Effect of iontophoresis on fluoride uptake in enamel with artificial caries lesion

Abstract: Iontophoresis is a noninvasive technique, based on the application of a constant low-intensity electric current to facilitate the release of a variety of drugs, whether ionized or not, through biological membranes. The objective of this research was to evaluate the effect of iontophoresis using different electric current intensities on the uptake of fluoride in dental enamel with artificial caries lesions. In this in vitro operator-blind experiment, bovine enamel blocks (n = 10/group) with caries-like lesions and predetermined surface hardness were randomized into 6 groups: placebo gel without fluoride applied with a current of 0.8 mA (negative control), 2% NaF gel without application of any current, and 2% NaF gel applied with currents of 0.1, 0.2, 0.4 and 0.8 mA. Cathodic iontophoresis was applied for 4 min. The concentration of loosely bound fluoride (calcium fluoride) and firmly bound fluoride (fluorapatite) was determined. The results were analyzed by the nonparametric Kruskal-Wallis and Dunn tests. Iontophoresis at 0.8 mA, combined with the application of fluoridated gel (2% NaF), increased fluoride uptake in enamel with caries-like lesions, as either calcium fluoride or fluorapatite.

Physical methods for topical skin drug delivery: concepts and applications

Topical drug delivery is an interesting approach to treat skin diseases and to avoid pain and low patient compliance in cases where a systemic delivery is required. However, the stratum corneum, which is the outermost skin layer, strongly protects the body from the entrance of substances, especially those hydrophilic. In this context, different physical methods have been studied to overcome the stratum corneum barrier and facilitate penetration of drugs into or through the skin. Among them, iontophoresis, low-frequency ultrasound and microneedles have been widely employed for transdermal drug delivery. More recently, they are also studied to aid in the treatment of dermatological disorders, such as skin tumors and inflammation. Basically, iontophoresis refers to the movement of charged and non-charged hydrophilic molecules through the skin due to the application of a low constant electric current and the contributions of electromigration and electroosmosis. In low-frequency ultrasound, cavitation is the main mechanism for skin permeabilization that consists on the formation of microbubbles that disorganize the stratum corneum. Microneedles are microprojections, minimally invasive, that can be designed with different lengths, materials and geometry to increase skin permeability. In this review, concepts, mechanisms and applications of these three physical methods will be presented and discussed with focus on their use in dermatological treatments. Moreover, comparative studies using different physical methods will be presented and also some clinical perspectives will be addressed

Synergistic effect of iontophoresis and chemical enhancers on transdermal permeation of tolterodine tartrate for the treatment of overactive bladder

Purpose The objective of the study was to evaluate the synergistic transdermal permeation effect of chemical enhancers and iontophoresis technique on tolterodine tartrate (TT) transdermal gel and to evaluate its pharmacokinetic properties. Materials and Methods Taguchi robust design was used for optimization of formulations. Skin permeation rates were evaluated using the Keshary-chein type diffusion cells in order to optimize the gel formulation. In-vivo studies of the optimized formulation were performed in a rabbit model and histopathology studies of optimized formulation were performed on rats. Results Transdermal gels were formulated successfully using Taguchi robust design method. The type of penetration enhancer, concentration of penetration enhancer, current density and pulse on/off ratio were chosen as independent variables. Type of penetration enhancer was found to be the significant factor for all the responses. Permeation parameters were evaluated when maximum cumulative amount permeated in 24 hours (Q24) was 145.71 ± 2.00µg/cm2 by CIT4 formulation over control (91.89 ± 2.30µg/cm2). Permeation was enhanced by 1.75 fold by CIT4 formulation. Formulation CIT4 containing nerolidol (5%) and iontophoretic variables applied (0.5mA/cm2 and pulse on/off ratio 3:1) was optimized. In vivo studies with optimized formulation CIT4 showed increase in AUC and T1/2 when compared to oral suspension in rabbits. The histological studies showed changes in dermis indicating the effect of penetration enhancers and as iontophoresis was continued only for two cycles in periodic fashion so it did not cause any skin damage observed in the slides. Conclusion Results indicated that iontophoresis in combination with chemical enhancers is an effective method for transdermal administration of TT in the treatment of overactive bladder. .

