Tiina Titma

Dr. Tiina Titma

Department of Health Technologies, School of Information Technologies, Tallinn University of Technology, Tallinn 12618, Estonia
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Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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21 July 2014 in PLOS ONE
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Angela IvaskAngela Ivask
Angela Ivask
IKImbi Kurvet
Imbi Kurvet
Kaja KasemetsKaja Kasemets
Kaja Kasemets
IBIrina Blinova
Irina Blinova
VAVillem Aruoja
Villem Aruoja
AKAnne Kahru
Anne Kahru
The concept of nanotechnologies is based on size-dependent properties of particles in the 1–100 nm range. However, the relation between the particle size and biological effects is still unclear. The aim of the current paper was to generate and analyse a homogenous set of experimental toxicity data on Ag nanoparticles (Ag NPs) of similar coating (citrate) but of 5 different primary sizes (10, 20, 40, 60 and 80 nm) to different types of organisms/cells commonly used in toxicity assays: bacterial, yeast and algal cells, crustaceans and mammalian cells in vitro. When possible, the assays were conducted in ultrapure water to minimise the effect of medium components on silver speciation. The toxic effects of NPs to different organisms varied about two orders of magnitude, being the lowest (∼0.1 mg Ag/L) for crustaceans and algae and the highest (∼26 mg Ag/L) for mammalian cells. To quantify the role of Ag ions in the toxicity of Ag NPs, we normalized the EC50 values to Ag ions that dissolved from the NPs. The analysis showed that the toxicity of 20–80 nm Ag NPs could fully be explained by released Ag ions whereas 10 nm Ag NPs proved more toxic than predicted. Using E. coli Ag-biosensor, we demonstrated that 10 nm Ag NPs were more bioavailable to E. coli than silver salt (AgNO3). Thus, one may infer that 10 nm Ag NPs had more efficient cell-particle contact resulting in higher intracellular bioavailability of silver than in case of bigger NPs. Although the latter conclusion is initially based on one test organism, it may lead to an explanation for “size-dependent“ biological effects of silver NPs. This study, for the first time, investigated the size-dependent toxic effects of a well-characterized library of Ag NPs to several microbial species, protozoans, algae, crustaceans and mammalian cells in vitro.

27 January 2020 in Current Vascular Pharmacology
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MVMargus Viigimaa
Margus Viigimaa
ASAlexandros Sachinidis
Alexandros Sachinidis
MTMaria Toumpourleka
Maria Toumpourleka
KKKonstantinos Koutsampasopoulos
Konstantinos Koutsampasopoulos
SASigne Alliksoo
Signe Alliksoo
TTTiina Titma
Tiina Titma
Background: Type 2 diabetes mellitus (T2DM) has emerged as a pandemic. It has different complications, both microvascular and macrovascular. Objective: The purpose of this review is to summarize the different types of macrovascular complications associated with T2DM. Methods: A comprehensive review of the literature was performed to identify clinical studies, which determine the macrovascular complications associated with T2DM. Results: Macrovascular complications of T2DM include coronary heart disease, cardiomyopathy, arrhythmias and sudden death, cerebrovascular disease and peripheral artery disease. Cardiovascular disease is the primary cause of death in diabetic patients. Many clinical studies have shown a connection between T2DM and vascular disease, but almost always other risk factors are present in diabetic patients, such as hypertension, obesity and dyslipidaemia. Conclusion: T2DM causes a variety of macrovascular complications through different pathogenetic pathways that include hyperglycaemia and insulin resistance. The association between T2DM and cardiovascular disease is clear, but we need more clinical studies in order to identify the pure effect of T2DM.

