Medicinal plants used as excipients in the history in Ghanaian herbal medicine

ETHNOPHARMACOLOGICAL RELEVANCE

The present study was carried out to investigate the traditional use, pharmacology and active compounds of four plants commonly used as excipients in herbal medicine in Ghana.

MATERIALS AND METHODS

A comprehensive literature search was conducted to gain knowledge about the traditional use, pharmacology and active compounds of the four plant excipients. The broth dilution antibacterial assay and the DPPH radical scavenging antioxidant assay were used to evaluate the antibacterial and antioxidant activity of the plants, respectively. Ethanol, warm water and cold water extracts were prepared from the dried seeds/fruits of Aframomum melegueta, Piper guineense, Xylopia aethiopica and Monodora myristica, and tested in the assays.

RESULTS

A. melegueta and P. guineense seemed to act as pharmacoenhancers, since they have been shown to inhibit specific CYP-enzymes. A. melegueta could act as an antioxidant to preserve herbal preparations. None of the plant excipients had antibacterial activity against the bacteria tested in this study. Compounds with an aromatic or pungent smell had been identified in all the plant excipients. An explanation for the use of the plants as excipients could rely on their taste properties.

CONCLUSION

The present study suggests that there may be more than one simple explanation for the use of these four plants as excipients. Plausible explanations have been proven to be: (1) a way to increase the effect of the medicine, (2) a way to make the medicine more palatable or (3) a way to preserve the activity of the medicinal preparation over time.

Survey of studies on microbial contamination of marketed tattoo inks

Tattooing became a popular phenomenon during the late twentieth century. Because the act of tattooing involves repeated injection of ink through the skin, a risk of contracting infections from contaminated tattooing equipment and ink and the surrounding environment exists. Progress has been made in infection control strategies; however, contraction of bacterial and viral infections from tattooing continues to occur. The risk of acquiring a tattoo-related infection largely depends on the hygiene conditions under which the tattoo is applied. Nevertheless, even when adequate hygiene and sanitation measures are taken, the inks themselves may contain infectious microorganisms that are able to survive under hostile conditions, such as in inks. The results of the few studies on the microbiological quality of unopened and opened tattoo inks are reported. Some authors' conclusions demonstrated that the current ink sterilisation systems show a low capability to inactivate microbial contamination in tattoo inks. At the moment, European Resolution ResAP2008-1 recommends that the ink be sterile and supplied in containers that maintain the sterility of the product until application. In light of the outcomes of published studies, at the moment, preservation of the microbial quality and safety of ink seems challenging and still difficult to reach.

Making innovative tattoo ink products with improved safety: possible and impossible ingredients in practical usage

Today's tattoo inks are no longer just simple solids in liquid suspension. Nowadays, these inks are high-tech dispersions made from finely spread pigments in a binder-solvent mixture. These so-called colour dispersions must follow the modern standards of tattooing, which are increasing every year. They must be rich in chromophoric pigments and yet fluid, they must not dry rapidly, and there should be no occurrence of any sedimentation, even during longer tattoo seasons. An innovative tattoo ink should enable long-lasting, brilliant tattoos without a negative impact on the artist's workflow and of course without endangering the consumer. The high standard in tattoos, regarding the motives and techniques, that is witnessed today could not be achieved by the artists without quality tools and modern tattoo ink. This article will give the reader a brief overview of the different ingredients of tattoo ink and of the function of binding agents and solvents in modern tattoo ink as well as describe what additives are used to achieve the desired behaviour during application. Furthermore, the article will take a look into the pigments that are used in tattoo ink and show why certain pigments are not suited for tattoo ink. The differences, advantages and disadvantages of organic and inorganic pigments will be explained.

