Study of the colloidal stability and optical properties of sunscreen creams

Sunscreen formulations containing inorganic/organic filters or mixture of them were synthesized by oil/water dispersion. The viscosity measurements show that sunscreen formulations are time-dependent non-newtonian fluids. In the CIELab color diagram, the white and/or beige colors presented by formulations do not compromise the aesthetics of the cosmetic product. UV-VIS absorption spectra show that sunscreen creams have high UV shielding ability, mainly the formulations containing inorganic and organic filters mixtures, which provide in vitro SPF and critical wavelength values recommended for UV protection.

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Time dependent DFT investigation of the optical properties of artificial light harvesting special pairs

Physical Chemistry Chemical Physics ◽

10.1039/c6cp00300a ◽

2016 ◽

Vol 18 (22) ◽

pp. 15337-15351 ◽

Cited By ~ 5

Author(s):

Neha Agnihotri ◽

Ronald P. Steer

Keyword(s):

Optical Properties ◽

Absorption Spectra ◽

Light Harvesting ◽

Time Dependent ◽

Artificial Light

Simulated absorption spectra of (ZnTriPP)2DPB dimer in which Q band is enhanced 50 times for visibility.

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Plasminogen Depletion during Streptokinase Treatment or Two-Chain Urokinase Incubation Correlates with Decreased Clot Lysability Ex Vivo and In Vitro

Thrombosis and Haemostasis ◽

10.1055/s-0038-1649714 ◽

1993 ◽

Vol 70 (06) ◽

pp. 0998-1004 ◽

Cited By ~ 13

Author(s):

Páll T Önundarson ◽

H Magnús Haraldsson ◽

Lena Bergmann ◽

Charles W Francis ◽

Victor J Marder

Keyword(s):

Myocardial Infarction ◽

Ex Vivo ◽

Time Dependent ◽

State Variables ◽

Thrombolytic Treatment ◽

Direct Proportion ◽

Plasmin Activity ◽

Plasma Exposure ◽

The Relationship

SummaryThe relationship between lytic state variables and ex vivo clot lysability was investigated in blood drawn from patients during streptokinase administration for acute myocardial infarction. A lytic state was already evident after 5 min of treatment and after 20 min the plasminogen concentration had decreased to 24%, antiplasmin to 7% and fibrinogen 0.2 g/1. Lysis of radiolabeled retracted clots in the patient plasmas decreased from 37 ± 8% after 5 min to 21 ± 8% at 10 min and was significantly lower (8 ± 9%, p <0.005) in samples drawn at 20, 40 and 80 min. Clot lysability correlated positively with the plasminogen concentration (r = 0.78, p = 0.003), but not with plasmin activity. Suspension of radiolabeled clots in normal plasma pre-exposed to 250 U/ml two-chain urokinase for varying time to induce an in vitro lytic state was also associated with decreasing clot lysability in direct proportion with the duration of prior plasma exposure to urokinase. The decreased lysability correlated with the time-dependent reduction in plasminogen concentration (r = 0.88, p <0.0005). Thus, clot lysability decreases in conjunction with the development of the lytic state and the associated plasminogen depletion. The lytic state may therefore limit reperfusion during thrombolytic treatment.

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Plasma Contact Activation and Decrease of Factor V Activity on Negatively-Charged Polyelectrolytes

Thrombosis and Haemostasis ◽

10.1055/s-0038-1661020 ◽

1984 ◽

Vol 51 (01) ◽

pp. 061-064 ◽

Cited By ~ 2

Author(s):

M C Boffa ◽

B Dreyer ◽

C Pusineri

Keyword(s):

