Isaia Sotiriadou - Academia.edu (original) (raw)

Papers by Isaia Sotiriadou

Current Medicinal Chemistry, Oct 17, 2016

New drug discovery (NDD) is a fascinating discipline encompassing different facets of medicine, p... more New drug discovery (NDD) is a fascinating discipline encompassing different facets of medicine, pharmacology, biotechnology and chemistry. NDD is very often restricted by efficacy or safety problems of the new clinical candidate in human patients. Drug regulatory authorities have provided various guidelines for advancement of safe new chemical entities (NCEs) in clinical trials which must be strictly followed. In spite of this, various drugs have failed in clinical trials or withdrawn from market because of human safety issues related to cardiotoxicity, hepatotoxicity, neurotoxicity and teratogenicity. The failure of safety prediction was pointed to species specificity issues, lack of mechanistic toxicity data and inadequate clinical trials. These drugs not only affect human health but also cause loss of resources and time. The species specificity issues are partially addressed by use of primary human cells but their availability is very limited. Human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) offer sources for generation of an unlimited number of human somatic cells. The emergence of mechanistic models for toxicity testing with transcriptomics, proteomics along with toxicokinetics readouts based on hESCs and hiPSCs is paving the way to design new human relevant testing strategies. Introduction of these models at the timeframe of lead selection and optimization in parallel with in vitro pharmacokinetic studies will significantly reduce compound attrition rate by selection of safer lead molecules. We focused on upcoming hESCs and hiPSCs based toxicity testing models and their future role to address safety gaps of present drug discovery and development.

Journal of Bacteriology & Parasitology, Aug 18, 2016

Epidemiology and Infection, Sep 25, 2012

Samples from different water sources (n=396) were collected during 2009 and 2011. Wastewater (2-5... more Samples from different water sources (n=396) were collected during 2009 and 2011. Wastewater (2-5 l) was purified by aluminium sulphate flocculation. Surface, ground and drinking waters (400-6400 l) were collected by filtration. Cryptosporidium oocysts and Giardia cysts were further concentrated by sucrose centrifugation. (Oo)cysts were identified by IFT (immunofluorescence test), DAPI (4k,6-diamidino-2-phenylindole) staining and DICM (difference interference contrast microscopy). Out of 206 wastewater samples, 134 (65. 0%) were found to be positive for Giardia cysts and 64 (31. 1%) for Cryptosporidium oocysts. Parasite numbers ranged from 0 to 2436 cysts/l and 0 to 1745 oocysts/l. Eight (4. 2 %) surface and drinking water samples (n=190) were found to be positive for Giardia cysts (0-56000/100 l), and 18 (9. 5%) for Cryptosporidium oocysts (2400/100 l). The purpose of this study was to establish the prevalence and concentrations of Giardia lamblia and Cryptosporidium spp. by detecting (oo)cysts from water samples. This study provides substantial evidence that G. lamblia cysts and Cryptosporidium spp. oocysts are able to enter and circulate in the aquatic environment with negative implications for public health.

Water Science & Technology: Water Supply, Apr 1, 2004

The infectivity of Giardia isolates in Mongolian gerbils and in SCID mice inoculated with a newly... more The infectivity of Giardia isolates in Mongolian gerbils and in SCID mice inoculated with a newly established G. intestinalis strains of human origin (ISO/90/1, ISO/90/2) and a reference strain ATCC 30888 has been investigated. Inoculation of Mongolian gerbils with trophozoites resulted in an acute and reproducible pattern of infection. 36% of inoculated gerbils showed symptoms of infection after a first inoculation, whereas the second inoculation resulted in infection of 85% of the same gerbils. The group of SCID mice infected with ISO/90/2 failed to release cysts in the fecal material, while the second inoculated group infected with ISO/90/1 showed a low number of cysts at 13 days post inoculation. Cyst excretion was intermittent, mostly released during the second and the third week of infection. Mongolian gerbils are a useful animal model, whereas SCID mice are not, to assess viability and infectivity of parasites from various sources. Strain differences may contribute to the development of different pattern of infections, which lead to clinical consequences in the diagnosis of giardiasis.

