Conservação de peças anatômicas em cloreto de sódio: um estudo com produto de fecundação / Conservation of anatomical parts in sodium chloride: a study with fertilization product / Conservación de partes anatómicas en cloruro sódico: un estudio con producto de fertilización

Introdução: Os materiais de origem humana geralmente são conservados em formaldeído, para possibilitar o estudo da anatomia humana, tal conservante possui baixo custo e boa fixação, contudo é toxico. Diante do exposto é necessário, o estudo de outros métodos de conservação, menos prejudiciais, como a solução de NaCl 30%. Objetivo: Comparar a conservação de peças anatômicas em solução de NaCl à 30% e formaldeído a 10%. Método: Pesquisa experimental, exploratória e descritiva, realizada com dois produtos de abortamento, no laboratório de anatomia de uma universidade pública, no estado do Paraná/BR. Foi realizada fixação em solução de formol 10%, em seguida uma amostra foi lavado em água corrente e armazenado em solução de NaCl à 30%. Após 6 meses da conservação em solução salina, foram coletadas amostras, estas foram submetidas a análise de crescimento bacteriano. Avaliou-se tonalidade e turgor cutâneo, odor e peso, bem como crescimento bacteriano. O estudo seguiu os preceitos éticos (CAAE: 53740121.9.0000.9247). Resultados: Foram realizadas observações após 24h, 7, 30, 60, 90 e 180 dias. O feto em solução de NaCl não possui odor, e diminuição do turgor da pele. Ambas a amostras não apresentaram crescimento bacteriano. Considerações finais: A solução de NaCl a 30% desidrata a pele, mas não altera significativamente a forma e estrutura, ainda não possui odor e nem toxicidade, o que garante benefícios a saúde de quem os manipula, bem como tal concentração de NaCl inibe de forma efetiva o crescimento bacteriano nos tecidos e na própria solução, se demostrando eficaz na conservação.

Introduction: The materials of human origin are usually preserved in formaldehyde, to enable the study of human anatomy, this preservative has low cost and good fixation, however it is toxic. Therefore, it is necessary to study other less harmful preservation methods, such as 30% NaCl solution. Objective: To compare the preservation of anatomical specimens in 30% NaCl solution and 10% formaldehyde solution. Method: Experimental, exploratory and descriptive research, carried out with two abortion products, in the anatomy laboratory of a public university, in the state of Paraná/BR. Fixation in 10% formaldehyde solution was performed, after which a sample was washed in running water and stored in a 30% NaCl solution. After 6 months of preservation in saline solution, samples were collected and submitted to bacterial growth analysis. Skin tone and turgor, odor, weight, and bacterial growth were evaluated. The study followed the ethical precepts (CAAE: 53740121.9.0000.9247). Results: Observations were made after 24h, 7, 30, 60, 90 and 180 days. The fetus in NaCl solution had no odor, and decreased skin turgor. Both samples showed no bacterial growth. Final considerations: The 30% NaCl solution dehydrates the skin, but does not alter significantly the shape and structure, and also has no odor or toxicity, which guarantees health benefits to those who handle them, and such concentration of NaCl inhibits effectively the bacterial growth in the tissues and in the solution itself, proving to be effective in conservation.

Introducción: Los materiales de origen humano suelen conservarse en formol, para posibilitar el estudio de la anatomía humana, este conservante tiene bajo coste y buena fijación, sin embargo es tóxico. Por ello, es necesario estudiar otros métodos de conservación menos nocivos, como la solución de NaCl al 30%. Objetivo: Comparar la conservación de especímenes anatómicos en solución de NaCl al 30% y en solución de formaldehído al 10%. Método: Investigación experimental, exploratoria y descriptiva, realizada con dos abortos, en el laboratorio de anatomía de una universidad pública, en el estado de Paraná/BR. Fue realizada fijación en solución de formaldehído al 10%, después de lo cual la muestra fue lavada en agua corriente y almacenada en solución de NaCl al 30%. Tras 6 meses de conservación en solución salina, se recogieron las muestras y se sometieron a análisis de crecimiento bacteriano. Se evaluaron el tono y la turgencia de la piel, el olor, el peso y el crecimiento bacteriano. El estudio siguió los preceptos éticos (CAAE: 53740121.9.0000.9247). Resultados: Las observaciones se realizaron después de 24h, 7, 30, 60, 90 y 180 días. El feto en solución de NaCl no tenía olor, y la turgencia de la piel disminuyó. Ambas muestras no mostraron crecimiento bacteriano. Consideraciones finales: La solución de NaCl al 30% deshidrata la piel, pero no altera significativamente la forma y estructura, además no tiene olor ni toxicidad, lo que garantiza beneficios para la salud de quienes los manipulan, y dicha concentración de NaCl inhibe eficazmente el crecimiento bacteriano en los tejidos y en la propia solución, demostrando ser eficaz en la conservación.