Intraocular pressure decrease with preservative-free fixed and unfixed combination of tafluprost and timolol in pseudoexfoliative glaucoma

We investigated the intraocular pressure (IOP) lowering efficacy of preservative-free fixed and non-fixed combination of tafluprost 0.0015% and timolol 0.5% in pseudoexfoliative glaucoma (XFG). A per protocol worse eye analysis was made on all XFG patients who participated in a recent 6 month, prospective, randomized, double-masked, parallel group, multicenter phase III study. The mean time-wise IOP decreased by 8.62 to 10.25 mmHg (31.8 to 36.7%) in the fixed dose combination arm (15 patients) and by 5.38 to 11.35 mmHg (21.3 to 41.2%) in the non-fixed combination arm (13 patients), respectively (p < 0.001 for all comparisons). The results show that a preservative-free fixed dose combination of tafluprost and timolol provides a clinically significant IOP reduction in XFG, and may offer an advantage for the XFG patients with dry eye, due to its preservative-free nature.

Methylisothiazolinone contact allergy is rising to alarming heights also in southern Sweden

The preservative methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) is a well-known sensitiser and present in most baseline series since at least 20 years. The proportions of MCI/MI are 3:1. MI alone has been used as a preservative in occupational and household products, and cosmetics since less than 10 years. MCI/MI tested at 100 ppm fails to detect a significant percentage of contact-allergic reactions to MI. Our aim was to investigate whether a separate test preparation with MI picks up additional cases of contact allergy to MI not detected with MCI/MI 200 ppm. MI was inserted into the baseline series of the Malmö clinic in 2003 starting at 475 ppm, then 900 ppm, then 1,000 ppm, 1,500 ppm and finally 2,000 ppm. In 5,881 consecutively tested dermatitis patients the contact allergy rate for MI varied between 0.5 and 6.5%, with a marked increase in recent years. The contact allergy rate to MI 2,000 ppm alone, not traced by MCI/MI 200 ppm, varied between 0 and 1.9 %. In conclusion, due to the increase of contact allergy to MI not traced by MCI/MI 200 ppm, MI in water at 2,000 ppm should be tested in a baseline series. Independent of patch test technique a dose of 60 µg/cm should not be exceeded to avoid adverse reactions and particularly patch test sensitisation.

A 6-month study comparing efficacy, safety, and tolerability of the preservative-free fixed combination of tafluprost 0.0015% and timolol 0.5% versus each of its individual preservative-free components

Introduction

The efficacy, safety and tolerability of the preservative-free (PF) fixed combination (FC) of tafluprost 0.0015% and timolol 0.5% (once daily) were compared to those of the individual components (PF tafluprost 0.0015% once daily and PF timolol 0.5% twice daily) in patients with open-angle glaucoma or ocular hypertension inadequately controlled on prior timolol or prostaglandin monotherapy for 6 months.

Methods

A stratified, double-masked, randomized, multicenter phase III study was conducted. A total of 189 prior timolol users were randomized within the timolol stratum (TS) to receive either FC (n = 95) or timolol 0.5% (TIM; n = 94). Furthermore, a total of 375 prior prostaglandin analog (PGA) users were randomized within the prostaglandin stratum (PS) to receive either FC (n = 188) or tafluprost 0.0015% (TAF; n = 187). To be eligible for participation in the study, the patients were required to have an intraocular pressure (IOP) of ≥22 mmHg when on timolol (TIM) or of ≥20 mmHg when on PGA in either treated eye at the screening and end-of-run-in visits. In addition to these, the study included visits at baseline, 2 and 6 weeks, 3 and 6 months and at a post-study visit. IOP was measured at 8 a.m., 10 a.m., 4 p.m., and 8 p.m.