27 July 2021 in Nature Methods
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IWIan Walsh
Ian Walsh
DFDmytro Fishman
Dmytro Fishman
DGDario Garcia-Gasulla
Dario Garcia-Gasulla
TTTiina Titma
Tiina Titma
GPGianluca Pollastri
Gianluca Pollastri
STSilvio Tosatto
Silvio Tosatto

16 June 2015 in Current Topics in Medicinal Chemistry
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Journal Article
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Angela IvaskAngela Ivask
Angela Ivask
TTTiina Titma
Tiina Titma
MVMeeri Visnapuu
Meeri Visnapuu
HVHeiki Vija
Heiki Vija
AKAleksandr Kakinen
Aleksandr Kakinen
AKAnne Kahru
Anne Kahru
The knowledge on potential harmful effects of metallic nanomaterials lags behind their increased use in consumer products and therefore, the safety data on various nanomaterials applicable for risk assessment are urgently needed. In this study, 11 metal oxide nanoparticles (MeOx NPs) prepared using flame pyrolysis method were analyzed for their toxicity against human alveolar epithelial cells A549, human epithelial colorectal cells Caco2 and murine fibroblast cell line Balb/c 3T3. The cell lines were exposed for 24 h to suspensions of 3-100 μg/mL MeOx NPs and cellular viability was evaluated using. Neutral Red Uptake (NRU) assay. In parallel to NPs, toxicity of soluble salts of respective metals was analyzed, to reveal the possible cellular effects of metal ions shedding from the NPs. The potency of MeOx to produce reactive oxygen species was evaluated in the cell-free assay. The used three cell lines showed comparable toxicity responses to NPs and their metal ion counterparts in the current test setting. Six MeOx NPs (Al2O3, Fe3O4, MgO, SiO2, TiO2, WO3) did not show toxic effects below 100 µg/mL. For five MeOx NPs, the averaged 24 h IC50 values for the three mammalian cell lines were 16.4 µg/mL for CuO, 22.4 µg/mL for ZnO, 57.3 µg/mL for Sb2O3, 132.3 µg/mL for Mn3O4 and 129 µg/mL for Co3O4. Comparison of the dissolution level of MeOx and the toxicity of soluble salts allowed to conclude that the toxicity of CuO, ZnO and Sb2O3 NPs was driven by release of metal ions. The toxic effects of Mn3O4 and Co3O4 could be attributed to the ROS-inducing ability of these NPs. All the NPs were internalized by the cells according to light microscopy studies but also proven by TEM, and internalization of Co3O4 NPs seemed to be most prominent in this aspect. In conclusion, this work provides valuable toxicological data for a library of 11 MeOx NPs. Combining the knowledge on toxic or non-toxic nature of nanomaterials may be used for safe-by-design approach.

18 November 2017 in Journal of Community Genetics
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LKL. Kalokairinou
L. Kalokairinou
HHH. C. Howard
H. C. Howard
SSS. Slokenberga
S. Slokenberga
EFE. Fisher
E. Fisher
MFM. Flatscher-Thöni
M. Flatscher-Thöni
PBPascal Borry
Pascal Borry
Despite the increasing availability of direct-to-consumer (DTC) genetic testing, it is currently unclear how such services are regulated in Europe, due to the lack of EU or national legislation specifically addressing this issue. In this article, we provide an overview of laws that could potentially impact the regulation of DTC genetic testing in 26 European countries, namely Austria, Belgium, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, the Netherlands and the United Kingdom. Emphasis is placed on provisions relating to medical supervision, genetic counselling and informed consent. Our results indicate that currently there is a wide spectrum of laws regarding genetic testing in Europe. There are countries (e.g. France and Germany) which essentially ban DTC genetic testing, while in others (e.g. Luxembourg and Poland) DTC genetic testing may only be restricted by general laws, usually regarding health care services and patients’ rights.

1 January 2016 in Carbohydrate Polymers
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OBOlesja Bondarenko
Olesja Bondarenko
Angela IvaskAngela Ivask
Angela Ivask
AKAnne Kahru
Anne Kahru
HVHeiki Vija
Heiki Vija
TTTiina Titma
Tiina Titma
TATiina Alamäe
Tiina Alamäe