Further insights in trichothiodistrophy: a clinical, microscopic, and ultrastructural study of 20 cases and literature review

Background: Trichothiodistrophy (TTD) is a rare autosomal recessive condition that is characterized by a specific congenital hair shaft dysplasia caused by deficiency of sulfur associated with a wide spectrum of multisystem abnormalities. In this article, we study clinical, microscopic, and ultrastructural findings of 20 patients with TTD with the aim to add further insights regarding to this rare condition. Additionally, analyses of our results are compared with those extracted from the literature in order to enhance its comprehensibility. Materials and Methods: Twenty cases of TTD were included: 7 from Mexico and 14 from Spain. Clinical, microscopic, scanning electron microscopy (SEM) studies and X-ray microanalysis (XrMa) were carried out in all of them. Genetic studies were performed in all seven Mexican cases. Patients with xeroderma pigmentosum and xeroderma pigmentosum/TTD-complex were excluded. Results: Cuticular changes and longitudinal crests of the hair shaft were demonstrated. These crests were irregular, disorganized, following the hair longest axis. Hair shaft sulfur deficiency was disposed discontinuously and intermittently rather than uniformly. This severe decrease of sulfur contents was located close to the trichoschisis areas. Only five patients did not show related disturbances. Micro-dolichocephaly was observed in five cases and represented the most frequent facial dysmorphism found. It is also remarkable that all patients with urologic malformations also combined diverse neurologic disorders. Moreover, three Mexican sisters demonstrated the coexistence of scarce pubic vellus hair, developmental delay, onychodystrophy, and maxillar/mandibullar hypoplasia. Conclusions: TTD phenotype has greatly varied from very subtle forms to severe alterations such as neurologic abnormalities, blindness, lamellar ichthyosis and gonadal malformations. Herein, a multisystem study should be performed mandatorily in patients diagnosed with TTD

Further insights in trichothiodistrophy: A clinical, microscopic, and ultrastructural study of 20 cases and literature review

Trichothiodistrophy (TTD) is a rare autosomal recessive condition that is characterized by a specific congenital hair shaft dysplasia caused by deficiency of sulfur associated with a wide spectrum of multisystem abnormalities. In this article, we study clinical, microscopic, and ultrastructural findings of 20 patients with TTD with the aim to add further insights regarding to this rare condition. Additionally, analyses of our results are compared with those extracted from the literature in order to enhance its comprehensibility. Materials and Methods: Twenty cases of TTD were included: 7 from Mexico and 14 from Spain. Clinical, microscopic, scanning electron microscopy (SEM) studies and X-ray microanalysis (XrMa) were carried out in all of them. Genetic studies were performed in all seven Mexican cases. Patients with xeroderma pigmentosum and xeroderma pigmentosum/TTD-complex were excluded. Results: Cuticular changes and longitudinal crests of the hair shaft were demonstrated. These crests were irregular, disorganized, following the hair longest axis. Hair shaft sulfur deficiency was disposed discontinuously and intermittently rather than uniformly. This severe decrease of sulfur contents was located close to the trichoschisis areas. Only five patients did not show related disturbances. Micro-dolichocephaly was observed in five cases and represented the most frequent facial dysmorphism found. It is also remarkable that all patients with urologic malformations also combined diverse neurologic disorders. Moreover, three Mexican sisters demonstrated the coexistence of scarce pubic vellus hair, developmental delay, onychodystrophy, and maxillar/mandibullar hypoplasia. Conclusions: TTD phenotype has greatly varied from very subtle forms to severe alterations such as neurologic abnormalities, blindness, lamellar ichthyosis and gonadal malformations. Herein, a multisystem study should be performed mandatorily in patients diagnosed with TTD

Interelectrode Distance Analysis in the Water Defluoridation by Electrocoagulation Reactor

In this research, the effect of the interelectrode distance (d) in the electrocoagulation (EC) reactor was studied. The experiments were carried out with varying d in values of 3, 5, and 9 mm during the treatment of water contaminated with fluoride (F−). The response variables analyzed were the treatment time necessary to reduce the residual concentration of F− to 1.5 mg L−1, the number of aluminum hydroxides formed, the potential drop in the reactor terminals, and the electric power consumption of the reactor. The software FLUENT version 6.3 was employed to simulate the liquid velocity profiles achieved in the reactor chamber. The results obtained show that the liquid velocity increases in the interelectrode spaces to 0.48, 0.65, and 0.86 m s−1 for interelectrode distances of 9, 5, and 3 mm, respectively, which favors not only the formation of flocs but also the elimination of fluoride. With a shorter interelectrode distance, the EC reactor not only consumes less electrical energy but also fewer electrodes, and the dispersion of generated flocs in the reactor chamber is major, which is more important than the quantity of flocs generated in it

Interelectrode Distance Analysis in the Water Defluoridation by Electrocoagulation Reactor

In this research, the effect of the interelectrode distance (d) in the electrocoagulation (EC) reactor was studied. The experiments were carried out with varying d in values of 3, 5, and 9 mm during the treatment of water contaminated with fluoride (F−). The response variables analyzed were the treatment time necessary to reduce the residual concentration of F− to 1.5 mg L−1, the number of aluminum hydroxides formed, the potential drop in the reactor terminals, and the electric power consumption of the reactor. The software FLUENT version 6.3 was employed to simulate the liquid velocity profiles achieved in the reactor chamber. The results obtained show that the liquid velocity increases in the interelectrode spaces to 0.48, 0.65, and 0.86 m s−1 for interelectrode distances of 9, 5, and 3 mm, respectively, which favors not only the formation of flocs but also the elimination of fluoride. With a shorter interelectrode distance, the EC reactor not only consumes less electrical energy but also fewer electrodes, and the dispersion of generated flocs in the reactor chamber is major, which is more important than the quantity of flocs generated in it

II. Conflictos entre felinos y humanos en América Latina.

Este libro contó con el liderazgo del Instituto Humboldt y de las Fundaciones Herencia Ambiental Caribe y Panthera. En 32 capítulos se recoge el esfuerzo de 77 instituciones y 110 autores que representan 18 países y abordan el conflicto entre humanos y felinos en América Latina. Es la compilación más completa que se ha elaborado acerca del tema en Latinoamérica, involucrando el análisis, la planificación, el manejo y la resolución de los conflictos entre humanos y felinos.BogotáCiencias de la Biodiversida