Results

In the TS, a significant reduction from baseline IOP was seen with FC and TIM throughout the study. Average diurnal IOP change from baseline at month 3 was −8.55 mmHg (32%) for FC and −7.35 mmHg (28%) for TIM. The model-based treatment difference (FC–TIM) was −0.885 mmHg [95% confidence interval (CI) −1.745 to −0.024; p = 0.044] demonstrating the superiority of FC over TIM. In the PS, a significant reduction in IOP was seen with both FC and TAF throughout the study. The average diurnal IOP change from baseline at month 3 was −8.61 mmHg (33%) for FC and −7.23 mmHg (28%) for TAF. The model-based treatment difference (FC–TAF) was −1.516 mmHg (95% CI −2.044 to −0.988; p < 0.001) demonstrating the superiority of FC over TAF. In the TS, related ocular adverse events (AEs) were more frequent for patients treated with FC compared to TIM (16.8% versus 6.4%), whereas related non-ocular AEs were more frequent with TIM compared to FC (2.1% versus 0.0%). In the PS, AEs were similarly distributed between FC and TAF. The frequency of conjunctival hyperemia of FC was low (6.4%).

Conclusion

The preservative-free fixed combination of tafluprost and timolol provided a substantial and significant IOP reduction in both strata. The IOP reduction was superior to both tafluprost 0.0015% and timolol 0.5% when given as monotherapies. Overall, the study treatments were safe and well tolerated.

Funding

Santen Oy, Tampere, Finland.

Electronic supplementary material

The online version of this article (doi:10.1007/s12325-014-0163-3) contains supplementary material, which is available to authorized users.

Fixed-dose combination of tafluprost and timolol in the treatment of open-angle glaucoma and ocular hypertension: comparison with other fixed-combination products

A new preservative-free fixed-dose combination of 0.0015% tafluprost, a prostaglandin F_2α analog, and 0.5% timolol (TAF/TIM; Santen Oy, Tampere, Finland), a beta-adrenergic antagonist has recently been developed. The intraocular pressure (IOP) reduction with TAF/TIM in open-angle glaucoma and ocular hypertension is similar to that of other prostaglandin–timolol fixed-combination products. Patients with high IOP responded well to TAF/TIM with reductions of up to 40% (>13 mmHg) and beyond. Compared to previous controlled and double-masked clinical trials with DuoTrav^® (Alcon, Fort Worth, USA) and Ganfort^® (Allergan, Irvine, USA), TAF/TIM caused less superficial ocular side effects and less conjunctival hyperemia. Plausible explanations for the differences in side effects between the fixed-combination products are discussed.

Parents' preferences for seasonal influenza vaccine for their children in Japan

In Japan, trivalent inactivated influenza vaccine is the only approved influenza vaccine. It is typically administrated by hypodermic injection, and children under 13 years of age are recommended to be vaccinated two times during each winter season. Live-attenuated influenza vaccine (LAIV) is administered by a thimerosal-free nasal spray. If LAIV is approved in the future in Japan, parents will have an alternative type of influenza vaccine for their children. This study investigated parents' preference for the type of seasonal influenza vaccine for their children if alternatives are available. The marginal willingness to pay for vaccine benefits was also evaluated. We conducted a discrete choice experiment, a quantitative approach that is often used in healthcare studies, in January 2013. Respondents were recruited from a registered online survey panel, and parents with at least one child under 13 years of age were offered questionnaires. This study showed that for seasonal influenza vaccines for their children, parents are more likely to value safety, including thimerosal-free vaccines and those with a lower risk of adverse events, instead of avoiding the momentary pain from an injection. If LAIV is released in Japan, the fact that it is thimerosal-free could be an advantage. However, for parents to choose LAIV, they would need to accept the slightly higher risk of minor adverse events from LAIV.