Molecular Mechanism of Antimicrobial Excipient-Induced Aggregation in Parenteral Formulations of Peptide Therapeutics.

Antimicrobial preservatives are used as functional excipients in multidose formulations of biological therapeutics to destroy or inhibit the growth of microbial contaminants, which may be introduced by repeatedly administering doses. Antimicrobial agents can also induce the biophysical instability of proteins and peptides, which presents a challenge in optimizing the drug product formulation. Elucidating the structural basis for aggregation aids in understanding the underlying mechanism and can offer valuable knowledge and rationale for designing drug substances and drug products; however, this remains largely unexplored due to the lack of high-resolution characterization. In this work, we utilize solution nuclear magnetic resonance (NMR) as an advanced biophysical tool to study an acylated 31-residue peptide, acyl-peptide A, and its interaction with commonly used antimicrobial agents, benzyl alcohol and m-cresol. Our results suggest that acyl-peptide A forms soluble octamers in the aqueous solution, which tumble slowly due to an increased molecular weight as measured by diffusion ordered spectroscopy and 1H relaxation measurement. The addition of benzyl alcohol does not induce aggregation of acyl-peptide A and has no chemical shift perturbation in 1H-1H NOESY spectra, suggesting no detectable interaction with the peptide. In contrast, the addition of 1% (w/v) m-cresol results in insoluble aggregates composed of 25% (w/w) peptides after a 24-hour incubation at room temperature as quantified by 1H NMR. Interestingly, 1H-13C heteronuclear single-quantum coherence and 1H-1H total correlation experiment spectroscopy have identified m-cresol and peptide interactions at specific residues, including Met, Lys, Glu, and Gln, suggesting that there may be a combination of hydrophobic, hydrogen bonding, and electrostatic interactions with m-cresol driving this phenomenon. These site-specific interactions have promoted the formation of higher-order oligomerization such as dimers and trimers of octamers, eventually resulting in insoluble aggregates. Our study has elucidated a structural basis of m-cresol-induced self-association that can inform the optimized design of drug substances and products. Moreover, it has demonstrated solution NMR as a high-resolution tool to investigate the structure and dynamics of biological drug products and provide an understanding of excipient-induced peptide and protein aggregation.

Generic benzalkonium chloride-preserved travoprost eye drops are not identical to the branded polyquarternium-1-preserved travoprost eye drop: Effect on cultured human conjunctival goblet cells and their physicochemical properties.

PURPOSE: To investigate the effect of polyquaternium-1 (PQ)-preserved and benzalkonium chloride (BAK)-preserved travoprost eye drops on viability of primary human conjunctival goblet cell (GC) cultures and on secretion of mucin and cytokines. Furthermore, to evaluate the physicochemical properties of the branded travoprost eye drop Travatan® and available generics. METHODS: The effect of travoprost eye drops was evaluated on GC cultures. Cell viability was assessed through lactate dehydrogenase (LDH) and tetrazolium dye (MTT) colorimetric assays. Mucin secretion was evaluated by immunohistochemical staining. Secretion of interleukin (IL)-6 and IL-8 was measured using BD Cytometric Bead Arrays. pH, viscosity, droplet mass, osmolality and surface tension were measured for all included eye drops. RESULTS: In the LDH assay, BAK travoprost caused significant GC loss after 2 hrs of incubation compared to the control. PQ travoprost caused no GC loss at any time point. Both PQ- and BAK travoprost caused secretion of mucin to the cytoplasma. No difference in IL-6 and IL-8 secretion was identified compared to controls. The pH values for the generics were lower (pH 6.0) than the pH value for Travatan (pH 6.7; p < 0.0001). The viscosity was lowest for Travatan, while the mean droplet mass was higher for Travatan (35 mg) than the generics (28-30 mg; p ≤ 0.0318). The osmolality and surface tension did not differ between the eye drops investigated. CONCLUSION: BAK travoprost caused GC loss, indicating that PQ preservation may be preferable in treatment of glaucoma. Furthermore, physicochemical properties of branded and generic travoprost eye drops can not be assumed to be identical.

