Aleksandra Malgorzata Urbanska

Bio: Aleksandra Malgorzata Urbanska is an academic researcher from McGill University. The author has contributed to research in topics: Lactobacillus fermentum & Lactobacillus acidophilus. The author has an hindex of 18, co-authored 23 publications receiving 961 citations.

Erratum of “Investigation of Microencapsulated BSH Active Lactobacillus in the Simulated Human GI Tract”

Abstract: This is to confirm that there is an error in the article “Investigation of Microencapsulated BSH Active Lactobacillus in the Simulated Human GI Tract” by Martoni et al. Published online December 25, 2007, doi: 10.1155/2007/13684. Figure 5 should be replaced by Figure 5 below. Figure 5 Evaluation of microcapsule integrity and morphological changes during simulated GI transit. (a) Pre-stomach transit (b) Post-stomach transit (60 minutes) (c) Post-stomach (60 minutes) and intestinal (10 hours) transit.Microcapsule size (a) 608 ± ...

Investigation of microencapsulated BSH active lactobacillus in the simulated human GI tract.

Abstract: This study investigated the use of microencapsulated bile salt hydrolase (BSH) overproducing Lactobacillus plantarum 80 cells for oral delivery applications using a dynamic computer-controlled model simulating the human gastrointestinal (GI) tract Bile salt deconjugation rates for microencapsulated BSH overproducing cells were 487 ± 028 μmol/g microcapsule/h towards glycoconjugates and 079 ± 015 μmol/g microcapsule/h towards tauroconjugates in the simulated intestine, a significant (P< 05) increase over microencapsulated wild-type cells Microcapsules protected the encased cells in the simulated stomach prior to intestinal release, maintaining cell viability above 109 cfu/mL at pH 25 and 30 and above 106 cfu/mL at pH 20 after 2-hour residence times In the simulated intestine, encased cell viability was maintained above 1010 cfu/mL after 3, 6, and 12-hour residence times in bile concentrations up to 10% Results show that microencapsulation has potential in the oral delivery of live BSH active bacterial cells However, in vivo testing is required

In vitro study of alginate-chitosan microcapsules : an alternative to liver cell transplants for the treatment of liver failure

Abstract: The application of alginate–chitosan (AC) microcapsules to liver cell transplantation has not been previously investigated. In the current in vitro study, we have investigated the potential of AC microcapsules for the encapsulation of liver cells and show that the AC membrane supports the survival, proliferation and protein secretion by entrapped hepatocytes. The AC membrane provides cell immuno-isolation and has the potential for cell cryopreservation. The AC microcapsule has several advantages compared to more widely used alginate–poly-L-lysine (APA) microcapsules for the application of cell therapy.

Estimation of the potential antitumor activity of microencapsulated Lactobacillus acidophilus yogurt formulation in the attenuation of tumorigenesis in Apc(Min/+) mice.

Abstract: There is a strong correlation between orally administered probiotics and suppression of the low-grade inflammation that can lead to restoration of normal local immune functions. We studied the potential immunomodulatory and antitumorigenic properties of microencapsulated probiotic bacterial cells in a yogurt formulation in Min mice carrying a germline APC mutation. Daily oral administration of microencapsulated Lactobacillus acidophilus bacterial cells in the yogurt formulation mice resulted in significant suppression of colon tumor incidence, tumor multiplicity, and reduced tumor size. Results show that oral administration of microencapsulated L. acidophilus contributed to the stabilization of animal body weight and decreased the release of bile acids. Histopathological analyses revealed fewer adenomas in treated versus untreated animals. Furthermore, treated animals exhibited fewer gastrointestinal intra-epithelial neoplasias with a lower grade of dysplasia in detected tumors. Results suggest that oral administration of microencapsulated probiotic L. acidophilus exerts anti-tumorous activity, which consequently leads to reduced tumor outcome.

Orally delivered microencapsulated live probiotic formulation lowers serum lipids in hypercholesterolemic hamsters.

Abstract: Elevated serum cholesterol is a major risk factor for coronary artery disease. Nutritional therapies such as probiotics have been suggested to manage elevated cholesterol. This study investigates the cholesterol and triglyceride lowering potential of a microencapsulated feruloyl esterase-producing Lactobacillus fermentum 11976 (LF11976) probiotic formulation. Male Bio F(1)B hamsters were assigned to two groups to receive either the microcapsule probiotic formulation (containing LF11976 cells at 12.51 log colony-forming units/mL) or placebo formulation (empty) microcapsules, twice daily, by oral gavage for 18 weeks. For the duration of the study, animals were fed a hypercholesterolemic diet. Serum total cholesterol, low-density lipoprotein (LDL) cholesterol, and the atherogenic index were 21.36%, 31.43%, and 32.59% lower in the group gavaged with the microencapsulated probiotic formulation than in the placebo control group after 18 weeks (P < .05). Histology studies showed reduced progression of atherosclerotic lesions in animals treated with microencapsulated LF11976 as compared to control animals. Treatment with microencapsulated LF11976 formulation produces significant reductions in serum total cholesterol, LDL cholesterol, and serum triglyceride levels in diet-induced hypercholesterolemic hamsters. Findings suggest the potential of the oral microencapsulated probiotic cell formulation as a functional nutritional alternative for managing excessive serum cholesterol and triglyceride levels.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Uptake and intracellular fate of surface-modified gold nanoparticles

Abstract: Understanding and controlling the interactions between nanoscale objects and living cells is of great importance for arising diagnostic and therapeutic applications of nanoparticles and for nanotoxicology studies. Here we report a detailed transmission electron microscopy (TEM) study of the uptake of ca. 16 nm surface-modified gold nanoparticles by human fibroblast cells (HeLa cells). It is demonstrated that the well-established endosomal route of cellular uptake can be bypassed to a significant extent by controlling the uptake mechanism either via the delivery of the nanoparticles by liposomes or by surface modification of the nanoparticles with so-called cell penetrating peptides (CPPs). Successful nuclear targeting is demonstrated using surface modification with a cocktail of CPPs and a peptide acting as a nuclear localization signal (NLS).