Monitoring the Effect of Transdermal Drug Delivery Patches on the Skin Using Terahertz Sensing

Water content of the skin is an important parameter for controlling the penetration rate of chemicals through the skin barrier; therefore, for transdermal patches designed for drug delivery to be successful, the effects of the patches on the water content of the skin must be understood. Terahertz (THz) spectroscopy is a technique which is being increasingly investigated for biomedical applications due to its high sensitivity to water content and non-ionizing nature. In this study, we used THz measurements of the skin (in vivo) to observe the effect of partially and fully occlusive skin patches on the THz response of the skin after the patches had been applied for 24 h. We were able to observe an increase in the water content of the skin following the application of the patches and to identify that the skin remained hyper-hydrated for four hours after the removal of the fully occlusive patches. Herein, we show that THz spectroscopy has potential for increasing the understanding of how transdermal patches affect the skin, how long the skin takes to recover following patch removal, and what implications these factors might have for how transdermal drug patches are designed and used.

Immunogenicity and safety of inactivated Influenza Split-Virion vaccine administered via a transdermal micro needle system

The purpose of the study was to evaluate the immunogenicity and safety of an inactivated influenza split virion vaccine administered via a transdermal microneedle system. In this Phase 1, single-center, randomized, controlled study, 90 subjects aged 18 to 40 years received influenza vaccine (strains (A/H1N1, A/H3N2, and B) either via a transdermal microneedle system (“patch”; 10 µg) for 5 or 15 minutes or by Intramuscular (IM) injection (15g). Influenza antibody titers were measured by the hemagglutinin inhibition method and compared to EMEA guidelines for influenza vaccines (seroconversion rate, mean increase in hemagglutinin inhibition titer, and percentage of seroprotected subjects). Safety was assessed through local and systemic adverse events, and specific application site events in the transdermal groups. At Day 21, the EMEA criteria were met in all treatment groups for all three influenza strains. The immunogenicity response was similar between all three groups and increased antibody levels persisted to Month 6. The transdermal microneedle system was generally well tolerated, although pinpoint red spots, edema, and erythema were noted after patch removal in most subjects. Influenza vaccination administered via a novel transdermal microneedle system was generally well tolerated and provided similar antibody response using a lower dose than IM injection.

Conservative Surgical Management of Late Carotid Patch Infection in a Patient with Subsequent Stenting for Restenosis

Carotid patch infection is a rare but dreaded complication after endarterectomy. About 160 cases can be found in literature, but presentation in a patient with post-endarterectomy stenting has not been reported. Most frequent clinical manifestations include the occurrence of a sinus, a pseudoaneurysm, or neck swelling, but in severe cases it may present anastomosis dehiscence with hematoma or hemorrhage. Usually, patch removal and reconstruction is recommended, but there is not a standard protocol for management. Conservative surgical management with patch preservation has only been reported in a minority of cases. We report a patient with a history of carotid endarterectomy and subsequent carotid stenting 21 months later because of >80% restenosis. He presented a sinus in the scar 81 months after the former intervention. The patient underwent surgery, and during the procedure, a detachment of a small segment of the Dacron patch from the surrounding tissue was found. The sinus tract was resected, and after verifying the integrity of the patch, it was irrigated with rifampicin and preserved in situ. S. epidermidis was isolated from tissue cultures. Twenty-four months later, the patient remains asymptomatic and duplex ultrasound shows no signs of infection. Conservative surgical approach can be a valid option for treatment and may be considered in selected patients with limited infection.

Fentanyl Plasma Concentrations after Application of a Transdermal Patch in Three Different Locations to Refine Postoperative Pain Management in Rabbits

Transdermal patches allow a noninvasive and “stress free” analgesia in rabbits. As fentanyl uptake is dependent on exogenous and endogenous factors of the area where the patch is applied, this study investigated three different locations (neck, inner and outer surfaces of the ear) for fentanyl patch application to provide adequate and reliable fentanyl plasma concentrations above those previously shown to be analgesic. Fentanyl plasma concentration was measured at different time points (3, 6, 9, 12, 18, 24, 36, 48, 72, 96, 120 h) and rabbits were assessed for their general conditions and treatment-related side effects. Practicability of the proposed methods was evaluated. Following patch application on the neck, fentanyl plasma concentrations equal to or above the analgesic value were measured in all rabbits between 6 and 72 h. Comparable concentrations were reached between 9 and 48 h in all animals for the outer ear surface. However, for the inner ear surface, analgesic concentrations were not reached, even if practicability was considered the best for this location. Preparation of the neck skin was judged as the most cumbersome due to the clipping of the dense fur and patch removal resulted in erythema. In summary, the application of the fentanyl patch on the neck and outer ear surface allowed the reach of reliable plasma concentrations above the analgesic threshold in rabbits. When applied on the neck, fentanyl patches provided the longest duration of analgesic plasma concentrations, whereas patch application and removal were easier on the outer ear surface.