Interaction of Aluminum-adjuvanted Recombinant P[4] Protein Antigen With Preservatives: Storage Stability and Backbone Flexibility Studies.

Eight antimicrobial preservatives used in parenteral multidose formulations (thimerosal, 2-phenoxy ethanol, phenol, benzyl alcohol, m-cresol, chlorobutanol, methyl paraben, propyl paraben) were examined for their effects on the storage stability (4 °C, 25 °C) of an Alhydrogel® (AH) adjuvanted formulation of the non-replicating rotavirus vaccine (NRRV) recombinant P[4] protein antigen. The stability of AH-adsorbed P[4] was monitored for antigen-antibody binding, conformational stability, and antigen-adjuvant interaction via competitive ELISA, DSC, and SDS-PAGE, respectively. There was an unexpected correlation between increasing storage stability of the AH-adsorbed P[4] and preservative hydrophobicity (log P) (e.g., the parabens and chlorobutanol were least destabilizing). We used hydrogen exchange-mass spectrometry (HX-MS) to better understand the destabilizing effects of temperature and preservative on backbone flexibility of AH-adsorbed P[4]. Thimerosal addition immediately increased the backbone flexibility across much of the AH-adsorbed P[4] protein backbone (except the N-terminal P2 region and residues G17-Y38), and further increase in P[4] backbone flexibility was observed after storage (4 °C, 4 weeks). HX-MS analysis of AH-adsorbed P[4] stored for 4 weeks at 25 °C revealed structural alterations in some regions of the epitope involved in P[4] specific mAb binding. These combined results are discussed in terms of a generalized workflow for multi-dose vaccine formulation development for recombinant protein antigens.

Integrated approaches to testing and assessment as a tool for the hazard assessment and risk characterization of cosmetic preservatives.

The safety assessment of cosmetic products is based on the safety of the ingredients, which requires information on chemical structures, toxicological profiles, and exposure data. Approximately 6% of the population is sensitized to cosmetic ingredients, especially preservatives and fragrances. In this context, the aim of this study was to perform a hazard assessment and risk characterization of benzalkonium chloride (BAC), benzyl alcohol (BA), caprylyl glycol (CG), ethylhexylglycerin (EG), chlorphenesin (CP), dehydroacetic acid (DHA), sodium dehydroacetate (SDH), iodopropynyl butylcarbamate (IPBC), methylchloroisothiazolinone and methylisothiazolinone (MCI/MIT), methylisothiazolinone (MIT), phenoxyethanol (PE), potassium sorbate (PS), and sodium benzoate (SB). Considering the integrated approaches to testing and assessment (IATA) and weight of evidence (WoE) as a decision tree, based on published safety reports. The hazard assessment was composed of a toxicological matrix correlating the toxicity level, defined as low (L), moderate (M), or high (H) and local or systemic exposure, considering the endpoints of skin sensitization, skin irritation, eye irritation, phototoxicity, acute oral toxicity, carcinogenicity, mutagenicity/genotoxicity, and endocrine activity. In a risk assessment approach, most preservatives had a margin of safety (MoS) above 100, except for DHA, SDH, and EG, considering the worst-case scenario (100% dermal absorption). However, isolated data do not set up a safety assessment. It is necessary to carry out a rational risk characterization considering hazard and exposure assessment to estimate the level of risk of an adverse health outcome, based on the concentration in a product, frequency of use, type of product, route of exposure, body surface location, and target population.

Development of a new, simple, rapid ultra-high-performance liquid chromatography (UHPLC) method for the quantification of 2-phenoxyethanol in vaccines for human use.

