Protein-based microneedles for biomedical applications: A systematic review.

Microneedles are minimally-invasive devices with the unique capability of bypassing physiological barriers. Hence, they are widely used for different applications from drug/vaccine delivery to diagnosis and cosmetic fields. Recently, natural biopolymers (particularly carbohydrates and proteins) have garnered attention as safe and biocompatible materials with tailorable features for microneedle construction. Several review articles have dealt with carbohydrate-based microneedles. This review aims to highlight the less-noticed role of proteins through a systematic search strategy based on the PRISMA guideline from international databases of PubMed, Science Direct, Scopus, and Google Scholar. Original English articles with the keyword "microneedle(s)" in their titles along with at least one of the keywords "biopolymers, silk, gelatin, collagen, zein, keratin, fish-scale, mussel, and suckerin" were collected and those in which the proteins undertook a structural role were screened. Then, we focused on the structures and applications of protein-based microneedles. Also, the unique features of some protein biopolymers that make them ideal for microneedle construction (e.g., excellent mechanical strength, self-adhesion, and self-assembly), as well as the challenges associated with them were reviewed. Altogether, the proteins identified so far seem not only promising for the fabrication of "better" microneedles in the future but also inspiring for designing biomimetic structural biopolymers with ideal characteristics.

Development and evaluation of a novel methotrexate-loaded electrospun patch to alleviate psoriasis plaques.

OBJECTIVE: To achieve an effective topical formulation of Methotrexate (MTX) as a first-line treatment of psoriasis, we formulated three MTX-loaded electrospun nanofibrous patches composed of polycaprolactone (PCL), Eudragit L100, and a mixture of them. SIGNIFICANCE: Topical delivery of MTX provides an appropriate therapeutic performance while circumventing the life-threatening side effects of systemic administration. METHODS: Three MTX-loaded electrospun nanofibrous patches were prepared and characterized in terms of size and morphology (using SEM), thermal behavior (by TGA and DSC), and crystalline structure (using XRD). Furthermore, the wettability and mechanical strength of samples were investigated through water contact angle and tensile strength tests. Also, the encapsulation efficiency of MTX was calculated. Subsequently, in vitro drug release profile of each formulation was obtained and different kinetic models were fitted to achieve the best-matched model. Accordingly, the ex vivo skin permeation of MTX was studied for the optimum formulation. RESULTS: All samples showed appropriate morphology, thermal behavior, and encapsulation efficiency. Also, XRD results showed that MTX is dispersed within the polymeric matrices in the amorphous state (with no crystalline region). Release studies demonstrated that MTX-loaded Eudragit L100-PCL formulation outperformed in terms of mechanical behavior and in vitro drug release. This formulation also exhibited better skin permeation. CONCLUSION: The obtained controlled-release MTX-loaded electrospun patches seem promising to provide a long-acting topical treatment of psoriatic plaques with minimized systemic side effects.

Irrational antibiotic prescribing: a local issue or global concern?

Resistance to antibiotics is a major public-health concern and antibiotic use is being ever more recognized as the main discriminatory pressure driving this resistance. The aim was to assess the outpatient usage of antibiotics in teaching hospitals in various parts of capital city of Iran, Tehran and its association with resistance. 600 outpatient antibiotic prescriptions between December 2011 and May 2012 were reviewed in our teaching hospitals. All prescriptions were scrutinized in order to evaluate the antibiotic prescribing. The medical doctors from all grades were asked to note the chief complaints and the most possible diagnosis on each prescription. Clinical data, patient demographic and ultimately the total quantities of antibiotics were recorded. Our data was then compared against the major antibiotic guidelines and similar studies in other countries. The most common prescribed antibiotics are Penicillins (Penicillin, Co-Amoxiclav and Amoxicillin) (40 %), Cephalosporins (Cefixime, Cephalexin and Ceftriaxone) (24.5 %) and Macrolides (particularly Azithromycin) (15.3 %). In total, 18.2 % of cases were combinational antibacterial therapies (≥ 2). The most common diagnosis was upper respiratory tract infections as common cold (29.2 %) and sore throat (11.8 %). Directions (instructions for use) of 58 % of selected antibiotics were acceptable. Parenteral administration remains the common route of administration with 22 % of all reviewed prescriptions. Based on Cochrane reviews the antibiotic prescribing was unjustified in 42.7 % of the cases. The prescribing habit, correct diagnosis and the use of antibiotics need instant consideration. These data can provide useful information for assessing public-health policy that aims to reduce the antibiotic use and resistance levels.