Diferença de potencial nasal: um novo teste para diagnóstico de fibrose cística / Nasal potential difference: a new test for cystic fibrosis diagnosis

Introdução: Fibrose Cística (FC) é uma doença cujo diagnóstico é essencialmente clínico, confirmada por dosagem de cloro no suor acima de 60 mEq/L e/ou identificação das mutações do CFTR causadoras da doença nos dois alelos. Casos atípicos necessitam ser investigados através do exame da diferença de potencial nasal (DPN). Na FC a DPN é mais negativa, há maior despolarização com o amiloride e pouca resposta ao isoproterenol. Objetivo: Determinar os valores da DPN para portadores de FC e grupos controle. Métodos: A DPN foi medida em 24 portadores de FC, 19 portadores de outras doenças não FC e 18 sadios e foram determinadas a média e desvio-padrão da DPN máxima, 8 amil, 8ØCl, 8iso, 8Cl, 8amil+iso e index DPN. Resultados: A média da DPN máxima foi -32 mV no grupo FC, -14 mV no grupo Não FC e -16 mV no grupo Sadio (P<0,0001). No grupo FC a média do 8 amil foi -18 mV, no grupo Não FC -6 mV e no grupo Sadio -7mV (P<0,0001). No grupo FC a média do 8Cl foi 4mV, 17mV no grupo Não FC e 11mV no grupo Sadio. A média do index 8 amil + iso foi - 16mV e o index DPN foi 0,85 no grupo FC, comparado com -0,6 mV e 0,26 no grupo Não FC e -2mV e 0,23 no grupo Sadio. Conclusões: O teste da DPN pode claramente diferenciar o grupo FC, com valores semelhantes aos descritos na literatura, possibilitando seu emprego futuro como teste diagnóstico complementar nos casos atípicos de FC.

Cystic Fibrosis (CF) is a disease whose diagnosis is essentially clinical, confirmed by measurement of sweatchloride above 60mEq / L and / or identification of CFTR mutations that cause disease in two alleles. Atypical cases need to be investigated by the nasal potential difference test (NPD). In CF the NPD is more negative, there is increased depolarization with amiloride (Eamil ) and a poor response to the isoproterenol (Eiso). Aim: To determine the values of NPD for CF patients and control groups. Methods: DPN was measured in 24 CF patients, 19 carriers of other diseases non-CF and 18 healthy and the mean plus standard deviation of NPD maximum, E amyl, EØCl, Eiso, ECl, E amil+iso and index NPD were determined. Results: NPD maximum in the FC group was -32 mV, -14 mV In the non-CF and-16mV in healthy group (p <0.0001). In the CF group the mean Eamil was - 18mV, -6mV in the non-FC group and -7mV in healthy (p <0.0001). The ECl mean was 4mV in CF group, 17mV in non-CF and 11mV in healthy. The average of the index E amil+iso was-16mV and DPN index was 0.85 in FC group compared with -0.6 mV and 0.26 in non-CF and -2mV, and 0.23 in healthy. Conclusions: The test of DPN can clearly distinguish the CF group, with values similar to those described in the literature, enabling their future use as a complementary diagnostic test in atypical cases of CF.

Fibrosis quística: aspectos diagnósticos / Cystic fibrosis: diagnosis

La fibrosis quística (FQ) es una de las enfermedades genéticas mortales más frecuentes en la raza caucásica. Se caracteriza por una disfunción de las glándulas exocrinas, con insuficiencia pancreática y bronconeumopatía crónica. Es una enfermedad de transmisión autonómica recesiva, se sabe que el gen defectuoso está localizado en el cromosoma 7 humano, conocido como gen regulador de la conductancia transmembrana de la fibrosis quística (CFTR),y que de las más de mil mutaciones de este gen, la mutación DF508 es la más común, pues se halla en aproximadamente 70% de los alelos CFTR defectuosos. El diagnóstico de la FQ se ha basado clásicamente en la determinación de por lo menos 2-3 determinaciones positivas de electrólitos en sudor, junto con uno de los siguientes criterios clínicos: íleo meconial, historia familiar de FQ, insuficiencia pancreática exocrina, enfermedad pulmonar crónica, azoospermia obstructiva y síndrome de pérdida de sal. Los criterios diagnósticos actuales incluyen, junto a la presencia de las características clínicas, dos determinaciones de concentraciones de cloro en sudor superior a 60 mmol/l, o demostración de alteraciones en el transporte iónico a través del epitelio nasal (diferencia de potencial nasal) o la detección de dos mutaciones reconocidas de FQ.

