Cellular uptake and anti-tumor activity of gemcitabine conjugated with new amphiphilic cell penetrating peptides

Gemcitabine (Gem) is used as a single agent or in combination with other anticancer agents to treat many types of solid tumors. However, it has many limitations such as a short plasma half-life, dose-limiting toxicities and drug resistance. Cell-penetrating peptides (CPPs) are short peptides which may deliver a large variety of cargo molecules into the cancerous cells. The current study was designed to evaluate the antiproliferative activity of gemcitabine chemically conjugated to CPPs. The peptides were synthesized using solid phase synthesis procedure. The uptake efficiency of CPPs into cells was examined by flow cytometry and fluorescent microscopy. The synthesized peptides were chemically conjugated to Gem and the in vitro cytotoxicity of conjugates was tested by MTT assay on A594 cell line. According to the obtained results, cellular uptake was increased with increasing the concentration of CPPs. On the other hand the coupling of Gem with peptides containing block sequence of arginine (R5W3R4) and some alternating sequences (i.e. [RW]6 and [RW]3) exhibited improved antitumor activity of the drug. The findings in this study support the advantages of using cell-penetrating peptides for improving intracellular delivery of Gem into tumor as well as its activity.

Job demand-control and job stress at work: A cross-sectional study among prison staff

INTRODUCTION

Job stress can impose significant costs to the workplaces and organizations due to some issues such as absenteeism, less productivity, and medical costs. Job overload and lack of decision latitude can lead to job stress. The current study aimed to investigate the job demands and control as predictor of job stress and its relationship, with some of the demographic characteristics of Iranian prison staff.

MATERIALS AND METHODS

This study was performed on 171 male employees working in four prisons located in Ilam, Iran. The sampling method was census and all four prisons' staff were selected to respond the Job Content Questionnaires. Finally, the data were analyzed using t-test or independent samples test as well as SPSS 20.

RESULTS

The highest amount of job demand (mean = 21.28) and the lowest amount of job control on average (9.76) were reported by those staff working in Darehshahr prison. There was also a significant relationship between job post and job control among the prison staff (β = -0.375, P = 0.001).

CONCLUSION

The level of job stress reported by prison staff was high in this study mainly caused by high job demand and low job control, especially in Darehshahr prison staff.

Crystal-liquid Fugacity Ratio as a Surrogate Parameter for Intestinal Permeability

BACKGROUND

We assessed the feasibility of using crystal-liquid fugacity ratio (CLFR) as an alternative parameter for intestinal permeability in the biopharmaceutical classification (BCS) of passively absorbed drugs.

METHODS

Dose number, fraction of dose absorbed, intestinal permeability, and intrinsic dissolution rate were used as the input parameters. CLFR was determined using thermodynamic parameters i.e., melting point, molar fusion enthalpy, and entropy of drug molecules obtained using differential scanning calorimetry.

RESULTS

The CLFR values were in the range of 0.06-41.76 mole percent. There was a close relationship between CLFR and in vivo intestinal permeability (r > 0.8). CLFR values of greater than 2 mole percent corresponded to complete intestinal absorption. Applying CLFR versus dose number or intrinsic dissolution rate, more than 92% of tested drugs were correctly classified with respect to the reported classification system on the basis of human intestinal permeability and solubility.

CONCLUSION

This investigation revealed that the CLFR might be an appropriate parameter for quantitative biopharmaceutical classification. This could be attributed to the fact that CLFR could be a measure of solubility of compounds in lipid bilayer which was found in this study to be directly proportional to the intestinal permeability of compounds. This classification enables researchers to define characteristics for intestinal absorption of all four BCS drug classes using suitable cutoff points for both intrinsic dissolution rate and crystal-liquid fugacity ratio. Therefore, it may be used as a surrogate for permeability studies. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.

The effects of Arnebia euchroma ointment on second-degree burn wounds: a randomized clinical trial

ETHNOBOTANICAL RELEVANCE

Burn injuries can cause detrimental long-term consequences and call for immediate management. Avicenna's Canon of Medicine, describing the use of Abu-Khalsa (Arnebia euchroma) (AE) as being effective for burn healing. The purpose of this study was to evaluate the healing effects of AE ointment (AEO) on patients with a second-degree burn wound and compare its results with silver sulfadiazine cream (SSD).

MATERIALS AND METHODS

In this prospective, single-blind clinical trial, 45 patients with similar types of second-degree burns at two different sites of the body were randomly assigned to the two treatment groups. One burn wound site of the patient was treated with SSD and another similar burn wound site with AEO once a day until complete healing was achieved. Wound size and percentage of wound healing were evaluated at 15 days. Satisfaction, clinical adverse events such as pain, burning, warming, erythema, edema, infection, inflammation, and general wound area were assessed on a visual analogue scales, and 6-point scales.

RESULTS

The healing time was significantly shorter in the site treated with AEO than SSD (13.9±5.3 vs. 17.5±6.9 days, respectively). The severity of pain and burning were reduced in the AEO site compared with SSD site at the time of dressing change, while the warming score was significantly higher in the AEO wound area. Side-effects were lower in the site treated with AEO.