Environmental Research, 2006

The aim of the present study was to investigate water supplies in southern Russia and Bulgaria, i... more The aim of the present study was to investigate water supplies in southern Russia and Bulgaria, in order to estimate the occurrence of Giardia and Cryptosporidium in drinking water resources from these countries. A total of 166 water samples of different origin (surface, tap, bottled, well, spring and waste water) were collected from Rostov (southern Russia), Sofia and Varna (Bulgaria) Greater Areas and screened for the detection of Giardia cysts and Cryptosporidium oocysts. The method incorporated concentration of water samples by filtration and flocculation, sucrose purification, (oo)cyst detection/identification by immunofluorescence test and differential interference contrast. Sixteen out of 166 samples (9.6%) were positive for Giardia and 30 (18.1%) positive for Cryptosporidium. Both Giardia and Cryptosporidium were detected in tap, river, well and waste waters. Giardia cysts were additionally detected in bottled water. Particularly some river, waste and well water samples were highly contaminated with (oo)cysts. This study has shown that drinking water supplies in Russia and Bulgaria are subject to contamination with Giardia and Cryptosporidium, with potential hazards for the public health.

Acta Tropica, 2013

Human toxoplasmosis is potentially contracted due to consumption of contaminated drinking water a... more Human toxoplasmosis is potentially contracted due to consumption of contaminated drinking water and represents an increasing public health risk worldwide. Toxoplasma gondii oocysts can be resistant to standard disinfection processes, including UV radiation. Increased awareness of the risk of waterborne toxoplasmosis outbreaks has led to an increase in research interest in the detection of oocysts in environmental water systems. Ninety-five environmental water samples from the Lower Rhine area in Germany have been included in the study and examined for the presence of Toxoplasma. Water samples were filtered or flocculated by aluminum sulfate and purified by sucrose density gradient. DNA was then extracted, and the DNA samples were then examined by LAMP analysis. T. gondii DNA was detected in eight out of 83 (9.6%) influent and effluent samples obtained from wastewater treatment plants. All samples (n = 12) from the surface, ground, raw and tap waters tested negative. The purpose of this work was to investigate the occurrence and distribution of Toxoplasma oocysts on the Lower Rhine in Germany. Our study provides evidence that the assay is a sensitive, specific, rapid and cost effective method for the detection of T. gondii and is useful for both the investigations of cases of waterborne outbreaks and for identifying the source of contamination.

Epidemiology and Infection, 2013

SUMMARYWe developed, in bench-scale experiments, a unified loop-mediated isothermal amplification... more SUMMARYWe developed, in bench-scale experiments, a unified loop-mediated isothermal amplification (LAMP) assay for the detection of cutaneous, mucocutaneous and visceral leishmaniasis using DNA of cultivated promastigotes. Two primer sets for the LAMP assay were designed based on the 18S rRNA gene, and their sensitivity and specificity were tested and compared. Both of them were specific for Leishmania as the DNA of all ten Leishmania species tested was amplified, whereas the DNA of other parasites, including that of Trypanosoma, was not. The detection limit for primer set 1 ranged between 30 pg and 3·6 fg, depending on which Leishmania species tested. Primer set 2 showed high sensitivity, but was less sensitive than primer set 1. Our findings lead to the conclusion that the LAMP assay with primer set 1 is a promising and effective assay for the successful detection of a wide range of Leishmania infections using only a unified multiplex LAMP test.

Journal of Bacteriology & Parasitology, Aug 18, 2016

<b>Copyright information:</b>Taken from "Global transcriptome analysis of murine... more <b>Copyright information:</b>Taken from "Global transcriptome analysis of murine embryonic stem cell-derived cardiomyocytes"Genome Biology 2007;8(4):R56-R56.Published online 11 Apr 2007PMCID:PMC1896009. Shown are selected Gene Ontology (GO) annotations (biologic process [BP]) of genes that are differentially expressed in α-MHCcells as compared with the 15-day-old embryoid bodies (EBs) and compared with the α-MHC embryonic stem (ES) cells. A total of 1,845 probe set IDs, which were differentially expressed in α-MHCcells, were converted to Genbank accessions and redundancies were removed. SOURCE was used to obtain GO BP annotations. Genesis was used to visualize and identify GO BP categories of interest and extract corresponding lists of transcripts. The pie chart shows the distribution of these annotations. The bar chart shows the number of genes in the categories adhesion, cell cycle, cell death, cell-cell signalling, cellular metabolism, development, stress response, signal transduction, transcription, and transport separately for upregulated and downregulated transcripts.

