Treatment of Melasma with Tranexamic Acid Essence Combined with Iontophoresis: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial.

Objective: This randomized, double-blind, placebo-controlled trial aimed to evaluate the efficacy of tranexamic acid essence combined with iontophoresis in treating melasma. Methods: Thirty participants were recruited and randomly assigned to the experimental (Group A) or control group (Group B). Group A received tranexamic acid essence iontophoresis treatment twice weekly for three months, while Group B received placebo treatment. Melasma Area and Severity Index (MASI) scores and skin luminance (L) values were assessed at baseline and weeks 4, 8, and 12. Results: No significant differences in baseline characteristics were observed between the groups. The mean MASI score reduction rate was significantly higher in Group A (-0.10±0.12%) compared to Group B (-0.02±0.09%) (p<0.05). Skin L values significantly increased in Group A from 61.32±3.53 to 63.32±1.78, while slightly decreasing in Group B (p=0.037). Conclusion: Tranexamic acid essence combined with iontophoresis significantly improved MASI scores and skin luminance compared to placebo, demonstrating its effectiveness in treating melasma. Further research with larger sample sizes and longer follow-up is warranted to validate long-term effects and recurrence rates.

Evaluation test and analysis of a microneedle and iontophoresis based medical device "CELLADEEP Patch" in skin improvement on ex vivo human-derived skin tissue models.

BACKGROUND: Microneedles are tiny needles, typically ranging from tens to hundreds of micrometers in length, used in various medical procedures and treatments. The tested medical device named "CELLADEEP Patch" a dissolvable microneedle therapy system (MTS), made of hyaluronic acid and collagen. And the iontophoresis technique is also applied in the system. The study aimed to evaluate the effectiveness of the "CELLADEEP Patch" in skin improvement. METHODS: Ex vivo human-derived skin tissue models were used in this study and they were divided into three different groups, namely, the Untreated Group, the Negative Control Group, and the Test Group respectively. The Untreated Group received no treatment measures, the Negative Control Group was exposed to ultraviolet B radiation (UVB) irradiation, and the Test Group was exposed to UVB irradiation and treated with "CELLADEEP Patch". Skin moisture content, transdermal water loss, and skin elasticity were evaluated by three clinical devices. Additionally, histological staining and related mRNA expression levels were also analyzed. RESULTS: The results of skin moisture content, transdermal water loss, and skin elasticity evaluation consistently illustrated that the application of "CELLADEEP Patch" led to remarkable skin improvement. And the analysis of histological staining images also confirmed the effectiveness of the "CELLADEEP Patch", especially for increasing collagen density. Moreover, the upregulation of Collagen type 1 a (COL1A1) and hyaluronan synthase 3 mRNA expression and the decrease of Matrix metalloproteinase 1 (MMP-1) and Interleukin-1 beta (IL-1ß) mRNA expression reflected its wrinkle improvement, moisturizing and anti-inflammation function. CONCLUSION: "CELLADEPP Patch", the MTS combined with the iontophoresis technique, exhibits its effectiveness in moisturizing, skin elasticity improvement, and anti-inflammatory function when applied to ex vivo human-derived skin tissue models in experiments. The study has contributed to the understanding of the "CELLADEPP Patch" and laid the foundation for subsequent animal experiments and clinical trials.

Pretreatment of microneedles enhances passive transdermal administration of pilocarpine and pilocarpine-induced sweat production in humans.

