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Antoine Labbe - One of the best experts on this subject based on the ideXlab platform.
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photophobia and corneal Crystal Density in nephropathic cystinosis an in vivo confocal microscopy and anterior segment optical coherence tomography study
Investigative Ophthalmology & Visual Science, 2015Co-Authors: Hong Liang, Christophe Baudouin, Rachid Tahiri Joutei Hassani, Francoise Brignolebaudouin, Antoine LabbeAbstract:Purpose To analyze the correlation between photophobia and corneal Crystal Density in nephropathic cystinosis using in vivo confocal microscopy (IVCM) and anterior-segment optical coherence tomography (AS-OCT). Methods Forty eyes of 20 patients with nephropathic cystinosis aged 7 to 37 years were included in this study. Ophthalmologic investigations included clinician-assessed and self-assessed evaluations of photophobia, slit-lamp biomicroscopy analysis, the depth of Crystal deposition (DCD) and the central corneal thickness (CCT) in the central cornea measured with AS-OCT, and IVCM analysis of the Crystal Density score (IVCM-CysS), inflammatory cell Density (IVCM-inf), and nerve damage (IVCM-N). Age, sex, intraleukocyte cystine concentrations (ICC), and the need for renal transplantation were also recorded. Results The average subjective and objective photophobia scores were 2.10 ± 1.28 and 1.70 ± 1.41, respectively. Using AS-OCT, the average percentage of Crystal infiltration (OCT-CysP) and was 49.56 ± 27.31% (range, 11.45%-95.81%). The mean IVCM-CysS was 8.84 ± 4.34, the mean Density of inflammatory cells (IVCM-inf) was 178.28 ± 173.00 cells/mm2, and the mean IVCM-N score was 3.11 ± 2.11. Clinician- and self-assessed estimations of photophobia were correlated (R2 = 0.61). No significant correlation was observed between clinician- and self-assessed photophobia scores and ICC or sex. There were significant correlations between clinician- and self-assessed photophobia scores and age, OCT-CysP, IVCM-CysS, IVCM-inf, and IVCM-N. The IVCM-CysS was also correlated with OCT-CysP (R2 = 0.27), IVCM-inf (R2 = 0.37), and IVCM-N (R2 = 0.56). Conclusions In vivo confocal microscopy and AS-OCT are reliable tools to quantify cystinosis corneal Crystals. In patients with nephropathic cystinosis, the intensity of photophobia is associated with the Density of Crystals, infiltration of inflammatory cells, and nerve damage within the cornea.
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a new gel formulation of topical cysteamine for the treatment of corneal cystine Crystals in cystinosis the cystadrops oct 1 study
Molecular Genetics and Metabolism, 2014Co-Authors: Antoine Labbe, Christophe Baudouin, Georges Deschenes, Chantal Loirat, Marina Charbit, Genevieve Guest, Patrick NiaudetAbstract:Abstract Objective To establish the safety and efficacy of a new gel formulation of cysteamine hydrochloride (CH) eye drops, for the treatment of corneal complications of nephropathic cystinosis. Design Open label dose response clinical trial. Participants Eight patients with infantile nephropathic cystinosis including 4 children, 3 adolescents, and 1 adult (mean age at inclusion, 12.1±4.6years) treated with CH 0.1% eye drops. Intervention Patients were treated, in both eyes, with the control CH 0.1% eye drop formulation on average 4 times daily for one month and then switched to Cystadrops® at the same dose frequency. Based on clinical ocular findings, the dose regimen was adapted at D30 and D90 in order to decrease the frequency of instillation. After D90, this dose frequency was maintained, except in cases of Crystal Density worsening. Patients had a follow-up visit every 6months during 48months. Main outcome measures Safety assessment consisted of adverse event and serious adverse event monitoring and recording at each visit. For the efficacy study, the primary endpoint was the corneal cystine Crystal Density measured with an in vivo confocal microscopy (IVCM) score. Results All patients completed the study. During the 4-year study period, neither serious adverse events nor significant adverse events related to the study drug were reported. After switching to Cystadrops®, the IVCM total score decreased from baseline to D90 by a mean of 28.6±17.5% (p Conclusion This study provides evidence that Cystadrops® gel is superior to the CH 0.1% formulation in terms of efficacy and has a good safety profile over a long follow-up period.