Nanosuspensions of hesperetin: preparation and characterization

Nanosuspensions are a smart formulation principle for dermal applications, as they increase the penetration of poorly soluble substances into the skin. Because microbial stability is a pre-requisite for dermal formulations, water containing formulations need to be preserved. Preservatives are known to possibly impair the physical stability of disperse systems, i.e. by causing agglomeration. These aggregation phenomena might occur during storage of the final product, but can already occur during the production process itself. Therefore, in this study the influence of six different preservatives on the diminution efficiency during the production of hesperetin nanocrystals was investigated. Particles with and without the addition of preservatives were produced by high pressure homogenization (HPH) and the final particle size was analysed and compared to the non-preserved suspension. All preservatives influenced the diminution progress during production and the final particle sizes obtained. The non-preserved suspension yielded a particle size of about 300 nm. Preservation with Hydrolite, Euxyl PE9010, Rokonsal and Phenonip led to sizes of about 400 nm. Preservation with Caprylyl glycol and MultiEx did not lead to nanoparticles (size > 1 microm) and caused a slight agglomeration of the nanosuspensions. Based on zeta potential measurements it was found that the impairment is related to the lipophilicity of the presverative, i.e. the lower the lipophilicity, the less is the impairment. In conclusion, preservatives impair the diminution efficacy during the production of nanosuspensions. Therefore, if possible, preservatives should be added to nanosuspensions after the production process. If preservatives are required during production, highly hydrophilic preservatives, e.g. Hydrolite E, should be used.

Conjunctival goblet cells density and preservative-free tafluprost therapy for glaucoma: an in vivo confocal microscopy and impression cytology study

PURPOSE

To evaluate the density of conjunctival goblet cells (GCs) in glaucomatous patients treated with preservative-free (PF) tafluprost, using laser scanning confocal microscopy (LSCM) and impression cytology (IC).

METHODS

Thirty glaucomatous patients (30 eyes) naive for therapy and thirty healthy subjects (30 eyes) were enrolled. Conjunctiva was examined by means of Heidelberg Retina Tomography/Rostock cornea module. Afterwards, the specimens for IC were obtained. Patients were randomized to PF-tafluprost (Group 1) or preserved latanoprost (Group 2) and controls to the vehicle of latanoprost (Group 3) or physiological buffered saline solution (Group 4). Both LSCM and IC were performed at baseline, and after the 1st and 6th months of therapy, GC density (GCD) (cells/mm(2) ) was the main outcome measurement.

RESULTS

  Baseline. Mean GCD was 240.69 ± 25.43 and 232.65 ± 23.52, for LSCM, and 162.10 ± 23.44 and 164.71 ± 21.03 for IC in Group 1 and 2, respectively. GC density values were not significantly different in Group 3 and 4 (p > 0.05%). Month one. Mean GCD increased to 284.16 ± 43.88 and 230.62 ± 48.32 in Group 1 (p < 0.001) and to 297.86 ± 26.87 and 221.78 ± 43.02 in Group 2 (p < 0.05), measured with LSCM and IC, respectively. In Group 3, GCD decreased to 205.88 ± 25.04 and 139.54 ± 17.37 measured with LSCM and IC, respectively (p < 0.05). Month six. Mean GCD did not change in Group 1 (p > 0.05) whereas it decreased in Group 2 (p < 0.05), compared to month 1. In Group 3, GCD further decreased to 166.32 ± 22.31 and 120.76 ± 11.66, measured with LSCM and IC, respectively (p < 0.05); in Group 4, mean GCD did not change during the study period (p > 0.05).

CONCLUSIONS

Treatment with PF tafluprost was associated with an increase in conjunctival GCD in glaucomatous eyes naïve for therapy. Further studies are mandatory to verify this finding because its validation may have important consequences in the medical management of glaucoma.

[Investigation of the influence of intracameral injection of domestic lidocaine on the corneal thickness during phacoemulsification of cataract]

Influence of intracameral injection of 0.5 % solution of lidocaine hydrochloride on the cornea was investigated. It was proved that 0.5 % solution of lidocaine hydrochloride being preservative-free, has not any adverse effect on the corneal thickness measured by keratopachimetry before and after injection of medicine.

Safety and immunogenicity of a split-virion AS03A-adjuvanted A/Indonesia/05/2005 (H5N1) vaccine in Taiwanese adults

BACKGROUND/PURPOSE

This study evaluated the immune response elicited by two formulations of an AS03(A)-adjuvanted H5N1 A/Indonesia/05/2005 prepandemic influenza vaccine, developed using manufacturing processes with or without thiomersal. In addition, it also evaluated compliance to the Centre for Biologics Evaluation and Research and Committee for Medicinal Products for Human Use (CHMP) immunogenicity guidance criteria for pandemic influenza vaccines in adults.

