Topical antibacterial agents in dermatology

Topical antibacterials are being widely used for the treatment or prevention of superficial bacterial infections. Emergence of drug resistant mutant strains of microorganisms and development of irritant and allergic contact dermatitis is a common problem with many of the topical antibacterials. Topical antibacterials are being reviewed with special emphasis on their spectrum of activity, resistance patterns, contact sensitivity potential and clinical uses. Factors which help the physician to choose a particular antibacterial for the specific indication in order to have the maximum efficacy and minimum adverse effects are discussed.     

Squamous cell carcinoma in long-standing untreated lichen sclerosus et atrophicus of the penis

Lichen sclerosus et atrophicus is an uncommon disease of skin and genital mucosa in both sexes. Involvement of the male genital mucosa is usually complicated by recurrent balanoposthitis, ulceration, phimosis, and meatal stenosis. The development of a squamous cell carcinoma is extremely rare in genital lichen sclerosus et atrophicus in males as compared with females. We report a 70-year-old male with a squamous cell carcinoma of the glans superimposed on long-standing lichen sclerosus et atrophicus of glans and prepuce. The patient in addition had a basal cell carcinoma on his face. Awareness of this rare complication of lichen sclerosus et atrophicus in males is emphasized.     

Prevalence and risk of colorectal neoplasia in consumers of alcohol in a screening population

BACKGROUND AND AIMS: Although studies suggest a positive association between alcohol consumption and risk for colorectal neoplasia, the impact on screening has not been fully examined. It is also unclear whether all types of alcohol are associated with an increased risk. We performed a cross-sectional study to examine the impact of regular alcohol consumption on the detection of significant colorectal neoplasia in a screening population. METHODS: Data collected for 2,291 patients presenting for screening colonoscopy: known risk factors for colorectal neoplasia and alcohol drinking pattern. Our outcome was the endoscopic detection of significant colorectal neoplasia, which included adenocarcinoma, high-grade dysplasia, villous tissue, adenomas 1 cm or greater and multiple (>2) adenomas of any size. RESULTS: When compared to abstainers, we found an increased risk for significant neoplasia in those patients who consumed more than eight drinks of spirits alcohol (26.3%; OR = 2.53; 95% CI = 1.10-4.28; p < 0.01) and those who drank more than eight servings of beer per week (21.7%; OR = 2.43; 95% CI = 1.11-5.32; p= 0.02). Consuming one to eight glasses of wine per week was associated with a decreased risk for significant neoplasia (OR = 0.55; 95% CI = 0.34-0.87; p < 0.01). CONCLUSIONS: While there was a more than twofold increased risk of significant colorectal neoplasia in people who drink spirits and beer, people who drank wine had a lower risk. In our sample, people who drank more than eight servings of beer or spirits per week had at least a one in five chance of having significant colorectal neoplasia detected by screening colonoscopy.     

Nanoparticle‐stabilized microbubbles for multimodal imaging and drug delivery

Microbubbles (MBs) are routinely used as contrast agents for ultrasound imaging. The use of ultrasound in combination with MBs has also attracted attention as a method to enhance drug delivery. We have developed a technology platform incorporating multiple functionalities, including imaging and therapy in a single system consisting of MBs stabilized by polyethylene glycol (PEG)‐coated polymeric nanoparticles (NPs). The NPs, containing lipophilic drugs and/or contrast agents, are composed of the widely used poly(butyl cyanoacrylate) (PBCA) polymer and prepared in a single step. MBs stabilized by these NPs are subsequently prepared by self‐assembly of NPs at the MB air–liquid interface. Here we show that these MBs can act as contrast agents for conventional ultrasound imaging. Successful encapsulation of iron oxide NPs inside the PBCA NPs is demonstrated, potentially enabling the NP–MBs to be used as magnetic resonance imaging (MRI) and/or molecular ultrasound imaging contrast agents. By precise tuning of the applied ultrasound pulse, the MBs burst and the NPs constituting the shell are released. This could result in increased local deposit of NPs into target tissue, providing improved therapy and imaging contrast compared with freely distributed NPs. Copyright © 2015 John Wiley & Sons, Ltd.     

Development of metoprolol tartrate extended-release matrix tablet formulations for regulatory policy consideration

This research study was designed to develop model extended-release (ER) matrix tablet formulations for metoprolol tartrate (100 mg) sufficiently sensitive to manufacturing variables and to serve as the scientific basis for regulatory policy development on scale-up and post approval changes for modified-release dosage forms (SUPAC-MR). Several grades and levels of hydroxypropyl methylcellulose (Methocel K4M, K15M, K100M and K100LV), fillers and binders were studied. Three granulation processes were evaluated; direct compression, fluid-bed or high-shear granulation. Lubrication was performed in a V-blender and tablets were compressed on an instrumented rotary tablet press. Direct compression formulations exhibited poor flow, picking and sticking problems during tableting. High-shear granulation resulted in the formation of hard granules that were difficult to mill but yielded good tablets. Fluid-bed granulations were made using various binders and appeared to be satisfactory in terms of flow and tableting performance. In vitro drug release testing was performed in pH 6.8 phosphate buffer using USP apparatus 2 (paddle) at 50 rpm. At a fixed polymer level, drug release from the higher viscosity grades (K100M) was slower as compared to the lower viscosity grades (K100LV). In addition, release from K100LV was found to be more sensitive to polymer level changes. Increase in polymer level from 10 to 40% and/or filler change from lactose to dicalcium phosphate resulted in about 25–30% decrease in the amount of metoprolol release after 12 h. The results of this study led to the choice of Methocel K100LV as the hydrophilic matrix polymer and fluid-bed granulation as the process of choice for further evaluation of critical and non-critical formulation and processing variables.     

Human bite-induced penile ulceration: report of a case and review of literature

Human bite on genitalia is a rare cause of penile ulceration, but is increasingly being reported, probably due to the increasing frequency of orogenital sex. The great morbidity associated with it brings it under the category of high-risk bite wounds, similar to those on hands, feet and joints. We report a case and review the literature on human bite-induced penile ulceration.