Mohammad Hossein Keshavarz - One of the best experts on this subject based on the ideXlab platform.
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Structural, thermochemical and detonation performance of derivatives of 1,2,4,5-tetrazine and 1,4 N-oxide 1,2,4,5-tetrazine as new high-performance and nitrogen-rich energetic materials
Journal of the Iranian Chemical Society, 2017Co-Authors: Akbar Gholami Roknabadi, Mohammad Hossein Keshavarz, Karim Esmailpour, Mehdi ZamaniAbstract:In this study, Density functional theory calculations are used to estimate enthalpy of sublimation, enthalpy of formation and Crystal Density of some important derivatives of 1,2,4,5-tetrazine and 1,4 N -oxide 1,2,4,5-tetrazine. These data were used for predicting their detonation properties including heat of detonation, detonation pressure, detonation velocity, detonation temperature, spark sensitivity, deflagration temperature and power of energetic using appropriate methods. The results show that the title compounds exhibit high positive solid-phase enthalpy of formation. It is found that detonation pressure and detonation velocity of these compounds are high because of the large values of Crystal Density and solid-phase enthalpy of formation. Detonation temperature and spark sensitivity of some derivatives are higher than octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine as one of the high-performance explosives.
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Two novel correlations for assessment of Crystal Density of hazardous ionic molecular energetic materials using their molecular structures
Fluid Phase Equilibria, 2015Co-Authors: Mohammad Hossein Keshavarz, Rahmatollah Rahimi, Ali AkbarzadehAbstract:Abstract This paper introduces two novel simple correlations to assess Crystal Density of ionic molecular energetic materials as a new class of hazardous high energy Density materials. The first one is based on only elemental composition, which can be corrected in the second correlation by two correcting functions on the basis of some molecular fragments in order to include intermolecular interactions. For 100 ionic CHNO molecular systems as training set, the root mean square (rms) percent deviations of predictions for these models relative to experiment are 5.4% and 3.2%, respectively. Corresponding average absolute errors for the new correlations are also 0.077 and 0.042 g/cm3, respectively. These models have been validated with further the 48 ionic compounds as test set, where the computed results of two complex quantum mechanical models have been reported, which give good results. Moreover, the second revised correlation provides the lowest rms percent deviation and average absolute error of predictions for the tested ionic compounds relative to experiment, i.e., 2.3% and 0.036 g/cm3, respectively.
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Thermochemical and detonation performance of boron-nitride analogues of organic azides and benzotrifuroxan as novel high energetic nitrogen-rich precursors
Journal of the Iranian Chemical Society, 2014Co-Authors: Mehdi Zamani, Mohammad Hossein KeshavarzAbstract:Structural and thermochemical properties of boron-nitride analogues of organic azides and benzotrifuroxan, as novel high energetic nitrogen-rich precursors, were studied using M06-2X/6-311G(d,p) and B3LYP/6-311G(d,p) Density functional methods. The influence of azido (N3) group was investigated for the stability, molecular volume, molecular surface area, Crystal Density, positive, negative and total average potentials, variances, average deviation and electrostatic balance parameter on the molecular surface. It was found that Crystal Density and enthalpy of sublimation of azidoborazines are distinctly augmented by increasing the numbers of azido substituents. Meanwhile, the stability of these compounds decreases significantly. The B-substituted azidoborazines are more stable than N-substituted ones. Crystal densities of B-substituted di- and triazidoborazines are also larger than N-substituted compounds. Since the condensed-phase enthalpies of formation of azidoborazines are more positive than nitro and nitraminoborazines, these compounds have greater detonation performance. Detonation pressure and velocity of both triazidotrinitroborazines and boron-nitride analogue of benzotrifuroxan are larger than 2,4,6-trinitrotoluene (TNT). Detonation performances of these compounds are also between cyanuric triazide and triazidotrinitrobenzene.