The development of an effective transdermal drug delivery protocol to eccrine sweat glands is important for the advancement of research on the human sweating response. We investigated whether microneedle treatment prior to the application of pilocarpine, a hydrophilic and sudorific agent that does not induce sweating due to a limited percutaneous passive diffusion by skin application alone, augments sweat production. We applied three microneedle arrays to forearm skin sites simultaneously (n = 20). Upon removal of the microneedles, 1 % pilocarpine was applied to each site for 5-, 15-, and 30-min for the assessment of sweat gland function. In parallel, pilocarpine was administered by transdermal iontophoresis (5-min) at a separate site. Sweat rate was assessed continuously via the ventilated capsule technique. Pilocarpine augmented sweat rate at the 15- and 30-min periods as compared to the application at 5-min. The sweating responses induced by the 15- and 30-min application of pilocarpine were equivalent to âˆ¼ 80 % of that measured at the iontophoretically treated sites. Notably, we observed a correlation in sweat rate between these two transdermal drug delivery methods. Altogether, our findings show that pre-treatment of microneedle arrays can enhance transdermal delivery efficiency of pilocarpine to human eccrine sweat glands.

[Method of comprehensive physiotherapy of dental patients after COVID-19]. / Metod kompleksnoi fizioterapii u stomatologicheskikh patsientov posle COVID-19.

Functional gastrointestinal disorders, which had an impact on the dentofacial system (pain, loose teeth and falling out of them) in patients who have had COVID-19, drew the close attention of specialists of different profiles. The pathogenesis of worsening post-COVID edentulism is insufficiently studied, as many issues of adequate therapy remain unsolved, in which the role of non-drug technologies in the treatment of dental patients who have suffered from COVID-19 is extremely high. OBJECTIVE: To describe the mechanism of action and clinical effectiveness of the developed combined physiotherapy method, including the induced technique of piracetam iontophoresis on the frontooccipital technic and acupuncture laser therapy in dental patients with complaints of edentulism progression after COVID-19 on the basis of the analysis of single studies on the post-COVID loss of teeth treatment. MATERIAL AND METHODS: A number of patients equal 120 who complained of tooth loss after COVID-19 during the past 6 months were examined. The following initial and end points were considered: dental bleeding and inflammation scores, vascular and endothelial dysfunction markers - levels of intercellular adhesion molecules and their receptors (SlCAM-1, SVCAM-1, VEGF-A, ET-1) before and after treatment. RESULTS: Negative correlation between VEGF-A (pg/ml) concentration in peripheral blood serum and sVCAM-1 (ng/ml) level in the examined patients (r=0.4830, p<0.05) and strong inverse correlation between slCAM-1 (ng/ml) level and sVCAM-1 (r=0.7696, p<0.01) have been established. More significant effects after application of the combined induced method on the head's structures and laser acupuncture have been noted than after acupuncture laser exposure and after inducing technique separately, namely in the form of dental inflammation score correction by 1.76 times (p<0.001), decrease of bleeding score by 2.6 (p<0.05), decrease of concentration of SVCAM-1 by 1.7 times and SlCAM-1 by 2 times (p<0.001), increase of endothelin level by 1.7 times as well as the initial low VEGF-A (pg/ml) by 1.5 times (p<0.01). CONCLUSION: The developed physiotherapeutic complex, which includes laser acupuncture physiotherapy and induced technique of 5% piracetam iontophoresis, can potentially be considered as a physioprophylactic and therapeutic model of post-COVID edentulism.

Iontophoresis-coupled rapidly dissolving polymeric microneedle patch of naloxone for its enhanced transdermal delivery.

The transdermal delivery of naloxone for opioid overdose emergency purposes is a challenge due to its poor rate of diffusion through the layers of skin. This results in delayed delivery of an insufficient amount of the drug within minimal time as is desired to save lives. The ability of dissolving polymeric microneedles to shorten the lag time significantly has been explored and shown to have prospects in terms of the transdermal delivery of naloxone. This is an option that offers critical advantages to the ongoing opioid crisis, including ease of distribution and easy administration, with little to no need for intervention by clinicians. Nonetheless, this approach by itself needs augmentation to meet pharmacokinetic delivery attributes desired for a viable clinical alternative to existing market dosage forms. In this study, we report the success of an optimized iontophoresis-coupled naloxone loaded dissolving microneedle patch which had facilitated a 12- fold increase in average cumulative permeation and a 6-fold increase in drug flux over a conventional dissolving microneedle patch within 60 min of application (p < 0.05). This translates to a 30 % decrease in dose requirement in a mechanistically predicted microneedle patch established to be able to achieve the desired early plasma concentration time profile needed in an opioid overdose emergency. Applying a predictive mathematical model, we describe an iontophoresis-coupled microneedle patch design capable of meeting the desired pharmacokinetic profile for a viable naloxone delivery form through skin.

