cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.11997726.v1
title: Towards the cosmetic application of Passiflora coccinea (Aubl.): antioxidant activity and photo protective capacity of the methanolic and glycolic leaf extracts

description: The present study aimed at the evaluation of Passiflora coccinea (Aubl.) antioxidant and photo protective in vitro activities, looking forward to their application as antiaging or sunscreen agents in cosmetic formulations. Methanolic and glycolic leaf extracts were prepared by three methods: ultrasound assisted extraction (UAE, 30 min.), maceration at room temperature (72 h) and maceration at 30 ºC (72 h). The antioxidant activities of the extracts were measured by DPPH and ORAC-FL assays and they were incorporated into a cosmetic emulsion to have their sun protection factor (SPF) measured spectrophotometricaly. The antioxidant activity of the emulsions were measured by DPPH and ORAC as well. C-glycosyl-flavones were identified in the extracts by ESI-MS/MS, in comparision with standards. The UAE methanolic extract and the maceration at 30 ºC glycolic extract were submmited to HPLC-DAD analysis and isovitexin was quantifyed in both by a validated method. The methanolic extract antioxidant activity was independent of the extraction method, higher than reported for other species of Passiflora and detectable when incorporated into the emulsion formulation. Maceration at 30oC was the most suitable method for glycolic extraction and its antioxidant activity was lower than the value presented by the methanolic extracts. None of the extracts exhibited a SPF value. Isovitexin in the UAE methanolic extract was 12.67 times higher than the most active glycolic extract, aside of their similar chromatographic profiles. Although a SPF value was not detected, the results indicate that P. coccinea can be a potential new source of antioxidants for topical antiaging formulations.
DOI: 10.6084/m9.figshare.11997717
title: Characterization of bacterial endophytes from Myanmar medicinal plants for antimicrobial activity against human and plant pathogens

description: This research aimed to investigate the antagonistic activity of the bacterial endophytes from Myanmar medicinal plants. Thirty-one bacterial isolates were isolated from Myanmar medicinal plants: Tinospora cordifolia (Wild.) Miers., Catharanthus roseus G. Don., Tectona hamiltoniana Wall. and Boscia variabilis Collett & Hemsl. (Capparaceae). Dual culture and agar well diffusion methods were used for antimicrobial assay. One endophyte from Catharanthus roseus and two bacterial isolates from Boscia variabilis Collett & Hemsl. (Capparaceae) had not only the antibacterial activity towards the human pathogenic bacteria but also the antifungal activity against the plant pathogenic fungi. From 16S rRNA sequencing, one strain from Catharanthus roseus G. Don. was Bacillus amyloliquefaciens DSM7 and two antagonistic strains from Boscia variabilis Collett & Hemsl. (Capparaceae) were Bacillus subtilis subsp. subtilis str. 168 and Bacillus amyloliquefaciens DSM7, respectively. The best medium for the maximum production of the bioactive compounds was Bacillus medium supplemented with the 4% of starch and 0.3% of peptone for B. amyloliquefaciens DSM7 and B. subtilis subsp. subtilis str. 168 showed the maximum antimicrobial compounds production when it was incubated in the medium amended with 3% of starch and 2% of peptone. The optimum conditions for the the maximum production of the antimicrobial compound were the medium pH of 6 at 35 ºC after two days of incubation for B. amyloliquefaciens DSM 7 and B. subtitlis subsp. subtilis str. 168 secreted the maximum concentration of the bioactive compounds at pH 7.5 and 35˚C on second day incubation period. In conclusion, the isolated endophytic bacteria showed the strong antimicrobial activity towards the pathogenic microbes and they could be used in medicine and agriculture as well.
DOI: 10.6084/m9.figshare.11997717.v1
title: Characterization of bacterial endophytes from Myanmar medicinal plants for antimicrobial activity against human and plant pathogens

