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We propose a general framework to solve tight binding models in D dimensional lattices driven by ac electric fields. Our method is valid for arbitrary driving regimes and allows us to obtain effective Hamiltonians for different external field configurations. We establish an equivalence with time-independent lattices in D+1 dimensions and analyze their topological properties. Furthermore, we demonstrate that nonadiabaticity drives a transition from topological invariants defined in D+1 to D dimensions. Our results have potential applications in topological states of matter and nonadiabatic topological quantum computation, predicting novel outcomes for future experiments.

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OBJECTIVE: Evaluate the presence and severity of myocardial ischaemia in a population of asymptomatic patients with primary APS (PAPS) using (13)N-ammonia PET. METHODS: We studied 36 patients, 18 with a diagnosis of PAPS and 18 healthy volunteers. All patients underwent a two-phase (rest-stress) (13)N-ammonia PET. Myocardial perfusion images were acquired and then analysed by two experts in the field. RESULTS: We found ischaemia in 7/18 asymptomatic PAPS patients (38.8%). The anterolateral wall was the most commonly affected cardiac territory [5/7 PAPS patients (71.4%)]. In a severity analysis, we found that five patients (71.4%) had mild ischaemia, one patient (14.2%) had moderate ischaemia and another one (14.2%) had severe defects. All the healthy volunteers studied showed normal myocardial perfusion images. CONCLUSION: An important proportion of PAPS patients, even when asymptomatic, showed myocardial perfusion defects assessed with PET. Most of the ischaemic patients had mild defects and the anterolateral wall was the territory mainly affected.

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Non-insulin-dependent diabetes mellitus (NIDDM) is the most common form of diabetes, affecting 5% of the general population. Genetic factors play an important role in the development of the disease. While in other populations NIDDM is usually diagnosed after the fifth decade of life, in Mexico a large proportion of patients develop the disease at an early age (between the third and the fourth decade). In Caucasian population, mutations in the glucokinase gene, the TCF1, and TCF14 genes, have been identified in a subgroup of early-onset NIDDM patients denominated MODY (maturity-onset diabetes of the young), which show an autosomal dominant pattern of inheritance. As a first step in the molecular characterization of Mexican families displaying early-onset NIDDM we searched for mutations in the glucokinase gene through SSCP analysis and/or direct sequencing in 26 individuals from 22 independent families, where at least four can be classified as MODY. No mutations were detected in the exons or the intron-exon boundaries of the gene in any of the screened individuals. The phenotype and clinical profile of some of the studied patients is compatible with that of patients carrying mutations in the TCF1 or TCF14 genes, while others may carry mutations in different loci. Through computer simulation analysis we identified at least four informative families which will be used for further linkage studies.

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A study was made of 48 patients from the different departments of the Hospital del Niño, DIF, in which hookworm eggs were demonstrated by qualitative coproparasitoscopic study (CPS). During the study, quantitative CPS was practiced on them by Stoll's dilution and the Harada-Mori technique, for the identification of the hookworm larvae. They were divided into three groups: A, B and C (16 patients in each group); the study was single-blind. The effectiveness of the evaluated drugs was based on the disappearance or diminution of hookworms eggs in the CPS (Stoll) practiced 2 weeks after the drug treatment had finished. The work was done with patients parasitized by Necator americanus (verified by the Harada-Mori technique). The A group was given pyrantel pamoate; the B group, thiabendazole and the C group, mebendazole. The results obtained were statistically processed by means of X2 proportions. There was no significant difference between the three groups when a light to moderate necatoriasis was treated; when a massive infection was involved, there was a significant difference and it was found that the best drug was pyrantel pamoate administered at the dose of 20 mg/kg/day/3 days. There were few side effects in the three groups, but they were not sufficient to cause suspension of the treatment. The cheapest drug was thiabendazole.

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