Transdermal iontophoretic delivery of timolol maleate

Transdermal iontophoresis would be a promising method for the systemic delivery of water soluble and ionic drugs of relatively high molecular size, including peptides. The objective of the present study was to investigate the effect of biological variable such as guinea pig and human cadaver skin and other variables like drug concentration, current density on the transdermal iontophoretic transport of timolol maleate. The permeation profile of drug using solution and gel formulation was studied and compared. For better bioavailability, better patient compliance, and enhanced delivery, an iontophoretic drug delivery system of a timolol maleate matrix gel was formulated using Carbopol 974P. The study was conducted using silver-silver chloride electrodes across the guinea pig and human cadaver skin. Viscosity measurements and flux calculations indicated the suitability of the Carbopol 974P gel for transdermal iontophoretic delivery of timolol maleate. Anodal iontophoresis with silver-silver chloride electrode significantly increased the timolol maleate skin permeation as compared with the passive permeation study. The amount of timolol maleate transported during iontophoresis was significantly different among the different skins. However, iontophoretic gel formulations provided required flux of drug through human cadaver skin.

A iontoforese transdérmica seria um método promissor para a liberação sistêmica de fármacos solúveis em água e iônicos de relativamente elevado tamanho molecular, incluindo peptídeos. O objetivo do presente estudo foi investigar o efeito da variável biológica, tais como cobaia e pele de cadáver humano, e outras variáveis como concentração do fármaco, densidade de corrente sobre o transporte transdérmico iontoforético de maleato de timolol. Comparou-se o perfil de permeação do fármaco usando a formulação de solução e de gel. Para melhor biodisponibilidade, melhor adesão do paciente e liberação aprimorada, formulou-se sistema de liberação iontoforética gel de maleato de timolol usando Carbopol 974P. O estudo foi conduzido usando eletrodos de prata-cloreto de prata na cobaia e na pele de cadáver humano. Medidas de viscosidade e de fluxo indicaram a adequação do gel Carbopol 974 P para liberação iontoforética transdérmica do maleato de timolol. A iontoforese anódica com eletrodo de prata-cloreto de prata aumentou significativamente a permeação dérmica do maleato de timolol, comparativamente à permeação passiva. A quantidade de maleato de timolol transportado durante a iontoforese foi significativamente diferente entre as diferentes peles . No entanto, as formulações iontoforéticas de gel forneceram o fluxo necessário do fármaco através da pele de cadáver humano.

O uso da corrente polarizada na fisioterapia / Using polarized current in physiotherapy

JUSTIFICATIVA E OBJETIVOS: A corrente polarizada pode ser utilizada em diferentes tipos de lesões, contudo a literatura é escassa no campo fisioterapêutico. O objetivo deste estudo foi apresentar por meio de revisão da literatura os efeitos da corrente polarizada e explorar suas diferentes formas de aplicação pela fisioterapia. CONTEÚDO: Utilizaram-se os bancos de dados LILACS, Medlinee Scielo com as seguintes palavras-chave: corrente polarizada;corrente galvânica; corrente farádica; corrente exponencial; correntes Diadinâmicas de Bernard; corrente de alta voltagem;microcorrente; iontoforese. Foram revisadas 13 referências bibliográficas, do período de 1983 a 2009, além do uso de estudos não indexados a essas bases de dados para a contextualização do assunto. Encontrou-se que esse tipo de corrente proporciona benefícios à pacientes com complicações traumato-ortopédicas, neurológicas, desportivas ou até mesmo pós-mastectomia, em virtude de seu efeito analgésico, anti-inflamatório, vascular, eletroestimulador, cicatricial e ósseo. CONCLUSÃO: A analgesia, os efeitos vasculares e cicatriciais são os mais citados pelos estudos encontrados, destacando-se o uso da corrente diadinâmica de Bernard e da corrente de alta voltagem. No entanto, outros estudos deverão ser realizados para que maiores conclusões sejam obtidas.

