snow Inspector web application developed in this research enables the users to retrieve a time series of fractional snow cover from the Moderate Resolution Imaging Spectroradiometer (MODIS) for any point on Earth. The time series retrieval method is based on automated data extraction from tile images provided by a Web Map Tile Service (WMTS). The average required time for retrieving 100 days of data using this technique is 5.4 seconds, which is significantly faster than other methods that require the download of large satellite image files. The presented data extraction technique and space-time visualization user interface can be used as a model for working with other multi-temporal hydrologic or climate data WMTS services. The third, final step of the data integration procedure is generating continuous daily snow cover maps. A custom inverse distance weighting method has been developed to combine volunteer snow reports, cross-country ski track reports and station measurements to fill cloud gaps in the MODIS snow cover product. The method is demonstrated by producing a continuous daily time step snow presence probability map dataset for the Czech Republic region. The ability of the presented methodology to reconstruct MODIS snow cover under cloud is validated by simulating cloud cover datasets and comparing estimated snow cover to actual MODIS snow cover. The percent correctly classified indicator showed accuracy between 80 and 90% using this method. Using crowdsourcing data (volunteer snow reports and ski tracks) improves the map accuracy by 0.7--1.2%. The output snow probability map data sets are published online using web applications and web services. Keywords: crowdsourcing, image analysis, interpolation, MODIS, R statistical software, snow cover, snowpack probability, Tethys platform, time series, WaterML, web services, winter sports.

Dissolution of bulk specimens of silicon nitride

NASA Technical Reports Server (NTRS)

Davis, W. F.; Merkle, E. J.

1981-01-01

An accurate chemical characterization of silicon nitride has become important in connection with current efforts to incorporate components of this material into advanced heat engines. However, there are problems concerning a chemical analysis of bulk silicon nitride. Current analytical methods require the pulverization of bulk specimens. A pulverization procedure making use of grinding media, on the other hand, will introduce contaminants. A description is given of a dissolution procedure which overcomes these difficulties. It has been found that up to at least 0.6 g solid pieces of various samples of hot pressed and reaction bonded silicon nitride can be decomposed in a mixture of 3 mL hydrofluoric acid and 1 mL nitric acid overnight at 150 C in a Parr bomb. High-purity silicon nitride is completely soluble in nitric acid after treatment in the bomb. Following decomposition, silicon and hydrofluoric acid are volatilized and insoluble fluorides are converted to a soluble form.

Rapid Two-Step Procedure for Large-Scale Purification of Pediocin-Like Bacteriocins and Other Cationic Antimicrobial Peptides from Complex Culture Medium

PubMed Central

Uteng, Marianne; Hauge, Håvard Hildeng; Brondz, Ilia; Nissen-Meyer, Jon; Fimland, Gunnar

2002-01-01

A rapid and simple two-step procedure suitable for both small- and large-scale purification of pediocin-like bacteriocins and other cationic peptides has been developed. In the first step, the bacterial culture was applied directly on a cation-exchange column (1-ml cation exchanger per 100-ml cell culture). Bacteria and anionic compounds passed through the column, and cationic bacteriocins were subsequently eluted with 1 M NaCl. In the second step, the bacteriocin fraction was applied on a low-pressure, reverse-phase column and the bacteriocins were detected as major optical density peaks upon elution with propanol. More than 80% of the activity that was initially in the culture supernatant was recovered in both purification steps, and the final bacteriocin preparation was more than 90% pure as judged by analytical reverse-phase chromatography and capillary electrophoresis. PMID:11823243

Quantitative bioanalysis of strontium in human serum by inductively coupled plasma-mass spectrometry

PubMed Central

Somarouthu, Srikanth; Ohh, Jayoung; Shaked, Jonathan; Cunico, Robert L; Yakatan, Gerald; Corritori, Suzana; Tami, Joe; Foehr, Erik D

2015-01-01

Aim: A bioanalytical method using inductively-coupled plasma-mass spectrometry to measure endogenous levels of strontium in human serum was developed and validated. Results & methodology: This article details the experimental procedures used for the method development and validation thus demonstrating the application of the inductively-coupled plasma-mass spectrometry method for quantification of strontium in human serum samples. The assay was validated for specificity, linearity, accuracy, precision, recovery and stability. Significant endogenous levels of strontium are present in human serum samples ranging from 19 to 96 ng/ml with a mean of 34.6 ± 15.2 ng/ml (SD). Discussion & conclusion: Calibration procedures and sample pretreatment were simplified for high throughput analysis. The validation demonstrates that the method was sensitive, selective for quantification of strontium (88Sr) and is suitable for routine clinical testing of strontium in human serum samples. PMID:28031925

An empirical mass-loss law for Population II giants from the Spitzer-IRAC survey of Galactic globular clusters

NASA Astrophysics Data System (ADS)

Origlia, L.; Ferraro, F. R.; Fabbri, S.; Fusi Pecci, F.; Dalessandro, E.; Rich, R. M.; Valenti, E.

2014-04-01

Aims: The main aim of the present work is to derive an empirical mass-loss (ML) law for Population II stars in first and second ascent red giant branches. Methods: We used the Spitzer InfraRed Array Camera (IRAC) photometry obtained in the 3.6-8 μm range of a carefully chosen sample of 15 Galactic globular clusters spanning the entire metallicity range and sampling the vast zoology of horizontal branch (HB) morphologies. We complemented the IRAC photometry with near-infrared data to build suitable color-magnitude and color-color diagrams and identify mass-losing giant stars. Results: We find that while the majority of stars show colors typical of cool giants, some stars show an excess of mid-infrared light that is larger than expected from their photospheric emission and that is plausibly due to dust formation in mass flowing from them. For these stars, we estimate dust and total (gas + dust) ML rates and timescales. We finally calibrate an empirical ML law for Population II red and asymptotic giant branch stars with varying metallicity. We find that at a given red giant branch luminosity only a fraction of the stars are losing mass. From this, we conclude that ML is episodic and is active only a fraction of the time, which we define as the duty cycle. The fraction of mass-losing stars increases by increasing the stellar luminosity and metallicity. The ML rate, as estimated from reasonable assumptions for the gas-to-dust ratio and expansion velocity, depends on metallicity and slowly increases with decreasing metallicity. In contrast, the duty cycle increases with increasing metallicity, with the net result that total ML increases moderately with increasing metallicity, about 0.1 M⊙ every dex in [Fe/H]. For Population II asymptotic giant branch stars, we estimate a total ML of ≤0.1 M⊙, nearly constant with varying metallicity. This work is based on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA. Support for this work was provided by NASA through an award issued by JPL/Caltech.Appendix A is available in electronic form at http://www.aanda.org

The efficacy of clove oil as an anaesthetic and in euthanasia procedure for small-sized tropical fishes.

PubMed

Fernandes, I M; Bastos, Y F; Barreto, D S; Lourenço, L S; Penha, J M

2017-01-01

Clove oil is used as a fish anesthetic because it is a natural and inexpensive product with low toxicity risks. The goal of the present study was to determine the appropriate concentration of clove oil for small-sized tropical fish to be used in mark-recapture studies or when individuals are to be sacrificed. We applied three different clove oil concentrations (D1=0.05 mL, D2=0.10 mL and D3=0.20 mL per 500 mL of water) on three small-sized fish species. We found a negative relationship between induction time and treatment for two species (Hyphessobrycon sp.1 and Hemigrammus sp.), while concentration was unrelated to recovery time. Fish body length was positively related to induction time in the D2 treatment for Hemigrammus sp., and negatively for Hyphessobrycon sp.1 in the D1 treatment, but was unrelated to recovery time for three species and treatments. Mortality rates varied across treatments, but higher rates were observed with higher clove oil concentrations. We conclude that 0.05 mL of clove oil per 500 mL of water is the most efficient dose for studies where fish will be released back to their natural habitats, while 0.20 mL of clove oil is recommended for studies that require fish euthanization for further laboratory analyses.

The Chemical Characterization of Pollutants in Waste Water from Volunteer Army Ammunition Plant.

DTIC Science & Technology

1981-08-01

tionating procedure was repeated with 40 mL of CW3 after adjusting its pH to 2 with sulfuric acid , and with 40 ml, of CW3 after adjusting its pH to 12 with...dissolved solids. Elemental and anionic analysis of the water solubles, shown in column 5 of table 3, indicated that nitrate, nitrite, silica and sulfate ...spectrophotometry revealed the presence of sulfate , nitrate, and nitrite. Atomic absorption showed an abnormal amount of sodium. Since this sample was reported at

Proposed Tier 2 Screening Criteria and Tier 3 Field Procedures for Evaluation of Vapor Intrusion (ESTCP Cost and Performance Report)

DTIC Science & Technology

2012-08-01

Interstate Technology & Regulatory Council, Washington, DC, Copyright 2007. McHugh T.E., D.E. Hammond, T. Nickels , and B. Hartman. 2008. Use of...based corrective action have realized significant cost savings for their corrective action programs (Connor and McHugh , 2002). As described above...Groundwater (Tier 2) VOCs USEPA 8260B 40 mL VOA vial HCl 14 days Vapor (Tier 2 and Tier 3) Radon McHugh et al., 2008 500 mL Tedlar bag None 14

Topical intra-articular compared with intravenous tranexamic acid to reduce blood loss in primary total knee replacement: a double-blind, randomized, controlled, noninferiority clinical trial.

PubMed

Gomez-Barrena, Enrique; Ortega-Andreu, Miguel; Padilla-Eguiluz, Norma G; Pérez-Chrzanowska, Hanna; Figueredo-Zalve, Reyes

2014-12-03

Abundant literature regarding the use of intravenous tranexamic acid (TXA) in primary total knee replacement is available. Randomized controlled trials have confirmed the efficacy of topical TXA compared with placebo, but the comparison between topical and intravenous TXA is unclear. The present study was designed to verify noninferior efficacy and safety of topical intra-articular TXA compared with intravenous TXA in primary total knee replacement with cemented implants. A Phase-III, single-center, double-blind, randomized, controlled clinical trial was performed to compare topical intra-articular TXA (3 g of TXA in 100 mL of physiological saline solution) with two intravenous doses of TXA (15 mg/kg in 100 mL of physiological saline solution, one dose before tourniquet release and another three hours after surgery) in a multimodal protocol for blood loss prevention. The primary outcome was the blood transfusion rate, and the secondary outcomes included visible blood loss (as measured in the drain) at twenty-four hours postoperatively and invisible blood loss (as estimated from the Nadler formula) at forty-eight hours postoperatively. The sample size of seventy-eight patients was calculated to give a statistical power of 99% for demonstrating noninferiority. Thirty-nine patients each were allocated to receive topical intra-articular TXA (the experimental group) and intravenous TXA (the control group); there were no significant differences in demographics or preoperative laboratory values between the groups. Noninferiority was estimated by comparing the confidence intervals with a delta of 10%. Student t and Mann-Whitney tests were used to assess the significance of any differences. The transfusion rate was zero in both groups; thus, noninferiority was demonstrated for the primary efficacy end point, suggesting equivalence. Noninferiority was also demonstrated for the secondary efficacy end points. Drain blood loss at twenty-four hours was 315.6 mL (95% confidence interval [CI], 248.5 to 382.7 mL) in the experimental group and 308.1 mL (95% CI, 247.6 to 368.5 mL) in the control group (p = 0.948, Mann-Whitney). Also, estimated blood loss at forty-eight hours was 1259.0 mL (95% CI, 1115.6 to 1402.3 mL) in the experimental group and 1317.9 mL (95% CI, 1175.4 to 1460.4 mL) in the control group (p = 0.837, Mann-Whitney). No significant safety differences were seen between groups. Topical administration of TXA according to the described protocol demonstrated noninferiority compared with intravenous TXA, with no safety concerns. This randomized controlled trial supports the topical intra-articular administration of TXA in primary total knee replacement with cemented implants. Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence. Copyright © 2014 by The Journal of Bone and Joint Surgery, Incorporated.