METHODS

This phase III, observer-blind, randomized study (NCT00812981) enrolled 320 subjects aged 18-60 years into two groups to receive, 21 days apart, two doses of the formulation manufactured using either the thiomersal-containing process (Group TC) or the thiomersal-free process (Group TF). Blood samples collected before vaccination, 21 days after the second vaccine dose, and 6 months following the first vaccine dose (Days 0, 42, and 180) were analysed using a hemagglutination inhibition (HI) assay. Safety assessments were made for the entire study period.

RESULTS

Twenty-one days after the second dose of vaccine, both groups met the CHMP criteria for vaccine-homologous HI response (seroprotection rates/seroconversion rates ≥ 98.7%, seroconversion factor ≥ 121.9) and also for a heterologous HI response against the A/Vietnam/1194/2004 strain (seroprotection rates/seroconversion rates ≥ 81.3%, seroconversion factor ≥ 10.8). Six months after the first dose of vaccine, a marked persistence of the vaccine-homologous HI response was observed that still met one or more CHMP criteria. Pain at the injection site (Group TF 95%, Group TC 91.8%) and myalgia (Group TF 68.8%, Group TC 63.5%) were the most frequently recorded solicited symptoms. Overall, both formulations had a clinically acceptable safety profile.

CONCLUSION

Administration of two doses of the AS03(A)-adjuvanted H5N1 prepandemic influenza vaccine was found to be highly immunogenic in adults with a clinically acceptable safety profile. The ability to confer cross-clade protective immunity makes it a suitable option for mitigation of the morbidity and mortality of outbreaks and pandemics due to H5N1 and drifted strains.

Developing a modified preservative efficacy testing approach as a predictive tool for the evaluation of preservative systems in liquid home care products under variable test conditions

How can a formulator have confidence that a preservative system will perform as expected under adverse conditions? Extreme conditions that can lead to the development of "off odors" in the product can be a serious challenge for companies providing home care products in the global market. Formulation and stability testing occur under controlled parameters that simulate limited environmental conditions and microbial challenges are typically performed with a standard inoculum level. While this is an acceptable and dependable process, it does not necessarily assess how well a preservative system can perform under extreme environmental conditions or against unusually high levels of bacterial challenges. This is especially true when formulations are diluted and stored by the end-user. By modifying microbial challenge testing of a liquid dishwashing product to include unexpected dilution schemes, increased microbial assaults, and elevated temperatures, a pattern of preservative efficacy was established. The resulting approach proved to be a useful tool when developing use directions, recommended dilution levels, the overall surfactant system, preservative type, and storage restrictions.

The frequency of contact allergy in children and adolescents in the Czech Republic

The objective of our study was to determine the prevalence of contact hypersensitivity in asymptomatic Czech schoolchildren. We recruited 236 Prague asymptomatic schoolchildren for epicutaneous tests. The children were tested with European baseline series (25 allergens). A total of 218 children (114 boys and 104 girls) completed the study. Of these, 67 (30.7%) children had one or more positive reactions to tested allergens. Nickel, neomycin and potassium dichromate were the most prevalent allergens detected in our study. Our findings may support the notion that allergic contact sensitization in children is not so rare and children, especially those with chronic dermatitis, should be patch tested regularly.