Transcutaneous Delivery of Dexamethasone Sodium Phosphate Via Microneedle-Assisted Iontophoretic Enhancement - A Potential Therapeutic Option for Inflammatory Disorders.

AIM: This study aimed to fabricate dexamethasone sodium phosphate loaded microneedle arrays (MNA) and investigate their efficiency in combination with iontophoresis for the treatment of hind paw oedema in rats. METHODS: Drug loaded polyvinyl alcohol, polyvinyl pyrrolidone and D-sorbitol-based MNA11 were fabricated by vacuum micromolding. Physicochemical, morphological, thermal, in-silico, in-vitro insertion ability (on parafilm) and drug release studies were performed. Ex-vivo permeation, in-vivo insertion and anti-inflammatory studies were performed in combination with iontophoresis. RESULTS: MNA11 displayed sharp-tipped projections and acceptable physicochemical features. Differential scanning calorimetry results indicated that drug loaded MNA11 were amorphous solids. Drug interacted with PVP and PVA predominately via hydrogen bonding. Parafilm displayed conspicuously engraved complementary structure of MNA11. Within 60 min, 91.50 ± 3.1% drug released from MNA11. A significantly higher i.e., 95.06 ± 2.5% permeation of drug was observed rapidly (within 60 min) from MNA11-iontophoresis combination than MNA11 i.e., 84.07 ± 3.5% within 240 min. Rat skin treated using MNA11 and MNA11-iontophoresis showed disruptions / microchannels in the epidermis without any damage to underlying anatomical structures. MNA11-iontophoresis combination led to significant reduction (83.02 ± 3.9%) in paw oedema as compared to MNA11 alone (72.55 ± 4.1%). CONCLUSION: MNA11-iontophoresis combination can act as a promising candidate to deliver drugs transcutaneously for treating inflammatory diseases.

Increased Fluorohydroxyapatite across Dentin after Fluoride Iontophoresis.

Due to the multiple factors contributing to dentin demineralization and hypersensitivity among individuals, the effectiveness of the available treatments in the long term remains unclear. A recent study reported a simple strategy to potentially mimic natural remineralization with increased crystallization on the enamel caries using fluoride iontophoresis. Such an effect is also ideal for accomplishing dentin biomineralization and structural strength. This study aimed to investigate structural and compositional characteristics and permeability changes after fluoride iontophoresis with different polarities, cathodal iontophoresis (CIP), anodal iontophoresis (AIP), and the control without iontophoresis for the treatment of etched dentin under simulated pulpal pressure. The 24 premolars were divided into 3 groups: CIP, AIP, and topical application of 5% sodium fluoride (NaF) for 40 s. Relative to before treatment, iontophoresis with both polarities significantly decreased the permeability with a visible increase in occluding tubules containing crystal formation and growth throughout the dentin structure and depth. The CIP not only restored the etched dentin surface into a sound condition but also reinforced the dentin across the structure and depth by the synergistic effects of remineralization, increasing crystal formation and transformation toward the more crystalline structure of fluorohydroxyapatite. Following topical treatment, X-ray diffraction analysis and Raman spectra revealed a significant reduction in the crystal size and crystallinity associated with the raised B-type carbonate substitution into the hydroxyapatite compared with that in the sound dentin. The result was the first to reveal the ideal strategy to rapidly restore the etched dentin surface into a sound condition, including reinforcing the dentin across the structure and depth by the synergistic effects of decreasing permeability, increasing crystal formation, and transformation toward the more crystalline structure of fluorohydroxyapatite using the 5% NaF applied with the DC cathode iontophoresis. The technique is noninvasive and simple and deserves further development for clinical application.