The Order-Restricted Association Model: Two Estimation Algorithms and Issues in Testing

ERIC Educational Resources Information Center

Galindo-Garre, Francisca; Vermunt, Jeroen K.

2004-01-01

This paper presents a row-column (RC) association model in which the estimated row and column scores are forced to be in agreement with a priori specified ordering. Two efficient algorithms for finding the order-restricted maximum likelihood (ML) estimates are proposed and their reliability under different degrees of association is investigated by…

Is the ML Chi-Square Ever Robust to Nonnormality? A Cautionary Note with Missing Data

ERIC Educational Resources Information Center

Savalei, Victoria

2008-01-01

Normal theory maximum likelihood (ML) is by far the most popular estimation and testing method used in structural equation modeling (SEM), and it is the default in most SEM programs. Even though this approach assumes multivariate normality of the data, its use can be justified on the grounds that it is fairly robust to the violations of the…

PREOPERATIVE COMPUTED TOMOGRAPHY VOLUMETRY AND GRAFT WEIGHT ESTIMATION IN ADULT LIVING DONOR LIVER TRANSPLANTATION.

PubMed

Pinheiro, Rafael S; Cruz, Ruy J; Andraus, Wellington; Ducatti, Liliana; Martino, Rodrigo B; Nacif, Lucas S; Rocha-Santos, Vinicius; Arantes, Rubens M; Lai, Quirino; Ibuki, Felicia S; Rocha, Manoel S; D Albuquerque, Luiz A C

2017-01-01

Computed tomography volumetry (CTV) is a useful tool for predicting graft weights (GW) for living donor liver transplantation (LDLT). Few studies have examined the correlation between CTV and GW in normal liver parenchyma. To analyze the correlation between CTV and GW in an adult LDLT population and provide a systematic review of the existing mathematical models to calculate partial liver graft weight. Between January 2009 and January 2013, 28 consecutive donors undergoing right hepatectomy for LDLT were retrospectively reviewed. All grafts were perfused with HTK solution. Estimated graft volume was estimated by CTV and these values were compared to the actual graft weight, which was measured after liver harvesting and perfusion. Median actual GW was 782.5 g, averaged 791.43±136 g and ranged from 520-1185 g. Median estimated graft volume was 927.5 ml, averaged 944.86±200.74 ml and ranged from 600-1477 ml. Linear regression of estimated graft volume and actual GW was significantly linear (GW=0.82 estimated graft volume, r2=0.98, slope=0.47, standard deviation of 0.024 and p<0.0001). Spearman Linear correlation was 0.65 with 95% CI of 0.45 - 0.99 (p<0.0001). The one-to-one rule did not applied in patients with normal liver parenchyma. A better estimation of graft weight could be reached by multiplying estimated graft volume by 0.82. A volumetria por tomografia computadorizada (VTC) é uma ferramenta útil para a previsão do peso do enxerto (PE) para o transplante hepático com doador vivo (TFDV). Poucos estudos examinaram a correlação entre o VTC e PE no parênquima hepático normal. Analisar a correlação entre VTC e PE em uma população adulta de doadores para o TFDV e realização de revisão sistemática dos modelos matemáticos existentes para calcular o peso de enxertos hepáticos parciais. Foram revisados retrospectivamente 28 doadores consecutivos submetidos à hepatectomia direita para o TFDV entre janeiro de 2009 a janeiro de 2013. Todos os doadores eram adultos saudáveis ​​com VTC pré-operatório. Os enxertos foram perfundidos com solução de preservação HTK. O volume estimado foi obtido por VTC e estes valores foram comparados com o peso real do enxerto, o qual foi aferido depois da hepatectomia e perfusão do enxerto. A mediana do PE real foi de 782,5 g, média de 791,43±136 g, variando de 520-1185 g. A mediana do volume estimado do enxerto foi de 927,5 ml, média de 944,86±200,74 ml e variou de 600-1477 ml. A regressão linear volume estimado do enxerto e PE real foi significativamente linear (PE=0.82 do volume estimado do enxerto, r2=0,98, declive=0,47, desvio-padrão de 0,024 e p<0,0001). Correlação linear de Spearman foi de 0,65, com IC de 95% do 0,45-0,99 (p<0,0001). A regra de "um-para-um" não deve ser empregada em pacientes com parênquima hepático normal. A melhor estimativa do peso do enxerto hepático de doador vivo pode ser alcançado através da multiplicação do VTC por 0,82.

Are cystatin C-based equations superior to creatinine-based equations for estimating GFR in Chinese elderly population?

PubMed

Pei, Xiaohua; Liu, Qiao; He, Juan; Bao, Lihua; Yan, Chengjing; Wu, Jianqing; Zhao, Weihong

2012-12-01

Cystatin C has been proposed as a surrogate marker of kidney function. The elderly population accounts for the largest proportion of chronic kidney disease (CKD) patients. The aim of this study was to assess the diagnostic value of serum cystatin C and compare the applicability of cystatin C-based equations with serum creatinine (Scr)-based equations for estimating glomerular filtration rate (GFR). The estimated GFR (eGFR) values from six cystatin C-based equations (Tan, MacIsaac, Ma, Stevens1-3) and three Scr-based equations (CG, MDRD, CKD-EPI) were compared with the reference GFR (rGFR) values from 99mTc-DTPA renal dynamic imaging method. A total of 110 elderly Chinese (60-92 year, 71.05±7.62 year) were enrolled. Cystatin C had better diagnostic value than Scr (relationship coefficient with rGFR: cystatin C -0.847 vs. Scr -0.729, P<0.01; sensitivity: cystatin C 0.90 vs. Scr 0.55, P<0.01; AUCROC: cystatin C 0.857 vs. Scr 0.757, P<0.01). All the equations predicted GFR more accurately for rGFR≥60 ml/min/1.73 m2 than for rGFR<60 ml/min/1.73 m2. Most equations had acceptable accuracy. The cystatin C-based equations deviated from rGFR by -12.78 ml/min/1.73 m2 to -2.12 ml/min/1.73 m2, with accuracy varying from 64.6 to 82.7%. The Scr-based equations deviated from rGFR by -5.37 ml/min/1.73 m2 to -0.68 ml/min/1.73 m2, with accuracy varying from 77.3 to 79.1%. The CKD-EPI, MacIsaac and Ma equations predicted no bias with rGFR (P>0.05), with higher accuracy and lower deviation in the total group. The MacIsaac, CKD-EPI and Stevens3 equations could be optimal for those with normal and mildly impaired kidney function, whereas the Ma equation for those with CKD. Cystatin C is a promising kidney function marker. However, not all cystatin C-based equations could be superior to the Scr-equations.

Accommodation-Amplitudes following an Accommodative Lens Refilling Procedure — an in vivo Update

PubMed Central

Nishi, Okihiro; Nishi, Yutaro; Chang, S.; Nishi, Kayo

2014-01-01

Purpose To investigate whether a newly developed lens refilling procedure can provide some accommodation in monkey eyes and to evaluate the difference in accommodation with different degrees of capsular bag refilling. Setting Jinshikai Medical Foundation, Nishi Eye Hospital, Osaka, Japan. Design Experimental monkey study. Methods Following a central 3–4 mm continuous curvilinear capsulorhexis, phacoemulsification was performed in the usual manner. A novel accommodative membrane intraocular lens for sealing capsular opening was implanted into the capsular bag. Silicone polymers were injected beneath the intraocular lens into the capsular bag through the delivery hole. In three study groups, each with six monkey eyes, the lens capsule was refilled with 0.08 ml corresponding to 65% bag volume, 0.1 ml corresponding to 80% bag volume, and 0.125 ml of silicone polymers corresponding to 100% bag volume, respectively. To calculate the accommodation-amplitudes achieved, automated refractometry was performed before and 1 hour after the topical 4% pilocarpine application before and four weeks after surgery. Results The refilling technique was successful in all monkeys without polymer leakage. Accommodation-amplitudes attained were 2.56 ± 0.74 dioptries (D), 2.42 ± 1.00D, and 2.71 ± 0.63D, respectively, 4 weeks after surgery in the three study groups. Conclusions Using the technique, some accommodation could be obtained in the young monkey eyes. Leakage of the injectable silicone polymer and anterior capsular opacification at least in the visual axis could be avoided. The results suggest that this lens refilling procedure warrants further studies for a possible clinical application. PMID:24461501

Consensus for the Treatment of Varicose Vein with Radiofrequency Ablation

PubMed Central

Joh, Jin Hyun; Kim, Woo-Shik; Jung, In Mok; Park, Ki-Hyuk; Lee, Taeseung; Kang, Jin Mo

2014-01-01

The objective of this paper is to introduce the schematic protocol of radiofrequency (RF) ablation for the treatment of varicose veins. Indication: anatomic or pathophysiologic indication includes venous diameter within 2–20 mm, reflux time ≥0.5 seconds and distance from the skin ≥5 mm or subfascial location. Access: it is recommended to access at or above the knee joint for great saphenous vein and above the mid-calf for small saphenous vein. Catheter placement: the catheter tip should be placed 2.0 cm inferior to the saphenofemoral or saphenopopliteal junction. Endovenous heat-induced thrombosis ≥class III should be treated with low-molecular weight heparin. Tumescent solution: the composition of solution can be variable (e.g., 2% lidocaine 20 mL+500 mL normal saline+bicarbonate 2.5 mL with/without epinephrine). Infiltration can be done from each direction. Ablation: two cycles’ ablation for the first proximal segment of saphenous vein and the segment with the incompetent perforators is recommended. The other segments should be ablated one time. During RF energy delivery, it is recommended to apply external compression. Concomitant procedure: It is recommended to do simultaneously ambulatory phlebectomy. For sclerotherapy, it is recommended to defer at least 2 weeks. Post-procedural management: post-procedural ambulation is encouraged to reduce the thrombotic complications. Compression stocking should be applied for at least 7 days. Minor daily activity is not limited, but strenuous activities should be avoided for 2 weeks. It is suggested to take showers after 24 hours and tub baths, swimming, or soaking in water after 2 weeks. PMID:26217628

One normal void and residual following MUS surgery is all that is necessary in most patients.

PubMed

Ballard, Paul; Shawer, Sami; Anderson, Colette; Khunda, Aethele

2018-04-01

There is considerable variation worldwide on how the assessment of voiding function is performed following midurethral sling (MUS) surgery. There is potentially a financial cost, and reduction in efficiency when patient discharge is delayed. Using our current practice of two normal void and residual (V&R) readings before discharge, the aim of this retrospective study was to evaluate the likelihood of an abnormal second V&R test if the first V&R test was normal in order to determine if a policy of discharge after only one satisfactory V&R test is reasonable. Data from 400 patients who had had MUS surgery with or without other procedures were collected. Our unit protocol included two consecutive voids of greater than 200 ml with residuals less than 150 ml before discharge. The patients were divided into the following groups: MUS only, MUS plus anterior colporrhaphy (AR) plus any other procedures (MUS/AR), and MUS with any non-AR procedures (MUS+). Complete datasets were available for 335 patients. Once inadequate tests (low volume voids <200 ml) had been excluded (28% overall), the likelihood of an abnormal second V&R test if the first test was normal was 7.1% overall, but 3.6% for MUS, 11.5% for MUS/AR and 8.6% for MUS+. The findings in the MUS-only group indicate that it is probably safe to discharge patients after one satisfactory V&R test, as long as safety measures such as 'open access' are available so that patients have unhindered readmission if problems arise.