A new, simple and rapid method for the quantitative determination of the antimicrobial preservative 2-phenoxyethanol, based on reverse phase ultra-high-performance liquid chromatography has been developed. The validation was performed according the ICH Q2 guideline "Validation of Analytical Procedures". The desired chromatographic separation was achieved on a Waters Symmetry C18 (150 × 4.6 mm, 5 µm) column using an isocratic elution, with detection at 270 nm wavelength. The mobile phase consisted of acetonitrile/water (55:45, v/v), pumped at a flow rate of 1 mL/min. The calibration curve and the analytical procedure are linear (r2 = 0.999) from the concentration of 0.07 mg/mL to 1.1 mg/mL. The percent relative standard deviation for intra- and inter-day precision was <1%. The recovery of 2-phenoxyethanol in vaccines ranged between 96.5 and 100.60%. The limits of detection and quantitation were 1.3 × 10-4 and 2.7 × 10-4 mg/mL, respectively. The method was found to be robust by changing the column working temperature, the percentage of acetonitrile of the mobile phase and the flow rate. The validated method can be successfully and reliably used to quantify as well as to exclude presence of 2-phenoxyethanol preservative in marketed vaccines.

Computational identification of preservatives with potential neuronal cytotoxicity.

Preservatives play a vital role in cosmetics by preventing microbiological contamination for keeping products safe to use. However, a few commonly used preservatives have been suggested to be neurotoxic. Cytotoxicity to neuronal cells is commonly used as the first-tier assay for assessing chemical-induced neurotoxicity. Given the time and resources required for chemical screening, computational methods are attractive alternatives over experimental approaches in prioritizing chemicals prior to further experimental evaluations. In this study, we developed a Quantitative Structure-Activity Relationships (QSAR) model for the identification of potential neurotoxicants. A set of 681 chemicals was utilized to construct a robust prediction model using oversampling and Random Forest algorithms. Within a defined applicability domain, the independent test on 452 chemicals showed a high accuracy of 87.7%. The application of the model to 157 preservatives identified 15 chemicals potentially toxic to neuronal cells. Three of them were further validated by in vitro experiments. The results suggested that further experiments are desirable for assessing the neurotoxicity of the identified preservatives with potential neuronal cytotoxicity.

Ayurvedic formulations containing benzoic and ascorbic acids as additives: benzene formation during storage and impact of additives on quality parameters.

OBJECTIVES: Ayurvedic formulations are becoming the prior choice of people as health care supplements. The increasing demand for these formulations has led to extensive development of Ayurvedic pharmaceutical industries worldwide. The reaction between the preservatives (sodium benzoates and ascorbic acid) used in these formulations could generate benzene. Benzene is classified as class-1 human carcinogen and responsible for various short and long term health effects. METHODS: In this study, 25 formulations (containing ascorbic acid and sodium benzoate) of various manufacturers available as over the counter products were obtained and their benzene content were determined using gas chromatograph with flame ionization detector. RESULTS: The result showed that 64% of the formulations were free from benzene contamination whereas 36% of formulations were found to be contaminated with benzene. A simple, less time-consuming, economic, and validated gas chromatographic method for estimation of benzene in Ayurvedic formulations was also developed successfully in present study. CONCLUSIONS: The data revealed that the level of benzene was within permissible limits, yet the presence of a carcinogen in the marketed formulations intended for internal use is an alarming situation.

Lipophilic Arginine Esters: The Gateway to Preservatives without Side Effects.

This study hypothesized that long carbon chain cationic arginine (Arg) esters can be considered as toxicologically harmless preservatives. Arg-esters with C18 and C24 carbon chains, namely, arginine-oleate (Arg-OL) and arginine-decyltetradecanoate (Arg-DT), were synthesized. Structures were confirmed by FT-IR, 1H NMR, and mass spectroscopy. Both Arg-esters were tested regarding hydrophobicity in terms of log Poctanol/water, critical micelle concentration (CMC), biodegradability, cytotoxicity, hemolysis, and antimicrobial activity against Escherichiacoli (E. coli), Staphylococcusaureus (S. aureus), Bacillussubtilis (B. subtilis), and Enterococcusfaecalis (E. faecalis). Log Poctanol/water of arginine was raised from -1.9 to 0.3 and 0.6 due to the attachment of C18 and C24 carbon chains, respectively. The critical micelle concentration of Arg-OL and Arg-DT was 0.52 and 0.013 mM, respectively. Both Arg-esters were biodegradable by porcine pancreatic lipase. In comparison to the well-established antimicrobials, benzalkonium chloride (BAC) and cetrimide, Arg-esters showed significantly less cytotoxic and hemolytic activity. Both esters exhibited pronounced antimicrobial properties against Gram-positive and Gram-negative bacteria comparable to that of BAC and cetrimide. The minimum inhibitory concentration (MIC) of Arg-esters was <50 µg mL-1 against all tested microbes. Overall, results showed a high potential of Arg-esters with long carbon chains as toxicologically harmless novel preservatives.