Motivation: The field of toxicogenomics (the application of ‘-omics ’ technologies to risk assess... more Motivation: The field of toxicogenomics (the application of ‘-omics ’ technologies to risk assess-ment of compound toxicities) has expanded in the last decade, partly driven by new legislation, aimed at reducing animal testing in chemical risk assessment but mainly as a result of a paradigm change in toxicology towards the use and integration of genome wide data. Many research groups worldwide have generated large amounts of such toxicogenomics data. However, there is no cen-tralized repository for archiving and making these data and associated tools for their analysis easily available. Results: The Data Infrastructure for Chemical Safety Assessment (diXa) is a robust and sustainable infrastructure storing toxicogenomics data. A central data warehouse is connected to a portal with

Human embryonic stem cell-derived test systems for developmental neurotoxicity: a transcriptomics... more Human embryonic stem cell-derived test systems for developmental neurotoxicity: a transcriptomics approach

Global transcriptome analysis of murine embryonic stem cell-derived cardiomyocytes

Developmental neurotoxicity (DNT) and many forms of reproductive toxicity (RT) often manifest the... more Developmental neurotoxicity (DNT) and many forms of reproductive toxicity (RT) often manifest themselves in functional deficits that are not necessarily based on cell death, but rather on minor changes relating to cell differentiation or communication. The fields of DNT/RT would greatly benefit from in vitro tests that allow the identification of toxicant-induced changes of the cellular proteostasis, or of its underlying transcriptome network. Therefore, the 'human embryonic stem cell (hESC)derived novel alternative test systems (ESNATS)' European commission research project established RT tests based on defined differentiation protocols of hESC and their progeny. Valproic acid (VPA) and methylmercury (MeHg) were used as positive control compounds to

Transcriptomic and phenotypic analysis of murine embryonic stem cell derived BMP2 + lineage cells... more Transcriptomic and phenotypic analysis of murine embryonic stem cell derived BMP2 + lineage cells: an insight into mesodermal patterning

<b>Copyright information:</b>Taken from "Global transcriptome analysis of murine... more <b>Copyright information:</b>Taken from "Global transcriptome analysis of murine embryonic stem cell-derived cardiomyocytes"Genome Biology 2007;8(4):R56-R56.Published online 11 Apr 2007PMCID:PMC1896009. Characteristic cardiac action potential (APs) of puromycin purified α-myosin heavy chain (MHC)cells. Most APs had a typical cardiac AP morphology but could not be further specified. Only few APs exhibited typical features of pacemaker-like, atrial-like, or ventricular-like APs. The minimal diastolic potential was -60.2 ± 1.1 mV. The maximal upstroke velocity was 22.9 ± 2.2 V/s. APD, APDand APD(AP duration from maximum to 90%, 50% and 20% repolarization) were 96.4 ± 4.2 ms, 71.1 ± 3.9 ms, and 41.3 ± 2.6 ms, respectively. Representative recordings showing the effect of carbachol (1 μmol/l) and isoproterenol (1 μmol/l) on the spontaneous AP frequency. Statistical analysis of the effects of carbachol (1 μmol/l) and isoproterenol (1 μmol/l) on the spontaneous AP frequency. Carbachol caused a decrease whereas isoproterenol increased the spontaneous AP frequency.

Current Topics in Giardiasis, Dec 13, 2017

This chapter provides a reliable and quick method for detection of Giardia duodenalis (which caus... more This chapter provides a reliable and quick method for detection of Giardia duodenalis (which causes a dangerous diarrheal disease), prevention of further spreading, identification of the source of contamination, and eventually minimize health risk and economic damage normally caused by an outbreak. The loop-mediated isothermal amplification (LAMP) method is based on the enrichment of parasite-specific nucleotide sequences, similar to PCR, but it is significantly faster and less susceptible to interference. Here, we give an overview of how we developed this method, and using the example of G. duodenalis as a water-associated pathogen, we present an optimized examination scheme for its detection in water. For this purpose, we have analyzed data from extensive electronic libraries PubMed®/MEDLINE®, filtered out relevant articles with a keyword search, and summarized them. The number of publications on LAMP method has generally increased steadily since its first report in 2000. LAMP, used for detection of Giardia, especially surpasses all other methods due to the high specificity, sensitivity, robustness, and cost effectiveness. The ever-increasing number of publications on application of LAMP is similar to the development of PCR in the 1990s of the last century. Certainly, the method will be further developed in future, but it already offers many advantages over other methods for effective detection of G. duodenalis infections and will therefore certainly gain in popularity.