Spatial targeted delivery of riboflavin with a controlled corneal iontophoresis delivery system in theranostic-guided UV-A light photo-therapy.

Seven human donor eye globes underwent corneal cross-linking using theranostic UV-A device with accessory corneal iontophoresis system for patterned delivery of a 0.22% riboflavin solution. Theranostic-guided UV-A light illumination assessed riboflavin distribution and treated corneas at 10 mW/cm2 for 9 min with a 5.0-mm beam size. Corneal topography maps were taken at baseline and 2-h post-treatment. Analysis utilized corneal topography elevation data, with results showing controlled riboflavin delivery led to a consistent gradient, with 40% higher levels centrally (248 ± 79 µg/cm3) than peripherally (180 ± 72 µg/cm3 at ±2.5 mm from the center). Theranostic-guided UV-A light irradiation resulted in significant changes in corneal topography, with a decrease in best-fit sphere value (-0.7 ± 0.2 D; p < 0.001) and consistent downward shift in corneal elevation map (-11.7 ± 3.7 µm). The coefficient of variation was 2.5%, indicating high procedure performance in achieving significant and reliable corneal flattening.

Microneedle combined with iontophoresis and electroporation for assisted transdermal delivery of goniothalamus macrophyllus for enhancement sonophotodynamic activated cancer therapy.

The underlying study was carried out aiming at transdermal drug delivery (TDD) of Goniothalamus macrophyllus as sono-photo-sensitizer (SPS) using microneedle (MN) arrays with iontophoresis (MN-IP), electroporation (MN-EP) in conjunction with applying photodynamic therapy (PDT), sonodynamic therapy (SDT) and sono-photodynamic therapy (SPDT) as an up-to-date activated cancer treatment modality. Study was conducted on 120 male Swiss Albino mice, inoculated with Ehrlich ascites carcinoma (EAC) divided into 9 groups. We employed three different arrays of MN electrodes were used (parallel, triangular, and circular), EP, IP with different volts (6, 9, 12 V), an infrared laser and an ultrasound (pulsed and continuous wave) as our two energy sources. Results revealed that parallel 6 V TDD@MN@IP@EP can be used as effective delivery system for G. macrophyllus from skin directly to target EAC cells. In addition MN@IP@EP@TDD G. macrophyllus is a potential SPS for SPDT treatment of EAC. With respect to normal control mice and as opposed to the EAC untreated control mice, MN@EP@IP TDD G. macrophyllus in the laser, ultrasound, and combination activated groups showed a significant increase in the antioxidant markers TAC level and the GST, GR, Catalase, and SOD activities, while decrease in lipid peroxidation oxidative stress parameter MDA levels. In addition significantly increased apoptotic genes expressions (p53, caspase (3, 9), Bax, and TNF alpha) and on the other hand decreased anti- apoptotic (Bcl-2) and angiogenic (VEGF) genes expressions. Moreover significantly ameliorate liver and kidney function decreasing ALT, AST, urea and creatinine respectively. Furthermore MN@IP@EP@TDD G. macrophyllus combined with SPDT was very effective at reducing the growth of tumors and even causing cell death according to microscopic H&E stain results. This process may be related to a sono- and/or photochemical activation mechanism. According to the findings, MN@IP@EP@TDD G. macrophyllus has a lot of potential as a novel, efficient delivery method that in combination with infrared laser and ultrasound activation SPDT demonstrated promising anticancer impact for treating cancer.