BACKGROUND AND OBJETIVES: The polarized current can be used in different types of injuries, but the literature is scarce in the physical therapy . The aim of this study was to present through literature the effects of polarized current and explore different ways of applying for physiotherapy. CONTENTS: We used the databases LILACS, Medline and Scielo with the following keywords: polarized current, galvanic current,faradic current; current exponential; diadynamic Bernard; high voltage current, microcurrent, iontophoresis. 13 references were reviewed from the period 1983 to 2009, and the use of other not indexed studies for the contextualization of the subject. Found that this type of current provides benefits to patients with trauma-orthopedic complications, neurological, sports or evenpost mastectomy because of their analgesic effect, anti-inflammatory,vascular, nerve stimulators and bone healing. CONCLUSION: Analgesia, the vascular and tissue healing effects are the most cited studies found by polarized current, especially the use of diadynamic Bernard current and high voltage current. However, other studies should be conducted to further conclusions can be made.

Repeatability of the evaluation of systemic microvascular endothelial function using laser doppler perfusion monitoring: clinical and statistical implications

OBJECTIVE: An awareness of the repeatability of biological measures is required to properly design and calculate sample sizes for longitudinal interventional studies. We investigated the day-to-day repeatability of measures of systemic microvascular reactivity using laser Doppler perfusion monitoring. METHODS: We performed laser Doppler perfusion monitoring in combination with skin iontophoresis using acetylcholine and sodium nitroprusside as well as post-occlusive reactive and thermal hyperemia twice within two weeks. The repeatability was assessed by calculating the within-subject standard deviations, limits of agreement, typical errors and intra-class correlation coefficients between days 1 and 2. The ratio of the within-subject standard deviation to the mean values obtained on days 1 and 2 (within-subject standard deviation/GM) was used to determine the condition with the best repeatability. RESULTS: Twenty-four healthy subjects, aged 24.6 + 3.8 years, were recruited. The area under the curve of the vasodilatory response to post-occlusive reactivity showed marked variability (within-subject standard deviation/GM = 0.83), while the area under the curve for acetylcholine exhibited less variability (within-subject standard deviation/ GM = 0.52) and was comparable to the responses to sodium nitroprusside and thermal treatment (within-subject standard deviations/GM of 0.67 and 0.56, respectively). The area under the blood flow/time curve for vasodilation during acetylcholine administration required the smallest sample sizes, the area under the blood flow/time curve during post-occlusive reactivity required the largest sample sizes, and the area under the blood flow/time curves of vasodilation induced by sodium nitroprusside and thermal treatment required intermediate sizes. CONCLUSIONS: In view of the importance of random error related to the day-to-day repeatability of laser Doppler perfusion monitoring, we propose an original and robust statistical methodology for use in designing prospective clinical studies.

Comparative efficacy of two treatment modalities for dentinal hypersensitivity: A clinical trial.

