Rigorous analysis of the interaction between proteins and low water-solubility drugs by qNMR-aided NMR titration experiments

2021 ◽  
Author(s):  
Takuya Hirakawa ◽  
Erik Walinda ◽  
Daichi Morimoto ◽  
Kenji Sugase
Keyword(s):  
Quantitative Analysis ◽  
Water Solubility ◽  
Accurate Estimation ◽  
Rigorous Analysis ◽  
Nmr Titration ◽  
Target Proteins ◽  
Physicochemical Data

Drugs are designed and validated based on physicochemical data on their interactions with target proteins. For low water- solubility drugs, however, quantitative analysis is practically impossible without accurate estimation of...

scholarly journals Quantitative 166Ho-microspheres SPECT derived from a dual-isotope acquisition with 99mTc-colloid is clinically feasible

2020 ◽  
Author(s):  
Martina Stella ◽  
Arthur J.A.T. Braat ◽  
Marnix G.E.H. Lam ◽  
Hugo W.A.M. de Jong ◽  
Rob van Rooij
Keyword(s):  
Quantitative Analysis ◽  
Scatter Correction ◽  
Absorbed Dose ◽  
Observer Agreement ◽  
Qualitative Assessment ◽  
Accurate Estimation ◽  
P Value ◽  
Dual Isotope ◽  
Compromise Image Quality ◽  
Healthy Liver

Abstract Purpose: Accurate dosimetry is essential in radioembolization. To this purpose, an automatic protocol for healthy liver dosimetry based on dual isotope (DI) SPECT imaging, combining holmium-166 (166Ho)-microspheres and technetium-99m (99mTc)-colloid, was developed: 166Ho-microspheres used as scout and therapeutic particles and 99mTc-colloid to identify the healthy liver. DI SPECT allows for an automatic and accurate estimation of absorbed doses, introducing true personalized dosimetry. However, photon crosstalk between isotopes can compromise image quality. This study investigates the effect of 99mTc downscatter on 166Ho dosimetry, by comparing 166Ho-SPECT reconstructions of patient scans acquired before (166Ho-only) and after additional administration of 99mTc-colloid (166Ho-DI).Methods: The 166Ho-only and 166Ho-DI scans were performed in short succession by injecting 99mTc-colloid on the scanner table. To compensate for 99mTc downscatter, its influence was accounted for in the DI image reconstruction using energy window-based scatter correction methods. The qualitative assessment was performed by independent blinded comparison by two nuclear medicine physicians assessing 65 pairs of SPECT/CT. Inter-observer agreement was tested by Cohen's kappa coefficient. For the quantitative analysis, two volumes of interest within the liver, VOITUMOR and VOIHEALTHY, were manually delineated on the 166Ho-only reconstruction and transferred to the co-registered 166Ho-DI reconstruction. Absorbed dose within the resulting VOIs, and in the lungs (VOILUNGS), was calculated based on the administered therapeutic activity.Results: The qualitative assessment showed no distinct clinical preference for either 166Ho-only or 166Ho-DI SPECT (kappa=0.093). Quantitative analysis indicated that the mean absorbed dose difference between 166Ho-DI and 166Ho-only was -2.00±2.84 Gy (median 27 Gy; p-value<0.00001), -5.27±8.99 Gy (median 116 Gy; p-value =0.00035) and 0.80±1.08 Gy (median 3 Gy; p-value<0.00001) for VOIHEALTHY, VOITUMOR and VOILUNGS respectively. The corresponding Pearson’s correlation coefficient between 166Ho-only and 166Ho-DI for absorbed dose was 0.97, 0.99 and 0.82, respectively.

scholarly journals Quantitative Analysis of Resorcinol from Marketed Hair Tonic Using Liquid Chromatographic Technique

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Amit Kumar De ◽  
Partha Pratim Chowdhury ◽  
Shyamaprasad Chattapadhyay
Keyword(s):  
Stainless Steel ◽  
Quantitative Analysis ◽  
Mobile Phase ◽  
Quantitative Estimation ◽  
Accurate Estimation ◽  
Internal Diameter ◽  
Chromatographic Technique ◽  
Steel Column ◽  
Stainless Steel Column ◽  
Liquid Chromatographic

Quantitative estimation of resorcinol from marketed pharmaceutical formulation has been reported in this study. Resorcinol as a pharmaceutical ingredient has a broad spectrum of application but its application is limited due to its toxic side effects. Method for the accurate estimation of resorcinol is therefore essential. In the current study we have developed a chromatographic technique for its estimation from a marketed hair tonic meant for the treatment of several dermatological diseases of the scalp. A stainless steel column 25 cm in length and 4 mm internal diameter packed with octadecylsilane (5 µm) was used for this purpose. The mobile phase was a mixture of phosphate buffer of pH 2.8 and acetonitrile. The flow rate was 0.6 mL·min−1 and the detection wavelength was 280 nm. The method was found to be linear between concentration range 10.28 µg·mL−1 to 71.96 µg·mL−1 with r2 value 0.999. The accuracy of the method and the intraday and interday precession study presents the applicability of the method for the estimation of resorcinol from any pharmaceutical and cosmetic product containing resorcinol.