Anticolinérgicos tópicos en el manejo de la hiperhidrosis focal en adultos y niños. Una revisión narrativa / Topical Anticholinergics in the Management of Focal Hyperhidrosis in Adults and Children. A Narrative Review

La hiperhidrosis se caracteriza por excesiva sudoración, habitualmente secundaria a disfunción autonómica con hipersecreción de las glándulas sudoríparas ecrinas. La hiperhidrosis primaria focal es la forma más frecuente, y afecta axilas, palmas, plantas y/o cara. Frecuentemente genera un gran impacto en la calidad de vida y en la actividad social. Su tratamiento es complejo. Los antitranspirantes tópicos son recomendados en primer lugar en la mayoría de casos de hiperhidrosis leve. Múltiples ensayos clínicos y estudios prospectivos avalan la eficacia y tolerabilidad de los anticolinérgicos orales y tópicos. En casos moderado/graves, el glicopirronio tópico, el cual ha sido evaluado en al menos 8 ensayos clínicos con más de 2.000 pacientes en total, podría ser considerado la primera línea farmacológica en la hiperhidrosis axilar mal controlada con antitranspirantes tópicos; seguido por inyecciones de toxina botulínica, sistemas de microondas y por anticolinérgicos orales. En este artículo revisamos el rol de los anticolinérgicos tópicos en el manejo de la hiperhidrosis focal en adultos y niños.(AU)

Hyperhidrosis, or excessive sweating, is characterized by overactivity of the eccrine sweat glands, usually associated with dysfunction of the autonomic nervous system. Primary focal hyperhidrosis is the most common form and can affect the axillae, palms, soles, and/or face, often leading to significantly impaired quality of life and social functioning. Treatment is complex. Topical antiperspirants are normally recommended as the first-line treatment for mild hyperhidrosis. Multiple clinical trials and prospective studies support the efficacy and tolerability of oral and topical anticholinergics in the management of hyperhidrosis. Topical glycopyrronium, which has been investigated in at least 8 clinical trials enrolling more than 2000 patients, is probably the first-line pharmacological treatment for axillary hyperhidrosis in patients with moderate to severe disease poorly controlled with topical antiperspirants. Second-line treatments include botulinum toxin injections, microwave treatment, and oral anticholinergics. We review the use of topical anticholinergics in the management of focal hyperhidrosis in adults and children.(AU)

[Translated article] Topical Anticholinergics in the Management of Focal Hyperhidrosis in Adults and Children. A Narrative Review / Anticolinérgicos tópicos en el manejo de la hiperhidrosis focal en adultos y niños. Una revisión narrativa

La hiperhidrosis se caracteriza por excesiva sudoración, habitualmente secundaria a disfunción autonómica con hipersecreción de las glándulas sudoríparas ecrinas. La hiperhidrosis primaria focal es la forma más frecuente, y afecta axilas, palmas, plantas y/o cara. Frecuentemente genera un gran impacto en la calidad de vida y en la actividad social. Su tratamiento es complejo. Los antitranspirantes tópicos son recomendados en primer lugar en la mayoría de casos de hiperhidrosis leve. Múltiples ensayos clínicos y estudios prospectivos avalan la eficacia y tolerabilidad de los anticolinérgicos orales y tópicos. En casos moderado/graves, el glicopirronio tópico, el cual ha sido evaluado en al menos 8 ensayos clínicos con más de 2.000 pacientes en total, podría ser considerado la primera línea farmacológica en la hiperhidrosis axilar mal controlada con antitranspirantes tópicos; seguido por inyecciones de toxina botulínica, sistemas de microondas y por anticolinérgicos orales. En este artículo revisamos el rol de los anticolinérgicos tópicos en el manejo de la hiperhidrosis focal en adultos y niños.(AU)

Hyperhidrosis, or excessive sweating, is characterized by overactivity of the eccrine sweat glands, usually associated with dysfunction of the autonomic nervous system. Primary focal hyperhidrosis is the most common form and can affect the axillae, palms, soles, and/or face, often leading to significantly impaired quality of life and social functioning. Treatment is complex. Topical antiperspirants are normally recommended as the first-line treatment for mild hyperhidrosis. Multiple clinical trials and prospective studies support the efficacy and tolerability of oral and topical anticholinergics in the management of hyperhidrosis. Topical glycopyrronium, which has been investigated in at least 8 clinical trials enrolling more than 2000 patients, is probably the first-line pharmacological treatment for axillary hyperhidrosis in patients with moderate to severe disease poorly controlled with topical antiperspirants. Second-line treatments include botulinum toxin injections, microwave treatment, and oral anticholinergics. We review the use of topical anticholinergics in the management of focal hyperhidrosis in adults and children.(AU)

The impact of skin color and tone on histamine iontophoresis and Doppler flowmetry measurements as a pharmacodynamic biomarker.