description: This research aimed to investigate the antagonistic activity of the bacterial endophytes from Myanmar medicinal plants. Thirty-one bacterial isolates were isolated from Myanmar medicinal plants: Tinospora cordifolia (Wild.) Miers., Catharanthus roseus G. Don., Tectona hamiltoniana Wall. and Boscia variabilis Collett & Hemsl. (Capparaceae). Dual culture and agar well diffusion methods were used for antimicrobial assay. One endophyte from Catharanthus roseus and two bacterial isolates from Boscia variabilis Collett & Hemsl. (Capparaceae) had not only the antibacterial activity towards the human pathogenic bacteria but also the antifungal activity against the plant pathogenic fungi. From 16S rRNA sequencing, one strain from Catharanthus roseus G. Don. was Bacillus amyloliquefaciens DSM7 and two antagonistic strains from Boscia variabilis Collett & Hemsl. (Capparaceae) were Bacillus subtilis subsp. subtilis str. 168 and Bacillus amyloliquefaciens DSM7, respectively. The best medium for the maximum production of the bioactive compounds was Bacillus medium supplemented with the 4% of starch and 0.3% of peptone for B. amyloliquefaciens DSM7 and B. subtilis subsp. subtilis str. 168 showed the maximum antimicrobial compounds production when it was incubated in the medium amended with 3% of starch and 2% of peptone. The optimum conditions for the the maximum production of the antimicrobial compound were the medium pH of 6 at 35 ºC after two days of incubation for B. amyloliquefaciens DSM 7 and B. subtitlis subsp. subtilis str. 168 secreted the maximum concentration of the bioactive compounds at pH 7.5 and 35˚C on second day incubation period. In conclusion, the isolated endophytic bacteria showed the strong antimicrobial activity towards the pathogenic microbes and they could be used in medicine and agriculture as well.
DOI: 10.6084/m9.figshare.11997735
title: Stability-indicating HPLC-DAD method for the simultaneous determination of fluoroquinolone in combination with a non-steroidal anti-inflammatory drug in pharmaceutical formulation

description: We developed and validated a stability-indicating assay method for the simultaneous determination of enrofloxacin and piroxicam in combination and in the presence of degradation products. Reverse-phase high-performance liquid chromatography analyses were carried out on a Vertisep C18 column and acetonitrile-water (48:52 v/v, pH 3.0) mobile phase with a 1.00 mL min−1 flow rate. The efficient chromatographic separation of these drugs and their forced degradation products was achieved in less than 5min with a peak purity match factor higher than 950. The method used showed linearity in the concentration ranges of 0.25 to 16.0 µg mL−1 for enrofloxacin (r = 0.9997) and 0.125 to 8.0 µg mL−1 for piroxicam (r = 0.9999) as well as precision (relative standard deviation lower than 2%), accuracy (mean recovery 100 ± 2%), and robustness, according to ICH (International Conference on Harmonization) and AOAC (Association of Official Analytical Chemists) guidelines. This method can simultaneously determine the combination of these drugs in a veterinary formulation and separate the drug peaks from their forced degradation products. Additionally, its optimized chromatographic conditions can contribute to the quality control of this formulation in pharmaceutical manufacturing plants and minimize waste from the organic solvent.
DOI: 10.6084/m9.figshare.11997735.v1
title: Stability-indicating HPLC-DAD method for the simultaneous determination of fluoroquinolone in combination with a non-steroidal anti-inflammatory drug in pharmaceutical formulation

description: We developed and validated a stability-indicating assay method for the simultaneous determination of enrofloxacin and piroxicam in combination and in the presence of degradation products. Reverse-phase high-performance liquid chromatography analyses were carried out on a Vertisep C18 column and acetonitrile-water (48:52 v/v, pH 3.0) mobile phase with a 1.00 mL min−1 flow rate. The efficient chromatographic separation of these drugs and their forced degradation products was achieved in less than 5min with a peak purity match factor higher than 950. The method used showed linearity in the concentration ranges of 0.25 to 16.0 µg mL−1 for enrofloxacin (r = 0.9997) and 0.125 to 8.0 µg mL−1 for piroxicam (r = 0.9999) as well as precision (relative standard deviation lower than 2%), accuracy (mean recovery 100 ± 2%), and robustness, according to ICH (International Conference on Harmonization) and AOAC (Association of Official Analytical Chemists) guidelines. This method can simultaneously determine the combination of these drugs in a veterinary formulation and separate the drug peaks from their forced degradation products. Additionally, its optimized chromatographic conditions can contribute to the quality control of this formulation in pharmaceutical manufacturing plants and minimize waste from the organic solvent.
DOI: 10.6084/m9.figshare.11997738
title: Development and validation of an HPLC-UV method for accelerated stability study and pharmacokinetic analysis of venlafaxine