The Depth of Cut in Drilling Mode of Rock Cutting

2017 ◽  
Vol 873 ◽  
pp. 292-297
Author(s):  
Yong Sun ◽  
Xing Sheng Li
Keyword(s):  
Quantitative Analysis ◽  
Rock Cutting ◽  
Cutting Process ◽  
Accurate Estimation ◽  
Depth Of Cut ◽  
Drilling Process ◽  
The Difference ◽  
Cutting Modes

Drilling and lateral cutting are two cutting modes used by roadheaders in rock cutting. Accurate estimation of the depth of cut (DOC) of the cutterhead of a roadheader is critical for improving the performance and reliabilityofthe roadheader. Some models have been developed for calculating the DOC of a cutterhead in lateral cutting mode. However, an effective method for computing the DOC of a cutterhead in drilling mode is yet to be developed. As thecharacteristicsof the drilling process are significantly different from those of the lateral cutting process, the models developed for calculating the DOC in lateral cutting mode are not suitable for estimating the DOC ofacutterhead indrilling mode. In this study, a quantitative analysis of the DOC in drilling mode is developed via an investigation ofrock breakout patterns. The results show that in anydrilling case, the DOC of the picks on the cylindrical and conical parts of a cutterhead cannot be calculated by using the advance distance per revolution of the cutterhead. The DOC of a pick is affected by the difference between the cutting radii of the pick and its adjacent picks. It is also affected by the interaction between cutting lines. While the distance between two cutting lines in lateral cutting mode is fixed, the distance betweentwo cutting lines inthe drilling mode can vary. The outcome of the studycan help optimisation of cutterhead design and operation.

Endocrine disruptors in the environment (IUPAC Technical Report)

2003 ◽  
Vol 75 (5) ◽  
pp. 631-681 ◽  
Author(s):  
J. Lintelmann ◽  
A. Katayama ◽  
N. Kurihara ◽  
L. Shore ◽  
A. Wenzel
Keyword(s):  
Endocrine Disruptors ◽  
Hormone Receptors ◽  
Water Solubility ◽  
Endocrine System ◽  
Research Field ◽  
General Idea ◽  
Chemical Substances ◽  
Research Activities ◽  
The Media ◽  
Physicochemical Data

Many chemical substances of natural or anthropogenic origin are suspected or known to be endocrine disruptors, which can influence the endocrine system of life. This observation has led to increased interest on the part of the public and the media, as well as to a steep rise of research activities in the scientific community. New papers and results are presented so fast that it is impossible to give a complete review of this emerging research field. Therefore, this paper tries to give insight into some topics of the great scope of endocrine disruptors in the environment. To get a general idea of the biochemical and biological background, some parts of the endocrine systems of mammalians and nonmammalians are explained. The sections that follow describe important mechanisms of endocrine disruption such as interactions with hormone receptors. Test strategies for anthropogenic chemicals on various organisms are critically reviewed with respect to their problems and gaps concerning endocrine disruptors. The main emphasis of the paper is on the chemical substances suspected or known to be endocrine disruptors. To get a better comprehension of their behavior in the environment, physicochemical data such as water solubility or Kow, as well as information about their use and/or function are reviewed and compared. The main routes of exposure for most chemicals are shortly described, and data about concentrations in the environment (soil/sediment, water) are detailed.

scholarly journals Quantitative 166Ho-microspheres SPECT derived from a dual-isotope acquisition with 99mTc-colloid is clinically feasible

2020 ◽  
Author(s):  
Martina Stella ◽  
Arthur J.A.T. Braat ◽  
Marnix G.E.H. Lam ◽  
Hugo W.A.M. de Jong ◽  
Rob van Rooij
Keyword(s):  
Quantitative Analysis ◽  
Image Quality ◽  
Scatter Correction ◽  
Absorbed Dose ◽  
Observer Agreement ◽  
Qualitative Assessment ◽  
Accurate Estimation ◽  
P Value ◽  
Dual Isotope ◽  
Healthy Liver