CONCLUSION

In this clinical study, we demonstrated that AEO has benefits over SSD in the treatment of second-degree burn wounds and wound healing and is a viable medication for the management of second-degree burns.

The effect of Terminalia chebula extract vs. silver sulfadiazine on burn wounds in rats

BACKGROUND

The aim of this study was to evaluate the efficacy of ethanol extract of Terminalia chebula in the treatment of hot water-induced burn wounds and to compare the results with silver sulfadiazine (SSD) in rats.

METHODS

Five groups of ten rats were burned with hot water. Animals were administrated with topical cream at control, normal saline, 5%, 10% T. chebula extracts and standard SSD creams. Several parameters were assessed, including wound area, visual inspection of wound, bacteriology assessment, percentage of wound contraction and histopathological examination.

RESULTS

The average area of wound on 10th day was 11.2 ± 3.3, 11 ± 3.2, 8.5 ± 2.3, 9.5 ± 4.2 and 5.1 ± 2.2 cm(2) for SSD1%, base cream, normal saline, herbal extract 5% and 10%, respectively. T. chebula 10% cream exhibited lower wound size than SSD1% and control groups at 10th day post burn injury. On day 15, the percentage of wound contraction in T. chebula was 5% and 10% more than 18% and 53% in comparison to SSD1% group, respectively. Histopathological results exhibited well-formed horizontally oriented collagen fibers for appropriate tension. Strength of scar on burned tissue was better in T. chebula 5% and 10% as compared with control and SSD groups.

CONCLUSIONS

The results of this study showed that T. chebula extract was capable of accelerating wound healing in rats by wound contraction, and had beneficial effects more than SSD 1% cream in the management of burn injury.

The Effect of Tween 20, 60, and 80 on Dissolution Behavior of Sprionolactone in Solid Dispersions Prepared by PEG 6000

PURPOSE

Solid dispersions have been efficient in improving the dissolution rate and bioavailability of hydrophobic drugs. The aim of the present study was enhancement of the dissolution profile of Spironolactone using solid dispersion.

METHODS

Spironolactone solid dispersions (1:1, 1:2 and 2:1 drug: carrier weight ratio) were prepared by polyethylene glycol (PEG) 6000 as a carrier by hot melt method. The influence of several amounts of Tween 20, 60, and 80 were also studied. The dissolution profile was evaluated by USP Apparatus II.

RESULTS

The results showed that solid dispersions were efficacious to enhance the dissolution rate of Spironolactone in water; and the procedure indicated that there was an increase in dissolution rate for solid dispersions containing the surfactant Tweens. The solid dispersions were evaluated using Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) and Differential Scanning Calorimetry (DSC) studies; and the results showed no complex formation or change in crystal shape of drug.

CONCLUSION

It is concluded that solid dispersion technique can be successfully used for improvement of dissolution of Spironolactone.

The Healing Effect of Arnebia Euchroma Ointment versus Silver Sulfadiazine on Burn Wounds in Rat

BACKGROUND

Burn is still a majordevastating condition in emergency medicine departments among both genders and all age groups in all developed and developing countries, leading to physical, psychological scars and economical burden. The present study aimed to determine the healing effect of topical treatment with Arnebia euchroma on second-degree burn wound in rats.

METHODS

Fifty rats were divided into 4 equal groups receiving the ointment base, normal saline (NS), standard 1% silver sulfadiazine (SSD), and 5% and 10% Arnebia euchroma ointments (AEO). The mean of burn area, percentage of wound contraction, histopathological and bacteriological assessments in the injured area were dtermined during the study.

RESULTS

Average area of wound on the 10(th) day was 10.2±2.3, 8.4±2.6, 12.4±2.5, 5.9±2.2 and 5.7±2 cm(2) for ointment base, NS, 1% SSD, and 5% and 10% AEO, respectively. Wound size was significantly lower in 10% AEO than 1% SSD and control groups on the 10(th) day post-burn injury. On day 11, the percentage of wound contraction in 5% and 10% AEO was 53.9%±14.7% and 55.9±10.5% which was more than 1% SSD (15.3±10.8%). The collagen fibers were well formed and horizontally-oriented in 5% and 10% AEO groups when compared with other groups.

CONCLUSION

Arnebia euchroma ointment was an effective treatment for healing of burn wounds in comparison with SSD and can be regarded as an alternative topical treatment for burn wounds.

Effect of Malva sylvestris cream on burn injury and wounds in rats

OBJECTIVES

Burn injury is one of the most health-threatening problems in the world. Malva sylvestris (M. sylvestris) flowers have a high mucilage content and are used as a remedy for cut wound and dermal infected wounds in Iranian folklore Medicine. The purpose of this study was to investigate the effect of M. sylvestris cream on the second degree burn injury in rats.

MATERIALS AND METHODS

Five groups of 10 rats per group were burned with hot metal plate. Animals were administrated divided as control, normal saline, standard silver sulfadiazine 1% (SSD), 5% M. sylvestris, and 10% M. sylvestris into separate groups. Wound area, percentage of wound contraction, and histological and bacteriological assessments were evaluated.

