Encapsulation of Lactobacillus plantarum ATCC 8014 and Pediococcus acidilactici ATCC 8042 in a freeze-dried alginate-gum arabic system and its in vitro testing under gastrointestinal conditions.

The aim of this study was to investigate the viability of Pediococcus acidilactici ATCC 8042 and Lactobacillus plantarum ATCC 8014 in a freeze-dried capsules system prepared with sodium alginate and gum arabic using the extrusion technique. The capsules made with alginate 2% (w/v)/gum arabic 2% (w/v) showed higher hardness (7.12 ± 0.71 N), with highly cohesive (0.81 ± 0.02) and elastic (0.99 ± 0.00) features on the Texture Profile Analysis (TPA), as well as higher sphericity with 1.75 ± 0.12 mm y 1.73 ± 0.13 mm diameter axes and regularity in their surface by Scanning Electron Microscopy (SEM). The use of skimmed milk at 10% as a cryoprotector in the freeze-drying process allowed the obtention of high viability percentages (88% a 96%) for both strains. Best results of viability for P. acidilactici encapsulated was with the use of alginate 2% (w/v)/gum arabic 2% (w/v) (92%±2.65), and L. plantarum with the use of alginate 2% (w/v) (84.71%±10.33) during the gastrointestinal environment challenge.

Síndrome de Leigh causado por la mutación G14459A del ADN mitocondrial en una familia mexicana / Leigh syndrome caused by the mitochondrial DNA G14459A mutation in a mexican family

Introducción. El síndrome de Leigh es una enfermedad neurodegenerativa y progresiva, de aparición en la infancia, que está causada por defectos tanto en el genoma nuclear como en el mitocondrial. La mutación G14459A del ADN mitocondrial se ha asociado con anterioridad a la neuropatía óptica hereditaria de Leber y recientemente al síndrome de Leigh. Caso clínico. Niña mexicana de 10 meses de edad diagnosticada, después de un seguimiento clínico, neurológico y radiológico, de síndrome de Leigh. Se le realizó el análisis de mutaciones puntuales en el ADN mitocondrial asociadas a este síndrome, y se encontró la mutación G14459A en un porcentaje próximo a la homoplasmia y en heteroplasmia en la madre. El resto de familiares relacionados por vía materna carecen de la mutación. Conclusión. La mutación G14459A, aunque poco frecuente en la patología, debe de estudiarse en pacientes con síndrome de Leigh que no presentan las mutaciones puntuales más comunes (AU)

Introduction. Leigh syndrome is a neurodegenerative and progressive disease that appears usually in childhood due to defects in nuclear or mitochondrial genome. The mutation G14459A in mitochondrial DNA has been associated previously to Leber hereditary optic neuropathy and recently to Leigh syndrome. Case report. A 10 months-old Mexican girl diagnosed of Leigh syndrome. Molecular-genetic studies detected the mutation G14459A in a percentage close to homoplasmy and in low heteroplasmy in her mother. The rest of the maternally related family members analyzed were negative. Conclusion. The G14459A mutation, although not very frequently associated to Leigh syndrome, should be analyzed in patients that do not present the most common point mutations (AU)

[Leigh syndrome caused by the mitochondrial DNA G14459A mutation in a Mexican family]. / Síndrome de Leigh causado por la mutación G14459A del ADN mitocondrial en una familia mexicana.

INTRODUCTION: Leigh syndrome is a neurodegenerative and progressive disease that appears usually in childhood due to defects in nuclear or mitochondrial genome. The mutation G14459A in mitochondrial DNA has been associated previously to Leber hereditary optic neuropathy and recently to Leigh syndrome. CASE REPORT: A 10 months-old Mexican girl diagnosed of Leigh syndrome. Molecular-genetic studies detected the mutation G14459A in a percentage close to homoplasmy and in low heteroplasmy in her mother. The rest of the maternally related family members analyzed were negative. CONCLUSION: The G14459A mutation, although not very frequently associated to Leigh syndrome, should be analyzed in patients that do not present the most common point mutations.

[Mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) with the A3243G mutation of the tRNALeu(UUR) gene of mtDNA in native American haplogroup B2]. / Encefalomiopatía mitocondrial, acidosis láctica y accidentes cerebrovasculares (MELAS) con la mutación A3243G en el gen ARNtLeu(UUR) del ADNmt en el haplogrupo B2 nativo americano.

INTRODUCTION: Mitochondrial encephalopathy, lactic acidosis and cerebrovascular accident syndrome (MELAS) is, from the clinical point of view, one of the best studied mitochondrial multisystemic disorders. This disease has mainly been associated to the mitochondrial desoxyribonucleic acid (mtDNA) mutation A3243G located in the tRNALeu(UUR) gene. Although a relation between European haplogroups and the presence of the 3243 mutation has not been described, nothing is known about the presence of this mutation in native American haplogroups. CASE REPORT: A 12 year-old female Mexican patient diagnosed with MELAS is reported. Besides neurological, biochemical and cytological examination, we also analyzed the particular mtDNA mutations related to MELAS and the whole genome was sequenced to determine the mitochondrial haplogroup. The A3243G mutation was detected in the patient and maternal relatives (mother and siblings, all of them asymptomatic). The genotype corresponds to the native American haplogroup B2 and contains two private non-synonymous polymorfisms. CONCLUSION: All the members of the family studied present different percentage of the A3243G mutation, being the patient who presented the highest value. The mtDNA genotype corresponds to the native American haplogroup B2 and the private polymorphisms do not confer any phenotypic modification in MELAS syndrome.

Direct and highly species-specific detection of pork meat and fat in meat products by PCR amplification of mitochondrial DNA.

Highly species-specific primers for pork D-loop mtDNA have been designed. Use of these and restrictive PCR amplification conditions has improved a reliable and rapid method for detecting a PCR-amplified 531 bp band from pork. It has been proved useful for detecting both pork meat and fat in meat mixtures, including those dry-cured and heated by cooking. Absence of response in PCR-amplified samples or mixtures from bovine, ovine, chicken, and human was also demonstrated. Furthermore, wild boar and pork samples can be also easily distinguished by a simple AvaII restriction analysis.