Abstract Background Accurate dosimetry is essential in radioembolization. To this purpose, an automatic protocol for healthy liver dosimetry based on dual isotope (DI) SPECT imaging, combining holmium-166 ( 166 Ho)-microspheres and technetium-99m ( 99m Tc)-colloid, was developed: 166 Ho-microspheres used as scout and therapeutic particles and 99m Tc-colloid to identify the healthy liver. DI SPECT allows for an automatic and accurate estimation of absorbed doses, introducing true personalized dosimetry. However, photon crosstalk between isotopes can compromise image quality. This study investigates the effect of 99m Tc downscatter on 166 Ho dosimetry, by comparing 166 Ho-SPECT reconstructions of patient scans acquired before ( 166 Ho-only) and after additional administration of 99m Tc-colloid ( 166 Ho-DI). Results The 166 Ho-only and 166 Ho-DI scans were performed in short succession by injecting 99m Tc-colloid on the scanner table. To compensate for 99m Tc downscatter, its influence was accounted for in the DI image reconstruction using energy window-based scatter correction methods. The qualitative assessment was performed by independent blinded comparison by two nuclear medicine physicians assessing 65 pairs of SPECT/CT. Inter-observer agreement was tested by Cohen's kappa coefficient. For the quantitative analysis, two volumes of interest within the liver, VOI TUMOR and VOI HEALTHY , were manually delineated on the 166 Ho-only reconstruction and transferred to the co-registered 166 Ho-DI reconstruction. Absorbed dose within the resulting VOIs, and in the lungs (VOI LUNGS ), was calculated based on the administered therapeutic activity. The qualitative assessment showed no distinct clinical preference for either 166 Ho-only or 166 Ho-DI SPECT (kappa=0.093). Quantitative analysis indicated that the mean absorbed dose difference between 166 Ho-DI and 1 66 Ho-only was -2.00±2.84 Gy (median 27 Gy; p-value <0.00001), -5.27±8.99 Gy (median 116 Gy; p-value =0.00035) and 0.80±1.08 Gy (median 3 Gy; p-value <0.00001) for VOI HEALTHY , VOI TUMOR and VOI LUNGS respectively. The corresponding Pearson’s correlation coefficient between 166 Ho-only and 166 Ho-DI for absorbed dose was 0.97, 0.99 and 0.82, respectively. Conclusions The DI protocol enables automatic dosimetry with undiminished image quality and accuracy.

scholarly journals Relationship between pore throat and permeability of porous carbonate reservoir in the Middle East

2021 ◽  
Vol 15 (1) ◽  
Author(s):  
Lv Miaomiao ◽  
Song Benbiao ◽  
Tian Changbing ◽  
Mao Xianyu
Keyword(s):  
Quantitative Analysis ◽  
Carbonate Rocks ◽  
Carbonate Reservoir ◽  
Accurate Estimation ◽  
Poor Correlation ◽  
Pore Throat ◽  
Throat Radius ◽  
Pore Networks ◽  
Porosity And Permeability ◽  
Pore Types

AbstractA significant behavior of carbonate reservoirs is poor correlation between porosity and permeability. With the same porosity, the permeability can vary by three orders of magnitude or more. An accurate estimation of permeability for carbonate reservoir has been a challenge for many years. The aim of this study was to establish relationships between pore throat, porosity, and permeability. This study indicates that pore throat radius corresponding to a mercury saturation of 20% (R20) is the best permeability predictor for carbonates with complex porous pore networks. Quantitative analysis was made to achieve three different patterns of pore throat for 417 carbonate samples which cover all pore types of carbonate rocks. Different relationships between porosity, pore throat radius, and permeability have been identified in different patterns, which are utilized to predict more accurate permeability by different pore throat patterns.

An Efficient Statistic for Determining the Diameter of Thin Sectioned Uniform Spheres from Measurements of Biological Samples

1974 ◽  
Vol 32 ◽  
pp. 114-115
Author(s):  
W. R. Schucany ◽  
G. H. Kelsoe ◽  
V. F. Allison
Keyword(s):  
Biological Samples ◽  
Traditional Method ◽  
Cell Types ◽  
Accurate Estimation ◽  
Morphological Identification ◽  
Sectioned Material ◽  
Maximal Diameter ◽  
Similar Cell

Accurate estimation of the size of spheroid organelles from thin sectioned material is often necessary, as uniquely homogenous populations of organelles such as vessicles, granules, or nuclei often are critically important in the morphological identification of similar cell types. However, the difficulty in obtaining accurate diameter measurements of thin sectioned organelles is well known. This difficulty is due to the extreme tenuity of the sectioned material as compared to the size of the intact organelle. In populations where low variance is suspected the traditional method of diameter estimation has been to measure literally hundreds of profiles and to describe the “largest” as representative of the “approximate maximal diameter”.

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