Resveratrol nanosuspensions: interaction of preservatives with nanocrystal production

The effect of six different preservatives on the production process and stability of resveratrol nanosuspensions was investigated. Nanosuspensions of the anti-oxidant resveratrol were prepared by high pressure homogenization (1,500 bar, 20 homogenization cycles). The preservatives used were: caprylyl glycol (0.75%), Euxyl PE 9010 (1.0%), Hydrolite-5 (2.0), Phenonip (0.75%), Rokonsal PB-5 (0.5%) and MultiEx Naturotics (2.0%). Preservation is essential for oral and dermal nanosuspensions, but can impair the stability. The effect of the preservatives on stability as a function of cycle numbers was determined by size measurements (photon correlation spectroscopy (PCS), laser diffraction (LD) and light microscopy). Zeta potential measurements were performed for determination of the Stern potential (measurements in water) and as stability criterion (measurements in original dispersion medium), to elucidate the mechanism of destabilization. The preservatives could be placed into three groups. Hydrolite-5 did not affect the production process and the short term stability, sizes were practically identical to the preservative-free nanosuspension (e.g. PCS diameters 196 nm and 184 nm, respectively). All other preservatives impaired the stability medium to pronounced, being most pronounced for MultiEx Naturotics. Hydrolite-5 is recommended as preservative of choice. A mechanistic model was developed to explain the absence and the different degrees of destabilization. In general, when screening for suitable preservatives, suspensions are produced, different preservatives added and the size changes are monitored over long-term. The destabilizing effect of the preservatives on nanosuspensions became evident when added in the production process immediately, thus this can be used as a screening tool for optimal, non-destabilizing preservatives, replacing or minimizing time-consuming long-term stability studies.

The solubilisation and inactivation of preservatives by non-ionic detergents

A novel potentiometric method, which depends on the pH changes which occur when an acidic material is solubilised, has been used to determine the solubilisation of the weakly acidic preservative, p-hydroxybenzoic acid, in a non-ionic detergent. From the pH changes observed, the partition coefficient, Km, for the distribution of the un-ionised acid between the micellar and the aqueous phase has been calculated and found to be 2.8 × 103. Specific interaction between the acid and the detergent. to form a complex is shown not to be important. It is suggested that the arguments against specific interaction apply generally to other preservatives and non-ionic detergents.

Applicability of the Ferguson principle to systems of mixed preservatives

Using solubility and distribution data for methyl and propyl p-hydroxybenzoates, the degree of saturation of the aqueous phase of an oil-in-water emulsion has been calculated for various oil: water ratios. In emulsions of low oil content the propyl ester gives the higher degree of saturation of the aqueous phase, while in emulsions of high oil content the methyl ester gives the higher degree of saturation. Irrespective of the oil: water ratio, a mixture of the esters cannot give a higher degree of saturation or a higher thermodynamic activity of the aqueous phase, than either ester alone. The finding of many investigators that mixtures of the esters have higher biological activities than a single ester must therefore depend, not only on the degree of saturation, or thermodynamic activity of the aqueous phase, but also on some other unknown factors.

Preservative system development for argan oil-loaded nanostructured lipid carriers

Nanostructured lipid carriers (NLC) are used in many dermal cosmetic formulations. To prevent microbiological spoilage of NLC suspensions preservative systems must be used. Preservatives can impair the physical stability of NLC suspensions. Therefore, a systematic screening of preservative systems should be performed and the compatibility of these preservative systems with each NLC formulation has to be investigated. In this study three Argan oil-loaded NLC formulations were developed. Ethanol, propylene glycol and pentylene glycol were admixed to these formulations as preservative systems. The physical stability of the non-preserved and preserved formulations has been investigated. Upon admixing 20% w/w ethanol to the selected formulations, immediate particle aggregation could be detected using laser diffractometry and after 24 hours gelling occurred. This was accompanied with a lowering of Zeta potential value. Samples preserved with 10% w/w propylene glycol did not show any change in particle size or in Zeta potential, in comparison to the non-preserved formulation, when measured after one day and 120 days. Samples preserved with 5% pentylene glycol proved also to be stable after 120 days and did not show any change in particle size or Zeta potential.

[Advances in preservative-free glaucoma drops]

Ophthalmic solutions are the main therapeutic methods used in the treatment of ocular diseases, including glaucoma. Preservatives are added in multidose solutions to reduce the risk of microbial contamination. Repeated use of topical medication, especially in patients treated for glaucoma, has many adverse effects especially on the ocular surface. This paper provides an overview of the role of preservatives in antiglaucoma preparations, and their impact on the ocular surface.