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Improved method for prediction of Density of energetic compounds using their molecular structure
Structural Chemistry, 2014Co-Authors: Mohammad Hossein Keshavarz, Hadi Motamedoshariati, Hossein Soury, Ahmad DashtizadehAbstract:Accurate prediction of detonation pressure and velocity of an energetic compound through computer codes and empirical methods requires reliable value of its Crystal Density. This paper introduces a reliable method to estimate Crystal Density of a wide range of different types of energetic compounds. This method can applied for any energetic compounds containing at least –NO2, –NNO2, –ONO2, and furazan ring. It is based on some specific molecular fragments of energetic compounds. For 172 different energetic compounds, the root mean squares (rms) percent errors of the new correlation and one of the best available new group additivity methods are 2.16 and 11.0, respectively. The present method also provides more reliable predictions for new explosives such as N,N′-bis(1,2,4-triazol-3-yl)-4,4′-diamino-2,2′,3,3′,5,5′,6,6′-octanitroazobenzene and 2,4,6-tris(3′,5′-diamino-2′,4′,6′-trinitrophenylamino)-1,3,5-triazine.
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a new computer code for assessment of energetic materials with Crystal Density condensed phase enthalpy of formation and activation energy of thermolysis
Propellants Explosives Pyrotechnics, 2013Co-Authors: Mohammad Hossein Keshavarz, Hadi Motamedoshariati, Reza Moghayadnia, Majid Ghanbarzadeh, Jamshid AzarniamehrabanAbstract:Crystal Density and enthalpy of formation of the condensed phase of energetic compounds are two important input parameters for the performance prediction in several computer codes for rapid hazard assessment of energetic materials. A novel easy-to-handle user-friendly computer code in Visual Basic is introduced to predict these parameters for various energetic compounds including nitroaliphatics, nitrate esters, nitramines, polynitroarenes, and polynitroheteroarenes. The calculated values can be used as inputs for other thermochemical/hydrodynamic computer codes. This computer code is also able to calculate the activation energies of thermal decomposition of polynitroarenes and nitramines in condensed state. The number of carbon, hydrogen, oxygen, and nitrogen atoms and specification of some molecular fragments are input parameters for this code without using any experimental data. The new algorithms on the base of easy-to-get input parameters are tested for some new energetic compounds, which provide more reliable results as compared to the best available methods.
Hong Liang - One of the best experts on this subject based on the ideXlab platform.
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a new viscous cysteamine eye drops treatment for ophthalmic cystinosis an open label randomized comparative phase iii pivotal study
Investigative Ophthalmology & Visual Science, 2017Co-Authors: Hong Liang, A Labbe, Jeannie Le Mouhaer, Celine Plisson, Christophe BaudouinAbstract:Purpose The purpose of this study was to evaluate the efficacy of new viscous cysteamine hydrochloride (CH) eye drops (vCH 0.55%) compared with standard CH 0.10% drops treatment. Methods This was an open-label, phase III, randomized, two-arm multicenter trial conducted at two centers in France. Cystinosis patients ≥2 years old were randomized 1:1 to receive eye drops, four times per day for 90 days in both eyes. We compared the superiority in reducing corneal cystine Crystal Density as assessed by in vivo confocal microscopy (IVCM). We also evaluated photophobia, corneal cystine Crystal scores (CCCSs), and cystine Crystal depth measured by optical coherence tomography. Safety objectives were to assess adverse events (AEs), local adverse drug reactions, and ocular safety parameters. Results We included 15 patients with vCH 0.55% and 16 patients with CH 0.10% drops for 90 days. The mean absolute change in IVCM total score at day 90 in the vCH 0.55% drops group (-4.6 ± 3.1) was significantly greater than and superior to the mean absolute change in the CH 0.10% drops group (-0.46 ± 3.38; P < 0.0001). Photophobia, CCCS, and corneal cystine Crystal depth were significantly more improved in the vCH 0.55% drops group than in the CH 0.10% group. The most frequent local adverse drug reactions in both groups were stinging, burning, redness, and blurred vision. Conclusions vCH 0.55% was effective in reducing corneal cystine Crystal Density and superior to treatment with CH 0.10% drops, which offer advantages over hospital pharmacy formulations and is a more preferable and convenient treatment option.