description: A reverse phase high performance liquid chromatography method has been developed and validated for accelerated stability study and determination of pharmacokinetic parameters of venlafaxine HCl. The chromatographic separation was carried out using ODS analytical column (250 × 4.6 mm i.d., 5 µm particle size). The mobile phase included acetonitrile, methanol and potassium dihydrogen phosphate buffer (30:30:40; pH 6.1) at a flow rate 1.5 mL min−1. UV-Visible detector was used at wavelength of 227 nm to monitor elutions. Retention time observed was 2.745 min. The method was validated for linearity, accuracy, precision, sensitivity and robustness. Accelerated stability study of venlafaxine HCl capsules was carried out at 40 and 50 ºC under 75% RH level. Suggested method was successfully applied for the pharmacokinetic analysis of venlafaxine hydrochloride tablets. Each of ten albino rabbits (≈ 1.2 kg each) was orally administered with 5 mg dose of venlafaxine HCl. The method was proved to be linear (R2 &gt;0.998), accurate (98.25-99.27%), sensitive (LOD: 35ngmL−1; LOQ: 105 ng mL−1) and robust (RSD&lt;1%). The drug showed stability at accelerated conditions of temperature and humidity. The main pharmacokinetic parameters of tested products were as follows: tmax was 2.5h, Cmax was 56.5 µg mL−1, t1/2 was 8.2 h, AUC0-36 was 845.9 µg h mL−1. The developed method is suitable to apply for quality control analysis and pharmacokinetic studies.
DOI: 10.6084/m9.figshare.11997738.v1
title: Development and validation of an HPLC-UV method for accelerated stability study and pharmacokinetic analysis of venlafaxine

description: A reverse phase high performance liquid chromatography method has been developed and validated for accelerated stability study and determination of pharmacokinetic parameters of venlafaxine HCl. The chromatographic separation was carried out using ODS analytical column (250 × 4.6 mm i.d., 5 µm particle size). The mobile phase included acetonitrile, methanol and potassium dihydrogen phosphate buffer (30:30:40; pH 6.1) at a flow rate 1.5 mL min−1. UV-Visible detector was used at wavelength of 227 nm to monitor elutions. Retention time observed was 2.745 min. The method was validated for linearity, accuracy, precision, sensitivity and robustness. Accelerated stability study of venlafaxine HCl capsules was carried out at 40 and 50 ºC under 75% RH level. Suggested method was successfully applied for the pharmacokinetic analysis of venlafaxine hydrochloride tablets. Each of ten albino rabbits (≈ 1.2 kg each) was orally administered with 5 mg dose of venlafaxine HCl. The method was proved to be linear (R2 &gt;0.998), accurate (98.25-99.27%), sensitive (LOD: 35ngmL−1; LOQ: 105 ng mL−1) and robust (RSD&lt;1%). The drug showed stability at accelerated conditions of temperature and humidity. The main pharmacokinetic parameters of tested products were as follows: tmax was 2.5h, Cmax was 56.5 µg mL−1, t1/2 was 8.2 h, AUC0-36 was 845.9 µg h mL−1. The developed method is suitable to apply for quality control analysis and pharmacokinetic studies.
DOI: 10.17632/yf7f3w92w6.1
title: A molecular clock controls periodically driven cell migration in confined spaces

description: Navigation through dense, physically confining extracellular matrix is common in invasive cell spread and tissue re-organization, but is still poorly understood. Here, we show that this migration is mediated by cyclic changes in the activity of a small GTP-ase RhoA, dependent on the oscillatory changes in the activity and abundance of the RhoA Guanine Exchange Factor, GEF-H1, triggered by a persistent increase in the intracellular Ca2+ levels. We show that the molecular clock driving these cyclic changes is mediated by two coupled negative feedback loops, dependent on the microtubule dynamics, with the frequency that can be experimentally modulated based on a predictive mathematical model. We further demonstrate that an increasing frequency of the clock translates into a faster cell migration within physically confining spaces. This work lays the foundation for a better understanding of the molecular mechanisms dynamically driving cell migration in complex environments.
DOI: 10.17632/x6dpzh22xs.1
title: Data for "Experimental evidence supporting an overturned iron-titanium-rich melt layer in the deep lunar interior"

description: Data for "Experimental evidence supporting an overturned iron-titanium-rich melt layer in the deep lunar interior"
DOI: 10.6084/m9.figshare.11997729
title: Application of redox reactions for the determination of valganciclovir hydrochloride in pharmaceuticals

