[Neuronal ceroid lipofuscinosis. Type 6 late infantile variant in two compound heterozygous siblings with novel mutations]. / Lipofuscinosis ceroidea neuronal. Variante infantil tardía de tipo 6 en dos hermanos heterocigotos compuestos con mutaciones nuevas.

INTRODUCTION: There are 14 forms of lipofuscinosis, among them type 6 in its late childhood form is found, it starts between three and eight years with epilepsy, motor disorders, myoclonus, dysarthria, ataxia and neurological regression associated with vision loss and motor skills, and early death. It occurs from mutations in the CLN6 gene, most patients have homozygote variants associated with consanguinity, and rarely, with compound heterozygote variants. CASE REPORT: Siblings, started at 4 and 5 years each, with unstable gear, frequent falls and difficult running. Subsequently, loss of gait, myoclonus, dysphagia, and hallucinations. On physical examination, present optic nerve atrophy, Babinski and trunk ataxia. Electroencephalogram with widespread slow wave bursts during non-REM sleep, non photoparoxystic response, MRI with periventricular white substance hyperintensity, cerebellar atrophy and cortical. Panel of lipofuscinosis report two mutations, c.552del and c.244G>C, not described previously, in both patients. The mother was the carrier of the 552 deletion and the father and paternal grandmother of the G>C substitution (Gly82Arg). CONCLUSIONS: Differential diagnosis in neuroregression disorders is difficult because clinical signs are nonspecific, like many other neurodegenerative disorders with progressive myoclonic epilepsy. We report the clinical findings in two Mexican siblings with the late childhood variant of CLN6 with two new heterozygote mutations that contribute to the knowledge of mutations in the Mexican population and point out the relevance of performing next-generation genetic sequencing studies which will allow a better genetic counseling practice.

TITLE: Lipofuscinosis ceroidea neuronal. Variante infantil tardía de tipo 6 en dos hermanos heterocigotos compuestos con mutaciones nuevas.Introducción. Existen 14 formas de lipofuscinosis. La de tipo 6, en su forma infantil tardía, comienza entre los 3 y 8 años con alteraciones motoras, mioclonos, disartria, ataxia, pérdida de la visión y las habilidades motoras, y muerte temprana. Ocurre por mutaciones en el gen CLN6. La mayoría de los pacientes presenta variantes en estado homocigoto, asociadas a consanguinidad o endogamia, y son poco frecuentes las variantes en estado heterocigoto compuesto. Casos clínicos. Hermanos con síntomas desde los 4 y 5 años, con marcha inestable, caídas frecuentes, posteriormente pérdida de la marcha, mioclonías, disfagia y alucinaciones visuales. En el examen físico presentaban atrofia del nervio óptico, Babinski y ataxia del tronco. El electroencefalograma mostraba brotes de ondas lentas generalizadas, sin respuesta fotoparoxística, y la resonancia magnética de cráneo, hiperintensidad de la sustancia blanca periventricular, y atrofia cerebelosa y cortical. El panel de lipofuscinosis reveló dos mutaciones nuevas en el gen CLN6, c.552del y c.244G>C (p.Gly82Arg), no descritas previamente. La madre resultó portadora de la deleción 552, y el padre y la abuela paterna, de la sustitución G>C (Gly82Arg). Conclusiones. El diagnóstico diferencial en los trastornos con neurorregresión se dificulta debido a que los signos clínicos son inespecíficos, similares a otras epilepsias mioclónicas progresivas. Presentamos los hallazgos clínicos en dos hermanos mexicanos con la variante infantil tardía de CLN6 por dos mutaciones heterocigotas nuevas que contribuyen al conocimiento de las mutaciones en la población mexicana y señalan la relevancia de realizar estudios genéticos aplicando la secuenciación de nueva generación para permitir un adecuado asesoramiento genético.