Background: Dentin hypersensitivity is a recurrent condition causing discomfort and sometimes pain to the patient, which also deters him from maintaining adequate oral hygiene. Home care and office measures are used for treatment of this malady. Aim: To evaluate and compare the efficacy of 2 treatment modalities for dentinal hypersensitivity, iontophoresis with acidulated phosphate gel (APF) gel, and dentin-bonding agent application. Materials and Methods: This split mouth randomized clinical study recruited subjects with a history of hypersensitivity with at least 2 teeth, verified by a light stroke with a dental explorer along the cervical third of the teeth. The patients were subjected to a 1-s air blast and cold water stimuli and their responses were recorded on a verbal rating scale. A total of 30 sites from 15 patients were divided into Group A-1.23% APF gel iontophoresis; and Group B-aqueous solution of hydroxyl-ethyl-methacrylate and glutaraldehyde. The teeth were evaluated immediately after the treatment and at the end of 2 weeks. In case of failure, the tooth was retreated with the same agent as before. Results: The results were statistically analyzed using Kruskal-Wallis analysis of variance and Mann-Whitney U tests. There was no statistically significant difference between the groups at the end of 2 weeks. However, Group A was more effective clinically, with fewer number of failures compared with Group B. Conclusion: Both the agents showed a statistically significant reduction in sensitivity compared with baseline; however, APF gel iontophoresis was more effective in reducing hypersensitivity over a longer time period.

Comparative evaluation of different strengths of electrical current in the management of dentinal hypersensitivity.

Background : Dentinal hypersensitivity is a commonly occurring but less understood and poorly managed problem of the teeth. Iontophoresis is a technique wherein desensitizing agents can be transferred under electrical pressure into the tooth structure to manage hypersensitivity. Aim : The purpose of present study is to compare the effect of different strengths of electrical current used for varying lengths of time, keeping the electrical dosage constant with the iontophoretic unit in the management of dentinal hypersensitivity. Materials and Methods : This study was conducted among the patients attending the Periodontal Department of the Government Dental College and Hospital, Patiala, Punjab, specifically complaining of tooth hypersensitivity. The Verbal Rating Scale (VRS) was used to record scores pre-, during, and post-treatment. Ten percent SrCl2 solution was applied with an iontophoretic unit. Three applications were performed at weekly intervals, up to the second week, using the same electric current dosage. The data compiled was statistically analyzed. Results : A remarkable reduction in dentinal hypersensitivity to both air blast and cold water stimuli was noted at the end of two months after iontophoresis with each current group / method, namely, I (0.25 mA for 4 minutes), II (0.5 mA for 2 minutes), and III (1 mA for 1 minute). However, the differences in effectiveness / improvement within the three current groups during the entire duration of the study were found to be statistically insignificant. Conclusion : Within the limits of this study, it could be implied that for relieving hypersensitivity, iontophoresis for all three current groups was almost equally effective, and it was found that repeated applications (up to three) gave good relief. Iontophoresis was found to be effective and safe.

Estudo da microcirculação na hanseníase virchowiana com o uso da microscopia de luz ortogonal polarizada e com laser-doppler fluxometria / Study of microcirculation in lepromatous leprosy with the use of orthogonal polarized light microscopy and laser doppler flowmetry

A hanseníase é uma doneça infecciosa com características únicas, dentre elas o fato de atingir intensamente a inervação da pele e seus anexos. Entremeando estes anexos, está a microcirculação cutânea, que a principio também tem sua inervação comprometida. Vários artigos apontam para alterações de disautonomia microcirculatória, citando como exemplo as alterações no reflexo vasomotor. O presente estudo se propõe a avaliar a microcirculação cutânea na hanseníase virchowiana, tanto em sua morfologia quanto em sua reatividade vascular. Para isto, utilizamos a tecnologia de luz ortogonal polarizada através do equipamento Cytoscan, a análise de Fourier do sinal do laser Doppler para estudo da vasomotricidade e o laser Dopplerfluxometria associado à iontoforese de substâncias vasoativas (acetilcolina, nitroprussiato de sódio e noradrenalina) para avaliação da reatividade vascular. Dez pacientes portadores de hanseníase virchowiana sem outras comorbidades que pudessem alterar os parâmetros microcirculatórios, foram avaliados pelos métodos descritos e seus resultados foram comparados aos de dez controles sem hanseníase ou qualquer outra comorbidade. Em relação à vasomotricidade não foram observadas alterações estatisticamente significativas entre os grupos, o que fala a favor da teoria de origem miogênica para a vasomotricidade. Em relação à iontoforese de substâncias vasoativas constatou-se uma diminuição da resposta vasodilatadora à acetilcolina e ao nitroprussiato nos pacientes com hanseníase. Os exames com o Cytoscan mostraram aumento no tamanho dos capilares, bem como alterações em sua morfologia. Os resultados apresentados sugerem que, provavelmente devido ao longo período de alteração inervatória decorrente da hanseníase virchowiana, estes pacientes apresentam uma alteração significativa tanto morfológica quanto na reatividade vascular da microcirculação cutânea.