Usefulness and Limitation of Manual Aspiration Immediately After Pneumothorax Complicating Interventional Radiological Procedures with the Transthoracic Approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yamagami, Takuji, E-mail: yamagami@koto.kpu-m.ac.jp; Kato, Takeharu; Hirota, Tatsuya

2006-12-15

The goal of this study was to evaluate the efficacy of simple aspiration of air from the pleural space to prevent increased pneumothorax and avoid chest tube placement in cases of pneumothorax following interventional radiological procedures performed under computed tomography fluoroscopic guidance with the transthoracic percutaneous approach. While still on the scanner table, 102 cases underwent percutaneous manual aspiration of a moderate or large pneumothorax that had developed during mediastinal, lung, and transthoracic liver biopsies and ablations of lung and hepatic tumors (independent of symptoms). Air was aspirated from the pleural space by an 18- or 20-gauge intravenous catheter attachedmore » to a three-way stopcock and 20- or 50-mL syringe. We evaluated the management of each such case during and after manual aspiration. In 87 of the 102 patients (85.3%), the pneumothorax had resolved completely on follow-up chest radiographs without chest tube placement, but chest tube placement was required in 15 patients. Requirement of chest tube insertion significantly increased in parallel with the increased volume of aspirated air. When receiver-operating characteristic curves were applied retrospectively, the optimal cutoff level of aspirated air on which to base a decision to abandon manual aspiration alone and resort to chest tube placement was 670 mL. Percutaneous manual aspiration of the pneumothorax performed immediately after the procedure might prevent progressive pneumothorax and eliminate the need for chest tube placement. However, when the amount of aspirated air is large (such as more than 670 mL), chest tube placement should be considered.« less

Determination of vitamins D2, D3, K1 and K3 and some hydroxy metabolites of vitamin D3 in plasma using a continuous clean-up-preconcentration procedure coupled on-line with liquid chromatography-UV detection.

PubMed

Ortiz Boyer, F; Fernández Romero, J M; Luque de Castro, M D; Quesada, J M

1999-03-01

A semi-automatic procedure for the continuous clean-up and concentration of several fat-soluble vitamins prior to their separation by HPLC and UV detection is reported. The procedure is based on the use of a minicolumn packed with aminopropylsilica as sorbent located prior to the chromatographic detection system. The overall process was developed and applied to the main liposoluble vitamins (A, D2, D3, E, K1, K3) and several hydroxy metabolites of vitamin D3 [25-(OH)-D3,24,25-(OH)2-D3 and 1,25-(OH)2-D3]. All the analytes were monitored at a compromise wavelength of 270 nm. Calibration graphs were constructed between 0.01 and 100 ng ml-1 for vitamin D2 and D3 and their hydroxy metabolites, between 0.1 and 100 ng ml-1 for vitamin A, K1 and K3 and between 1 and 100 ng ml-1 for vitamin E, with excellent regression coefficients (> or = 0.9901) in all cases. The precision was established at two concentration levels with acceptable RSDs in all instances (between 3.6 and 8.7%). The method was appropriate for the determination of vitamin D2, D3, K1 and K3 and the 24,25-dihydroxy and 25-hydroxy metabolites of vitamin D3 in human plasma. The method was applied to plasma samples spiked with the target analytes and the recoveries ranged between 78 and 109%.

Beak measurements of octopus ( Octopus variabilis) in Jiaozhou Bay and their use in size and biomass estimation

NASA Astrophysics Data System (ADS)

Xue, Ying; Ren, Yiping; Meng, Wenrong; Li, Long; Mao, Xia; Han, Dongyan; Ma, Qiuyun

2013-09-01

Cephalopods play key roles in global marine ecosystems as both predators and preys. Regressive estimation of original size and weight of cephalopod from beak measurements is a powerful tool of interrogating the feeding ecology of predators at higher trophic levels. In this study, regressive relationships among beak measurements and body length and weight were determined for an octopus species ( Octopus variabilis), an important endemic cephalopod species in the northwest Pacific Ocean. A total of 193 individuals (63 males and 130 females) were collected at a monthly interval from Jiaozhou Bay, China. Regressive relationships among 6 beak measurements (upper hood length, UHL; upper crest length, UCL; lower hood length, LHL; lower crest length, LCL; and upper and lower beak weights) and mantle length (ML), total length (TL) and body weight (W) were determined. Results showed that the relationships between beak size and TL and beak size and ML were linearly regressive, while those between beak size and W fitted a power function model. LHL and UCL were the most useful measurements for estimating the size and biomass of O. variabilis. The relationships among beak measurements and body length (either ML or TL) were not significantly different between two sexes; while those among several beak measurements (UHL, LHL and LBW) and body weight (W) were sexually different. Since male individuals of this species have a slightly greater body weight distribution than female individuals, the body weight was not an appropriate measurement for estimating size and biomass, especially when the sex of individuals in the stomachs of predators was unknown. These relationships provided essential information for future use in size and biomass estimation of O. variabilis, as well as the estimation of predator/prey size ratios in the diet of top predators.

Electronic structure modeling of InAs/GaSb superlattices with hybrid density functional theory

NASA Astrophysics Data System (ADS)

Garwood, T.; Modine, N. A.; Krishna, S.

2017-03-01

The application of first-principles calculations holds promise for greatly improving our understanding of semiconductor superlattices. Developing a procedure to accurately predict band gaps using hybrid density functional theory lays the groundwork for future studies investigating more nuanced properties of these structures. Our approach allows a priori prediction of the properties of SLS structures using only the band gaps of the constituent materials. Furthermore, it should enable direct investigation of the effects of interface structure, e.g., intermixing or ordering at the interface, on SLS properties. In this paper, we present band gap data for various InAs/GaSb type-II superlattice structures calculated using the generalized Kohn-Sham formulation of density functional theory. A PBE0-type hybrid functional was used, and the portion of the exact exchange was tuned to fit the band gaps of the binary compounds InAs and GaSb with the best agreement to bulk experimental values obtained with 18% of the exact exchange. The heterostructures considered in this study are 6 monolayer (ML) InAs/6 ML GaSb, 8 ML InAs/8 ML GaSb and 10 ML InAs/10 ML GaSb with deviations from the experimental band gaps ranging from 3% to 11%.

Percutaneous ethanol injection of large autonomous hyperfunctioning thyroid nodules.

PubMed

Tarantino, L; Giorgio, A; Mariniello, N; de Stefano, G; Perrotta, A; Aloisio, V; Tamasi, S; Forestieri, M C; Esposito, F; Esposito, F; Finizia, L; Voza, A

2000-01-01

To verify the effectiveness of percutaneous ethanol injection (PEI) in the treatment of large (>30-mL) hyperfunctioning thyroid nodules. Twelve patients (eight women, four men; age range, 26-76 years) with a large hyperfunctioning thyroid nodule (volume range, 33-90 mL; mean, 46.08 mL) underwent PEI treatment under ultrasonographic (US) guidance. US was used to calculate the volume of the nodules and to assess the diffusion of the ethanol in the lesions during the procedure. When incomplete necrosis of the nodule was depicted at scintigraphy performed 3 months after treatment, additional PEI sessions were performed. Four to 11 PEI sessions (mean, seven) were performed in each patient, with an injection of 3-14 mL of 99.8% ethanol per session (total amount of ethanol per patient, 30-108 mL; mean, 48.5 mL). At scintigraphy after treatment in all patients, recovery of extranodular uptake, absence of uptake in the nodule, and normalization of thyroid-stimulating hormone (thyrotropin) levels were observed. In all patients, US showed volume reductions of 30%-50% after 3 months and 40%-80% after 6-9 months. Side effects were self-limiting in all patients. During the 6-48-month follow-up, no recurrence was observed. PEI is an effective and safe technique for the treatment of large hyperfunctioning thyroid nodules.

Electronic structure modeling of InAs/GaSb superlattices with hybrid density functional theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Garwood, Tristan; Modine, Normand A.; Krishna, S.

2016-12-18

The application of first-principles calculations holds promise for greatly improving our understanding of semiconductor superlattices. By developing a procedure to accurately predict band gaps using hybrid density functional theory, it lays the groundwork for future studies investigating more nuanced properties of these structures. Our approach allows a priori prediction of the properties of SLS structures using only the band gaps of the constituent materials. Furthermore, it should enable direct investigation of the effects of interface structure, e.g., intermixing or ordering at the interface, on SLS properties. In this paper, we present band gap data for various InAs/GaSb type-II superlattice structuresmore » calculated using the generalized Kohn-Sham formulation of density functional theory. A PBE0-type hybrid functional was used, and the portion of the exact exchange was tuned to fit the band gaps of the binary compounds InAs and GaSb with the best agreement to bulk experimental values obtained with 18% of the exact exchange. The heterostructures considered in this study are 6 monolayer (ML) InAs/6 ML GaSb, 8 ML InAs/8 ML GaSb and 10 ML InAs/10 ML GaSb with deviations from the experimental band gaps ranging from 3% to 11%.« less

Evaluation of anti-microbial activity of spore powder of Ganoderma lucidum on clinical isolates of Prevotella intermedia: A pilot study.

PubMed

Nayak, Ranganath N; Dixitraj, P T; Nayak, Aarati; Bhat, Kishore

2015-09-01

This study aimed at evaluating the anti-microbial activity of spore powder of Ganoderma lucidum on Prevotella intermedia isolated from subgingival plaque from chronic periodontitis patients. Written informed consent was obtained from each subject enrolled in the study. The Institutional Ethics Committee granted the ethical clearance for the study. This study included 20 patients diagnosed with chronic periodontitis. Pooled subgingival plaque samples were collected using sterile curettes from the deepest sites of periodontal pockets. The collected samples were then transported in 1 mL of reduced transport fluid. The organisms were cultured and confirmed. These organisms were then used for minimum inhibitory concentration (MIC) procedure. Mean of the MIC value obtained was calculated. Thirteen out of the 20 clinical samples were tested that showed sensitivity at various concentrations. Five samples showed sensitivity at all concentrations. Twelve samples showed sensitivity at 8 mcg/ml. Eleven samples showed sensitivity at 4 mcg/ml, 8 samples showed sensitivity at 2 mcg/ml, and 5 samples showed sensitivity even at 1 mcg/ml. Mean MIC value of G. lucidum spore powder for P. intermedia obtained was 3.62 mcg/ml. G. lucidum with its multipotential bioactivity could be used as an anti-microbial, in conjunction with conventional therapy in periodontal disease.

Feasibility study of the RenalGuard™ balanced hydration system: a novel strategy for the prevention of contrast-induced nephropathy in high risk patients.

PubMed

Dorval, Jean-Francois; Dixon, Simon R; Zelman, Richard B; Davidson, Charles J; Rudko, Robert; Resnic, Frederic S

2013-06-20

Contrast-induced nephropathy (CIN) is a frequent complication following angiographic procedures with significant impact on healthcare costs, and long-term outcomes. Multiple reno-protective strategies have been studied but few have shown benefit in prospective randomized studies beyond limiting the exposure to iodinated contrast and adequate intravenous. We studied the performance and safety of a novel system designed to achieve precise real-time high volume fluid balance using a closed loop hydration monitoring and infusion system. This prospective, multi-center, FDA approved phase II feasibility study was designed to evaluate the safety and the performance of the RenalGuard matched hydration system. Between October 2006 and November 2007, twenty-three subjects at high risk for CIN (with an estimated glomerular filtration rate (eGFR)<50ml/min/1.73m(2)) undergoing diagnostic or therapeutic catheterization were treated with the system. The primary endpoint of the study was defined as the ability of the system to effectively dynamically match fluid administration to urine output. The 23 subjects at high risk for CIN enrolled had a mean±SD eGFR of 39±9.3. Patients achieved an hourly urine flow rate of 620±400ml/h. The system had a mean effectiveness rate of 99.9% over the duration of therapy with an average saline volume infused of 3825ml closely matched, minute to minute, to urine output of 3579ml. There were no major device-related complications from the experimental therapy, though one patient developed hypokalemia requiring replacement. Two subjects (9.5%) developed CIN as defined by >0.5mg/dl or >25% rise in serum creatinine at 48-60h post contrast administration when compared with the baseline. The study confirmed that the RenalGuard(TM) system is safe and dynamically balances volume hydration with urine production. Further randomized studies are needed to confirm the efficacy of the system in reducing the incidence of CIN. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

The use of oral sucrose for procedural pain relief in infants up to six months of age: a randomized controlled trial.