description: Two simple, selective and sensitive spectrophotometric methods were developed and validated for the determination of valganciclovir hydrochloride (VLGH) in pure drug and tablets. The first method was based on the reduction of iron(III) to iron(II) by VLGH and subsequent formation of iron(III)-ferricyanide complex (Prussian blue) in acid medium which was measured at 730 nm (method A). In the second method (method B), permanganate was reduced by VLGH to bluish green manganate in alkaline medium and the absorbance was measured at 610 nm. The absorbance measured in each case was related to VLGH concentration. The experimental conditions were carefully studied and optimized. Beer’s law was obeyed over the concentration ranges of 2.5-20.0 and 2.0-40.0 µg mL-1 for method A and method B, respectively, with corresponding molar absorptivity values of 1.28×104 and 6.88×103 L mol-1 cm-1. The limits of detection (LOD) and quantification (LOQ) were 0.11 and 0.33 µg mL-1 (method A) and 0.21 and 0.64 µg mL-1 (method B). Within-day and between-day relative standard deviations (%RSD) at three different concentrations levels were &lt; 2.4%, and the respective relative errors (%RE) were ≤ 3%. The proposed methods were successfully applied to the determination of VLGH in tablets, and the results confirmed that the proposed methods were equally precise and accurate as the official method.
DOI: 10.6084/m9.figshare.11997729.v1
title: Application of redox reactions for the determination of valganciclovir hydrochloride in pharmaceuticals

description: Two simple, selective and sensitive spectrophotometric methods were developed and validated for the determination of valganciclovir hydrochloride (VLGH) in pure drug and tablets. The first method was based on the reduction of iron(III) to iron(II) by VLGH and subsequent formation of iron(III)-ferricyanide complex (Prussian blue) in acid medium which was measured at 730 nm (method A). In the second method (method B), permanganate was reduced by VLGH to bluish green manganate in alkaline medium and the absorbance was measured at 610 nm. The absorbance measured in each case was related to VLGH concentration. The experimental conditions were carefully studied and optimized. Beer’s law was obeyed over the concentration ranges of 2.5-20.0 and 2.0-40.0 µg mL-1 for method A and method B, respectively, with corresponding molar absorptivity values of 1.28×104 and 6.88×103 L mol-1 cm-1. The limits of detection (LOD) and quantification (LOQ) were 0.11 and 0.33 µg mL-1 (method A) and 0.21 and 0.64 µg mL-1 (method B). Within-day and between-day relative standard deviations (%RSD) at three different concentrations levels were &lt; 2.4%, and the respective relative errors (%RE) were ≤ 3%. The proposed methods were successfully applied to the determination of VLGH in tablets, and the results confirmed that the proposed methods were equally precise and accurate as the official method.
DOI: 10.6084/m9.figshare.11997732
title: Comparative analyses of response surface methodology and artificial neural networks on incorporating tetracaine into liposomes

description: This study evaluated the incorporation of tetracaine into liposomes by RSM (Response Surface Methodology) and ANN (Artificial Neural Networks) based models. RCCD (rotational central composite design) and ANN were performed to optimize the sonication conditions of particles containing 100 % lipid. Laser light scattering was used to perform measure hydrodynamic radius and size distribution of vesicles. The liposomal formulations were analyzed by incorporating the drug into the hydrophilic phase or the lipophilic phase. RCCD and ANN were conducted, having the lipid/cholesterol ratio and concentration of tetracaine as variables investigated and, the encapsulation efficiency and mean diameter of the vesicles as response variables. The optimum sonication condition set at a power of 16 kHz and 3 minutes, resulting in sizes smaller than 800 nm. Maximum encapsulation efficiency (39.7 %) was obtained in the hydrophilic phase to a tetracaine concentration of 8.37 mg/mL and 79.5:20.5% lipid/cholesterol ratio. Liposomes were stable for about 30 days (at 4 ºC), and the drug encapsulation efficiency was higher in the hydrophilic phase. The experimental results of RCCD-RSM and ANN techniques show ANN obtained more refined prediction errors that RCCD-RSM technique, therefore, ANN can be considered as an efficient mathematical method to characterize the incorporation of tetracaine into liposomes.
DOI: 10.6084/m9.figshare.11997732.v1
title: Comparative analyses of response surface methodology and artificial neural networks on incorporating tetracaine into liposomes

