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Mexico City, Mexico

Martinez-Castro J.,National Polytechnic Institute of Mexico | Reyes-Cadena S.,Instituto Nacional De | Felipe-Riveron E.,National Polytechnic Institute of Mexico
Revista Mexicana de Ingenieria Biomedica | Year: 2014

Using the κ-NN classifier in combination with the first Minkowski metric, in addition to techniques of digital image processing, we developed a computational system platform-independent, which is able to identify, to classify and to count five normal types of leukocytes: neutrophils, eosinophils, basophils, monocytes and lymphocytes. It is important to emphasize that this work does not attempt to differentiate between smears of leukocytes coming from healthy and sick people; this is because most diseases produce a change in the differential count of leukocytes rather than in theirs forms. In the other side, the system could be used in emerging areas such as the topographic hematology and the chronobiology. Source

This paper presents an analysis of the foraging behavior and interactions of Xylocopa frontalis Olivier (Apidae: Xylocopini) and Eulaema mocsaryi (Friese) (Apidae: Euglossini) in the presence of stingless bees (Apidae: Meliponini) in flowers of Bertholletia excelsa, the Brazilian nut. The palynological load carried by both species was also examined. This study was conducted in the farm Aruanã, Itacoatiara/ Amazonas state, Brazil, during the flowering peak of B. excelsa. The visitation by the main pollinators X. frontalis and E. mocsaryi were influenced by the presence and activities of stingless bees in the flowers of B. excelsa. Meliponini bees did not have any effect on the visits and collection of fl oral resources by X. frontalis, while negatively affecting the number of visits by E. mocsaryi. The stingless bees presented a variety of strategies to get access to pollen grains of B. excelsa, grouped into two categories: opportunism - Frieseomelitta trichocerata Moure, Tetragona goettei (Friese), and Tetragona kaieteurensis (Schwarz), and stealing - Trigona branneri Cockerell, Trigona fuscipennis Friese, and Trigona guianae Cockerell. The palynological analysis from X. frontalis showed that the bee collected pollen in a few species of plants, but mainly on B. excelsa. The pollen grains of B. excelsa were poorly represented in the pollen shipments of E. mocsaryi, due to its large trophic niche in the locality. Source

Montano M.,Instituto Nacional De | Cisneros J.,Instituto Nacional De | Ramirez-Venegas A.,Instituto Nacional De | Mercado D.,Instituto Nacional De | And 2 more authors.
Inhalation Toxicology | Year: 2010

Tobacco smoking is the primary risk factor for chronic obstructive pulmonary disease (COPD). However, recent epidemiological studies have established domestic exposure to wood smoke and other biomass fuels as additional important risk factors, characteristic in developing countries. Oxidative stress is one of the mechanisms concerned with pathogenesis of COPD. However, the molecular mechanisms involved in the onset and progress of COPD associated with biomass and specifically that derived from wood smoke exposure remain unknown. We analyzed the relationship between forced expiratory volume in first second (FEV1) with plasma malondialdehyde (MDA) concentration and activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione-S-transferase (GST) in COPD patients associated with wood smoke (WSG; n30), tobacco smoking (TSG; n30), and healthy control subjects (HCG; n30). Differences between FEV1 from WSG and TSG (58±22% and 51±24%, respectively) with HCG (100±6%) were observed (P < 0.01). Plasma MDA concentration was higher in both WSG and TSG (1.87±0.81 and 1.68±0.82 nmol/mL, respectively) compared with HCG (0.42±0.17 nmol/mL; P<0.01). SOD activity showed a significant increase in both WSG and TSG (0.36±0.12 and 0.37±0.13U/mL) compared with HCG (0.19±0.04U/mL; P<0.01). No differences were shown regarding GPx, GR, and GST activities between COPD and control groups. Inverse correlations were founded between MDA and SOD with FEV1 in both COPD patients and control subjects (P<0.001). These results indicate a role for oxidative stress in COPD associated with wood smoke similar to that observed with tobacco smoking in subjects who ceased at least 10 years previous to this study. © 2010 Informa Healthcare USA, Inc. Source

Castiglioni C.,Instituto Nacional De | Levican J.,Clinica Las Condes | Garmendia M.A.,Clinica Las Condes | Diaz A.,Instituto Nacional De | Contreras L.,Clinica Las Condes
Revista Medica de Chile | Year: 2011

Background: Spinal Muscular Atrophy (SMA) is an autosomal recessive disorder affecting the anterior horn cells of the spinal cord resulting in muscle weakness and atrophy, linked to the homozygous disruption of the survival motor neuron 1 (SMN1) gene. It is the leading genetic cause of infant death. It has been classified into three types based on the severity of symptoms. Type I SMA is the most severe form with death within the first 2 years of life. Type II and III SMA patients show intermediate and mild forms of the disorder. Aim: To describe the clinical and electrophysiological findings of 26 Chilean patients with SMA with molecular confirmation. Patients and Methods: Retrospective multicenter analysis of patients with SMA assessed between 2003 and 2010. The diagnosis was suspected on clinical and electrophysiological criteria. Since 2006 molecular genetics confirmation was implemented in one of our centers. Results: Twenty-six patients between 2 months and 18 years of age at presentation were analyzed; 15 (58%) were males. SMA I, II and III clinical criteria were observed in 4 (15.4 %), 11(42.3%) and 11(42.3%) patients, respectively. All had proximal muscle weakness and atrophy. Electromyography showed features of acute denervation or re-innervation with normal motor and sensory nerve conduction. Nine patients required a muscle biopsy. The genetic confirmation of the disease by PCR technique followed by restriction fragment length polymorphism method disclosed the SMN1 gene deletion in all 26 cases. All patients died secondary to respiratory failure, between eight and 14 months of life. Conclusions: An adequate clinical and molecular diagnosis of spinal muscular atrophy will help for a better management of these patients. Source

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