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photophobia and corneal Crystal Density in nephropathic cystinosis an in vivo confocal microscopy and anterior segment optical coherence tomography study
Investigative Ophthalmology & Visual Science, 2015Co-Authors: Hong Liang, Christophe Baudouin, Rachid Tahiri Joutei Hassani, Francoise Brignolebaudouin, Antoine LabbeAbstract:Purpose To analyze the correlation between photophobia and corneal Crystal Density in nephropathic cystinosis using in vivo confocal microscopy (IVCM) and anterior-segment optical coherence tomography (AS-OCT). Methods Forty eyes of 20 patients with nephropathic cystinosis aged 7 to 37 years were included in this study. Ophthalmologic investigations included clinician-assessed and self-assessed evaluations of photophobia, slit-lamp biomicroscopy analysis, the depth of Crystal deposition (DCD) and the central corneal thickness (CCT) in the central cornea measured with AS-OCT, and IVCM analysis of the Crystal Density score (IVCM-CysS), inflammatory cell Density (IVCM-inf), and nerve damage (IVCM-N). Age, sex, intraleukocyte cystine concentrations (ICC), and the need for renal transplantation were also recorded. Results The average subjective and objective photophobia scores were 2.10 ± 1.28 and 1.70 ± 1.41, respectively. Using AS-OCT, the average percentage of Crystal infiltration (OCT-CysP) and was 49.56 ± 27.31% (range, 11.45%-95.81%). The mean IVCM-CysS was 8.84 ± 4.34, the mean Density of inflammatory cells (IVCM-inf) was 178.28 ± 173.00 cells/mm2, and the mean IVCM-N score was 3.11 ± 2.11. Clinician- and self-assessed estimations of photophobia were correlated (R2 = 0.61). No significant correlation was observed between clinician- and self-assessed photophobia scores and ICC or sex. There were significant correlations between clinician- and self-assessed photophobia scores and age, OCT-CysP, IVCM-CysS, IVCM-inf, and IVCM-N. The IVCM-CysS was also correlated with OCT-CysP (R2 = 0.27), IVCM-inf (R2 = 0.37), and IVCM-N (R2 = 0.56). Conclusions In vivo confocal microscopy and AS-OCT are reliable tools to quantify cystinosis corneal Crystals. In patients with nephropathic cystinosis, the intensity of photophobia is associated with the Density of Crystals, infiltration of inflammatory cells, and nerve damage within the cornea.
Christophe Baudouin - One of the best experts on this subject based on the ideXlab platform.