PubMed

Wilson, Sally; Bremner, Alexandra P; Mathews, Judy; Pearson, Diane

2013-12-01

The aim of this study was to evaluate the effectiveness of oral sucrose in decreasing pain during minor procedures in infants of 1-6 months corrected age. A blinded randomized controlled trial with infants aged 4-26 weeks who underwent venipuncture, heel lance or intravenous cannulation were stratified by corrected age into > 4-12 weeks and > 12-26 weeks. They received 2 mL of either 25% sucrose or sterile water orally 2 minutes before the painful procedure. Nonnutritional sucking and parental comfort, provided in adherence to hospital guidelines, were recorded. Pain behavior was recorded using a validated 10 point scale at baseline, during and following the procedure. Data collectors were blinded to the intervention. A total of 21 and 20 infants received sucrose and water, respectively, in the > 4-12-week age group, and 21 and 22, respectively, in the > 12-26-week age group. No statistical differences were found in pain scores between treatment and control groups at any data collection points in either age group. Infants aged > 4-12 weeks who did nonnutritional sucking showed statistically significantly lower median pain scores at 1, 2, and 3 minutes after the procedure than those who did not suck. Infants aged > 4-26 weeks exhibited pain behavior scores that indicated moderate to large pain during painful procedures; however, there was insufficient evidence to show that 2 mL 25% sucrose had a statistically significant effect in decreasing pain. Infants should be offered nonnutritional sucking in compliance with the Baby Friendly Health Initiative during painful procedures. Crown Copyright © 2013. Published by Elsevier Inc. All rights reserved.

Use of 0.5% bupivacaine with buprenorphine in minor oral surgical procedures.

PubMed

Nagpal, Varun; Kaur, Tejinder; Kapila, Sarika; Bhullar, Ramandeep Singh; Dhawan, Amit; Kaur, Yashmeet

2017-01-01

Minor oral surgical procedures are the most commonly performed procedures by oral and maxillofacial surgeons. Performance of painless surgical procedure is highly appreciated by the patients and is possible through the use of local anesthesia, conscious sedation or general anesthesia. Postoperative pain can also be controlled by the use of opioids, as opioid receptors exist in the peripheral nervous system and offers the possibility of providing postoperative analgesia in the surgical patient. The present study compares the efficacy of 0.5% bupivacaine versus 0.5% bupivacaine with 0.3 mg buprenorphine in minor oral surgical procedures. The present study was conducted in 50 patients who required minor oral surgical procedures under local anesthesia. Two types of local anesthetic solutions were used- 0.5% bupivacaine with 1:200000 epinephrine in group I and a mixture of 39 ml of 0.5% bupivacaine with epinephrine 1:200000 and 1 ml of 300 μg buprenorphine (3 μg/kg)in group II. Intraoperative and postoperative evaluation was carried out for both the anesthetic solutions. The mean duration of postoperative analgesia in bupivacaine group (508.92 ± 63.30 minutes) was quite less than the buprenorphine combination group (1840.84 ± 819.51 minutes). The mean dose of postoperative analgesic medication in bupivacaine group (1.64 ± 0.99 tablets) was higher than buprenorphine combination group (0.80 ± 1.08 tablets). There was no significant difference between the two groups regarding the onset of action of the anesthetic effect and duration of anesthesia. Buprenorphine can be used in combination with bupivacaine for patients undergoing minor oral surgical procedures to provide postoperative analgesia for a longer duration.

Primitive Saltmaking and Marine Science Education.

ERIC Educational Resources Information Center

Spence, Lundie; Copeland, B. J.

1985-01-01

Describes the procedures employed to make salt from seawater. Reviews the basic principles of seawater chemistry and discusses the techniques used to measure salinity. Identifies major saltworks locations and indicates the proper conditions needed for solar production of salt. (ML)

Hyperthyroidism as a clinical manifestation of a embryonal carcinoma of the testis.

PubMed

Arrabal-Polo, M A; Jimenez-Pacheco, A; Arrabal-Martin, M; Moreno-Jimenez, J; Gutierrez-Tejero, F; Galisteo-Moya, R; Zuluaga-Gomez, A

2012-01-01

This case report describes a case of hyperthyroidism as manifestation of an embryonal carcinoma, and illustrates the causes that led to it. The case describes a 33-year-old male patient who complained of chest pain, palpitations, mild dyspnoea, and weight loss. Blood analysis reveals high levels of human chorionic gonadotropin (833818 mlU/ml), T3 (16.90 pg/ml), and T4 (7.77 ng/dl), as well as a fall of TSH (0.01 ulU/ml). Physical examination and imaging procedures confirm the occurrence of a left testicular tumour associated with numerous lung, hepatic and retroperitoneal metastases. Treatment with carbimazol and propanolol is established to manage hyperthyroidism, and an urgent orchiectomy is performed; the histologic diagnosis confirms an embryonal carcinoma (organoid type), but the patient died unexpectedly 24 hours later after having suffered sudden dyspnoea, tachypnoea, and tachyarrhythmia. Hyperthyroidism is a rare manifestation of a testicular tumour that should be borne in mind with regard to the patient's symptomatology and HCG levels.

Does MIS Surgery Allow for Shorter Constructs in the Surgical Treatment of Adult Spinal Deformity?

PubMed

Uribe, Juan S; Beckman, Joshua; Mummaneni, Praveen V; Okonkwo, David; Nunley, Pierce; Wang, Michael Y; Mundis, Gregory M; Park, Paul; Eastlack, Robert; Anand, Neel; Kanter, Adam; Lamarca, Frank; Fessler, Richard; Shaffrey, Chris I; Lafage, Virginie; Chou, Dean; Deviren, Vedat

2017-03-01

The length of construct can potentially influence perioperative risks in adult spinal deformity (ASD) surgery. A head-to-head comparison between open and minimally invasive surgery (MIS) techniques for treatment of ASD has yet to be performed. To examine the impact of MIS approaches on construct length and clinical outcomes in comparison to traditional open approaches when treating similar ASD profiles. Two multicenter databases for ASD, 1 involving MIS procedures and the other open procedures, were propensity matched for clinical and radiographic parameters in this observational study. Inclusion criteria were ASD and minimum 2-year follow-up. Independent t -test and chi-square test were used to evaluate and compare outcomes. A total of 1215 patients were identified, with 84 patients matched in each group. Statistical significance was found for mean levels fused (4.8 for circumferential MIS [cMIS] and 10.1 for open), mean interbody fusion levels (3.6 cMIS and 2.4 open), blood loss (estimated blood loss 488 mL cMIS and 1762 mL open), and hospital length of stay (6.7 days cMIS and 9.7 days open). There was no significant difference in preoperative radiographic parameters or postoperative clinical outcomes (Owestry Disability Index and visual analog scale) between groups. There was a significant difference in postoperative lumbar lordosis (43.3° cMIS and 49.8° open) and pelvic incidence-lumbar lordosis correction (10.6° cMIS and 5.2° open) in the open group. There was no significant difference in reoperation rate between the 2 groups. MIS techniques for ASD may reduce construct length, reoperation rates, blood loss, and length of stay without affecting clinical and radiographic outcomes when compared to a similar group of patients treated with open techniques. Copyright © 2017 by the Congress of Neurological Surgeons

A Clinical Comparison of Anterior Cervical Plates Versus Stand-Alone Intervertebral Fusion Devices for Single-Level Anterior Cervical Discectomy and Fusion Procedures.

PubMed

Panchal, Ripul R; Kim, Kee D; Eastlack, Robert; Lopez, John; Clavenna, Andrew; Brooks, Daina M; Joshua, Gita

2017-03-01

To compare radiologic and clinical outcomes, including rates of dysphagia and dysphonia, using a no-profile stand-alone intervertebral spacer with integrated screw fixation versus an anterior cervical plate and spacer construct for single-level anterior cervical discectomy and fusion (ACDF) procedures. This multicenter, randomized, prospective study included 54 patients with degenerative disc disease requiring ACDF at a single level at C3-C7. Twenty-six patients underwent single-level ACDF with stand-alone spacers, and 28 with plate fixation and spacers. Analyses were based on comparison of perioperative outcomes, radiologic and clinical metrics, and incidence of dysphagia and/or dysphonia. Mean patient age was 48.8 ± 10.1years (53.7% female). No significant differences were observed between groups in operative time (101.8 ± 34.4 minutes, 114.4 ± 31.5 minutes), estimated blood loss (44.8 ± 76.5 mL, 82.5 ± 195.1 mL), or length of hospital stay (1.2 ± 0.6 days, 1.3 ± 0.6 days). Mean visual analog scale pain scores and Neck Disability Index scores improved significantly from preoperative to last follow-up (10.8 ± 2.6 months) in both groups (P < 0.05). Mean Voice Handicap Index and Eating Assessment Tool scores improved significantly from discharge to last follow-up in both groups (P < 0.05). From discharge to 6 months, the stand-alone spacers group consistently demonstrated greater improvement in Voice Handicap Index. Preoperative intervertebral disc and neuroforaminal heights increased significantly across treatment groups (P < 0.01), and no cases required surgical revision at index or adjacent levels. Anterior cervical discectomy and fusion with stand-alone spacers resulted in similar clinical and radiologic outcomes as compared with plate and spacers and may help minimize postoperative dysphonia. Copyright © 2016 Elsevier Inc. All rights reserved.

Random placenta margin incision for control hemorrhage during cesarean delivery complicated by complete placenta previa: a prospective cohort study.

PubMed

Fan, Dazhi; Wu, Shuzhen; Ye, Shaoxin; Wang, Wen; Wang, Lijuan; Fu, Yao; Zeng, Meng; Liu, Yan; Guo, Xiaoling; Liu, Zhengping

2018-04-03

Complete placenta previa (CPP) is one of the most problematic types of abnormal placenta, which is further complicated by placenta accreta or percreta that can unexpectedly lead to catastrophic blood loss, infection, multiple complications, emergency hysterectomy, and even death. The present study aimed to assess the efficacy of random placenta margin incision in controlling intraoperative and total blood loss during cesarean section for CPP women. A prospective cohort study, including a total of 100 consecutive pregnant women with CPP, was performed at a tertiary university-affiliated medical center between March 2016 and July 2017. All of them underwent random placenta margin incision, and intraoperative and total blood loss were analyzed. Through antenatal diagnosis using color Doppler, women were further divided into abnormally invasive placenta (AIP) and non-AIP groups, and anterior and posterior placenta groups. The protocol was registered with the Clinical Trial Registry under registration number NCT02695069. Mean maternal age and gestational age at delivery were 32.26 ± 5.03 years old and 36.21 ± 2.07 weeks, respectively. Total duration of the surgical procedure time was 52.50 (42.43-64.00) min. Median estimated intraoperation blood loss was 746.43 (544.44-1092.86) ml. Total blood loss was 875.00 (604.50-1196.67) ml, and 38 (38.0%) had post-partum hemorrhage. The change from baseline in the median hemoglobin level was -0.33 (6.00-13.20). No women underwent hysterectomy due to massive hemorrhage during the study period. No women had an intraoperative urinary bladder injury, postoperative wound infection, and required relaparotomy, owing to intra-abdominal bleeding. The median hospitalization time was 5.41 (4.18-7.58) d. The random placenta margin incision may be a potentially valuable surgical procedure to control the volumes of intraoperative and postoperative blood loss and reduce the incidence of postpartum hemorrhage among women with complete placenta previa.

Safety, feasibility and complications during resective pediatric epilepsy surgery: a retrospective analysis

PubMed Central

2014-01-01

Background Resective epilepsy surgery is an established and effective method to reduce seizure burden in drug-resistant epilepsy. It was the objective of this study to assess intraoperative blood loss, transfusion requirements and the degree of hypothermia of pediatric epilepsy surgery in our center. Methods Patients were identified by our epilepsy surgery database, and data were collected via retrospective chart review over the past 25 years. Patients up to the age of 6 years were included, and patients with insufficient data were excluded. Results Forty-five patients with an age of 3.2 ± 1.6 (mean ± SD) years and a body weight of 17 [14; 21.5] kg (median [25%, 75% percentile]) were analysed. Duration of surgery was 3 h 49 min ± 53 min, which was accompanied by an intraoperative blood loss of 150 [90; 300] ml. This corresponded to 11.7 [5.2; 21.4] % of estimated total blood volume, ranging from 0 to 75%. A minimal haemoglobin count of 8.8 ± 1.4 g/dl was measured, which was substituted with erythrocyte concentrate (100 [0; 250] ml) in 23 patients. Body core temperature dropped from 36.0 ± 0.7°C at baseline to a minimum of 35.7 ± 0.7°C, and increased significantly (p < 0.001) thereafter to 37.1 ± 0.7°C until the end of surgery. A significant (p = 0.0003) correlation between duration of surgery and blood loss (Pearson r = 0.52) was observed. However, age, minimal body temperature or number of antiepileptic drugs seemed to have no impact on blood loss. Conclusion Resective epilepsy surgery is a safe procedure even in the pediatric population, however it is associated with significant blood loss especially during long surgical procedures. PMID:25157215

Comparison of macronutrient contents in human milk measured using mid-infrared human milk analyser in a field study vs. chemical reference methods.