High rate of sensitization to Kathon CG, detected by patch tests in patients with suspected allergic contact dermatitis

Abstract Background: Kathon CG, a combination of methylchloroisothiazolinone and methylisothiazolinone, is widely used as preservative in cosmetics, as well in household cleaning products, industrial products such as paints and glues. It has emerged as an important sensitizing agent in allergic contact dermatitis. Objectives: This study evaluated the reactivity to this substance in patients subjected to patch tests at the Dermatology Institute in Bauru, São Paulo from 2015 to 2017 and its correlation with other preservatives, the professional activity and location of the lesions. Methods: The patients were submitted to standard series of epicutaneous tests, standardized by the Brazilian Group Studies on Contact Dermatitis. Results: Out the 267 patients tested, 192 presented positivity to at least one substance and 29 of the patients (15.10%) presented reaction to Kathon CG, with predominance of the female gender (n = 27); main professional activity associated with Kathon CG sensibilization was cleaning (17.24%), followed by aesthetic areas (13.79%) and health care (10.34%). The most prevalent sensitizations among the substances tested were nickel sulphate (56.3%), followed by cobalt chloride (23.4%), neomycin (18.2%), potassium dichromate (17.7%), thimerosal (14.5%), formaldehyde (13.2%), paraphenylenediamine (9.3%), and fragrance mix (8.3%). Study limitations: We do not have data from patients that were submitted to patch test a decade ago in order to confront to current data and establish whether or no sensitization to Kathon CG has increased. Conclusion: High positivity to Kathon CG corroborates the recent findings in the literature, suggesting more attention to concentration of this substance, used in cosmetics and products for domestic use.

Effect of Aluminum Adjuvant and Preservatives on Structural Integrity and Physicochemical Stability Profiles of Three Recombinant Subunit Rotavirus Vaccine Antigens.

A nonreplicating rotavirus vaccine (NRRV) containing 3 recombinant fusion proteins adsorbed to aluminum adjuvant (Alhydrogel [AH]) is currently in clinical trials. The compatibility and stability of monovalent NRRV antigen with key components of a multidose vaccine formulation were examined using physicochemical and immunochemical methods. The extent and strength of antigen-adjuvant binding were diminished by increasing phosphate concentration, and acceptable levels were identified along with alternate buffering agents. Addition of the preservative thimerosal destabilized AH-adsorbed P2-VP8-P[8] as measured by differential scanning calorimetry. Over 3 months at 4°C, AH-adsorbed P2-VP8-P[8] was stable, whereas at 25°C and 37°C, instability was observed which was greatly accelerated by thimerosal addition. Loss of antibody binding (enzyme-linked immunosorbent assay) correlated with loss of structural integrity (differential scanning calorimetry, fluorescence spectroscopy) with concomitant nonnative disulfide bond formation (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) and Asn deamidation (liquid chromatography -mass spectrometry peptide mapping). An alternative preservative (2-phenoxyethanol) showed similar antigen destabilization. Due to limited availability, only key assays were performed with monovalent P2-VP8-P[4] and P2-VP8-P[6] AH-adsorbed antigens, and varying levels of preservative incompatibility were observed. In summary, monovalent AH-adsorbed NRRV antigens stored at 4°C showed good stability without preservatives; however, future formulation development efforts are required to prepare a stable, preservative-containing, multidose NRRV formulation.

Betanin, a Natural Food Additive: Stability, Bioavailability, Antioxidant and Preservative Ability Assessments.