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a new viscous cysteamine eye drops treatment for ophthalmic cystinosis an open label randomized comparative phase iii pivotal study
Investigative Ophthalmology & Visual Science, 2017Co-Authors: Hong Liang, A Labbe, Jeannie Le Mouhaer, Celine Plisson, Christophe BaudouinAbstract:Purpose The purpose of this study was to evaluate the efficacy of new viscous cysteamine hydrochloride (CH) eye drops (vCH 0.55%) compared with standard CH 0.10% drops treatment. Methods This was an open-label, phase III, randomized, two-arm multicenter trial conducted at two centers in France. Cystinosis patients ≥2 years old were randomized 1:1 to receive eye drops, four times per day for 90 days in both eyes. We compared the superiority in reducing corneal cystine Crystal Density as assessed by in vivo confocal microscopy (IVCM). We also evaluated photophobia, corneal cystine Crystal scores (CCCSs), and cystine Crystal depth measured by optical coherence tomography. Safety objectives were to assess adverse events (AEs), local adverse drug reactions, and ocular safety parameters. Results We included 15 patients with vCH 0.55% and 16 patients with CH 0.10% drops for 90 days. The mean absolute change in IVCM total score at day 90 in the vCH 0.55% drops group (-4.6 ± 3.1) was significantly greater than and superior to the mean absolute change in the CH 0.10% drops group (-0.46 ± 3.38; P < 0.0001). Photophobia, CCCS, and corneal cystine Crystal depth were significantly more improved in the vCH 0.55% drops group than in the CH 0.10% group. The most frequent local adverse drug reactions in both groups were stinging, burning, redness, and blurred vision. Conclusions vCH 0.55% was effective in reducing corneal cystine Crystal Density and superior to treatment with CH 0.10% drops, which offer advantages over hospital pharmacy formulations and is a more preferable and convenient treatment option.
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photophobia and corneal Crystal Density in nephropathic cystinosis an in vivo confocal microscopy and anterior segment optical coherence tomography study
Investigative Ophthalmology & Visual Science, 2015Co-Authors: Hong Liang, Christophe Baudouin, Rachid Tahiri Joutei Hassani, Francoise Brignolebaudouin, Antoine LabbeAbstract:Purpose To analyze the correlation between photophobia and corneal Crystal Density in nephropathic cystinosis using in vivo confocal microscopy (IVCM) and anterior-segment optical coherence tomography (AS-OCT). Methods Forty eyes of 20 patients with nephropathic cystinosis aged 7 to 37 years were included in this study. Ophthalmologic investigations included clinician-assessed and self-assessed evaluations of photophobia, slit-lamp biomicroscopy analysis, the depth of Crystal deposition (DCD) and the central corneal thickness (CCT) in the central cornea measured with AS-OCT, and IVCM analysis of the Crystal Density score (IVCM-CysS), inflammatory cell Density (IVCM-inf), and nerve damage (IVCM-N). Age, sex, intraleukocyte cystine concentrations (ICC), and the need for renal transplantation were also recorded. Results The average subjective and objective photophobia scores were 2.10 ± 1.28 and 1.70 ± 1.41, respectively. Using AS-OCT, the average percentage of Crystal infiltration (OCT-CysP) and was 49.56 ± 27.31% (range, 11.45%-95.81%). The mean IVCM-CysS was 8.84 ± 4.34, the mean Density of inflammatory cells (IVCM-inf) was 178.28 ± 173.00 cells/mm2, and the mean IVCM-N score was 3.11 ± 2.11. Clinician- and self-assessed estimations of photophobia were correlated (R2 = 0.61). No significant correlation was observed between clinician- and self-assessed photophobia scores and ICC or sex. There were significant correlations between clinician- and self-assessed photophobia scores and age, OCT-CysP, IVCM-CysS, IVCM-inf, and IVCM-N. The IVCM-CysS was also correlated with OCT-CysP (R2 = 0.27), IVCM-inf (R2 = 0.37), and IVCM-N (R2 = 0.56). Conclusions In vivo confocal microscopy and AS-OCT are reliable tools to quantify cystinosis corneal Crystals. In patients with nephropathic cystinosis, the intensity of photophobia is associated with the Density of Crystals, infiltration of inflammatory cells, and nerve damage within the cornea.