Lipofuscinosis ceroidea neuronal. Variante infantil tardía de tipo 6 en dos hermanos heterocigotos compuestos con mutaciones nuevas / Neuronal ceroid lipofuscinosis. Type 6 late infantile variant in two compound heterozygous siblings with novel mutations

Introducción: Existen 14 formas de lipofuscinosis. La de tipo 6, en su forma infantil tardía, comienza entre los 3 y 8 años con alteraciones motoras, mioclonos, disartria, ataxia, pérdida de la visión y las habilidades motoras, y muerte temprana. Ocurre por mutaciones en el gen CLN6. La mayoría de los pacientes presenta variantes en estado homocigoto, asociadas a consanguinidad o endogamia, y son poco frecuentes las variantes en estado heterocigoto compuesto. Casos clínicos: Hermanos con síntomas desde los 4 y 5 años, con marcha inestable, caídas frecuentes, posteriormente pérdida de la marcha, mioclonías, disfagia y alucinaciones visuales. En el examen físico presentaban atrofia del nervio óptico, Babinski y ataxia del tronco. El electroencefalograma mostraba brotes de ondas lentas generalizadas, sin respuesta fotoparoxística, y la resonancia magnética de cráneo, hiperintensidad de la sustancia blanca periventricular, y atrofia cerebelosa y cortical. El panel de lipofuscinosis reveló dos mutaciones nuevas en el gen CLN6, c.552del y c.244G>C (p.Gly82Arg), no descritas previamente. La madre resultó portadora de la deleción 552, y el padre y la abuela paterna, de la sustitución G>C (Gly82Arg). Conclusiones: El diagnóstico diferencial en los trastornos con neurorregresión se dificulta debido a que los signos clínicos son inespecíficos, similares a otras epilepsias mioclónicas progresivas. Presentamos los hallazgos clínicos en dos hermanos mexicanos con la variante infantil tardía de CLN6 por dos mutaciones heterocigotas nuevas que contribuyen al conocimiento de las mutaciones en la población mexicana y señalan la relevancia de realizar estudios genéticos aplicando la secuenciación de nueva generación para permitir un adecuado asesoramiento.(AU)

Introduction: There are 14 forms of lipofuscinosis, among them type 6 in its late childhood form is found, it starts between three and eight years with epilepsy, motor disorders, myoclonus, dysarthria, ataxia and neurological regression associated with vision loss and motor skills, and early death. It occurs from mutations in the CLN6 gene, most patients have homozygote variants associated with consanguinity, and rarely, with compound heterozygote variants. Case report: Siblings, started at 4 and 5 years each, with unstable gear, frequent falls and difficult running. Subsequently, loss of gait, myoclonus, dysphagia, and hallucinations. On physical examination, present optic nerve atrophy, Babinski and trunk ataxia. Electroencephalogram with widespread slow wave bursts during non-REM sleep, non photoparoxystic response, MRI with periventricular white substance hyperintensity, cerebellar atrophy and cortical. Panel of lipofuscinosis report two mutations, c.552del and c.244G>C, not described previously, in both patients. The mother was the carrier of the 552 deletion and the father and paternal grandmother of the G>C substitution (Gly82Arg). Conclusions: Differential diagnosis in neuroregression disorders is difficult because clinical signs are nonspecific, like many other neurodegenerative disorders with progressive myoclonic epilepsy. We report the clinical findings in two Mexican siblings with the late childhood variant of CLN6 with two new heterozygote mutations that contribute to the knowledge of mutations in the Mexican population and point out the relevance of performing next-generation genetic sequencing studies which will allow a better genetic counseling practice.(AU)

Surface-enhanced raman spectroscopy: A non invasive alternative procedure for early detection in childhood asthma biomarkers in saliva.

The early detection of bronchial inflammation in asthma, through a non-invasive, simple method and under a subclinical state, could lead to a more effective control of this condition. The aim of this study was to identify biomarkers of bronchial inflammation in the saliva of children with asthma through immunoassay and Surface Enhanced Raman Spectroscopy (SERS). We conducted an analytical cross-sectional study in 44 children ages 6-12; the diagnosis of asthma was made according to Global Initiative for Asthma (GINA) standards. The children's saliva was analyzed by immunoassay for the quantification of 37 cytokines, as well as SERS analysis in a confocal Raman microscope at 785 nm. We found a significant association between bronchial obstruction and IL-8 (p = 0.004), IL-10 (p = 0.008) and sCD163 (p = 0.003). The Raman spectra showed significant amplification in the region of 760 to 1750 cm-1. The Principal Component Analysis and Linear Discriminant Analysis (PCA-LDA) method has a sensitivity of 85%, specificity of 82% and an accuracy of 84% for the diagnosis of asthma. These results demonstrate the presence of a subclinical inflammatory state, suggestive of bronchial remodeling in the population studied. The SERS method is a potential tool for identifying bronchial inflammation and its endotype, allowing for a highly sensitive and specific diagnosis.