The phenotypical manifestations of asthma among children are diverse and exhibit varying responses to therapeutic interventions. There is a need to develop objective biomarkers to improve the characterization of allergic and inflammatory responses relevant to asthma to predict therapeutic treatment responses. We have previously investigated histamine iontophoresis with laser Doppler flowmetry (HILD) as a potential surrogate biomarker that characterizes histamine response and may be utilized to guide the treatment of allergic and inflammatory disease. We have identified intra-individual variability of HILD response type among children and adults with asthma and that HILD response type varied in association with racial classification. As laser Doppler flowimetry may be impacted by skin color, we aimed to further validate the HILD method by determining if skin color or tone is associated with observed HILD response type differences. We conducted an observational study utilizing quantification of skin color and tone obtained from photographs of the skin among participants during HILD assessments via the RGB color model. We compared RGB values across racial, ethnic, and HILD response type via the Kruskal-Wallis test and calculated Kendall rank correlation coefficient to evaluate the relationship between RGB composite scores and HILD pharmacodynamic measures. We observed that RGB scores differed among racial groups and histamine response phenotypes (p < 0.05). However, there was a lack of correlation between the RGB composite score and HILD pharmacodynamic measures (r values 0.1, p > 0.05). These findings suggest that skin color may not impact HILD response variations, necessitating further research to understand previously observed differences across identified racial groups.

Comparative evaluation of physical and chemical enhancement techniques for transdermal delivery of linagliptin.

Linagliptin is a dipeptidyl peptidase-4 inhibitor used for the management of type-2 diabetes. US FDA-approved products are available exclusively as oral tablets. The inherent drawbacks of the oral administration route necessitate exploring delivery strategies via other routes. In this study, we investigated the feasibility of transdermal administration of linagliptin through various approaches. We compared chemical penetration enhancers (oleic acid, oleyl alcohol, and isopropyl myristate) and physical enhancement techniques (iontophoresis, sonophoresis, microneedles, laser, and microdermabrasion) to understand their potential to improve transdermal delivery of linagliptin. To our knowledge, this is the first reported comparison of chemical and physical enhancement techniques for the transdermal delivery of a moderately lipophilic molecule. All physical enhancement techniques caused a significant reduction in the transepithelial electrical resistance of the skin samples. Disruption of the skin's structure post-treatment with physical enhancement techniques was further confirmed using characterization techniques such as dye binding, histology, and confocal microscopy. In vitro permeation testing (IVPT) demonstrated that the passive delivery of linagliptin across the skin was < 5 µg/sq.cm. Two penetration enhancers - oleic acid (93.39 ± 8.34 µg/sq.cm.) and oleyl alcohol (424.73 ± 42.86 µg/sq.cm.), and three physical techniques - iontophoresis (53.05 ± 0.79 µg/sq.cm.), sonophoresis (141.13 ± 34.22 µg/sq.cm.), and laser (555.11 ± 78.97 µg/sq.cm.) exceeded the desired target delivery for therapeutic effect. This study established that linagliptin is an excellent candidate for transdermal delivery and thoroughly compared chemical penetration and physical transdermal delivery strategies.

Comparison of the clinical efficacy of topical tretinoin 0.05% cream and tacrolimus 0.1% ointment plus iontophoresis in the management of palmoplantar psoriasis.