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a new gel formulation of topical cysteamine for the treatment of corneal cystine Crystals in cystinosis the cystadrops oct 1 study
Molecular Genetics and Metabolism, 2014Co-Authors: Antoine Labbe, Christophe Baudouin, Georges Deschenes, Chantal Loirat, Marina Charbit, Genevieve Guest, Patrick NiaudetAbstract:Abstract Objective To establish the safety and efficacy of a new gel formulation of cysteamine hydrochloride (CH) eye drops, for the treatment of corneal complications of nephropathic cystinosis. Design Open label dose response clinical trial. Participants Eight patients with infantile nephropathic cystinosis including 4 children, 3 adolescents, and 1 adult (mean age at inclusion, 12.1±4.6years) treated with CH 0.1% eye drops. Intervention Patients were treated, in both eyes, with the control CH 0.1% eye drop formulation on average 4 times daily for one month and then switched to Cystadrops® at the same dose frequency. Based on clinical ocular findings, the dose regimen was adapted at D30 and D90 in order to decrease the frequency of instillation. After D90, this dose frequency was maintained, except in cases of Crystal Density worsening. Patients had a follow-up visit every 6months during 48months. Main outcome measures Safety assessment consisted of adverse event and serious adverse event monitoring and recording at each visit. For the efficacy study, the primary endpoint was the corneal cystine Crystal Density measured with an in vivo confocal microscopy (IVCM) score. Results All patients completed the study. During the 4-year study period, neither serious adverse events nor significant adverse events related to the study drug were reported. After switching to Cystadrops®, the IVCM total score decreased from baseline to D90 by a mean of 28.6±17.5% (p Conclusion This study provides evidence that Cystadrops® gel is superior to the CH 0.1% formulation in terms of efficacy and has a good safety profile over a long follow-up period.
N. Bouhmaida - One of the best experts on this subject based on the ideXlab platform.
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Elusive contribution of the experimental surface molecular electrostatic potential and promolecule approximation in the empirical estimate of the Crystal Density
Journal of Chemical Physics, 2005Co-Authors: N. Bouhmaida, Ghermani N.e.Abstract:The aim of this study is to probe the Crystal Density (Dc) description in terms of pertinent molecular characteristics and properties. In this purpose, the electrostatic potential was derived from available experimental electron Density multipole parameters of molecular compounds with different Dc magnitudes. The surface electrostatic potential has been analyzed through the positive and negative statistical variances. The surface of the molecule is here corresponding to particular isoDensity values according to Bader’s topological theory. Following the successful Politzer’s method based on quantum mechanics calculations to empirically describe macroscopic properties, the Crystal Density was regressed on the molecular Density and the surface electrostatic potential variance. This latter appears to be a poor statistical descriptor of the Crystal Density when the experimentally derived electrostatic potential is used and it does not significantly improve the fit of Dc to molecular Density alone. Compared to Politzer’s approach based on gas phase isolated molecules, the experimental electrostatic potential is biased by the interactions in the Crystal lattice. As an alternative to other sophisticated methods, the promolecule isoDensity surface offers a quite useful and straightforward way to define the molecular volumes. The reported description of the Crystal Density for a set of 50 molecules using the promolecule approach yields satisfactory results.
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elusive contribution of the experimental surface molecular electrostatic potential and promolecule approximation in the empirical estimate of the Crystal Density
Journal of Chemical Physics, 2005Co-Authors: N. Bouhmaida, N E GhermaniAbstract:The aim of this study is to probe the Crystal Density (Dc) description in terms of pertinent molecular characteristics and properties. In this purpose, the electrostatic potential was derived from available experimental electron Density multipole parameters of molecular compounds with different Dc magnitudes. The surface electrostatic potential has been analyzed through the positive and negative statistical variances. The surface of the molecule is here corresponding to particular isoDensity values according to Bader’s topological theory. Following the successful Politzer’s method based on quantum mechanics calculations to empirically describe macroscopic properties, the Crystal Density was regressed on the molecular Density and the surface electrostatic potential variance. This latter appears to be a poor statistical descriptor of the Crystal Density when the experimentally derived electrostatic potential is used and it does not significantly improve the fit of Dc to molecular Density alone. Compared to ...