Betanin is the only betalain approved for use in food and pharmaceutical products as a natural red colorant. However, the antioxidant power and health-promoting properties of this pigment have been disregarded, perhaps due to the difficulty in obtaining a stable chemical compound, which impairs its absorption and metabolism evaluation. Herein, betanin was purified by semi-preparative HPLC-LC/MS and identified by LC-ESI(+)-MS/MS as the pseudomolecular ion m/z 551.16. Betanin showed significant stability up to -30 °C and mild stability at chilling temperature. The stability and antioxidant ability of this compound were assessed during a human digestion simulation and ex vivo colon fermentation. Half of the betanin amount was recovered in the small intestine digestive fluid and no traces were found after colon fermentation. Betanin high antioxidant ability was retained even after simulated small intestine digestion. Betanin, besides displaying an inherent colorant capacity, was equally effective as a natural antioxidant displaying peroxy-radical scavenger ability in pork meat. Betanin should be considered a multi-functional molecule able to confer an attractive color to frozen or refrigerated foods, but with the capacity to avoid lipid oxidation, thereby preserving food quality. Long-term supplementation by beetroot, a rich source of betanin, should be stimulated to protect organisms against oxidative stress.

Structural and Molecular Tear Film Changes in Glaucoma.

The Tear Film (TF) is a trilaminar and dynamic fluid covering the entire Ocular Surface (OS), consisting of a mucus, aqueous, and lipid layer deeply interacting between them. Because of its structure and functions, TF plays a pivotal role in the preservation of the OS integrity and the quality of vision. Medical therapy for glaucoma is recognized to profoundly disturb the OS homeostasis by altering all components of the ocular surface unit, including TF. The presence of preservatives, the number of daily eye drops instillations, and the duration of therapy are the main contributors to TF changes. From the physio-pathological side, TF alterations are induced by toxic and allergic mechanisms and result from goblet cell and Meibomian gland loss, dysfunction of accessory lacrimal glands, and epithelial disruption. In detail, TF changes are represented by mucus layer thinning, reduced mucin concentration, aqueous layer volume reduction, and lipid layer thinning with increased tear evaporation. Hyper- osmolarity and instability represent the main hallmarks of these changes and are an expression of a iatrogenic form of dry eye. TF undergoes also molecular modifications that primarily reflect a therapy- or disease-induced inflammatory status of the OS. Over the last years, this field of research aimed a progressively growing interest since molecular variations may be considered as potential candidate biomarkers of glaucoma. The aim of this review is to report the main TF changes occurring during glaucoma, exploring the relationship they may have with the glaucoma-related ocular surface disease and the patient quality of life, and their utility as potential biomarkers of disease.

Peptide Optimization at the Drug Discovery-Development Interface: Tailoring of Physicochemical Properties Toward Specific Formulation Requirements.

Physicochemical properties of peptides need to be compatible with the manufacturing process and formulation requirements to ensure developability toward the commercial drug product. This aspect is often disregarded and only evaluated late in discovery, imposing a high risk for delays in development, increased costs, and finally for the project in general. Here, we report a case study of early physicochemical peptide characterization and optimization of dual glucagon-like peptide 1/glucagon receptor agonists toward specific formulation requirements. Aggregation issues which were observed at acidic pH in the presence of phenolic preservatives could be eliminated by modification of the peptide sequence, and chemical stability issues were significantly improved by addition of stabilizing formulation excipients. We describe structural, analytical, and biophysical characterization in different compositions to analyze the effect of pH and formulation excipients on physical and chemical stability. Molecular models have been generated to rationalize peptide stability behavior based on computed physicochemical descriptors and interactions with excipients. To conclude these studies, a general roadmap is proposed how to assess and optimize early physicochemical peptide properties in a sophisticated way by combining experimental and in silico profiling to provide stable peptide drugs under relevant formulation conditions at the end of discovery.

New Classes of Polycationic Compounds as Preservatives for Ophthalmic Formulations.