Time Dependent ◽

Initial Contact ◽

Factor Xii ◽

Factor V ◽

Contact Activation ◽

Polyelectrolyte Complexes ◽

Plasma Factor ◽

Fresh Plasma ◽

Direct Adsorption

SummaryThe effect of negatively-charged polymers, used in some artificial devices, on plasma clotting and kinin systems was studied in vitro using polyelectrolyte complexes.Contact activation was observed as an immediate, transient and surface-dependent phenomenon. After incubation of the plasma with the polymer a small decrease of factor XII activity was noticed, which corresponded to a greater reduction of prekallikrein activity and to a marked kinin release. No significant decrease of factor XII, prekallikrein, HMW kininogen could be detected immunologically. Only the initial contact of the plasma with the polyelectrolyte lead to activation, subsequently the surface became inert.Beside contact activation, factor V activity also decreased in the plasma. The decrease was surface and time-dependent. It was independent of contact factor activation, and appeared to be related to the sulfonated groups of the polymer. If purified factor V was used instead of plasma factor V, inactivation was immediate and not time-dependent suggesting a direct adsorption on the surface. A second incubation of the plasma-contacted polymer with fresh plasma resulted in a further loss of Factor V activity.

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Synthesis and Evaluation of the Antitumor Activity of Novel 1-(4-Substituted phenyl)-2-ethyl Imidazole Apoptosis Inducers In Vitro

Molecules ◽

10.3390/molecules25184293 ◽

2020 ◽

Vol 25 (18) ◽

pp. 4293

Author(s):

Zhen-Wang Li ◽

Chun-Yan Zhong ◽

Xiao-Ran Wang ◽

Shi-Nian Li ◽

Chun-Yuan Pan ◽

...

Keyword(s):

Antitumor Activity ◽

Tumor Cells ◽

Antiproliferative Activity ◽

Antitumor Agent ◽

Positive Control ◽

Selectivity Index ◽

Time Dependent ◽

Potential Candidate ◽

Dependent Manner

Novel imidazole derivatives were designed, prepared, and evaluated in vitro for antitumor activity. The majority of the tested derivatives showed improved antiproliferative activity compared to the positive control drugs 5-FU and MTX. Among them, compound 4f exhibited outstanding antiproliferative activity against three cancer cell lines and was considerably more potent than both 5-FU and MTX. In particular, the selectivity index indicated that the tolerance of normal L-02 cells to 4f was 23–46-fold higher than that of tumor cells. This selectivity was significantly higher than that exhibited by the positive control drugs. Furthermore, compound 4f induced cell apoptosis by increasing the protein expression levels of Bax and decreasing those of Bcl-2 in a time-dependent manner. Therefore, 4f could be a potential candidate for the development of a novel antitumor agent.

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Effects of Substituents on Photophysical and CO-Photoreleasing Properties of 2,6-Substituted meso-Carboxy BODIPY Derivatives

Chemistry ◽

10.3390/chemistry3010018 ◽

2021 ◽

Vol 3 (1) ◽

pp. 238-255

Author(s):

Esther M. Sánchez-Carnerero ◽

Marina Russo ◽

Andreas Jakob ◽

Lucie Muchová ◽

Libor Vítek ◽

...

Keyword(s):

Carbon Monoxide ◽

Absorption Spectra ◽

Wavelength Range ◽

Toxic Effects ◽

Biological Research ◽

In Vitro Experiments ◽

Vast Array ◽

Physiological Processes ◽

Photochemical Properties

Carbon monoxide (CO) is an endogenously produced signaling molecule involved in the control of a vast array of physiological processes. One of the strategies to administer therapeutic amounts of CO is the precise spatial and temporal control over its release from photoactivatable CO-releasing molecules (photoCORMs). Here we present the synthesis and photophysical and photochemical properties of a small library of meso-carboxy BODIPY derivatives bearing different substituents at positions 2 and 6. We show that the nature of substituents has a major impact on both their photophysics and the efficiency of CO photorelease. CO was found to be efficiently released from π-extended 2,6-arylethynyl BODIPY derivatives possessing absorption spectra shifted to a more biologically desirable wavelength range. Selected photoCORMs were subjected to in vitro experiments that did not reveal any serious toxic effects, suggesting their potential for further biological research.

