Is Proflavine Exposure Associated with Disease Progression in Women with Cervical Dysplasia? A Brief Report.

Proflavine is an acridine dye used with high-resolution microendoscopy for in vivo diagnostic evaluation of cervical epithelial cells. However, there are concerns that even short-term exposure of cervical tissue to dilute proflavine may increase cervical cancer risk. We performed a retrospective analysis of women referred for colposcopy to Barretos Cancer Hospital comparing the risk of cervical disease progression in those whose cervical tissue was (n = 232) or was not exposed (n = 160) to proflavine. Patients in both groups underwent treatment and follow-up based on histopathologic results and per the local standards of care. Progression of disease was evaluated by comparing histopathology from the initial visit to the worst subsequent histopathology result from all follow-up visits. Mean duration of follow-up was 18.7 and 20.1 months for the proflavine-exposed and controls groups, respectively. There were no significant differences in disease progression from normal/CIN1 to CIN2/3 or from any initial diagnosis to invasive cancer between the proflavine exposed and control groups overall. Risks of cervical dysplasia progression observed in this study are in agreement with those of the natural history of cervical cancer. Our results suggest that cervical exposure to dilute proflavine does not increase the risk of cervical precancer and cancer.

Prospective Evaluation of Multimodal Optical Imaging with Automated Image Analysis to Detect Oral Neoplasia In Vivo.

The 5-year survival rate for patients with oral cancer remains low, in part because diagnosis often occurs at a late stage. Early and accurate identification of oral high-grade dysplasia and cancer can help improve patient outcomes. Multimodal optical imaging is an adjunctive diagnostic technique in which autofluorescence imaging is used to identify high-risk regions within the oral cavity, followed by high-resolution microendoscopy to confirm or rule out the presence of neoplasia. Multimodal optical images were obtained from 206 sites in 100 patients. Histologic diagnosis, either from a punch biopsy or an excised surgical specimen, was used as the gold standard for all sites. Histopathologic diagnoses of moderate dysplasia or worse were considered neoplastic. Images from 92 sites in the first 30 patients were used as a training set to develop automated image analysis methods for identification of neoplasia. Diagnostic performance was evaluated prospectively using images from 114 sites in the remaining 70 patients as a test set. In the training set, multimodal optical imaging with automated image analysis correctly classified 95% of nonneoplastic sites and 94% of neoplastic sites. Among the 56 sites in the test set that were biopsied, multimodal optical imaging correctly classified 100% of nonneoplastic sites and 85% of neoplastic sites. Among the 58 sites in the test set that corresponded to a surgical specimen, multimodal imaging correctly classified 100% of nonneoplastic sites and 61% of neoplastic sites. These findings support the potential of multimodal optical imaging to aid in the early detection of oral cancer. Cancer Prev Res; 10(10); 563-70. ©2017 AACR.

Determination of proflavine in rat whole blood without sample pretreatment by laser desorption postionization mass spectrometry.

A novel pretreatment-free method involving laser desorption postionization (LDPI) coupled with time-of-flight mass spectrometry (MS) was developed for the monitoring of proflavine level in rat whole blood. It comprises a protocol for dosing via intravenous administration and collection of whole blood, followed by direct LDPI-MS analysis without any sample pretreatment. An intense ion signal at m/z 209 was observed from whole blood without any interference signals, except some background signals below m/z 100. The calibration curve was established with use of 9-phenylacridine as the internal standard for proflavine determination from the plotting of the peak ratios of proflavine to the internal standard, with a correlation coefficient (R 2) greater than 0.99. The limit of detection was estimated to be 0.48 pmol/mm2 and the quantification range was 0.5-16.5 µg/mL for proflavine. In addition, only a minimal matrix effect was observed, as expected from considerations of the desorption and ionization mechanism. Interday and intraday accuracy and precision were calculated to be within 13% and 82-114%, respectively. Estimated concentrations of proflavine residue in whole blood were also successfully obtained at selected time points after dosing. The proposed method is simple, low cost, and sensitive, and should be seen as a complementary method for monitoring drug levels in blood. Graphical Abstract Monitoring proflavine levels in rat whole blood at different time points using laser desorption postionization mass spectrometry (LDPI-MS).

Infusion of imaging and therapeutic molecules into the plant virus-based carrier cowpea mosaic virus: cargo-loading and delivery.