Mechanism of ouabain-induced contractions in guinea-pig tracheal rings.

The aim of the present study was to analyse the mechanism that underlies the force development induced by ouabain (ED(100) = 100 micromol/L) in guinea-pig tracheal rings. The dose-response curve showed that concentrations of ouabain above 100 micromol/L evoked smaller contractions. Ouabain, at 100 micromol/L, produced two long-lasting consecutive transient contractions. The peak of the first contraction was 750 +/- 75 mg, whereas the peak of the second contraction was 280 +/- 46 mg. Both contractions induced by ouabain were dependent on extracellular Ca(2+). Consistent with this, verapamil (10 micromol/L) inhibited the first and second contractions by 77 and 59%, respectively. 3,4-Dichlorobenzamil (20 micromol/L) inhibited the first and second contractions by 68 and 97%, respectively. Simultaneous exposure to 15 mmol/L sodium solution and 100 micromol/L ouabain evoked only one transient contraction, larger (987 +/- 135 mg) than either of the ouabain-induced contractions. Inhibition of the sarcoendoplasmic reticulum Ca-ATPase with cyclopiazonic acid potentiated the first and second ouabain-induced contractions by 47 and 300%, respectively. Atropine (1 micromol/L) inhibited the first and second contractions by 44 and 76%, respectively. In conclusion, the results of the present study are relevant to the understanding of the mechanisms by which ouabain (100 micromol/L) contracts guinea-pig tracheal rings. At the muscular level, oubain induces Ca(2+) influx through L-type Ca(2+) channels and the reverse mode of the sodium-calcium exchanger. At the nerve terminals, ouabain promotes the release of acetylcholine secondary to the increase in Ca(2+) influx mediated by the reverse mode of the sodium-calcium exchanger.

[Ca2+]i changes in guinea pig tracheal smooth muscle cells in culture: effects of Na+ and ouabain.

The objective of this work was to confirm that the contractile effects of ouabain and Na(+)-free solutions in guinea pig tracheal rings are associated with increments in the cytosolic free Ca2+ concentration ([Ca2+]i) in cultured tracheal smooth muscle (TSM) cells. Cultured cells were alpha-actin positive. Histamine (50 microM) and Na(+)-free solution elicited a transient increase in [Ca2+]i, while the responses to thapsigargin (1 microM) and ouabain (1 mM) were long lasting. However, carbachol (10, 200, and 500 mM) and high K(+)-solution produced no effect on [Ca2+]i, suggesting that cultured guinea pig TSM cells display a phenotype change but maintain some of the tracheal rings physiological properties. The transient rise in [Ca2+]i in response to the absence of extracellular Na+ and the effect of ouabain may indicate the participation of the Na(+)/Ca2+ exchanger (NCX) in the regulation of [Ca2+]i.

Alpha-chymotrypsin deregulation of the sodium-calcium exchanger in barnacle muscle cells.

To gain insight into the mechanism by which the protease alpha-chymotrypsin (alpha-chym) activates the Na-Ca exchanger in muscle cells we studied 1) the ability of this enzyme to remove the intracellular "catalytic" Ca2+ requirement for activation of all the modes of exchange mediated by the Na-Ca exchanger (i.e., Nao-Cai, Nai-Cao, Nao-Nai, and Cao-Cai, where the subscripts o and i represent extracellular and intracellular, respectively), and 2) the ability of certain monovalent cations to stimulate Cao-Cai exchange after activation of the exchanger by alpha-chym. Barnacle muscle cells were used as models because these cells are so large that they can be internally perfused and voltage clamped. The results show that alpha-chym produces a highly activated Na-Ca exchanger able to operate in all its modes of exchange independently of catalytic Cai. The concentration-dependent effect of alpha-chym was biphasic; maximal activation occurred at 0.5 mg alpha-chym/ml perfusate for 20 min of perfusion at a perfusion rate of 2.5 microliters/min. The results are discussed in terms of the possible effects of alpha-chym on the kinetic modulation of the exchanger.