Evaluation of preservative effectiveness of liquid crystalline systems with retynil palmitate by the challenge test and D-value

The objective of this work was to evaluate the preservative effectiveness of liquid crystalline systems containing retynil palmitate (RP) by the challenge test (CT) and D-value. A system was developed containing water, silicon glycol copolymer, and polyether functional siloxane with 1% RP added. The analyses were carried out by methods in the U.S. Pharmacopeia (USP 31, 2008) using the microorganisms Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, and Aspergillus niger. The CT showed that after 7 days, all microorganisms were eliminated except A. niger, which maintained viability for at least 28 days after inoculation. Moreover, the microorganisms E. coli, P. aeruginosa, S. aureus, C. albicans, and A. niger presented different growth behaviors, evidenced by differences among the D-values calculated. It was concluded that the CT and D-value were efficient methods for evaluation of the preservative property of these formulations.

Evaluation of different preparation methods for a preservative free triamcinolone acetonide preparation for intravitreal administration: a validated stability indicating HPLC-method

Intravitreally applied triamcinolone acetonide (TA) is used to treat a variety of macular diseases. Commercially available products of TA are mainly intended for intramuscular application and contain benzyl alcohol (BA) as a bacteriostatic preservative. Since this agent damages ocular tissues, different methods such as filtration techniques and centrifugation are usually used to eliminate BA from commercial products (40 mg/mL TA, 9.9 mg/mL BA). In this study, we evaluated these methods in regard to their ability to eliminate benzyl alcohol and to guarantee standard doses of triamcinolone acetonide. A new formulation without BA (TA 40 mg/mL) was developped according to the following criteria: autoclavability, stability, and suitability for intravitreal use. For QA/QC evaluation a new rapid and simple HPLC procedure (C18 RP column, mobile phase consisting of methanol-water, 48:52, v/v) to quantify the respective compounds was developed and validated according to ICH guidelines. The HPLC method was proven to be selective, linear, precise and accurate. Analysis of preparations based on commercial products undergoing different filtration techniques showed variable results: TA concentrations of 22-80% of the declared amount were found, and BA content was not reduced to safe levels (up to 39% of initial content remained). Centrifugation methods decreased the concentration of the preservative adequately, however agglomerated TA crystals were observed, leading to irreproducible and deviating particle sizes that are potentially harmful with ocular use. The newly developed preservative free formulation (TA 40 mg/mL) delivered uniform doses of TA, revealed no drug loss during forced light exposure and was proven to be stable, sterile and bacterial endotoxin free after autoclaving and after storage for three months,. The new formulation may offer an alternative for the in-house production of intravitreally applicable TA preparations in hospital pharmacies and should enhance medication safety.

IOP-lowering efficacy and tolerability of preservative-free tafluprost 0.0015% among patients with ocular hypertension or glaucoma

OBJECTIVE

Tafluprost, the first preservative-free prostaglandin analogue for topical ophthalmic use to lower IOP, was introduced in Germany in 2008. After the approval for ophthalmic use, an open-label, multicentre, observational study was conducted between October 2008 and April 2009. Major objectives of this study were to evaluate the real world efficacy, local tolerability and safety of this first in class preservative-free prostaglandin preparation in patients with ocular hypertension and glaucoma.

METHODS

A total of 544 patients were treated with the preservative-free formulation of tafluprost 0.0015%. The majority of these patients had poor IOP control and/or poor local tolerance of their medication prior change of medication. The decision to change the previous therapy or to initiate treatment was made solely by the participating ophthalmologists. IOP readings were recorded at baseline before changing medication or initiating treatment in newly diagnosed patients, 4-6 weeks and 12 weeks after change of medication or initiation of treatment with preservative-free tafluprost. In addition, patient demographics, subjective symptoms (i.e. burning, foreign body sensation, itching and stinging) and objective clinical signs such as conjunctival hyperaemia were collected. Subjective symptoms were evaluated using a 4 point scale ranging from 'no symptoms', 'mild symptoms', 'moderate symptoms' to 'severe symptoms'. As a clinical sign severity of conjunctival hyperaemia was evaluated. All adverse events were collected.