BACKGROUND: Palmoplantar psoriasis (PPP) is a localized variant of psoriasis that may be resistant to topical therapy, owing to the poor penetrability of topical agents at this anatomical site. Modalities that enhance localized cutaneous delivery of drugs could help to solve this problem. Iontophoresis is one such procedure that augments transdermal drug delivery, thus enabling better and expeditious therapeutic outcomes. OBJECTIVE: To compare the therapeutic efficacy and safety of iontophoresis with tretinoin 0.05% cream and tacrolimus 0.1% ointment in treating patients with PPP. METHODS: Sixty patients with PPP (28 males and 32 females, age range 8-76 years) were enrolled and randomly assigned to one of two groups comprising 30 patients each. One group (12 males and 18 females) received iontophoresis with tretinoin 0.05% cream; the other (16 males and 14 females) received iontophoresis treatment with tacrolimus 0.1% ointment. Both groups received treatment weekly from baseline until 4 weeks and then fortnightly at weeks 6 and 8. Clinical images were taken at each visit and improvement of psoriasis was evaluated using the erythema, scaling, induration and fissuring (ESIF) score. The percentage reduction in ESIF score was also assessed on completion of treatment and the grade of improvement noted for each patient. RESULTS: Twenty-seven patients in the iontophoresis with tretinoin 0.05% cream group and 29 in the iontophoresis treatment with tacrolimus 0.1% ointment group completed the study. The mean (SD) ESIF score in the former decreased significantly from 8.7 (2) at baseline to 3.2 (1.7) at the study endpoint (P < 0.001). Similarly, in the latter group, there was a substantial reduction in mean (SD) ESIF score from 8.2 (1.9) at baseline to 3.3 (1.1) at the study end (P < 0.001). No significant adverse effects were encountered in either treatment arm. CONCLUSIONS: Iontophoresis using tretinoin and tacrolimus was found to be effective and safe for the treatment of PPP. Although iontophoresis with tretinoin showed slightly better results than with tacrolimus, these were not statistically significant.

Analysis of the effect of calcium ions on promoting the penetrability of riboflavin into the corneal stroma by iontophoresis.

PURPOSE: To investigate the effect of calcium ions on promoting the penetrability of riboflavin into the corneal stroma by iontophoresis and to analyse the possible mechanism. METHODS: Forty rabbits were divided into five groups randomly: 0.1% riboflavin-balanced salt solution (BSS) by iontophoresis group, 0.1% riboflavin-saline solution by iontophoresis group, 0.1% riboflavin-zinc gluconate solution by iontophoresis group, 0.1% riboflavin-calcium gluconate solution by iontophoresis group and classical riboflavin instillation after corneal de-epithelialization as the control group. The riboflavin concentrations in corneal stroma were determined and compared by high-performance liquid chromatography (HPLC) after removing epithelium and endothelium. RESULTS: Iontophoretic delivery of a 0.1% riboflavin-calcium gluconate solution was the closest to the effect of classical de-epithelialization. The other solvents were unsufficient at enhancing the permeability of the riboflavin. CONCLUSION: Calcium ions can promote the penetrability of riboflavin into the corneal stroma by iontophoresis.

Rate and predictors of insufficient sweat volume in very young infants after pilocarpine gel iontophoresis: prospective, population-based study.

OBJECTIVE: To verify the rate and predictors of 'quantity not sufficient' (QNS) among Brazilian infants younger than 3 months with positive newborn screening (NBS) for cystic fibrosis (CF). DESIGN: Prospective, population-based study. SETTING: Public Statewide Newborn Screening Programme where the incidence rate of CF is ≈1:11 000. PATIENTS: Subjects with positive two-tiered immunoreactive trypsinogen. INTERVENTIONS: Sweat induction and collection were performed in the same facility; one sweat sample was obtained per individual. MAIN OUTCOME MEASURES: The QNS rate and its predictors; analysis corresponded to the day of sweat collection. RESULTS: Among the 975 participants, QNS rates for 10 and 15 µL were 3.6% (95% CI 2.5% to 4.9%) and 8.3% (95% CI 6.6% to 10.2%). Infants weighing >3056 and >3845 g and with gestational age higher than 37 weeks had a greater likelihood (5.5 and 6.7, and 2.7 and 5.8 times more, respectively) of avoiding QNS than their peers. CONCLUSION: QNS rates fulfilled the requirements, but predictors differed from those recommended by the Cystic Fibrosis Foundations guidelines.