PURPOSE: The purpose of this research work was to develop new polycationic compounds based on pyridine and piperidine structures with high antimicrobial activities against bacteria and fungi. Furthermore, the compounds should offer a lower toxicity than the commonly used preservatives for ophthalmic formulations, such as benzalkonium chloride (BAC) and polyquaternium-1 (PQ1). METHODS: Two polymers and three dimeric compounds were developed. Minimum inhibitory concentrations were determined for Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Candida albicans and Aspergillus brasiliensis. The compounds were characterized regarding their impact on cell viability, cytotoxicity, epithelial integrity and surface tension. MTT and CytoTox-Glo™ assays, permeation studies with mannitol and transepithelial electrical resistance (TEER) measurements were performed on human corneal epithelial or MDCK I cells. BAC and PQ1 were used as references. RESULTS: Three polycationic compounds exhibited high antimicrobial activity against the tested microorganisms comparable to that of BAC. Four compounds were tolerated as well as or better than PQ1. In addition, the TEER, permeability and surface tension were only affected by compounds with amphiphilic properties. CONCLUSION: The pyridine- and piperidine-based polycationic compounds are promising candidates as new preservatives for ophthalmic formulations. Their high antimicrobial efficacy and good tolerability indicate a different mechanism of action compared to BAC.

Efficacy and safety of low-concentration, bisulphite-containing, intracameral epinephrine and topical atropine treatments for the prevention of intraoperative floppy iris syndrome.

PURPOSE: The aim of this study was to evaluate the efficacy and safety of topical atropine and topical atropine combined with intracameral low-concentration, bisulphite-containing epinephrine treatment for the prophylaxis of intraoperative floppy iris syndrome. MATERIALS AND METHODS: Seventy-two eyes of 55 male patients who were treated with alpha-adrenergic antagonist medications for benign prostatic hyperplasia were included in this study. Standard premedication with topical cyclopentolate, phenylephrine, tropicamide and ketorolac was applied to all of the patients. In 22 cases no further prophylactic method was used (Group-NP), while in 29 cases topical atropine drops was instilled 12 h and 30 min before surgery (Group-A) and in 21 cases 1:16 000 epinephrine was injected to the anterior chamber at the beginning of surgery (Group-EA) in addition to topical atropine prophylaxis. RESULTS: In Group-NP, 62.8% of the cases developed IFIS, while development of IFIS was significantly lower in Group-A (17.2%, p = 0.0004) and Group-EA (9.5%, p < 0.0001). Posterior capsule rupture was observed in two cases (9.1%) in Group-NP, in one case (3.4%) in Group-A and was not observed in Group-EA. There was no statistically significant difference between the groups for the development of surgical complications. We did not observe any adverse events or significant endothelial cell loss (p = 0.462). CONCLUSIONS: Our results indicate that preoperative use of topical atropine reduces the incidence of IFIS. Use of low-concentration, bisulphite-containing epinephrine is more effective in the prevention of IFIS and does not cause preservative related endothelial damage. This prophylaxis may be preferred when preservative free epinephrine is not available.

Lippia origanoides essential oil: an efficient and safe alternative to preserve food, cosmetic and pharmaceutical products.

AIMS: The aim of this work was to evaluate the efficacy and safety of Lippia origanoides essential oil as a preservative in industrial products. METHODS AND RESULTS: The composition, antimicrobial activity, mutagenic and toxic potential of L. origanoides were determined. Then, the effect of essential oil as a preservative in food, cosmetics and pharmaceutical products was evaluated. The essential oil of L. origanoides consisted mainly of oxygenated monoterpenes (38·13%); 26·28% corresponded to the compound carvacrol. At concentrations ranging from 0·312 to 1·25 µl ml-1 and in association with polysorbate 80, the essential oil of L. origanoides inhibited the growth of all the tested micro-organisms. The medium lethal dose in mice was 3·5 g kg-1 , which categorizes it as nontoxic according to the European Union criteria, and negative results in the Ames test indicated that this oil was not mutagenic. In combination with polysorbate 80, the essential oil exerted preservative action on orange juice, cosmetic and pharmaceutical compositions, especially in the case of aqueous-based products. CONCLUSIONS: Lippia origanoides essential oil is an effective and safe preservative for orange juice, pharmaceutical and cosmetic products. SIGNIFICANCE AND IMPACT OF THE STUDY: This study allowed for the complete understanding of the antimicrobial action and toxicological potential of L. origanoides essential oil. These results facilitate the development of a preservative system based on L. origanoides essential oil.

Thinned stone fruits are a source of polyphenols and antioxidant compounds.