description: This study evaluated the incorporation of tetracaine into liposomes by RSM (Response Surface Methodology) and ANN (Artificial Neural Networks) based models. RCCD (rotational central composite design) and ANN were performed to optimize the sonication conditions of particles containing 100 % lipid. Laser light scattering was used to perform measure hydrodynamic radius and size distribution of vesicles. The liposomal formulations were analyzed by incorporating the drug into the hydrophilic phase or the lipophilic phase. RCCD and ANN were conducted, having the lipid/cholesterol ratio and concentration of tetracaine as variables investigated and, the encapsulation efficiency and mean diameter of the vesicles as response variables. The optimum sonication condition set at a power of 16 kHz and 3 minutes, resulting in sizes smaller than 800 nm. Maximum encapsulation efficiency (39.7 %) was obtained in the hydrophilic phase to a tetracaine concentration of 8.37 mg/mL and 79.5:20.5% lipid/cholesterol ratio. Liposomes were stable for about 30 days (at 4 ºC), and the drug encapsulation efficiency was higher in the hydrophilic phase. The experimental results of RCCD-RSM and ANN techniques show ANN obtained more refined prediction errors that RCCD-RSM technique, therefore, ANN can be considered as an efficient mathematical method to characterize the incorporation of tetracaine into liposomes.
DOI: 10.18112/openneuro.ds003465.v1.0.6
title: DMCC55B
DOI: 10.6084/m9.figshare.11997312
title: Nonsteroidal anti-inflammatory drugs as potential ecto-nucleotide phosphodiesterase inhibitors

description: Phosphodiesterases (PDE) are group of enzymes which catalyze the hydrolysis of cAMP and cGMP. Since these cyclic phosphate moieties worked as intracellular second messengers in numerous physiological processes, their inhibition can affect normal physiology of living system. NSAIDs are among the frequently prescribed medications, because of their efficacy as analgesic, antipyretic and anti-inflammatory agents. They are known to block cyclooxygenase pathway. In limited data NSAIDs has been shown anti-tumor potential, and phosphodiesterase inhibition has assumed to be one of the mechanism. To date no further evaluation being done. Further, NSAIDs are classified as cyclooxygenase inhibitors and phosphodiesterase inhibition can imprint its side effects. This study first time investigates the effects of NSAIDs on phosphodiesterase 1 inhibition. The activity against snake venom phosphodiesterase 1 was assayed on a microtitre plate reader spectrophotometer. Selective COX-2 inhibitor, celecoxib, exhibited a potent PDE1 inhibitory activity, at therapeutic doses, with an IC50 value of 29.4 µM. The findings of our study are indicative of new pharmacological actions of cyclooxygenase inhibitors. This article presents the PDE inhibitory properties as a new effects of already existing drugs. These additional effects could be potentially helpful for researchers to assess other physiological and pathological states.
DOI: 10.6084/m9.figshare.11997312.v1
title: Nonsteroidal anti-inflammatory drugs as potential ecto-nucleotide phosphodiesterase inhibitors

description: Phosphodiesterases (PDE) are group of enzymes which catalyze the hydrolysis of cAMP and cGMP. Since these cyclic phosphate moieties worked as intracellular second messengers in numerous physiological processes, their inhibition can affect normal physiology of living system. NSAIDs are among the frequently prescribed medications, because of their efficacy as analgesic, antipyretic and anti-inflammatory agents. They are known to block cyclooxygenase pathway. In limited data NSAIDs has been shown anti-tumor potential, and phosphodiesterase inhibition has assumed to be one of the mechanism. To date no further evaluation being done. Further, NSAIDs are classified as cyclooxygenase inhibitors and phosphodiesterase inhibition can imprint its side effects. This study first time investigates the effects of NSAIDs on phosphodiesterase 1 inhibition. The activity against snake venom phosphodiesterase 1 was assayed on a microtitre plate reader spectrophotometer. Selective COX-2 inhibitor, celecoxib, exhibited a potent PDE1 inhibitory activity, at therapeutic doses, with an IC50 value of 29.4 µM. The findings of our study are indicative of new pharmacological actions of cyclooxygenase inhibitors. This article presents the PDE inhibitory properties as a new effects of already existing drugs. These additional effects could be potentially helpful for researchers to assess other physiological and pathological states.
DOI: 10.6084/m9.figshare.11997318
title: Chiral discrimination of amlodipine from pharmaceutical products using capillary electrophoresis

description: The present work describes the development of a capillary electrophoresis (CE) method for the chiral discrimination of amlodipine (AML) enantiomers using cyclodextrine (CD) derivatives as chiral selectors. A large number of native and derivatized, neutral and ionized CD derivatives were screened to find the optimal chiral selector; and carboximethyl-β-CD (CM-β-CD) was selected for the enantiomeric discrimination. A factorial analysis study was performed by orthogonal experimental design in which several factors were varied at the same time to optimize the separation method. The optimized method (25 mM phosphate buffer, pH = 9.0, 15 mM CM-β-CD, 15 ºC, + 25 kV, 30 mbar/1 second, detection wavelength 230 nm) was successfully applied for the baseline separation of AML enantiomers within 5 minutes. Successful validation and application of the proposed CE method suggest its routine use in enantioselective control of AML in pharmaceutical preparations.