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Matta C.F.,Mount Saint Vincent University | Matta C.F.,Dalhousie University | Matta C.F.,University of Saint Mary
Journal of Computational Chemistry | Year: 2014

The electron density and the electrostatic potential are fundamentally related to the molecular hamiltonian, and hence are the ultimate source of all properties in the ground- and excited-states. The advantages of using molecular descriptors derived from these fundamental scalar fields, both accessible from theory and from experiment, in the formulation of quantitative structure-to-activity and structure-to-property relationships, collectively abbreviated as QSAR, are discussed. A few such descriptors encode for a wide variety of properties including, for example, electronic transition energies, pKa's, rates of ester hydrolysis, NMR chemical shifts, DNA dimers binding energies, π-stacking energies, toxicological indices, cytotoxicities, hepatotoxicities, carcinogenicities, partial molar volumes, partition coefficients (log P), hydrogen bond donor capacities, enzyme-substrate complementarities, bioisosterism, and regularities in the genetic code. Electronic fingerprinting from the topological analysis of the electron density is shown to be comparable and possibly superior to Hammett constants and can be used in conjunction with traditional bulk and liposolubility descriptors to accurately predict biological activities. A new class of descriptors obtained from the quantum theory of atoms in molecules' (QTAIM) localization and delocalization indices and bond properties, cast in matrix format, is shown to quantify transferability and molecular similarity meaningfully. Properties such as "interacting quantum atoms (IQA)" energies which are expressible into an interaction matrix of two body terms (and diagonal one body "self" terms, as IQA energies) can be used in the same manner. The proposed QSAR-type studies based on similarity distances derived from such matrix representatives of molecular structure necessitate extensive investigation before their utility is unequivocally established. © 2014 The Author and the Journal of Computational Chemistry Published by Wiley Periodicals, Inc. The electron density and the electrostatic potential are fundamentally related to the quantum ground state, and hence are the ultimate source of all properties in the ground and excited states. A few descriptors extracted from these fields encode for a staggering variety of observed empirical molecular properties, including electronic transition energies. A new class of descriptors obtained from the quantum theory of atoms in molecules localization and delocalization indices, cast in matrix format, is shown to quantify molecular similarity in structure-to-property relationship-type studies. Copyright © 2014 The Authors Journal of Computational Chemistry Published by Wiley Periodicals, Inc. Source


Qureshi A.,Rawal Institute of Health science | Cozine C.,University of Saint Mary | Rizvi F.,Islamabad Medical and Dental College
American Journal of Physiology - Advances in Physiology Education | Year: 2013

There can be no single best way of learning, and each teaching mode has its own merits and demerits. Didactic lectures in and of themselves are insufficient, whereas a problem-based tutorial alone can be as ineffective. This study was conducted to determine if a problem-based review after didactic lectures would lead to better student performance. To compare performance, the same student group was taught three units of endocrinology (growth hormone, thyroid hormone, and diabetes). Students were divided into the following three groups: diabetes didactic lectures only, growth hormone didactic lectures plus review, and thyroid hormone didactic lectures plus review. All three topics were covered in the didactic lectures, but only growth hormone and thyroid hormone topics were covered in the review session. At the end of the course, all students were given formative assessments in the form of multiple-choice questions. A highly significant increase (P < 0.000) in the percentage of correct responses on the questions covering growth hormone (mean: 0.838, SD: 0.158) and thyroid hormone (mean: 0.686, SD: 0.232) compared with diabetes (mean: 0.478, SD: 0.259) was observed. In conclusion, this study provides further evidence that the combination of didactic lectures and an active review session leads to an improvement in student performance. © 2013 The American Physiological Society. Source


Regarding the mortality causes, esophageal squamous cell carcinoma (ESCC) is on the 7th place in the US and the 6th place in the world, with 5 year overall survival rate of 14%, which is still modest in comparison to other digestive neoplasia. Multiples strategies were involved to improve this percentage, associating surgical procedures and chemo- and radio- oncologic therapies. The distant results showed sensitive improvement, after introduction of multimodality neoadjuvant therapies. Fifty-seven patients diagnosed with ESCC were evaluated between 2006 and 2010, male preponderance (77%), average age of 55. A multimodality therapeutic protocol was used: first - radio-chemotherapy (RCT), second - surgery and/or third - chemo- or radiotherapy. Four weeks post RCT all patients were evaluated to determine the response to neoadjuvant treatment followed by surgery - esophageal resection. Histopathological (HP) and immunohistochemical (IHC) analysis of the pathological specimens were performed in order to identify the molecular predictors with responsive or non responsive character; the studied markers were p53 (Dako 1:50), Ki-67 (Biogenex, 1:20), c-erbB-2 (Dako, 1:250). Based on these results, the working model used to determine the response to neoadjuvant therapy was tumor regression grade (TRG). After HP and IHC examination, the patients were included in two groups: responders and non responders (tumor cells > 10%). Complete neoplasia sterilization was achieved in 5 of the patients. We are able to state that the identification of potential predictive markers along with HP and IHC results represents a great perspective alternative in the ESCC therapy outcome. The detection of molecular type aggressiveness of the neoplastic process allows therapeutic orientation or guidance to certain therapy sequences or even to specific molecular targeted treatments. RevistaChirurgia. Source


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University of Saint Mary | Date: 2010-10-05

Athletic apparel, namely, shirts, pants, jackets, footwear, hats and caps, athletic uniforms.


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Trademark
University of Saint Mary | Date: 2010-10-13

Athletic apparel, namely, shirts, pants, jackets, footwear, hats and caps, athletic uniforms.

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