PubMed

Zhu, Mei; Yang, Zhenyu; Ren, Yiping; Duan, Yifan; Gao, Huiyu; Liu, Biao; Ye, Wenhui; Wang, Jie; Yin, Shian

2017-01-01

Macronutrient contents in human milk are the common basis for estimating these nutrient requirements for both infants and lactating women. A mid-infrared human milk analyser (HMA, Miris, Sweden) was recently developed for determining macronutrient levels. The purpose of the study is to compare the accuracy and precision of HMA method with fresh milk samples in the field studies with chemical methods with frozen samples in the lab. Full breast milk was collected using electric pumps and fresh milk was analyzed in the field studies using HMA. All human milk samples were thawed and analyzed with chemical reference methods in the lab. The protein, fat and total solid levels were significantly correlated between the two methods and the correlation coefficient was 0.88, 0.93 and 0.78, respectively (p  <  0.001). The mean protein content was significantly lower and the mean fat level was significantly greater when measured using HMA method (1.0 g 100 mL -1 vs 1.2 g 100 mL -1 and 3. 7 g 100 mL -1 vs 3.2 g 100 mL -1 , respectively, p  <  0.001). Thus, linear recalibration could be used to improve mean estimation for both protein and fat. There was no significant correlation for lactose between the two methods (p  >  0.05). There was no statistically significant difference in the mean total solid concentration (12.2 g 100 mL -1 vs 12.3 g 100 mL -1 , p  >  0.05). Overall, HMA might be used to analyze macronutrients in fresh human milk with acceptable accuracy and precision after recalibrating fat and protein levels of field samples. © 2016 John Wiley & Sons Ltd.

An instrumental variable approach finds no associated harm or benefit from early dialysis initiation in the United States

PubMed Central

Scialla, Julia J.; Liu, Jiannong; Crews, Deidra C.; Guo, Haifeng; Bandeen-Roche, Karen; Ephraim, Patti L.; Tangri, Navdeep; Sozio, Stephen M.; Shafi, Tariq; Miskulin, Dana C.; Michels, Wieneke M.; Jaar, Bernard G.; Wu, Albert W.; Powe, Neil R.; Boulware, L. Ebony

2014-01-01

The estimated glomerular filtration rate (eGFR) at dialysis initiation has been rising. Observational studies suggest harm, but may be confounded by unmeasured factors. As instrumental variable methods may be less biased we performed a retrospective cohort study of 310,932 patients starting dialysis between 2006 to 2008 and registered in the United States Renal Data System in order to describe geographic variation in eGFR at dialysis initiation and determine its association with mortality. Patients were grouped into 804 health service areas by zip code. Individual eGFR at dialysis initiation averaged 10.8 ml/min/1.73m2 but varied geographically. Only 11% of the variation in mean health service areas-level eGFR at dialysis initiation was accounted for by patient characteristics. We calculated demographic-adjusted mean eGFR at dialysis initiation in the health service areas using the 2006 and 2007 incident cohort as our instrument and estimated the association between individual eGFR at dialysis initiation and mortality in the 2008 incident cohort using the 2 stage residual inclusion method. Among 89,547 patients starting dialysis in 2008 with eGFR 5 to 20 ml/min/1.73m2, eGFR at initiation was not associated with mortality over a median of 15.5 months [hazard ratio 1.025 per 1 ml/min/1.73m2 for eGFR 5 to 14 ml/min/1.73m2; and 0.973 per 1 ml/min/1.73m2 for eGFR 14 to 20 ml/min/1.73m2]. Thus, there was no associated harm or benefit from early dialysis initiation in the United States. PMID:24786707

A Systematic Procedure for Calculating the Average Illuminance on a Work Plane from Skylights Located in a Pitched Roof.

DTIC Science & Technology

1982-05-01

MAY 82 4 B MURDOCH, J E NETTLETON NB2BB3-BI-mR-307 UNCLASSIFIED CEL-CR-BZ.022 ML * CR 82.022’ NAVAL CIVIL ENGINEERING LABORATORY, Porn Hucaeme...procedure All necessary tables’and equations~are included. [ T)A ist DD 47 £,’O ’OfSOLT Unclassi fied SICLUIRTY CL A S,FCATION OF ?..I P&.%n Dog

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tamaki, N.; Alpert, N.M.; Rabito, C.A.

The sequence and magnitude of acute changes in renal blood flow following administration of captopril were determined in a canine model of acute unilateral renal artery stenosis using rubidium-82 and positron emission tomography. Data were recorded in each of nine dogs under three conditions: 1) during a baseline control interval, 2) during renal artery stenosis, and 3) during stenosis with intravenous injection of captopril (1.2 mg/kg). Mean arterial blood pressure was 108 +/- 12 mm Hg at control, increased significantly to 125 +/- 13 mm Hg (p less than 0.01) during stenosis, and decreased to 98 +/- 13 mm/Hg (pmore » less than 0.01) after captopril infusion. Mean renal blood flow was calculated using a steady state single compartment model from the images produced by positron emission tomography. The estimated flow to the affected kidney was 3.37 +/- 1.48 ml/min/g at control, 0.86 +/- 0.62 ml/min/g during stenosis (p less than 0.01), and 0.64 +/- 0.57 ml/min/g after captopril administration (p = NS compared with precaptopril value). The estimated flow to the contralateral kidney was minimally reduced from a baseline of 3.84 +/- 0.95 to 3.24 +/- 1.13 ml/min/g (p = NS) during stenosis and increased after captopril infusion (4.08 +/- 0.94 ml/min/g; p = 0.01). These data suggest that repetitive imaging with positron emission tomography can be used to delineate acute changes in renal perfusion following captopril administration.« less

Estimation of protective levels of anti-O-specific lipopolysaccharide immunoglobulin G antibody against experimental Escherichia coli infection.

PubMed

Schiff, D E; Wass, C A; Cryz, S J; Cross, A S; Kim, K S

1993-03-01

Serum obtained after immunization with an O18 polysaccharide-toxin A conjugate vaccine was evaluated for the estimation of protective levels of anti-O-specific lipopolysaccharide (LPS) immunoglobulin G (IgG) antibody against bacteremia and death caused by a homologous serotype of Escherichia coli K1 strains. Passive transfer of rabbit serum conferred significant protection from a lethal E. coli infection in a neonatal rat model. The overall incidence of bacteremia and mortality was 4% in rat pups receiving undiluted postvaccination serum, while that in control animals was 100% (P < 0.001). The overall incidences of bacteremia were 5 and 72% for animals with serum anti-O18 LPS IgG concentrations of > 1.0 and < 1.0 microgram/ml, respectively, while the overall incidences of mortality for animals with serum anti-O18 LPS IgG levels of > 1.0 and < 1.0 microgram/ml were 0 and 72%, respectively (P < 0.001). Protection against E. coli infection was also demonstrated with human anti-O18 polysaccharide IgG. None of the animals with human anti-O18 LPS IgG levels of > 1 microgram/ml had bacteremia after bacterial challenge, whereas all animals with bacteremia at 18 h had levels of < 1 microgram/ml. These findings suggest that serum anti-O18 LPS IgG concentrations of > 1.0 microgram/ml may provide protection against bacteremia and death caused by a homologous E. coli K1 infection.

USE OF COLLOIDAL RADIOGOLD FOR PREOPERATIVE INTERSTITIAL PREIRRADIATION OF BREAST CANCERS (in German)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mueller, J.H.

1963-01-01

Treatment of early breast cancers by infiltration of the entire parasternal region, the subclavicular area, and the inframammary region with an average of 110 mC of colloidal radiogold dissolved in 140 ml or physiological saline and given in 12 to 14 injections, has proven advantageous. Fourteen days after this treatment a radical mastectomy is performed, followed by postoperative radiation treatment (200 to 400 kv). In 25 patients treated consistently by this procedure 46% of the beta doses to lymph nodes from Au/sup 198/ amounted to more than 5000 r, and an additional 27% received from 1000 to 5000 r. Takingmore » into account the gamma radiation from this isotope, which probably amounts to 2000 r, it is estimated that at least 70% received a therapeutically effective dose to the lymph nodes. Distribution of the radiogold in the lymph nodes has been confirmed histologically, by autoradiographs, and by neutron activation analysis. In 40 patients previously treated by this procedure, who either had no metastases or only a few in the axillary lymph nodes, no recurrence has been noted in the past 10 years. In three patients who died there was evidence of massive neoplasia (carcinomatous mastitis), extensively axillary lymph node involvement, and latent preoperative hematological symptoms. This procedure is not intended to replace classical methods of treatment, but it represents an important advance in treatment of early breast cancer. (BBB)« less

Standardization and validation of a new atomic absorption spectroscopy technique for determination and quantitation of aluminium adjuvant in immunobiologicals.

PubMed

Mishra, Arti; Bhalla, Sumir Rai; Rawat, Sameera; Bansal, Vivek; Sehgal, Rakesh; Kumar, Sunil

2007-10-01

In the present study, Aluminium quantification in immunobiologicals has been described using atomic absorption spectroscopy (AAS) technique. The assay was found to be linear in 25-125 microg/ml Aluminium range. The procedure was found to be accurate for different vaccines with recoveries of external additions ranging between 93.26 and 103.41%. The mean Limit of Variation (L.V.) for both intra- and inter-assay precision was calculated to be 1.62 and 2.22%, respectively. Further the procedure was found to be robust in relation to digestion temperature, alteration in acid (HNO(3) and H(2)SO(4)) ratio used for sample digestion and storage of digested vaccine samples up to a period of 15 days. After validation, AAS method was compared for its equivalency with routinely used complexometric titration method. On simultaneously applying on seven different groups of both bacterial and viral vaccines, viz., DPT, DT, TT, Hepatitis-A and B, Antirabies vaccine (cell culture) and tetravalent DPT-Hib, a high degree of positive correlation (+0.85-0.998) among AAS and titration methods was observed. Further AAS method was found to have an edge over complexometric titration method that a group of vaccines, viz., ARV (cell culture, adsorbed) and Hepatitis-A, in which Aluminium estimation is not feasible by pharmacopoeial approved complexometric titration method (possibly due to some interference in the sample matrix), this newly described and validated AAS assay procedure delivered accurate and reproducible results.

A modified intranasal endoscopic excision for nasal vestibular cyst in China.

PubMed

Huang, Zizhen; Li, Jingjia; Yang, Qintai; Li, Peng; Ye, Jin; Liu, Xian; Zhang, Gehua

2015-03-01

This study aimed to improve the surgical removal procedure for nasal vestibular cysts. Twenty-three patients with nasal vestibular cysts underwent surgical removal of the cyst via a transoral sublabial approach and another 30 patients via a modified intranasal endoscopic excision method. The 30 patients were treated with local anesthesia and the roof of the cyst, which was firmly attached to the mucous membrane of the anterior floor of the nasal cavity, was removed transnasally with microdebrider. Bleeding of the opening was stopped by electric coagulation without nasal packing. Among the 30 consecutive patients who underwent the modified surgical procedure, all patients were successfully treated. The mean duration of surgery was 5.7 ± 2.6 min. The mean estimated blood loss was 3.5 ± 2.1 ml. All patients were outpatients. The mean hospital stay was 1 h. The mean total cost was 140. The visual analog scale scores of postoperative pain, pressure and nasal obstruction were 1, 0 and 1, respectively. The incidence rate of postoperative lip swelling or numbness was 0 %. Postoperative endoscopic findings revealed that the cyst was replaced by an air-containing sinus with a persistent opening at the anterolateral nasal floor. There was no recurrence during a mean follow-up of 18 months. The modified intranasal endoscopic excision is a simple, less invasive, low-cost and effective surgical procedure for the treatment of nasal vestibular cysts. It might change the pattern of treatment for nasal vestibular cysts in China.