Leprosy is an infectious disease with unique characterístics. One of them is the fact that it compromises not only the cutaneous and adnexial innervation, but also the innervation of the cutaneous microcirculation. Several articles indicate the impact of disautonomy on the microcirculatory level, citing the example of changes in vasomotor level. The present study proposes to evaluate morphology and microvascular reactivity of the cutaneous microcirculation of the virchowian leprosy. Methods employed in the study were: the Cytoscan, which uses the orthogonal polarized light, the Fourier analysis of the laser Doppler signal to study vasomotion, and the laser Doppler flowmetry associated with iontophoresis of vasoactive substances (acetylcholine, sodium nitroprusside and norepinephrin). Ten patients with virchowian leprosy, without any other comorbidity that could modify the microvascular parameters were evaluated and their results were compared to ten controls without leprosy or any other comorbidity. Regarding the vasomotion, no statistical significant differences were noticed between the groups. Our data are in agreement with the vasomotion's miogenic origin theory. According to iontophoresis of vasoactive substances, it was found that there is a reduced endothelial-dependent and endothelial-independent vasodilation in patients with leprosy while tests by direct visualization we observed an increase in the size of capillaries, as well as changes in their morphology. The results suggest that the significant changes in morphology and vascular reactivity of skin microcirculation are probably due to the long period of innervatory changes arising from leprosy.

Iontoforese no tratamento da tendinite calcárea do ombro: implicações clínicas / Iontophoresis in the treatment of calcifying tendinitis of the shoulder: clinical implications

Tendinite calcárea do ombro é caracterizada por uma calcificação reativa dos tendões e incapacidade funcional da articulação envolvida. Diversos tratamentos são realizados, entretanto, os resultados são insatisfatórios. Uma alternativa promissora, porém pouco difundida na prática fisioterápica é a iontoforese com ácido acético. Seus efeitos relacionados à desmineralização e conseqüente reabsorção dos depósitos de cálcio poderiam auxiliar no combate à causa primária dos sintomas da tendinite calcárea. O objetivo deste estudo foi realizar uma revisão da literatura a fim de determinar a real viabilidade e parâmetros adequados da iontoforese para o tratamento da tendinite calcárea do ombro. Uma pesquisa documental em bases de dados, além de um levantamento bibliográfico em livros relacionados ao tema foi realizada. Dentre os artigos revisados, os parâmetros para utilização da iontoforese no tratamento da tendinite calcárea do ombro mostraram-se similares, com exceção ao número de sessões. Redução do tamanho do depósito de cálcio, melhora da dor e da função foram citados como benefícios decorrentes dessa técnica. Porém, a escassez de estudos associada à baixa qualidade metodológica das pesquisas, dificultou a tomada de decisão quanto ao papel da iontoforese com ácido acético no tratamento da tendinite calcárea do ombro.

Calcifying tendinitis of the shoulder is characterized by a reactive calcification of tendons and functional disability of the involved joint. Several treatments were applied; however, the results are unsatisfactory. A promising alternative, but not well-known in physical therapy practice, is the iontophoresis with acetic acid. Its effects related to demineralization and resorption of calcium deposits could help to fight the primary cause of calcifying tendinitis. The aim of this study was a literature review to determine the real viability and adequate parameters of iontophoresis in calcifying tendinitis of the shoulder. It was made a search of articles in databases, and in books related to the subject. According to the reviewed studies, the parameters for iontophoresis use for the treatment of calcifying tendinitis of the shoulder were similar except for the number of sessions. Size reduction of the calcium deposits, improvement in pain and function were considered benefits of this technique. However, the studies are scarce and their poor methodological quality hinders the decision-making on the role of iontophoresis with acetic acid for the treatment of calcifying tendinitis of the shoulder.