This work is focused on the development of a plant virus-based carrier system for cargo delivery, specifically 30nm-sized cowpea mosaic virus (CPMV). Whereas previous reports described the engineering of CPMV through genetic or chemical modification, we report a non-covalent infusion technique that facilitates efficient cargo loading. Infusion and retention of 130-155 fluorescent dye molecules per CPMV using DAPI (4',6-diamidino-2-phenylindole dihydrochloride), propidium iodide (3,8-diamino-5-[3-(diethylmethylammonio)propyl]-6-phenylphenanthridinium diiodide), and acridine orange (3,6-bis(dimethylamino)acridinium chloride), as well as 140 copies of therapeutic payload proflavine (PF, acridine-3,6-diamine hydrochloride), is reported. Loading is achieved through interaction of the cargo with the CPMV's encapsidated RNA molecules. The loading mechanism is specific; empty RNA-free eCPMV nanoparticles could not be loaded. Cargo-infused CPMV nanoparticles remain chemically active, and surface lysine residues were covalent modified with dyes leading to the development of dual-functional CPMV carrier systems. We demonstrate cargo-delivery to a panel of cancer cells (cervical, breast, and colon): CPMV nanoparticles enter cells via the surface marker vimentin, the nanoparticles target the endolysosome, where the carrier is degraded and the cargo is released allowing imaging and/or cell killing. In conclusion, we demonstrate cargo-infusion and delivery to cells; the methods discussed provide a useful means for functionalization of CPMV toward its application as drug and/or contrast agent delivery vehicle.

To dye or not to dye: a randomized, clinical trial of a triple dye/alcohol regime versus dry cord care.

OBJECTIVE: The use of antibacterial agents to clean and dry the stump of the newborn's umbilical cord after birth has recently been abandoned by many neonatal units in favor of dry cord care. The objective of this study was to compare cord bacterial colonization and morbidity among newborns whose cords were treated with triple dye and alcohol versus dry cord care. METHODOLOGY: We randomly allocated 766 newborns to either 2 applications of triple dye to the umbilical cord stump on the day of birth with alcohol swabbing twice daily until the cord fell off (n = 384) or dry care (n = 382). Dry care consisted of spot cleaning soiled skin in the periumbilical area with soap and water, wiping it with a dry cotton swab or cloth, and allowing the area to air dry. Umbilical stumps on all subjects were swabbed and cultured. Community health nurses visiting at 2 or 3 days after hospital discharge observed the stump for signs of infection. Follow-up phone calls were made to mothers within 3 weeks of discharge. RESULTS: One infant in the dry care group was diagnosed with omphalitis. The umbilical stump was colonized with alpha-hemolytic streptococcus and coagulase-negative staphylococcus. Infants in the dry care group were significantly more likely to be colonized with Escherichia coli (34.2% vs 22.1%), coagulase-negative staphylococci (69.5% vs 50.5%), Staphylococcus aureus (31.3% vs 2.8%), and group B streptococci (11.7% vs 6.0%). Community health nurses were significantly more likely to observe exudate (7.4% vs 0.3%) and foul odor (2.9% vs 0.7%) among infants allocated to the dry care group during the home visit. CONCLUSIONS: Omphalitis remains a clinical issue. Cessation of bacteriocidal care of the umbilical stump must be accompanied by vigilant attention to the signs and symptoms of omphalitis.

The effectiveness of single and multiple applications of triple dye on umbilical cord separation time.

UNLABELLED: The effectiveness of single and multiple applications of triple dye for umbilical cord care in the umbilical cord separation time (UCST) was evaluated in 180 neonates. Seven neonates were excluded, three where the cord stump separation time was uncertain and four to whom contact was lost. The participating neonates were randomly assigned to two groups. Group 1, 101 neonates, were treated with a regimen of a single application of triple dye. Group 2, 79 neonates, were treated with multiple applications of triple dye. Complete information was obtained from 97 neonates (96.2%) in group 1 and 76 (96%) in group 2. The UCST was 12.6 +/- 0.45 (mean +/- SE) days in group 1 and 16.68 +/- 0.65 days in group 2 (P < 0.0001) and showed no significant association with infants' gender, mode of delivery, gravidity, gestational age, birth weight, or hospital stay. CONCLUSION: A single application of triple dye may be a more favourable regimen with a similarly antimicrobial effect, a shorter UCST and may be more cost effective than multiple applications of triple dye in umbilical cord care.

An audit of the effect of two cord-care regimens on bacterial colonization in newborn infants.

Proper care of the umbilical cord of newborn infants may prevent later infections. When St Joseph's Hospital in Hamilton, Ontario, started using alcohol instead of triple dye for umbilical cord care, there was a dramatic increase in the incidence of bacterial colonization in newborns in the nursery and, later, in the number of cases of staphylococcus-related skin infections in infants born at the hospital. Follow-up on 1,545 infants revealed that triple dye was significantly more effective than alcohol in reducing the growth of gram-positive organisms, especially Staphylococcus aureus and group B streptococcus, and several gram-negative organisms. Because hospital medical staff had carefully collected data on bacterial colonization, they were quickly aware of the problem and could justify resuming the use of triple dye.

Umbilical cord care. A study of bacitracin ointment vs. triple dye.

Umbilical cord colonization rates were examined over a 4-year period following topical application of bacitracin (1978-1980) or triple dye (1980-1982). A total of 2402 cords were cultured: 1229 following bacitracin cord care and 1173 after triple dye application. Cords treated with bacitracin had significantly higher colonization rates when compared to triple dye prophylaxis. Bacterial colonization with Staphylococcus epidermidis and group B beta-hemolytic streptococcus was found only after bacitracin prophylaxis. Our data support the use of triple dye for routine cord care and suggest that bacitracin application may increase the rate of group B streptococcal colonization.