Development of an Effective Psoriasis Treatment by Combining Tacrolimus-Encapsulated Liposomes and Iontophoresis.

Psoriasis is a chronic T-cell-mediated autoimmune skin disease. Tacrolimus (FK506) is commonly used treatment for psoriasis. However, since the molecular weight of FK506 is more than 500 Da, its skin penetration is limited, so that there is a need to improve the penetrability of FK506 to allow for more effective treatment. To this end, we employed iontophoresis (ItP), which is a physical, intradermal drug delivery technology that relies on the use of weak electric current. Previous findings suggest that activation of cell signaling by the weak electric current applied during ItP may affect the expression of inflammatory cytokines, leading to aggravation of psoriasis. In this study, we analyzed the effect of ItP on the expression of various inflammatory cytokines in the skin, and subsequently examined the therapeutic effect of ItP using negatively-charged liposomes encapsulating FK506 (FK-Lipo) in a rat psoriasis model induced by imiquimod. We found that ItP (0.34 mA/cm2, 1 h) did not affect mRNA levels of inflammatory cytokines or epidermis thickness, indicating that ItP is a safe technology for psoriasis treatment. ItP of FK-Lipo suppressed the expression of inflammatory cytokines induced by imiquimod treatment to a greater extent than skin treated with FK506 ointment for 1 h. Furthermore, epidermis thickening was significantly suppressed only by ItP of FK-Lipo. Taken together, results of this study demonstrate the successful development of an efficient treatment for psoriasis by combining FK-Lipo and ItP, without disease aggravation associated with the weak electric current.

Clinical Results of Accelerated Iontophoresis-Assisted Epithelium-on Corneal Cross-linking for Progressive Keratoconus in Children.

PURPOSE: To evaluate the clinical characteristics of pediatric patients with progression of keratoconus after accelerated iontophoresis-assisted epithelium-on corneal cross-linking (I-ON CXL) and to assess the efficacy and safety of re-treatment using accelerated epithelium-off CXL (epi-OFF CXL). METHODS: Sixteen eyes of 16 patients (mean age: 14.6 ± 2.5 years) with keratoconus underwent I-ON CXL. The main outcome measures were uncorrected distance visual acuity, corrected distance visual acuity, maximum keratometry index (Kmax), minimum corneal thickness, elevation front and elevation back measured at the thinnest point, total higher order aberrations root main square (HOA RMS), coma RMS, and spherical aberration. An increment of Kmax greater than 1.00 diopter (D) and a decrease of greater than 20 µm in pachymetry were considered to determine the progression of keratoconus. Patients with progression of keratoconus after I-ON CXL were re-treated using an epi-OFF CXL protocol. RESULTS: Two years after I-ON CXL, 12 patients showed progression of keratoconus, whereas 4 patients were stable. There was significant worsening of Kmax (P = .04) and steepest keratometric reading (P = .01). Furthermore, a significant correlation was documented between progression of keratoconus and age (P = .02). These patients were re-treated using an epi-OFF protocol and after 2 years all patients were stable, and a statistically significant reduction of the mean Kmax (P = .007), HOA RMS (P = .05), and coma RMS (P = 05) was observed. CONCLUSIONS: I-ON CXL was ineffective in the treatment of pediatric keratoconus in younger children, whereas it had an efficacy of 2 years in older children. Re-treatment using epi-OFF CXL proved effective to halt progression of keratoconus after I-ON CXL failure. [J Pediatr Ophthalmol Strabismus. 2024;61(1):44-50.].