RESULTS

Three hundred and sixty patients were switched from monotherapy, 45 patients were naïve to treatment. A total of 139 patients were treated with fixed or non-fixed combinations prior to changing medication. In these patients preservative-free tafluprost was used either as a substitution for the fixed or non-fixed combination, as an add-on to the existing combination therapy or as one agent in a newly initiated treatment regimen. Preservative-free tafluprost provided an IOP decrease in most pre-treatment subgroups, with an overall reduction of IOP in all patients (N = 544) from 19.4 +/- 5.0 mmHg at baseline to 15.7 +/- 4.1 mmHg after 4 to 6 weeks and to 15.3 +/- 3.5 mmHg after 12 weeks. Both values were significantly lower than treated baseline IOP (p < 0.001). An IOP of <or=18 mmHg was achieved in 79.5% of eyes treated with the preservative-free formulation of tafluprost 12 weeks after changing medication. Both subjective symptoms and objective clinical signs improved after changing medication. Only a few adverse events occurred during the follow-up period.

CONCLUSIONS

Although this study was limited by its observational design, the results demonstrate that preservative-free tafluprost is an effective, well tolerated, and safe medication in a patient population with poor IOP control and/or tolerability issues with their medication prior used.

Analysis of cat oocyte activation methods for the generation of feline disease models by nuclear transfer

BACKGROUND

Somatic cell nuclear transfer in cats offers a useful tool for the generation of valuable research models. However, low birth rates after nuclear transfer hamper exploitation of the full potential of the technology. Poor embryo development after activation of the reconstructed oocytes seems to be responsible, at least in part, for the low efficiency. The objective of this study was to characterize the response of cat oocytes to various stimuli in order to fine-tune existing and possibly develop new activation methods for the generation of cat disease models by somatic cell nuclear transfer.

METHODS

First, changes in the intracellular free calcium concentration [Ca2+]i in the oocytes induced by a number of artificial stimuli were characterized. The stimuli included electroporation, ethanol, ionomycin, thimerosal, strontium-chloride and sodium (Na+)-free medium. The potential of the most promising treatments (with or without subsequent incubation in the presence of cycloheximide and cytochalasin B) to stimulate oocyte activation and support development of the resultant parthenogenetic embryos was then evaluated. Finally, the most effective methods were selected to activate oocytes reconstructed during nuclear transfer with fibroblasts from mucopolysaccharidosis I- and alpha-mannosidosis-affected cats.

RESULTS

All treatments were able to elicit a [Ca2+]i elevation in the ooplasm with various characteristics. Pronuclear formation and development up to the blastocyst stage was most efficiently triggered by electroporation (60.5 +/- 2.9 and 11.5 +/- 1.7%) and the combined thimerosal/DTT treatment (67.7 +/- 1.8 and 10.6 +/- 1.9%); incubation of the stimulated oocytes with cycloheximide and cytochalasin B had a positive effect on embryo development. When these two methods were used to activate oocytes reconstructed during nuclear transfer, up to 84.9% of the reconstructed oocytes cleaved. When the 2 to 4-cell embryos (a total of 220) were transferred into 19 recipient females, 4 animals became pregnant. All of the fetuses developed from oocytes activated by electroporation followed by cycloheximide and cytochalasin B incubation; no fetal development was detected as a result of thimerosal/DTT activation. Although heartbeats were detected in two of the cloned fetuses, no term development occurred.

CONCLUSION

Electroporation proved to be the most effective method for the activation of cat oocytes reconstructed by nuclear transfer. The combined thimerosal/DTT treatment followed by cycloheximide and cytochalasin B incubation triggered development effectively to the blastocyst stage; whether it is a viable option to stimulate term development of cloned cat embryos needs further investigations.