Histamine iontophoresis on the viability of random skin flap in rats / Iontoforese de histamina na viabilidade do retalho cutâneo randômico em ratos

PURPOSE: To evaluate the effects of the histamine iontophoresis on the random skin flap viability in rats. METHODS: Sixty adult male Wistar rats were used. A cranially-based dorsal skin flap measuring 10 x 4 cm was raised and a plastic barrier was placed between the flap and its bed. After the surgical procedure, the animals were randomized into four groups (G1-G4) (n=15 each group) as follows: G1 (control) - sham electrical stimulation, G2 (electrical stimulation) - direct current electrical stimulation, G3 (histamine) - histamine and sham electrical stimulation and G4 (histamine iontophoresis) - transdermal iontophoresis of histamine. In all groups the procedures were performed immediately after the surgery and on the two subsequent days. The percentage of flap necrosis was measured on the seventh postoperative day. RESULTS: The mean and the respective standard deviation of the percentage of flap necrosis areas were as follows: G1 (control) - 47.87 ± 9.13 percent, G2 - 51.49 ± 8.19 percent, G3 - 46.33 ± 8.32 percent and G4 - 30.82 ± 11.25 percent. The G4 group presented a significantly smaller amount of flap necrosis when compared to the other groups (p<0.001). CONCLUSION: The topical administration of the histamine by iontophoresis was effective to increase the viability of the random skin flaps in rats.

OBJETIVO: Avaliar o efeito da iontoforese de histamina na viabilidade do retalho cutâneo randômico em ratos. MÉTODOS: Foram utilizados 60 ratos adultos e machos da linhagem Wistar. O retalho cutâneo de base cranial, medindo 10x4 cm, foi elevado no dorso dos animais e uma barreira plástica foi interposta entre o retalho e a área doadora. Após o procedimento operatório, os animais foram distribuídos aleatoriamente em 4 grupos (G1-G4) (n=15 em cada grupo) a saber: G1 (controle) - simulação da estimulação elétrica, G2 (estimulação elétrica) - estimulação elétrica com corrente direta, G3 (histamina) - histamina e simulação da estimulação elétrica e G4 (iontoforese de histamina) - iontoforese transdérmica de histamina. Em todos os grupos os procedimentos foram realizados imediatamente após a operação e nos 2 dias subseqüentes. A porcentagem de área de necrose foi avaliada no 7º dia pós-operatório. RESULTADOS: As médias e respectivos desvios-padrão das porcentagens de área de necrose foram: G1 (controle) - 47,87 ± 9,13 por cento, G2 - 51,49 ± 8,19 por cento, G3 - 46,33 ± 8,32 por cento and G4 - 30,82 ± 11,25 por cento. O grupo G4 apresentou menor média de área de necrose quando comparado aos demais grupos (p<0,001). CONCLUSÃO: A administração tópica de histamina por iontoforese aumentou a viabilidade do retalho cutâneo randômico em ratos.

Standardized Sweat Chloride Analysis for the Diagnosis of Cystic Fibrosis in Korea / 대한진단검사의학회지