Diagnostic Microbiology and Infectious Disease, 2008

The development and evaluation of a 1-step single-tube accelerated loop-mediated isothermal ampli... more The development and evaluation of a 1-step single-tube accelerated loop-mediated isothermal amplification (LAMP) assay for the rapid detection of Toxoplasma in water samples is described. The method has been evaluated based on the amplification of B1 and TgOWP Toxoplasma genes, and it demonstrated a sensitivity detection limit of 0.1 tachyzoites' DNA for both genes. LAMP detection was evaluated and compared

Circulation, 2012

Background— The sinoatrial node is the main impulse-generating tissue in the heart. Atrioventricu... more Background— The sinoatrial node is the main impulse-generating tissue in the heart. Atrioventricular conduction block and arrhythmias caused by sinoatrial node dysfunction are clinically important and generally treated with electronic pacemakers. Although an excellent solution, electronic pacemakers incorporate limitations that have stimulated research on biological pacing. To assess the suitability of potential biological pacemakers, we tested the hypothesis that the spontaneous electric activity of human embryonic stem cell–derived cardiomyocytes (hESC-CMs) and induced pluripotent stem cell–derived cardiomyocytes (iPSC-CMs) exhibit beat rate variability and power-law behavior comparable to those of human sinoatrial node. Methods and Results— We recorded extracellular electrograms from hESC-CMs and iPSC-CMs under stable conditions for up to 15 days. The beat rate time series of the spontaneous activity were examined in terms of their power spectral density and additional methods de...

The American Journal of Tropical Medicine and Hygiene, 2013

We previously described loop-mediated isothermal amplification (LAMP) for detection of Schistosom... more We previously described loop-mediated isothermal amplification (LAMP) for detection of Schistosoma haematobium and S. mansoni DNA in infected snails. In the present study, we adapted the LAMP assay for application in field laboratories in schistosomiasis-endemic areas. Isolation of DNA was simplified by blotting snail tissue (extracted in NaOH/sodium dodecyl sulfate) onto treated membranes, which enabled preservation at ambient temperatures. A ready-mix of LAMP reagents, suitable for shipment at ambient temperature and storage in minimal refrigeration, was used. Local survey teams without experience in molecular biology acquired operational expertise with this test within a few hours. Fifty-four field-caught snails were tested locally by LAMP and 59 were tested at similar conditions in Jerusalem. The LAMP results were consistent with those of a polymerase chain reaction; only four samples showed false-negative results. Results indicate that LAMP assays are suitable for detection of S. haematobium and S. mansoni in low-technology parasitology laboratories in which schistosomiasis elimination activities are undertaken.

Current Medicinal Chemistry, Oct 17, 2016

New drug discovery (NDD) is a fascinating discipline encompassing different facets of medicine, p... more New drug discovery (NDD) is a fascinating discipline encompassing different facets of medicine, pharmacology, biotechnology and chemistry. NDD is very often restricted by efficacy or safety problems of the new clinical candidate in human patients. Drug regulatory authorities have provided various guidelines for advancement of safe new chemical entities (NCEs) in clinical trials which must be strictly followed. In spite of this, various drugs have failed in clinical trials or withdrawn from market because of human safety issues related to cardiotoxicity, hepatotoxicity, neurotoxicity and teratogenicity. The failure of safety prediction was pointed to species specificity issues, lack of mechanistic toxicity data and inadequate clinical trials. These drugs not only affect human health but also cause loss of resources and time. The species specificity issues are partially addressed by use of primary human cells but their availability is very limited. Human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) offer sources for generation of an unlimited number of human somatic cells. The emergence of mechanistic models for toxicity testing with transcriptomics, proteomics along with toxicokinetics readouts based on hESCs and hiPSCs is paving the way to design new human relevant testing strategies. Introduction of these models at the timeframe of lead selection and optimization in parallel with in vitro pharmacokinetic studies will significantly reduce compound attrition rate by selection of safer lead molecules. We focused on upcoming hESCs and hiPSCs based toxicity testing models and their future role to address safety gaps of present drug discovery and development.