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Influences of advanced glycosylation end products on the inner blood–retinal barrier in a co-culture cell model in vitro

Open Life Sciences ◽

10.1515/biol-2020-0067 ◽

2020 ◽

Vol 15 (1) ◽

pp. 619-628

Author(s):

Chen Yuan ◽

Ya Mo ◽

Jie Yang ◽

Mei Zhang ◽

Xuejun Xie

Keyword(s):

Electrical Resistance ◽

Cell Model ◽

Polyclonal Antibodies ◽

Time Dependent ◽

Dependent Manner ◽

Blood Retinal Barrier ◽

Advanced Glycosylation End Products ◽

End Products ◽

Advanced Glycosylation

AbstractAdvanced glycosylation end products (AGEs) are harmful factors that can damage the inner blood–retinal barrier (iBRB). Rat retinal microvascular endothelial cells (RMECs) were isolated and cultured, and identified by anti-CD31 and von Willebrand factor polyclonal antibodies. Similarly, rat retinal Müller glial cells (RMGCs) were identified by H&E staining and with antibodies of glial fibrillary acidic protein and glutamine synthetase. The transepithelial electrical resistance (TEER) value was measured with a Millicell electrical resistance system to observe the leakage of the barrier. Transwell cell plates for co-culturing RMECs with RMGCs were used to construct an iBRB model, which was then tested with the addition of AGEs at final concentrations of 50 and 100 mg/L for 24, 48, and 72 h. AGEs in the in vitro iBRB model constructed by RMEC and RMGC co-culture led to the imbalance of the vascular endothelial growth factor (VEGF) and pigment epithelial derivative factor (PEDF), and the permeability of the RMEC layer increased because the TEER decreased in a dose- and time-dependent manner. AGEs increased VEGF but lowered PEDF in a dose- and time-dependent manner. The intervention with AGEs led to the change of the transendothelial resistance of the RMEC layer likely caused by the increased ratio of VEGF/PEDF.

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Effect of hydrophobically modified PEO polymers (PEO-dodecyl) on oil/water microemulsion properties: in vitro and in silico investigations

RSC Advances ◽

10.1039/d0ra09804c ◽

2021 ◽

Vol 11 (12) ◽

pp. 7059-7069

Author(s):

M. Khatouri ◽

R. Ahfir ◽

M. Lemaalam ◽

S. El Khaoui ◽

A. Derouiche ◽

...

Keyword(s):

Integral Equations ◽

In Silico ◽

Md Simulations ◽

Hydrophobically Modified ◽

Oil Water

In this work, we study the effect of grafted PEO-dodecyl co-polymers on the decane/water microemulsions properties. For this purpose, we combined the MD simulations, the OZ integral equations resolved using the HNC closure, and SANS experiments.

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Time-lapse Phase-contrast Microphotography of Cell Populations as a Basis for Improvement of In Vitro Toxicity Assessment

Alternatives to Laboratory Animals ◽

10.1177/026119299202000223 ◽

1992 ◽

Vol 20 (2) ◽

pp. 302-306

Author(s):

Miroslav Červinka

Keyword(s):

Cell Proliferation ◽

Cell Morphology ◽

Video Recording ◽

Toxicity Testing ◽

Time Lapse ◽

Time Dependent ◽

In Vitro Toxicity ◽

Simple Modification ◽

Pertinent Data

Recent trends in the field of in vitro toxicology have centred around the validation of in vitro methods. The ultimate goal is to obtain pertinent data with the minimum of effort. In our laboratory, we have used toxicological methods based on the evaluation of cell morphology and cell proliferation. A method suitable for this purpose is time-lapse microcinematographic (or video) recording of cellular changes, which we used for many years. For practical in vitro toxicity testing, however, this method is far too complicated. Therefore, we have tried to develop a simple modification for the evaluation of cell morphology and cell proliferation, which would still allow for a basic time-dependent analysis. Comparison of detailed microcinematographic analysis with analysis according to our new proliferation assay is demonstrated with cisplatin as the toxicant. We believe that a time-dependent approach could improve the in vitro assessment of toxicity.

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