Lecithin vesicles for topical delivery of diclofenac.

Skin penetration of topically applied diclofenac is important for the treatment of rheumatic diseases and actinic keratoses. We have studied the permeation of diclofenac across human cadaver epidermis in-vitro from four lecithin vesicle formulations and a few marketed semi-solid preparations. The lecithin vesicle formulations were prepared by dissolving the lipid contents (lecithin and sodium cholate) in a 1:1 mixture of methanol-chloroform, evaporating the solvents under vacuum, and hydrating the lipid layer with the drug solution in water or 10% ethanol. The vesicles were sonicated for 5 min to reduce the vesicle size and their size and Zeta potential were characterized. The cumulative amount and maximum flux of diclofenac was 69.7+/-40.3 micrograms and 4.77+/-3.16 micrograms/hcm(2) from lecithin vesicles containing sodium cholate and 10% ethanol, and is the highest of all formulations studied. The cumulative amount and mean maximum flux obtained from other formulations were in the range of 2.46+/-1.98-29.9+/-10.1 micrograms and 0.53+/-0.46-3.61+/-0.86 micrograms/hcm(2). Based on the results, lecithin vesicles of diclofenac appear to be advantageous for the topical delivery of diclofenac.     

Biotinylated GHK peptide incorporated collagenous matrix: A novel biomaterial for dermal wound healing in rats

Matrikines are small peptide fragments of extracellular matrix proteins that display potent tissue repair activities. Difficulties in achieving sustained delivery of bioactive concentration of matrikines in the affected area limits their therapeutic use. The present study evaluates the effects biotinylated matrikine peptide (bio-glycyl-histidyl-lysine) incorporated collagen membrane for dermal wound healing processes in rats. Biotinylated peptide incorporated collagen matrix (PIC) showed better healing when compared to wounds treated with collagen matrix [CF (collagen film)] and without collagen [CR (control)]. Binding studies indicate that biotinylated GHK (Bio-GHK) binds effectively to the collagen matrix and red blood cell (RBC) membrane when compared with t-butyloxycarbonyl substituted GHK (Boc-GHK). Wound contraction, increased cell proliferation, and high expression of antioxidant enzymes in PIC treated group indicate enhanced wound healing activity when compared to CF and CR groups. Interestingly Bio-GHK incorporated collagen increases the copper concentration by ninefold at the wound site indicating the wound healing property of Bio-GHK can also be linked with both copper localization and matrikine activities. These results demonstrate the possibility of using Bio-GHK incorporated collagen film as a therapeutic agent in the wound healing process.     

Molecular characterization and interviral relationships of a flexuous filamentous virus causing mosaic disease of sugarcane (Saccharum officinarum L.) in India

Summary.  A virus isolate causing mosaic disease of commercial sugarcane was purified to homogeneity. Electron microscopy revealed flexuous filamentous virus particles of ca 890 × 15 nm. The virus isolate reacted positively with heterologous antiserum to narcissus latent virus form UK, but failed to react with potyvirus group specific antiserum. N-terminal sequencing of the intact coat protein (CP) and the tryptic peptides indicated that the virus was probably a potyvirus but distinct from several reported potyviruses. Comparison of the 3′-terminal 1084 nucleotide sequence of the RNA genome of this virus revealed 93.6% sequence identity in the coat protein coding region with the recently described sugarcane streak mosaic virus (Pakistani isolate). The molecular weight of the coat protein (40 kDa) was higher than that deduced from the amino acid sequence (34 kDa). The apparent increase in size was shown to be due to glycosylation of the coat protein which has not been reported thus far in the family, Potyviridae. This is the first report on the molecular characterization of a virus causing mosaic disease of sugarcane in India and the results demonstrate that the virus is a strain of sugarcane streak mosaic virus, a member of the Tritimovirus genus of the Potyviridae. We have named it sugarcane streak mosaic virus – Andhra Pradesh isolate (SCSMV-AP). Received October 14, 1997 Accepted August 7, 1998     

Viscoless Manual Small Incision Cataract Surgery with Trabeculectomy

Purpose: To compare the efficacy of combined manual small incision cataract and glaucoma surgery with anterior chamber maintainer (ACM) alone versus that with intraoperative viscoelastics. Methods: Hospital electronic medical records of patients who underwent small incision cataract and trabeculectomy and intraocular lens implantation without Mitomycin-C from 2014 to 2016 were identified from the hospital operation theater database for this retrospective, hospital-based comparative study. All MSICS surgeries were performed by a single surgeon under peribulbar block. Data retrieved from all patients undergoing surgery with viscoelastic (group 2) or under AC maintainer without viscoelastic (group 1) included preoperative visual acuity, preoperative treated intraocular pressure, number of anti-glaucoma medications before surgery, total surgical time, intraoperative complications, postoperative best-corrected visual acuity and IOP at one week and one month, need for additional procedures, and corneal clarity. Differences in surgical time and postoperative course in both groups were compared. Results: Of 268 manual combined cataract and glaucoma surgeries done from 2014–2016, we identified 147 eyes of 130 age-matched patients, which included 51 PACG, 50 POAG, 12 NTG, and 24 PXG eyes with a mean age of 66 ±11.2 years and 64± 10.8 years in group 2 (n=74) and group 1 (n=73), respectively; p=0.9. The surgical time was significantly lower in group 1 (16±4.8 minutes compared to 44±14.6 minutes for group 2; p<0.001) with transient edema seen <1 week after surgery in 24 eyes of group 2 and seven eyes of group 1; p=0.02. The postoperative IOP at all postoperative visits dropped to >50% in both groups with 11 eyes (PXG n=6, PACG n=5) requiring medications for rise in intraocular pressure at a median time of 1.2 months (r=0.2–3 months). The final visual acuity improved >4 snellen lines in all cases with two patients with advanced damage having 1 line improvement in Snellen acuity at final follow-up. Conclusion: The ACM can help completely avoid the use of viscoelastic during surgery, which can be an effective technique for MSICS with trabeculectomy in low resource stings. Training for such procedures should be incorporated into residency training programs.