Full time occlusion VS part time occlusion in treatment of monocular amblyopia

Objective: To compare improvement in Best Corrected Visual Acuity (BCVA) by Full Time Occlusion (FTO) or Part Time Occlusion (PTO) technique in children with monocular amblyopia. Methods: This randomized control trial was conducted at Combined Military Hospital, Gujranwala from April 2018 to June 2019. A total of 52 children, diagnosed with non-pathological ametropic amblyopia were randomly divided in two groups. Both underwent cycloplegic refraction and assessment of BCVA. Group A underwent FTO for eight weeks with patch removal only during sleep. Group B underwent PTO for eight weeks with patching done for six hours a day, out of which 1-2 hours were utilized in near work. Final BCVA was checked at eight weeks, and compared between two groups. Results: Mean age of study population was 11.06±3.30 years. Mean BCVA before amblyopia treatment was 0.70±0.20 logMAR, and mean BCVA after eight weeks of amblyopia treatment in both groups was 0.29±0.18 logMAR. Difference in BCVA between both groups was statistically significant (p= 0.023). Mean improvement in lines on Snellen’s Visual acuity chart was 1.92±1.35 lines. In our study, 92% of children in FTO group and 66.6% of children in PTO group achieved BCVA of 6/12 or better. Conclusions: Full time occlusion in children with monocular amblyopia results in greater improvement in BCVA as compared to part time occlusion of six hours per day. doi: https://doi.org/10.12669/pjms.35.6.1287 How to cite this:Mehboob MA, Muhammad S, Farooq MA. Full time occlusion VS part time occlusion in treatment of monocular amblyopia. Pak J Med Sci. 2019;35(6):1647-1651. doi: https://doi.org/10.12669/pjms.35.6.1287 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Japanese Rose (Rosa rugosa): its invasion and colonisation of the Sefton Coast, north Merseyside, UK

A spiny shrub native to north-west Pacific coasts, Rosa rugosa Thunb. (Japanese Rose) was introduced into Britain in the 19th century as a garden plant. It has since become a well-established and widespread naturalised alien, especially on sand-dunes, shingle beaches and other dry coastal habitats. The plant is also considered invasive on coasts of many other countries in Northwest Europe. Mounting concern about its recent spread on the internationally important sand-dune system of the Sefton Coast, north Merseyside, led to a volunteer survey being organised in 2014, involving 47 participants. They searched most of the 27 km-long coastal zone, recording almost 500 patches with a total area of nearly 6 ha. R. rugosa occurred especially on younger calcareous dunes (soil pH 5.6 – 8.2) near the sea and close to roads and human habitation. Few patches were found on older, more acidic duneland, or on a 5 km erosion front around Formby Point. This pattern of occurrence accords with that reported elsewhere for R. rugosa, indicating that the sea is implicated in the dispersion of propagules and that the species also establishes from anthropogenic sources, including ornamental plantings. It is concluded that the plant is a threat to dune habitats and species on the Sefton Coast. Control measures are discussed and the early stages of patch removal are described.

Efficacy of EGF and Gelatin Sponge for Traumatic Tympanic Membrane Perforations: A Randomized Controlled Study

Objective To compare the outcomes of epidermal growth factor (EGF) and gelatin sponge patch treatments for traumatic tympanic membrane perforations. Study Design Prospective, randomized, controlled. Setting University-affiliated teaching hospital. Subjects and Methods In total, 141 perforations encompassing >50% of the eardrum were randomly divided into 3 groups: EGF (n = 47), gelatin sponge patch (n = 47), and observation (n = 47). The edges of the perforations were not approximated. The closure rate, mean closure time, and infection rate were evaluated at 6 months and the related factors analyzed. Results A total of 135 perforations were analyzed. At 6 months, the closure rates were 97.8%, 86.7%, and 82.2% in the EGF, gelatin sponge patch, and spontaneous healing groups, respectively ( P = .054). The mean ± SD closure time was 11.12 ± 4.60, 13.67 ± 5.37, and 25.65 ± 13.32 days in the EGF, gelatin sponge patch, and spontaneous healing groups, respectively ( P < .001). In addition, the presence of infection was not significantly associated with rate of closure in any group. Conclusions As compared with spontaneous healing, daily application of EGF and gelatin sponge patching reduced the closure time of traumatic tympanic membrane perforations. EGF treatment had a higher closure rate and shorter closure time but resulted in otorrhea. By contrast, gelatin sponge patches did not improve the closure rate or cause otorrhea but required repeated patch removal and reapplication. Thus, the appropriate treatment should be selected according to patient need.