Journal of Bacteriology & Parasitology, Aug 18, 2016

Epidemiology and Infection, Sep 25, 2012

Samples from different water sources (n=396) were collected during 2009 and 2011. Wastewater (2-5... more Samples from different water sources (n=396) were collected during 2009 and 2011. Wastewater (2-5 l) was purified by aluminium sulphate flocculation. Surface, ground and drinking waters (400-6400 l) were collected by filtration. Cryptosporidium oocysts and Giardia cysts were further concentrated by sucrose centrifugation. (Oo)cysts were identified by IFT (immunofluorescence test), DAPI (4k,6-diamidino-2-phenylindole) staining and DICM (difference interference contrast microscopy). Out of 206 wastewater samples, 134 (65. 0%) were found to be positive for Giardia cysts and 64 (31. 1%) for Cryptosporidium oocysts. Parasite numbers ranged from 0 to 2436 cysts/l and 0 to 1745 oocysts/l. Eight (4. 2 %) surface and drinking water samples (n=190) were found to be positive for Giardia cysts (0-56000/100 l), and 18 (9. 5%) for Cryptosporidium oocysts (2400/100 l). The purpose of this study was to establish the prevalence and concentrations of Giardia lamblia and Cryptosporidium spp. by detecting (oo)cysts from water samples. This study provides substantial evidence that G. lamblia cysts and Cryptosporidium spp. oocysts are able to enter and circulate in the aquatic environment with negative implications for public health.

Water Science & Technology: Water Supply, Apr 1, 2004

The infectivity of Giardia isolates in Mongolian gerbils and in SCID mice inoculated with a newly... more The infectivity of Giardia isolates in Mongolian gerbils and in SCID mice inoculated with a newly established G. intestinalis strains of human origin (ISO/90/1, ISO/90/2) and a reference strain ATCC 30888 has been investigated. Inoculation of Mongolian gerbils with trophozoites resulted in an acute and reproducible pattern of infection. 36% of inoculated gerbils showed symptoms of infection after a first inoculation, whereas the second inoculation resulted in infection of 85% of the same gerbils. The group of SCID mice infected with ISO/90/2 failed to release cysts in the fecal material, while the second inoculated group infected with ISO/90/1 showed a low number of cysts at 13 days post inoculation. Cyst excretion was intermittent, mostly released during the second and the third week of infection. Mongolian gerbils are a useful animal model, whereas SCID mice are not, to assess viability and infectivity of parasites from various sources. Strain differences may contribute to the development of different pattern of infections, which lead to clinical consequences in the diagnosis of giardiasis.

Environmental Research, 2006

The aim of the present study was to investigate water supplies in southern Russia and Bulgaria, i... more The aim of the present study was to investigate water supplies in southern Russia and Bulgaria, in order to estimate the occurrence of Giardia and Cryptosporidium in drinking water resources from these countries. A total of 166 water samples of different origin (surface, tap, bottled, well, spring and waste water) were collected from Rostov (southern Russia), Sofia and Varna (Bulgaria) Greater Areas and screened for the detection of Giardia cysts and Cryptosporidium oocysts. The method incorporated concentration of water samples by filtration and flocculation, sucrose purification, (oo)cyst detection/identification by immunofluorescence test and differential interference contrast. Sixteen out of 166 samples (9.6%) were positive for Giardia and 30 (18.1%) positive for Cryptosporidium. Both Giardia and Cryptosporidium were detected in tap, river, well and waste waters. Giardia cysts were additionally detected in bottled water. Particularly some river, waste and well water samples were highly contaminated with (oo)cysts. This study has shown that drinking water supplies in Russia and Bulgaria are subject to contamination with Giardia and Cryptosporidium, with potential hazards for the public health.