BACKGROUND: Cystic fibrosis is a chronic progressive autosomal recessive disorder caused by the CFTR gene mutations. It is quite common in Caucasians, but very rare in Asians. Sweat chloride test is known to be a screening test for the cystic fibrosis due to the fact that electrolyte levels in sweat are elevated in patients. In this study, sweat chloride levels in Korean population were measured and analyzed by using standardized pilocarpine iontophoresis sweat chloride test. METHODS: The sweat chloride test was performed in 47 patients referred to Yondong Severance Hospital from August, 2001 to April, 2007 and 41 healthy volunteers. The sweat chloride tests were conducted according to the CLSI C34-A2 guideline using pilocarpine iontophoresis method, and the chloride concentrations in sweat were measured by mercurimetric titration. RESULTS: Four patients showed sweat chloride concentrations higher than 60 mmol/L. Reference interval was calculated as 1.4-44.5 mmol/L by analysis of the results of healthy volunteers (n=41). Four patients who exhibited high sweat chloride levels, had characteristic clinical features of cystic fibrosis and their diagnoses were confirmed either by repeated sweat chloride test or genetic analysis. CONCLUSIONS: Standardized sweat chloride test can be utilized as a useful diagnostic tool for cystic fibrosis in Koreans. In cases of sweat chloride levels higher than 40 mmol/L, the test should be repeated for the possible diagnosis of cystic fibrosis. All the confirmed Korean cases of cystic fibrosis showed sweat chloride level above 60 mmol/L.

Study of histamine wheal suppression by dexamethasone with and without iontophoresis.

BACKGROUND: Iontophoresis increases the penetration of drugs into the skin by electric current. The ability of topical steroids to reduce the size of the histamine wheal was used to assess the efficacy of topical dexamethasone delivered with and without iontophoresis. AIM: To determine the wheal suppressing ability of dexamethasone delivered with and without iontophoresis. METHODS: A template with three squares of 3x3 cm was placed on both forearms of 20 volunteers and the edges marked. A gauze piece soaked in 2 ml of dexamethasone solution was placed on the flexor aspect of the left forearm and the electrode, an aluminum foil was placed on it and connected to the negative pole (since dexamethasone is negatively charged). An electric current was passed for 15 minutes. Similarly, on the right forearm, a dexamethasone soaked gauze piece was placed without iontophoresis. Histamine wheal suppression was assessed at the end of 30 min, 1 hr and 2 hrs, on both sides. Statistical analysis was done using an independent t-test. RESULTS: There was a statistically significant difference in wheal suppression at 30 min (p=0.006) on the left hand where iontophoresis was used. CONCLUSION: Our experiment showed that topical dexamethasone with iontophoresis has the maximum effect at the end of 30 minutes and is more effective than dexamethasone without iontophoresis.

La prueba del sudor para el diagnostico de fibrosis quistica / The test of the sweat for the diagnosis of quística fibrosis

La fibrosis quística es un trastorno autosómico recesivo que se caracteriza por presentar enfermedad pulmonar obstructiva crónica, insuficiencia pancreática y electrolitos elevados en el sudor. El análisis cuantitativo del cloruro en el sudor, realizado en el laboratorio clínico, es considerada la prueba de elección para el diagnóstico de fibrosis quística.Palabras clave: prueba del sudor, cloruro, diagnóstico, genética, nitrato de pilocarpina, iontoforesis, tamizaje, sensibilidad, especificidad.

Iontophoresis in dermatology.

Iontophoresis is the process of increasing the penetration of drugs into the skin by application of an electric current. The drug is applied under an electrode of the same charge as the drug, and a return electrode opposite in charge to the drug is placed at a neutral site on the body surface. Electrical energy assists the movement of ions across the skin using the principle "like charges repel each other and opposite charges attract". In this article, we discuss the mechanism, principles, factors influencing iontophoresis and its application for various dermatological conditions.