In vitro activities of the new semisynthetic glycopeptide telavancin (TD-6424), vancomycin, daptomycin, linezolid, and four comparator agents against anaerobic gram-positive species and Corynebacterium spp.

PubMed

Goldstein, Ellie J C; Citron, Diane M; Merriam, C Vreni; Warren, Yumi A; Tyrrell, Kerin L; Fernandez, Helen T

2004-06-01

Telavancin is a new semisynthetic glycopeptide anti-infective with multiple mechanisms of action, including inhibition of bacterial membrane phospholipid synthesis and inhibition of bacterial cell wall synthesis. We determined the in vitro activities of telavancin, vancomycin, daptomycin, linezolid, quinupristin-dalfopristin, imipenem, piperacillin-tazobactam, and ampicillin against 268 clinical isolates of anaerobic gram-positive organisms and 31 Corynebacterium strains using agar dilution methods according to National Committee for Clinical Laboratory Standards procedures. Plates with daptomycin were supplemented with Ca(2+) to 50 mg/liter. The MICs at which 90% of isolates tested were inhibited (MIC(90)s) for telavancin and vancomycin were as follows: Actinomyces spp. (n = 45), 0.25 and 1 microg/ml, respectively; Clostridium difficile (n = 14), 0.25 and 1 microg/ml, respectively; Clostridium ramosum (n = 16), 1 and 4 microg/ml, respectively; Clostridium innocuum (n = 15), 4 and 16 microg/ml, respectively; Clostridium clostridioforme (n = 15), 8 and 1 microg/ml, respectively; Eubacterium group (n = 33), 0.25 and 2 microg/ml, respectively; Lactobacillus spp. (n = 26), 0.5 and 4 microg/ml, respectively; Propionibacterium spp. (n = 34), 0.125 and 0.5 microg/ml, respectively; Peptostreptococcus spp. (n = 52), 0.125 and 0.5 microg/ml, respectively; and Corynebacterium spp. (n = 31), 0.03 and 0.5 microg/ml, respectively. The activity of TD-6424 was similar to that of quinupristin-dalfopristin for most strains except C. clostridioforme and Lactobacillus casei, where quinupristin-dalfopristin was three- to fivefold more active. Daptomycin had decreased activity (MIC > 4 microg/ml) against 14 strains of Actinomyces spp. and all C. ramosum, Eubacterium lentum, and Lactobacillus plantarum strains. Linezolid showed decreased activity (MIC > 4 microg/ml) against C. ramosum, two strains of C. difficile, and 15 strains of Lactobacillus spp. Imipenem and piperacillin-tazobactam were active against >98% of strains. The MICs of ampicillin for eight Clostridium spp. and three strains of L. casei were >1 microg/ml. The MIC(90) of TD-6424 for all strains tested was

A Comparison of Pseudo-Maximum Likelihood and Asymptotically Distribution-Free Dynamic Factor Analysis Parameter Estimation in Fitting Covariance Structure Models to Block-Toeplitz Matrices Representing Single-Subject Multivariate Time-Series.

ERIC Educational Resources Information Center

Molenaar, Peter C. M.; Nesselroade, John R.

1998-01-01

Pseudo-Maximum Likelihood (p-ML) and Asymptotically Distribution Free (ADF) estimation methods for estimating dynamic factor model parameters within a covariance structure framework were compared through a Monte Carlo simulation. Both methods appear to give consistent model parameter estimates, but only ADF gives standard errors and chi-square…

How the 2SLS/IV estimator can handle equality constraints in structural equation models: a system-of-equations approach.

PubMed

Nestler, Steffen

2014-05-01

Parameters in structural equation models are typically estimated using the maximum likelihood (ML) approach. Bollen (1996) proposed an alternative non-iterative, equation-by-equation estimator that uses instrumental variables. Although this two-stage least squares/instrumental variables (2SLS/IV) estimator has good statistical properties, one problem with its application is that parameter equality constraints cannot be imposed. This paper presents a mathematical solution to this problem that is based on an extension of the 2SLS/IV approach to a system of equations. We present an example in which our approach was used to examine strong longitudinal measurement invariance. We also investigated the new approach in a simulation study that compared it with ML in the examination of the equality of two latent regression coefficients and strong measurement invariance. Overall, the results show that the suggested approach is a useful extension of the original 2SLS/IV estimator and allows for the effective handling of equality constraints in structural equation models. © 2013 The British Psychological Society.

Lung function changes in coke oven workers during 12 years of follow up

PubMed Central

Wu, J; Griffiths, D; Kreis, I; Darling, C

2004-01-01

Aims: To investigate the effect of exposure to coke oven emissions on the lung function of coke oven workers. Methods: The study population, followed from 1978 and 1990, was 580 male workers with at least two sets of lung function measurements (FVC, FEV1, FEV1/FVC, and FEF25–75%). An annual rate of change (time slope) for age and height adjusted lung function index was estimated for each subject. This "time slope" was then treated as the response variable in a weighted multiple regression analysis with selected predictors. Results: For all 580 subjects, each year of working in the "operation" group (the most exposed) was found to increase the FVC decline by around 0.7 ml/year (95% CI 0.1 to 1.3 ml/year). After the exclusion of 111 subjects without detailed work history, the above finding was confirmed and each year of exposure in "operation" was also found to increase the FEV1 decline by around 0.8 ml/year (95% CI 0.1 to 1.4 ml/year). Conclusions: These findings are consistent with the results of previous cross-sectional studies. Work duration in the most exposed position in the coke ovens was associated with increased annual decline for FVC and FEV1. The estimated effect of one year of work exposure in "operation" is equivalent, in terms of the reduction in lung function, to an estimated 2.1 pack-years of smoking for FVC and 1.2 pack-years of smoking for FEV1. PMID:15258275

Risks for heart disease and lung cancer from passive smoking by workers in the catering industry.

PubMed

Hedley, Anthony J; McGhee, Sarah M; Repace, James L; Wong, Lai-Chin; Yu, Marcus Y S; Wong, Tze-Wai; Lam, Tai-Hing

2006-04-01

Workers in the catering industry are at greater risk of exposure to secondhand smoke (SHS) when smoke-free workplace policies are not in force. We determined the exposure of catering workers to SHS in Hong Kong and their risk of death from heart disease and lung cancer. Nonsmoking catering workers were provided with screening at their workplaces and at a central clinic. Participants reported workplace, home, and leisure time exposure to SHS. Urinary cotinine was estimated by enzyme immunoassay. Catering facilities were classified into three types: nonsmoking, partially restricted smoking (with nonsmoking areas), and unrestricted smoking. Mean urinary cotinine levels ranged from 3.3 ng/ml in a control group of 16 university staff through 6.4 ng/ml (nonsmoking), 6.1 ng/ml (partially restricted), and 15.9 ng/ml (unrestricted smoking) in 104 workers who had no exposures outside of work. Workers in nonsmoking facilities had exposures to other smoking staff. We modeled workers' mortality risks using average cotinine levels, estimates of workplace respirable particulates, risk data for cancer and heart disease from cohort studies, and national (US) and regional (Hong Kong) mortality for heart disease and lung cancer. We estimated that deaths in the Hong Kong catering workforce of 200,000 occur at the rate of 150 per year for a 40-year working-lifetime exposure to SHS. When compared with the current outdoor air quality standards for particulates in Hong Kong, 30% of workers exceeded the 24-h and 98% exceeded the annual air quality objectives due to workplace SHS exposures.

Reinforcement of high-risk anastomoses using laser-activated protein solders: a clinical study

NASA Astrophysics Data System (ADS)

Libutti, Steven K.; Bessler, Marc; Chabot, J.; Bass, Lawrence S.; Oz, Mehmet C.; Auteri, Joseph S.; Kirsch, Andrew J.; Nowygrod, Roman; Treat, Michael R.

1993-07-01

Anastomotic leakage or breakdown can result in catastrophic complications and significantly increased post-operative morbidity and mortality. Certain anastomoses are subject to a higher incidence of disruption and are therefore termed high risk. In an attempt to decrease the risk of anastomotic leaks, we reinforced sutured anastomoses with a laser activated protein solder in patients undergoing esophagojejunostomies (n equals 2), lung transplantation (n equals 2), and pancreaticojejunostomies (Whipple procedure, n equals 5). The protein solder was composed of 1.0 ml of a 25% human albumin solution, 1.0 ml of sodium hyaluronate, and 0.1 ml of Cardiogreen dye. This composition was applied to the sutured anastomosis and activated with an 860 nm pulsed diode laser. Drains were placed when appropriate and patients were followed for up to 10 months post-operatively and assessed for clinical signs of anastomotic leaks. Results to data demonstrated that there were no immediate complications as a result of the procedure. Operative time was not significantly lengthened. There were no cases of clinically significant leakage from any of the reinforced anastomoses. Laser activated protein solders may help to reduce the incidence of leakage in high risk anastomoses. Large numbers of patients and longer follow-up is needed however, to draw significant conclusions.

Relationship between preoperative radial artery and postoperative arteriovenous fistula blood flow in hemodialysis patients.

PubMed

Sato, Michiko; Io, Hiroaki; Tanimoto, Mitsuo; Shimizu, Yoshio; Fukui, Mitsumine; Hamada, Chieko; Horikoshi, Satoshi; Tomino, Yasuhiko

2012-01-01

It is recommended that arteriovenous fistula (AVF) blood flow should be more than 425 ml/min before cannulation. However, the relationship between preoperative radial artery flow (RAF) and postoperative AVF blood flow has still not been examined. Sixty-one patients with end-stage kidney disease (ESKD) were examined. They had an AVF prepared at Juntendo University Hospital from July 2006 through August 2007. Preoperative RAF and postoperative AVF blood flows were measured by ultrasonography. AVF blood flow gradually increased after the operation. AVF blood flow was significantly correlated with preoperative RAF. When preoperative RAF exceeded 21.4 ml/min, AVF blood flow rose to more than 425 ml/min. The postoperative AVF blood flow in the group with RAF of more than 20 ml/min was significantly higher than that in those with less than 20 ml/min. Preoperative RAF of less than 20 ml/min had a significantly high risk of primary AVF failure within 8 months compared with that of more than 20 ml/min. It appears that measurement of RAF by ultrasonography is useful for estimating AVF blood flow postoperatively and can predict the risk of complications in ESKD patients.

Spectrophotometric and spectrofluorimetric methods for analysis of tramadol, acebutolol and dothiepin in pharmaceutical preparations

NASA Astrophysics Data System (ADS)

Abdellatef, Hisham E.; El-Henawee, Magda M.; El-Sayed, Heba M.; Ayad, Magda M.

2006-12-01

Sensitive spectrophotometric and spectrofluorimetric methods are described for the determination of tramadol, acebutolol and dothiepin (dosulepin) hydrochlorides. The two methods are based on the condensation of the cited drugs with the mixed anhydrides of malonic and acetic acids at 60 °C for 25-40 min. The coloured condensation products are suitable for the spectrophotometric and spectrofluorimetric determination at 329-333 and 431-434 nm (excitation at 389 nm), respectively. For the spectrophotometric method, Beer's law was obeyed from 0.5 to 2.5 μg ml -1 for tramadol, dothiepin and 5-25 μg ml -1 for acebutolol. Using the spectrofluorimetric method linearity ranged from 0.25 to 1.25 μg ml -1 for tramadol, dothiepin and 1-5 μg ml -1 for acebutolol. Mean percentage recoveries for the spectrophotometric method were 99.68 ± 1.00, 99.95 ± 1.11 and 99.72 ± 1.01 for tramadol, acebutolol and dothiepin, respectively and for the spectrofluorimetric method, recoveries were 99.5 ± 0.844, 100.32 ± 0.969 and 99.82 ± 1.15 for the three drugs, respectively. The optimum experimental parameters for the reaction has been studied. The validity of the described procedures was assessed. Statistical analysis of the results has been carried out revealing high accuracy and good precision. The proposed methods were successfully applied for the determination of the selected drugs in their pharmaceutical preparations with good recoveries. The procedures were accurate, simple and suitable for quality control application.