Acta Tropica, 2013

Human toxoplasmosis is potentially contracted due to consumption of contaminated drinking water a... more Human toxoplasmosis is potentially contracted due to consumption of contaminated drinking water and represents an increasing public health risk worldwide. Toxoplasma gondii oocysts can be resistant to standard disinfection processes, including UV radiation. Increased awareness of the risk of waterborne toxoplasmosis outbreaks has led to an increase in research interest in the detection of oocysts in environmental water systems. Ninety-five environmental water samples from the Lower Rhine area in Germany have been included in the study and examined for the presence of Toxoplasma. Water samples were filtered or flocculated by aluminum sulfate and purified by sucrose density gradient. DNA was then extracted, and the DNA samples were then examined by LAMP analysis. T. gondii DNA was detected in eight out of 83 (9.6%) influent and effluent samples obtained from wastewater treatment plants. All samples (n = 12) from the surface, ground, raw and tap waters tested negative. The purpose of this work was to investigate the occurrence and distribution of Toxoplasma oocysts on the Lower Rhine in Germany. Our study provides evidence that the assay is a sensitive, specific, rapid and cost effective method for the detection of T. gondii and is useful for both the investigations of cases of waterborne outbreaks and for identifying the source of contamination.

Epidemiology and Infection, 2013

SUMMARYWe developed, in bench-scale experiments, a unified loop-mediated isothermal amplification... more SUMMARYWe developed, in bench-scale experiments, a unified loop-mediated isothermal amplification (LAMP) assay for the detection of cutaneous, mucocutaneous and visceral leishmaniasis using DNA of cultivated promastigotes. Two primer sets for the LAMP assay were designed based on the 18S rRNA gene, and their sensitivity and specificity were tested and compared. Both of them were specific for Leishmania as the DNA of all ten Leishmania species tested was amplified, whereas the DNA of other parasites, including that of Trypanosoma, was not. The detection limit for primer set 1 ranged between 30 pg and 3·6 fg, depending on which Leishmania species tested. Primer set 2 showed high sensitivity, but was less sensitive than primer set 1. Our findings lead to the conclusion that the LAMP assay with primer set 1 is a promising and effective assay for the successful detection of a wide range of Leishmania infections using only a unified multiplex LAMP test.

Journal of Bacteriology & Parasitology, Aug 18, 2016

<b>Copyright information:</b>Taken from "Global transcriptome analysis of murine... more <b>Copyright information:</b>Taken from "Global transcriptome analysis of murine embryonic stem cell-derived cardiomyocytes"Genome Biology 2007;8(4):R56-R56.Published online 11 Apr 2007PMCID:PMC1896009. Shown are selected Gene Ontology (GO) annotations (biologic process [BP]) of genes that are differentially expressed in α-MHCcells as compared with the 15-day-old embryoid bodies (EBs) and compared with the α-MHC embryonic stem (ES) cells. A total of 1,845 probe set IDs, which were differentially expressed in α-MHCcells, were converted to Genbank accessions and redundancies were removed. SOURCE was used to obtain GO BP annotations. Genesis was used to visualize and identify GO BP categories of interest and extract corresponding lists of transcripts. The pie chart shows the distribution of these annotations. The bar chart shows the number of genes in the categories adhesion, cell cycle, cell death, cell-cell signalling, cellular metabolism, development, stress response, signal transduction, transcription, and transport separately for upregulated and downregulated transcripts.

Motivation: The field of toxicogenomics (the application of ‘-omics ’ technologies to risk assess... more Motivation: The field of toxicogenomics (the application of ‘-omics ’ technologies to risk assess-ment of compound toxicities) has expanded in the last decade, partly driven by new legislation, aimed at reducing animal testing in chemical risk assessment but mainly as a result of a paradigm change in toxicology towards the use and integration of genome wide data. Many research groups worldwide have generated large amounts of such toxicogenomics data. However, there is no cen-tralized repository for archiving and making these data and associated tools for their analysis easily available. Results: The Data Infrastructure for Chemical Safety Assessment (diXa) is a robust and sustainable infrastructure storing toxicogenomics data. A central data warehouse is connected to a portal with

Human embryonic stem cell-derived test systems for developmental neurotoxicity: a transcriptomics... more Human embryonic stem cell-derived test systems for developmental neurotoxicity: a transcriptomics approach

Global transcriptome analysis of murine embryonic stem cell-derived cardiomyocytes