Cystic Fibrosis in Korean Children: A Case Report Identified by a Quantitative Pilocarpine Iontophoresis Sweat Test and Genetic Analysis

Cystic fibrosis (CF) is inherited as an autosomal recessive trait, and the mutations in cystic fibrosis transmembrane conductance regulator (CFTR) gene contributes to the CF syndrome. Although CF is common in Caucasians, it is known to be rare in Asians. Recently, we experienced two cases of CF in Korean children. The patients were girls with chronic productive cough since early infancy. Chest computed tomography showed the diffuse bronchiectasis in both lungs, and their diagnosis was confirmed by the repeated analysis of a quantitative pilocarpine iontophoresis test (QPIT). The sweat chloride concentrations of the first patient were 108.1 mM/L and 96.7 mM/L. The genetic analysis revealed that she was the compound heterozygote of Q1291X and IVS8 T5 -M470V. In the second case, the sweat chloride concentrations were 95.0 mM/L and 77.5 mM/L. Although we performed a comprehensive search for the coding regions and exonintron splicing junctions of CFTR gene, no obvious disease-related mutations were detected in the second case. To our knowledge, this is the first report of CF in Korean children identified by a QPIT and genetic analysis. The possibility of CF should be suspected in those patients with chronic respiratory symptoms even in Korea.

Peptídeo relacionado ao gene da calcitonina por iontoforese na viabilidade de retalho cutâneo randômico em ratos / Calcitonin gene-related peptide by iontophoresis on the viability of the randon skin flaps in rats

Objetivo: Investigar o efeito da administração tópica do peptídeo relacionado ao gene da calcitonina (CGRP) por iontoforese na viabilidade de retalho cutâneo randômico em ratos. Métodos: Sessenta ratos Wistar EPM-1, adultos e machos foram submetidos a retalho cutâneo randômico. Os animais foram distribuídos aleatoriamente em quatro grupos. Nos animais do grupo 1 (controle, n=15) realizou-se simulação de estímulo elétrico, no grupo 2 (iontoforese placebo, n=15) os animais foram submetidos à corrente contínua, no grupo 3 (controle de absorção, n=15) os animais receberam simulação de estímulo elétrico com CGRP e, por fim os animais do grupo 4 (tratado, n=15) foram tratados com iontoforese de CGRP. Em todos os grupos estes procedimentos foram realizados imediatamente após a técnica operatória e nos dois dias subsequentes. A porcentagem da área de necrose foi avaliada no sétimo dia de pós-operatório. Resultados: A média das porcentagens das áreas de necrose foram: grupo 1- 48 por cento, grupo 2 - 51 por cento, grupo 3 - 46 por cento e, grupo 4 - 28 por cento. A análise estatística, através do teste de Kruskal-Wallis, evidenciou diferença significante (p<0,001). Conclusão: a administração tópica de CGRP por iontoforese é eficaz em aumentar a viabilidade de retalho cutâneo randômico em ratos.

Iontoforese no transporte ocular de drogas / Iontophoresis for ocular drug delivery

O método mais comum de administração de drogas no olho é por meio de colírios. Entretanto, por este método, não é possível atingir a concentração terapêutica nos fluidos e tecidos posteriores do olho. A administração sistêmica apresenta reduzido acesso ao segmento posterior do olho devido à presença das barreiras oculares. Injeções subconjuntivais e retrobulbares não são capazes de proporcionar níveis adequados da droga, e a injeção intravítrea é método invasivo, inconveniente e que apre-senta riscos de perfuração do bulbo ocular ou descolamento da retina. A iontoforese, no entanto, apresenta-se como alternativa para o transporte de doses terapêuticas de drogas para o segmento posterior do olho. A iontoforese é uma técnica que consiste na administração de drogas para o organismo através dos tecidos, utilizando um campo elétrico. O eletrodo ativo, que se encontra em contato com a droga, é colocado no local a ser tratado, e um segundo eletrodo, com a finalidade de fechar o circuito elétrico, é colocado em outro local do organismo. O campo elétrico facilita o transporte da droga, que deve se encontrar, preferencialmente, na forma ionizada. A iontoforese pode ser considerada como um método seguro e não invasivo de transporte de drogas para locais específicos do olho. Aplicada experimentalmente para o tratamento de doenças oculares, esta técnica tem evoluído muito nos últimos anos e, atualmente, testes clínicos de fase III encontram-se em andamento.