RESULTS

Wound sizes were not significantly different among groups on 1(st) and 3(rd) days after burn injury, while they were significantly different among groups after 7(th) day post-burn injury. The average areas of wounds on the 15(th) day were 7.5±2.9, 6.7±2, 10.5±1.6, 4.7±2, and 4.5±2 cm(2) for base cream, normal saline, SSD, 5% M. sylvestris, and 10% M. sylvestris, respectively. The results of histology exhibited well-formed horizontally-oriented collagen fibers in MS topical treatment groups. Microorganisms existed in the SSD group were most probably Staphilococcus epidermitis and for NS group were staphylococcus saprophiteccus.

CONCLUSION

M. sylvestris cream improved histological changes of tissue components in the process of healing when compared with SSD cream. Therefore, it can be used as a topical treatment agent for burn wound.

Transdermal absorption enhancing effect of the essential oil of Rosmarinus officinalis on percutaneous absorption of Na diclofenac from topical gel

CONTEXT

Rosemary essential oil has been used topically for several purposes (analgesic, anti acne, and anti-inflammatory) in Iranian traditional medicine.

OBJECTIVES

This investigation aimed to study the effect of essential oil of Rosmarinus officinalis L. (Lamiaceae) on the transdermal absorption of Na diclofenac from topical gel.

MATERIAL AND METHODS

Diclofenac sodium topical gel was prepared with HPMC K4M and Carbopol 934P as a gelling agent, and several vehicles. The most stable gel was chosen and enhancing effects of the essential oil with different concentrations (0.1, 0.5, and 1.0% w/w) on the permeation of diclofenac were evaluated. The anti-nociceptive effect of preparations was evaluated based on the formalin and tail flick tests in mice.

RESULTS

The major constituents of the essential oil were 1,8-cineol (15.96%), α-pinene (13.38%), camphor (7.87%), bornyl acetate (6.54%), verbenone (5.82%), borneol (5.23%), camphene (4.96%), and (E)-caryophyllene (3.8%). Topical diclofenac containing 0.5% essential oil showed more analgesic effect after 25, 30, and 35 min (p < 0.001) than the reference drug in the tail flick test. The analgesic effect of preparation containing 1% essential oil was more than reference gel after 15 min (p < 0.05). This difference was observed after 20, 25, 30, 35, and 40 min (p < 0.001) too. Rosemary essential oil 1% promoted analgesic effect of drug in comparison with diclofenac gel in the formalin early phase (p < 0.05). The enhancing effect of rosemary was observed in 0.5 and 1% concentration (p < 0.05 and p < 0.001, respectively) in the late phase.

CONCLUSION

This study proved the enhancing effect of 0.5 and 1% of rosemary essential oil on diclofenac percutaneous absorption.

Imidazolium-based ionic liquids as modulators of corrosion inhibition of SDS on mild steel in hydrochloric acid solutions: experimental and theoretical studies

Surface interaction and corrosion processes of imidazolium-based ionic liquids and their mixtures with SDS on a mild steel surface.

Formulation and characterization of cetylpyridinium chloride bioadhesive tablets

PURPOSE

Bioadhesive polymers play an important role in biomedical and drug delivery applications. The aim of this study is to develop a sustained- release tablet for local application of Cetylpyridinium Chloride (CPC). This delivery system would supply the drug at an effective level for a long period of time, and thereby overcome the problem of the short retention time of CPC and could be used for buccal delivery as a topical anti-infective agent.

METHODS

CPC bioadhesive tablets were directly prepared using 7 mm flat-faced punches on a hydraulic press. The materials for each tablet were weighted, introduced into the die and compacted at constant compression pressure. The dissolution tests were performed to the rotation paddle method and the bioadhesive strength of the tablets were measured.

RESULTS

The results showed that as the concentration of polymer increased, the drug release rate was decreased. Also the type and ratio of polymers altered the release kinetic of Cetylpyridinium Chloride from investigated tablets. The bioadhesion strength increased with increasing the concentration of polymer and maximum bioadhesion strength was observed with HPMC K100M.

CONCLUSION

The selected formulation of CPC bioadhesive tablet can be used as a suitable preparation for continuous release of CPC with appropriate bioadhesion strength.

Job stress among Iranian prison employees

BACKGROUND

Exposure to job stress causes deleterious effects on physical and mental health of employees and productivity of organizations.

OBJECTIVE

To study work-related stressors among employees of prisons of Ilam, western Iran.

METHODS

In a cross-sectional study conducted from July to October 2013, 177 employees of Ilam prisons and security-corrective measures organization were enrolled in this study. The UK Health and Safety Executive Organization 35-item questionnaire for assessment of occupational stress was used to determine job stress among the studied employees.

RESULTS

Job stress was highest among employees of "correction and rehabilitation center" of Ilam province followed by "Dalab vocational training center." There was no significant relationship between occupational stress and age, work experience, level of education, marital status, sex of employees, and obesity.

CONCLUSION

Employees of prisons, for their nature of job and work environment, are exposed to high level of occupational stress.