Estimating multilevel logistic regression models when the number of clusters is low: a comparison of different statistical software procedures.

PubMed

Austin, Peter C

2010-04-22

Multilevel logistic regression models are increasingly being used to analyze clustered data in medical, public health, epidemiological, and educational research. Procedures for estimating the parameters of such models are available in many statistical software packages. There is currently little evidence on the minimum number of clusters necessary to reliably fit multilevel regression models. We conducted a Monte Carlo study to compare the performance of different statistical software procedures for estimating multilevel logistic regression models when the number of clusters was low. We examined procedures available in BUGS, HLM, R, SAS, and Stata. We found that there were qualitative differences in the performance of different software procedures for estimating multilevel logistic models when the number of clusters was low. Among the likelihood-based procedures, estimation methods based on adaptive Gauss-Hermite approximations to the likelihood (glmer in R and xtlogit in Stata) or adaptive Gaussian quadrature (Proc NLMIXED in SAS) tended to have superior performance for estimating variance components when the number of clusters was small, compared to software procedures based on penalized quasi-likelihood. However, only Bayesian estimation with BUGS allowed for accurate estimation of variance components when there were fewer than 10 clusters. For all statistical software procedures, estimation of variance components tended to be poor when there were only five subjects per cluster, regardless of the number of clusters.

Randomized trial of one-hour sodium bicarbonate vs standard periprocedural saline hydration in chronic kidney disease patients undergoing cardiovascular contrast procedures

PubMed Central

de Vries, Jean-Paul P. M.; Van der Heyden, Jan; Sijpkens, Yvo W. J.; van Dijkman, Paul R. M.; Wever, Jan J.; van Overhagen, Hans; Vahl, Antonie C.; Aarts, Nico; Verberk-Jonkers, Iris J. A. M.; Brulez, Harald F. H.; Hamming, Jaap F.; van der Molen, Aart J.; Cannegieter, Suzanne C.; Putter, Hein; van den Hout, Wilbert B.; Kilicsoy, Inci; Rabelink, Ton J.; Huisman, Menno V.

2018-01-01

Background Guidelines advise periprocedural saline hydration for prevention of contrast induced-acute kidney injury (CI-AKI). We analysed whether 1-hour sodium bicarbonate hydration administered solely prior to intra-arterial contrast exposure is non-inferior to standard periprocedural saline hydration in chronic kidney disease (CKD) patients undergoing elective cardiovascular diagnostic or interventional contrast procedures. Methods We performed an open-label multicentre non-inferiority trial between 2011–2014. Patients were randomized to 1 hour pre-procedure sodium bicarbonate hydration (250 ml 1.4%, N = 168) or 4–12 hours saline hydration (1000 ml 0.9%, N = 165) prior to and following contrast administration (2000 ml of saline total). Primary outcome was the relative serum creatinine increase (%) 48–96 hours post contrast exposure. Secondary outcomes were: incidence of CI-AKI (serum creatinine increase>25% or >44μmol/L), recovery of renal function, the need for dialysis, and hospital costs within two months follow-up. Results Mean relative creatinine increase was 3.1% (95%CI 0.9 to 5.2%) in the bicarbonate and 1.1% (95%CI -1.2 to 3.5%) in the saline arm, mean difference 1.9% (95%CI -1.2 to 5.1%, p-non-inferiority <0.001). CI-AKI occurred in 11 (6.7%) patients randomized to sodium bicarbonate and 12 (7.5%) to saline (p = 0.79). Renal function did not fully recover in 40.0% and 44.4% of CI-AKI patients, respectively (p = 0.84). No patient required dialysis. Mean costs for preventive hydration and clinical preparation for the contrast procedure were $1158 for sodium bicarbonate vs. $1561 for saline (p < 0.001). Conclusion Short hydration with sodium bicarbonate prior to elective cardiovascular diagnostic or therapeutic contrast procedures is non-inferior to standard periprocedural saline hydration in CKD patients with respect to renal safety and results in considerable healthcare savings. Trial registration Netherlands Trial Register (http://www.trialregister.nl/trialreg/index.asp), Nr NTR2699 PMID:29420536

Continuous nasogastric tube feeding: monitoring by combined use of refractometry and traditional gastric residual volumes.

PubMed

Chang, W-K; McClave, S-A; Chao, Y-C

2004-02-01

Traditional use of gastric residual volumes (GRVs) is insensitive and cannot distinguish retained enteral formula from the large volume of endogenous secretions. We designed this prospective study to determine whether refractometry and Brix value (BV) measurements could be used to monitor gastric emptying and tolerance in patients receiving continuous enteral feeding. Thirty-six patients on continuous nasogastric tube feeding were divided into two groups; patients with lower GRVs (<75 ml) in Group 1, patients with higher GRVs (>75 ml) in Group 2. Upon entry, all gastric contents were aspirated, the volume was recorded (Asp GRV), BV measurements were made by refractometry, and then the contents were reinstilled but diluted with 30 ml additional water. Finally, a small amount was reaspirated and repeat BV measurements were made. Three hours later, the entire procedure was repeated a second time. The BV ratio, calculated (Cal) GRV, and volume of formula remaining were calculated by derived equations. Mean BV ratios were significantly higher for those patients in Group 2 compared to those in Group 1. All but one of the 22 patients (95%) in Group 1 had a volume of formula remaining in the stomach estimated on both measurements to be less than the hourly infusion rate (all these patients had BV ratios <70%). In contrast, six of the 14 patients in Group 2 (43%) on both measurements were estimated to have volumes of formula remaining that were greater than the hourly infusion rate (all these patients had BV ratios >70%). Three of the Group 2 patients (21%) whose initial measurement showed evidence for retention of formula, improved on repeat follow-up measurement assuring adequate gastric emptying. The remaining five patients from Group 2 (35%) had a volume of formula remaining that was less than the hourly infusion rate on both measurements. The pattern of Asp GRVs and serial pre- and post-dilution BVs failed to differentiate these patients in Group 2 with potential emptying problems from those with sufficient gastric emptying. Refractometry and measurement of the BV may improve the clinical utilization of GRVs, by its ability to identify the component of formula within gastric contents and track changes in that component related to gastric emptying.

Experimental Procedure for Determination of the Dielectric Properties of Biological Samples in the 2-50 GHz Range

PubMed Central

Odelstad, Elias; Raman, Sujith; Rydberg, Anders

2014-01-01

The objective of this paper was to test and evaluate an experimental procedure for providing data on the complex permittivity of different cell lines in the 2–50-GHz range at room temperature, for the purpose of future dosimetric studies. The complex permittivity measurements were performed on cells suspended in culture medium using an open-ended coaxial probe. Maxwell’s mixture equation then allows the calculation of the permittivity profiles of the cells from the difference in permittivity between the cell suspensions and pure culture medium. The open-ended coaxial probe turned out to be very sensitive to disturbances affecting the measurements, resulting in poor precision. Permittivity differences were not large in relation to the spread of the measurements and repeated measurements were performed to improve statistics. The 95% confidence intervals were computed for the arithmetic means of the measured permittivity differences in order to test the statistical significance. The results showed that for bone cells at the lowest tested concentration (33 500/ml), there were significance in the real part of the permittivity at frequencies above 30 GHz, and no significance in the imaginary part. For the second lowest concentration (67 000/ml) there was no significance at all. For a medium concentration of bone cells (135 000/ml) there was no significance in the real part, but there was significance in the imaginary part at frequencies below about 25 GHz. The cell suspension with a concentration of 1 350 000/ml had significance in the real part for both high (above 30 GHz) and low (below 15 GHz) frequencies. The imaginary part showed significance for frequencies below 25 GHz. In the case of an osteosarcoma cell line with a concentration of 2 700 000/ml, only the imaginary part showed significance, and only for frequencies below 15 GHz. For muscle cells at a concentration of 743 450/ml, there was only significance in the imaginary part for frequencies below 5 GHz. The experimental data indicated that the complex permittivity of the culture medium may be used for modeling of cell suspensions. PMID:27170886

Treatment of Heart Failure With Associated Functional Mitral Regurgitation Using the ARTO System: Initial Results of the First-in-Human MAVERIC Trial (Mitral Valve Repair Clinical Trial).

PubMed

Rogers, Jason H; Thomas, Martyn; Morice, Marie-Claude; Narbute, Inga; Zabunova, Milana; Hovasse, Thomas; Poupineau, Mathieu; Rudzitis, Ainars; Kamzola, Ginta; Zvaigzne, Ligita; Greene, Samantha; Erglis, Andrejs

2015-07-01

MAVERIC (Mitral Valve Repair Clinical Trial) reports the safety and efficacy of the ARTO system in patients with symptomatic heart failure and functional mitral regurgitation (FMR). The ARTO system percutaneously modifies the mitral annulus to improve leaflet coaptation in FMR. The MAVERIC trial is a prospective, nonrandomized first-in-human study. Key inclusion criteria were systolic heart failure New York Heart Association functional classes II to IV, FMR grade ≥2+, left ventricular (LV) ejection fraction ≤40%, LV end-diastolic diameter >50 mm and ≤75 mm. Exclusion criteria were clinical variables that precluded feasibility of the ARTO procedure. Primary outcomes were safety (30-day major adverse events) and efficacy (MR reduction, LV volumes, and functional status). Eleven patients received the ARTO system, and there were no procedural adverse events. From baseline to 30 days, there were meaningful improvements. Effective regurgitant orifice area decreased from 30.3 ± 11.1 mm(2) to 13.5 ± 7.1 mm(2) and regurgitant volumes from 45.4 ± 15.0 ml to 19.5 ± 10.2 ml. LV end-systolic volume index improved from 77.5 ± 24.3 ml/m(2) to 68.5 ± 21.4 ml/m(2), and LV end-diastolic volume index 118.7 ± 28.6 ml/m(2) to 103.9 ± 21.2 ml/m(2). Mitral annular anteroposterior diameter decreased from 45.0 ± 3.3 mm to 38.7 ± 3.0 mm. Functional status was 81.8% New York Heart Association functional class III/IV improving to 54.6% functional class I/II. At 30 days, there were 2 adverse events: 1 pericardial effusion requiring surgical drainage; and 1 asymptomatic device dislodgement. The ARTO system is a novel transcatheter device that can be used safely with meaningful efficacy in the treatment of FMR. (Mitral Valve Repair Clinical Trial [MAVERIC]; NCT02302872). Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

Reproducible computational biology experiments with SED-ML--the Simulation Experiment Description Markup Language.

PubMed

Waltemath, Dagmar; Adams, Richard; Bergmann, Frank T; Hucka, Michael; Kolpakov, Fedor; Miller, Andrew K; Moraru, Ion I; Nickerson, David; Sahle, Sven; Snoep, Jacky L; Le Novère, Nicolas

2011-12-15

The increasing use of computational simulation experiments to inform modern biological research creates new challenges to annotate, archive, share and reproduce such experiments. The recently published Minimum Information About a Simulation Experiment (MIASE) proposes a minimal set of information that should be provided to allow the reproduction of simulation experiments among users and software tools. In this article, we present the Simulation Experiment Description Markup Language (SED-ML). SED-ML encodes in a computer-readable exchange format the information required by MIASE to enable reproduction of simulation experiments. It has been developed as a community project and it is defined in a detailed technical specification and additionally provides an XML schema. The version of SED-ML described in this publication is Level 1 Version 1. It covers the description of the most frequent type of simulation experiments in the area, namely time course simulations. SED-ML documents specify which models to use in an experiment, modifications to apply on the models before using them, which simulation procedures to run on each model, what analysis results to output, and how the results should be presented. These descriptions are independent of the underlying model implementation. SED-ML is a software-independent format for encoding the description of simulation experiments; it is not specific to particular simulation tools. Here, we demonstrate that with the growing software support for SED-ML we can effectively exchange executable simulation descriptions. With SED-ML, software can exchange simulation experiment descriptions, enabling the validation and reuse of simulation experiments in different tools. Authors of papers reporting simulation experiments can make their simulation protocols available for other scientists to reproduce the results. Because SED-ML is agnostic about exact modeling language(s) used, experiments covering models from different fields of research can be accurately described and combined.