BACKGROUND: Thinned fruits are agricultural by-products that contain large quantities of interesting compounds due to their early maturity stage. In this work, the phenolic profile and the antioxidant activity of six thinned stone fruits (apricot, cherry, flat peach, peach, plum and nectarine) have been investigated, focussing on proanthocyanidins. RESULTS: Thinned nectarine had the highest content of total phenols [67.43 mg gallic acid equivalents (GAE) g-1 dry weight (DW)] and total flavonoids (56.97 mg CE g-1 DW) as well as the highest antioxidant activity measured by DPPH scavenging (133.30 mg [Trolox equivalents (TE) g-1 DW] and FRAP assay (30.42 mg TE g-1 DW). Proanthocyanidins were very abundant in these by-products, and the main phenolic group quantified in cherry (10.54 mg g-1 DW), flat peach (33.47 mg g-1 DW) and nectarine (59.89 mg g-1 DW), while hydroxycinnamic acids predominate in apricot, peach and plum (6.67, 22.04 and 23.75 mg g-1 DW, respectively). The low, mean degree of polymerisation of proanthocyanidins suggests that their bioavailability could be very high. CONCLUSIONS: This study shows that thinned stone fruit extracts might be used as antioxidants in foods or as a source of compounds with health-related benefits that can be used in the pharmaceutical, cosmetic and food industries. © 2016 Society of Chemical Industry.

Stability of (-)-epigallocatechin gallate and its activity in liquid formulations and delivery systems.

(-)-Epigallocatechin gallate (EGCG) has become a popular disease-preventive supplement worldwide because it may aid in slowing down the onset of age-related diseases such as cancer, diabetes and tissue degeneration. As largely demonstrated in cell culture studies, EGCG possesses antioxidant properties and exhibits favorable effects on gene expression, signal transduction and other cell functions. However, only limited effects have been observed in experimental animals and human epidemiological studies. The inconsistency between the biological activity of EGCG in cell cultures and in vivo can be attributed to its low stability, which not only decreases its bioavailability but also leads to the formation of degradation products and prooxidant molecules with possible side-effects. Understanding EGCG degradation kinetics in solution and in vivo is crucial for its successful clinical application. Ambient conditions (pH, temperature, oxygen) can either enhance or decrease the stability of EGCG, thus influencing its biological activity. Usage of stabilizers and/or encapsulation of EGCG into particulate systems such as nanoparticles or microparticles can significantly increase its stability. In this review, the effects of ambient conditions, stabilizers and encapsulation systems on EGCG stability, activity and degradation rate are illustrated.

Does preservative content affect drug permeability? The permeability analysis in vitro of 3 ophthalmic Latanoprost formulations in a human epithelial cell culture model. / Czy przenikalnosc leku jest uwarunkowana zawartoscia srodka konserwujacego? Analiza in vitro na modelu komórkowym nablonka ludzkiej rogówki przenikalnosci trzech preparatów okulistycznych zawierajacych latanoprost.

Aim: Comparative permeability analysis of the 3 following Latanoprost formulations intended for ophthalmic use: Xaloptic (Pol­pharma S.A.), Xalatan (Pfizer Europe MA EEIG) and Monoprost (Thea Pharma S.A.) across human corneal epithelium (HCE-T culture model) in vitro. Material and methods: Permeability analysis was performed under conditions suitable for latanoprost API (active pharmaceutical ingredient). Statistical analysis of permeability and drug quantity after passing across a cellular membrane was performed using ANOVA test and Tukey's multiple comparison test (GraphPad Prism 6.00 for Windows, GraphPad Software, La Jolla California, USA Results: The following differences in permeability were noted between the analyzed drugs: The permeability rates for Xaloptic and Xalatan were 5.49 ± 1.64 x 10-6 cm/s and 4.66 ± 1.13 x 10-6 cm/s, respectively. Xaloptic showed the highest permeability through human corneal epithelium (23.70 ± 1.71 x 10-6 cm/s) and the highest conversion rate (28.13 ± 5.85%). As compared to Xaloptic, Xalatan slight, yet statistically significant differences with the permeability rate of 21.21 ± 1.29 x 10-6 cm/s and a conversion rate of 18.41 ± 2.96%). Monoprost demonstrated the lowest permeability (0.39 ± 0.07 x 10-6 cm/s) and the lowest conversion rate (0.34 ± 0.16%). Conclusion: The differences in permeability and bioavailability between the 3 ophthalmic latanoprost formulations are attributable to the differences in their composition. They are also related to the content of preservative in each preparation.