Cystic fibrosis (CF) is one of the most frequent inherited mortal diseases in Caucasian population. Dysfunction in exocrine glands is described in CF patients, with severe pancreatic insufficiency and chronic lung disease. CF is inherited as an autosomal recessive disorder. More than 1000 disease-associated mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene have been described. DF508 mutation is the most common mutation in the CF gen. Diagnosis in CF is based on clinical and laboratory tests findings. Meconial ileus, CF in other relatives, chronic lung disease, congenital absence of the vas deferens with azoospermia are among other clinical findings, main criteria in CF patients. Two positive results in sweat chloride test , or demonstration in nasal epithelial ionic transport alteration (nasal potential difference) and identification of two CF mutations in the patient are laboratory findings in CF.

Effect and mechanism of emodin on intestinal movement / 中国药理学通报

AIM To examine the effect and mechanism of emodin on intestinal movement of constipation model. METHODS The movement of charcoal powder and the absorption of D-xylose into serum were observed. The electrical p otential difference(PD) related to Na + and glucose transport was measured across the wall of rev erted intestinal sacs. RESULTS Emodin 0 1, 0 2 g?kg -1 incr eased markedly the rate of charcoal powder moving and inhibited the absorption of D-xylose into serum. Emodin 0 2, 0 4, 0 8 and 1 6 g?L -1 decreased PD when ther e was glucose. However, emodin had little effect when glucose was free. CONCLUSION Emodin promotes intestinal movement and this effect is related to Na +,K +-ATPase.

Measurement of Transendothelial Potential Difference to Evaluate the Chondroitin Sulfate Effect in TC-l99 Cornea Preservation Media

Chondroitin sulfate (CS) in corneal preservation medium can porolong corneal preservation time. The solutions used in the experimental chambers were made of TC-199 (GIB Co.) either by itself of by adding 1% CS (Sigma) to the TC-199. The evaliation of the viability of corneas can be made by monitoring their physiological parameter. Thus, we monitored the transendothelial electrical potential difference (p.d.) across deepithelialized rabbit corneas. We found that TC-199 containing 1% CS maintained higher p.d.'s than the same solution without CS.

Chondroitin sulfate in Corneal Preaervation Media Assessed by monitoring the Transendothelial Electrical Potential Difference

Recently a great deal of attention has been focused on increasing corneal preservation time, and chondroitin sulfate in corneal preservation media can prolong corneal preservation time. So far evaluation of the effectiveness of this and some additives have been based on determining the state of the cornea at the end of the preservation period. We have accomplished this by monitoring in vitro the transendothelial electrical potential difference across deepithelialized rabbit cornea. We found that corneas stored in basal salt plus glucose containing chondroitin sulfate maintained higher transendothelial potential difference than corneas stored in the same solutions without chondroitin sulfate. The beneficial effects of chondroitin sulfate were opthimal at the 1% concentration.

The effect of total glycoside of Rhubarb, Emodin and Sennosides on transmural potential of mouse intestine in vitro / 中国药理学通报

The electrical potential difference (PD) was measured across the wall of reverted intestinal sacs. The effect of the effective component of Rhubarb on transmural potential related to Na+ and glucose transport were investigated. It was found that total glucoside of Rhubarb, Emodin and Sen-nosides decreased the PD. The experimental resuilts provide new scientific basis for explaining the mechanism of Rhubarb's purgative action.