Development and validation of a reversed-phase HPLC method for simultaneous estimation of ambroxol hydrochloride and azithromycin in tablet dosage form.

PubMed

Shaikh, K A; Patil, S D; Devkhile, A B

2008-12-15

A simple, precise and accurate reversed-phase liquid chromatographic method has been developed for the simultaneous estimation of ambroxol hydrochloride and azithromycin in tablet formulations. The chromatographic separation was achieved on a Xterra RP18 (250 mm x 4.6 mm, 5 microm) analytical column. A Mixture of acetonitrile-dipotassium phosphate (30 mM) (50:50, v/v) (pH 9.0) was used as the mobile phase, at a flow rate of 1.7 ml/min and detector wavelength at 215 nm. The retention time of ambroxol and azithromycin was found to be 5.0 and 11.5 min, respectively. The validation of the proposed method was carried out for specificity, linearity, accuracy, precision, limit of detection, limit of quantitation and robustness. The linear dynamic ranges were from 30-180 to 250-1500 microg/ml for ambroxol hydrochloride and azithromycin, respectively. The percentage recovery obtained for ambroxol hydrochloride and azithromycin were 99.40 and 99.90%, respectively. Limit of detection and quantification for azithromycin were 0.8 and 2.3 microg/ml, for ambroxol hydrochloride 0.004 and 0.01 microg/ml, respectively. The developed method can be used for routine quality control analysis of titled drugs in combination in tablet formulation.

Isolation and Characterization of a Glycosyl Hydrolase Family 16 β-Agarase from a Mangrove Soil Metagenomic Library

PubMed Central

Mai, Zhimao; Su, Hongfei; Zhang, Si

2016-01-01

A mangrove soil metagenomic library was constructed and a β-agarase gene designated as AgaML was isolated by functional screening. The gene encoded for a 659-amino-acids polypeptide with an estimated molecular mass of 71.6 kDa. The deduced polypeptide sequences of AgaML showed the highest identity of 73% with the glycoside hydrolase family 16 β-agarase from Microbulbifer agarilyticus in the GenBank database. AgaML was cloned and highly expressed in Escherichia coli BL21(DE3). The purified recombinant protein, AgaML, showed optimal activity at 50 °C and pH 7.0. The kinetic parameters of Km and Vmax values toward agarose were 4.6 mg·mL−1 and 967.5 μM·min−1·mg−1, respectively. AgaML hydrolyzed the β-1,4-glycosidic linkages of agar to generate neoagarotetraose (NA4) and neoagarohexaose (NA6) as the main products. These characteristics suggest that AgaML has potential application in cosmetic, pharmaceuticals and food industries. PMID:27548158

Anticipatory Processing in the Brain on the Perception of Müller-Lyer Illusionary Figures—A Brain Potential Study

NASA Astrophysics Data System (ADS)

Nomura, Shusaku; Sasaki, Shuntaro; Hirakawa, Masato; Hiwaki, Osamu

2010-11-01

We investigated the brain potential in relation with the recognition of Müller-Lyer (ML) illusionary figure, which was a famous optical illusion. Although it is frequently assumed that the ML illusionary effect could be derived from its geometrical construction, it derives the same length miss-estimation effect on the sense of touch; haptic illusion. Moreover it occurs in people who are blindfolded or congenital blind. Thus somehow higher information processing than the optical one within the brain could be expected to involve with the recognition of ML figure while few brain studies have demonstrated it. We then investigated the brain waves under subjects' perceiving ML illusionary figure. As a result the marked difference of the brain potential between ML and the control condition around the midline of parietal brain, where the multi-modal perception information was thought to associate within the brain, was observed. This result implies that the anticipatory processing on the perception of ML illusionary figures would be derived by integrating multi-sensory information.

Wine glass size and wine sales: a replication study in two bars.

PubMed

Pechey, Rachel; Couturier, Dominique-Laurent; Hollands, Gareth J; Mantzari, Eleni; Zupan, Zorana; Marteau, Theresa M

2017-08-01

Wine glass size may influence perceived volume and subsequently purchasing and consumption. Using a larger glass to serve the same portions of wine was found to increase wine sales by 9.4% (95% CI 1.9, 17.5) in a recent study conducted in one bar. The current study aimed to replicate this previous work in two other bars using a wider range of glass sizes. To match the previous study, a repeated multiple treatment reversal design, during which wine was served in glasses of the same design but different sizes, was used. The study was conducted in two bars in Cambridge, England, using glass sizes of 300, 370, 510 ml (Bar 1) and 300 and 510 ml (Bar 2). Customers purchased their choice of a 750 ml bottle, or standard UK measures of 125, 175 or 250 ml of wine, each of which was served with the same glass. Bar 1 Daily wine volume (ml) purchased was 10.5% (95% CI 1.0, 20.9) higher when sold in 510 ml compared to 370 ml glasses; but sales were not significantly higher with 370 ml versus 300 ml glasses (6.5%, 95% CI -5.2, 19.6). Bar 2 Findings were inconclusive as to whether daily wine purchased differed when using 510 ml versus 300 ml glasses (-1.1%, 95% CI -12.6, 11.9). These results provide a partial replication of previous work showing that introducing larger glasses (without manipulating portion size) increases purchasing. Understanding the mechanisms by which wine glass size influences consumption may elucidate when the effect can be expected and when not. Trial registration This study is a replication study, based on the procedure set out in the trial registration for the study that it attempts to replicate (ISRCTN registry: ISRCTN12018175).

A comparison of the enzymatic properties of three recombinant isoforms of thrombolytic and antibacterial protein--Destabilase-Lysozyme from medicinal leech.

PubMed

Kurdyumov, Alexey S; Manuvera, Valentin A; Baskova, Isolda P; Lazarev, Vassili N

2015-11-21

Destabilase-Lysozyme (mlDL) is a multifunctional i-type enzyme that has been found in the secretions from the salivary glands of medicinal leeches. mlDL has been shown to exhibit isopeptidase, muramidase and antibacterial activity. This enzyme attracts interest because it expresses thrombolytic activity through isopeptidolysis of the ε-(γ-Glu)-Lys bonds that cross-link polypeptide chains in stabilised fibrin. To date, three isoforms of mlDL have been identified. The enzymatic properties of pure mlDL isoforms have not yet been described because only destabilase complexes containing other proteins could be isolated from the salivary gland secretion and because low product yield from the generation of recombinant proteins has made comprehensive testing difficult. In the present study, we optimised the procedures related to the expression, isolation and purification of active mlDL isoforms (mlDL-Ds1, mlDL-Ds2, mlDL-Ds3) using an Escherichia coli expression system, and we detected and compared their muramidase, lytic, isopeptidase and antimicrobial activities. After optimisation, the product yield was 30 mg per litre of culture. The data obtained in our study led to the suggestion that the recombinant mlDL isoforms isolated from inclusion bodies form stable oligomeric complexes. Analyses of the tested activities revealed that all isoforms exhibited almost identical patterns of pH and ionic strength effects on the activities. We determined that mlDL-Ds1, 2, 3 possessed non-enzymatic antibacterial activity independent of their muramidase activity. For the first time, we demonstrated the fibrinolytic activity of the recombinant mlDL and showed that only intact proteins possessed this activity, suggesting their enzymatic nature. The recombinant Destabilase-Lysozyme isoforms obtained in our study may be considered potential thrombolytic agents that act through a mechanism different from that of common thrombolytics.

Chlamydomonas: A Model Green Plant.

ERIC Educational Resources Information Center

Sheffield, E.

1985-01-01

Discusses the instructional potential of Chlamydomonas in providing a basis for a range of experimental investigations to illustrate basic biological phenomena. Describes the use of this algae genus in studies of population growth, photosynthesis, and mating behavior. Procedures for laboratory exercises are included. (ML)

Magnetic Fluids--Part 2.

ERIC Educational Resources Information Center

Hoon, S. B.; Tanner, B. K.

1985-01-01

Continues a discussion of magnetic fluids by providing background information on and procedures for conducting several demonstrations. Indicates that, with a little patience and ingenuity, only modest magnetic fields and about 20 ml of low-viscosity, commercial magnetite-water-based magnetic fluid are required. (JN)

A Laboratory Experiment of the Purification of Catalase.

ERIC Educational Resources Information Center

Busquets, Montserrat; Franco, Rafael

1986-01-01

Describes a simple method for purifying catalase for the study of proteins. Procedures are systematically and diagramatically presented. Also identifies polyacrylamide gel electrophoresis, kinetic studies, and apparent molecular weight determination as possible techniques to be used in studying proteins. (ML)

40 CFR 98.425 - Procedures for estimating missing data.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 21 2011-07-01 2011-07-01 false Procedures for estimating missing data... estimating missing data. (a) Whenever the quality assurance procedures in § 98.424(a)(1) of this subpart... following missing data procedures shall be followed: (1) A quarterly CO2 mass flow or volumetric flow value...

40 CFR 98.445 - Procedures for estimating missing data.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 21 2011-07-01 2011-07-01 false Procedures for estimating missing data... Procedures for estimating missing data. A complete record of all measured parameters used in the GHG... following missing data procedures: (a) A quarterly flow rate of CO2 received that is missing must be...

40 CFR Appendix C to Part 75 - Missing Data Estimation Procedures

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 17 2013-07-01 2013-07-01 false Missing Data Estimation Procedures C... (CONTINUED) CONTINUOUS EMISSION MONITORING Pt. 75, App. C Appendix C to Part 75—Missing Data Estimation Procedures 1. Parametric Monitoring Procedure for Missing SO2 Concentration or NOX Emission Rate Data 1...

40 CFR 98.425 - Procedures for estimating missing data.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Procedures for estimating missing data... estimating missing data. (a) Whenever the quality assurance procedures in § 98.424(a) of this subpart cannot... following missing data procedures shall be followed: (1) A quarterly CO2 mass flow or volumetric flow value...

40 CFR Appendix C to Part 75 - Missing Data Estimation Procedures

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 17 2014-07-01 2014-07-01 false Missing Data Estimation Procedures C... (CONTINUED) CONTINUOUS EMISSION MONITORING Pt. 75, App. C Appendix C to Part 75—Missing Data Estimation Procedures 1. Parametric Monitoring Procedure for Missing SO2 Concentration or NOX Emission Rate Data 1...

40 CFR Appendix C to Part 75 - Missing Data Estimation Procedures

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 17 2012-07-01 2012-07-01 false Missing Data Estimation Procedures C... (CONTINUED) CONTINUOUS EMISSION MONITORING Pt. 75, App. C Appendix C to Part 75—Missing Data Estimation Procedures 1. Parametric Monitoring Procedure for Missing SO2 Concentration or NOX Emission Rate Data 1...

40 CFR 98.425 - Procedures for estimating missing data.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 21 2014-07-01 2014-07-01 false Procedures for estimating missing data... estimating missing data. (a) Whenever the quality assurance procedures in § 98.424(a)(1) of this subpart... following missing data procedures shall be followed: (1) A quarterly CO2 mass flow or volumetric flow value...

40 CFR 98.425 - Procedures for estimating missing data.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 22 2013-07-01 2013-07-01 false Procedures for estimating missing data... estimating missing data. (a) Whenever the quality assurance procedures in § 98.424(a)(1) of this subpart... following missing data procedures shall be followed: (1) A quarterly CO2 mass flow or volumetric flow value...