Developmental neurotoxicity (DNT) and many forms of reproductive toxicity (RT) often manifest the... more Developmental neurotoxicity (DNT) and many forms of reproductive toxicity (RT) often manifest themselves in functional deficits that are not necessarily based on cell death, but rather on minor changes relating to cell differentiation or communication. The fields of DNT/RT would greatly benefit from in vitro tests that allow the identification of toxicant-induced changes of the cellular proteostasis, or of its underlying transcriptome network. Therefore, the 'human embryonic stem cell (hESC)derived novel alternative test systems (ESNATS)' European commission research project established RT tests based on defined differentiation protocols of hESC and their progeny. Valproic acid (VPA) and methylmercury (MeHg) were used as positive control compounds to

Transcriptomic and phenotypic analysis of murine embryonic stem cell derived BMP2 + lineage cells... more Transcriptomic and phenotypic analysis of murine embryonic stem cell derived BMP2 + lineage cells: an insight into mesodermal patterning

<b>Copyright information:</b>Taken from "Global transcriptome analysis of murine... more <b>Copyright information:</b>Taken from "Global transcriptome analysis of murine embryonic stem cell-derived cardiomyocytes"Genome Biology 2007;8(4):R56-R56.Published online 11 Apr 2007PMCID:PMC1896009. Characteristic cardiac action potential (APs) of puromycin purified α-myosin heavy chain (MHC)cells. Most APs had a typical cardiac AP morphology but could not be further specified. Only few APs exhibited typical features of pacemaker-like, atrial-like, or ventricular-like APs. The minimal diastolic potential was -60.2 ± 1.1 mV. The maximal upstroke velocity was 22.9 ± 2.2 V/s. APD, APDand APD(AP duration from maximum to 90%, 50% and 20% repolarization) were 96.4 ± 4.2 ms, 71.1 ± 3.9 ms, and 41.3 ± 2.6 ms, respectively. Representative recordings showing the effect of carbachol (1 μmol/l) and isoproterenol (1 μmol/l) on the spontaneous AP frequency. Statistical analysis of the effects of carbachol (1 μmol/l) and isoproterenol (1 μmol/l) on the spontaneous AP frequency. Carbachol caused a decrease whereas isoproterenol increased the spontaneous AP frequency.

Current Topics in Giardiasis, Dec 13, 2017

This chapter provides a reliable and quick method for detection of Giardia duodenalis (which caus... more This chapter provides a reliable and quick method for detection of Giardia duodenalis (which causes a dangerous diarrheal disease), prevention of further spreading, identification of the source of contamination, and eventually minimize health risk and economic damage normally caused by an outbreak. The loop-mediated isothermal amplification (LAMP) method is based on the enrichment of parasite-specific nucleotide sequences, similar to PCR, but it is significantly faster and less susceptible to interference. Here, we give an overview of how we developed this method, and using the example of G. duodenalis as a water-associated pathogen, we present an optimized examination scheme for its detection in water. For this purpose, we have analyzed data from extensive electronic libraries PubMed®/MEDLINE®, filtered out relevant articles with a keyword search, and summarized them. The number of publications on LAMP method has generally increased steadily since its first report in 2000. LAMP, used for detection of Giardia, especially surpasses all other methods due to the high specificity, sensitivity, robustness, and cost effectiveness. The ever-increasing number of publications on application of LAMP is similar to the development of PCR in the 1990s of the last century. Certainly, the method will be further developed in future, but it already offers many advantages over other methods for effective detection of G. duodenalis infections and will therefore certainly gain in popularity.

Diagnostic Microbiology and Infectious Disease, 2008

The development and evaluation of a 1-step single-tube accelerated loop-mediated isothermal ampli... more The development and evaluation of a 1-step single-tube accelerated loop-mediated isothermal amplification (LAMP) assay for the rapid detection of Toxoplasma in water samples is described. The method has been evaluated based on the amplification of B1 and TgOWP Toxoplasma genes, and it demonstrated a sensitivity detection limit of 0.1 tachyzoites' DNA for both genes. LAMP detection was evaluated and compared

Circulation, 2012

Background— The sinoatrial node is the main impulse-generating tissue in the heart. Atrioventricu... more Background— The sinoatrial node is the main impulse-generating tissue in the heart. Atrioventricular conduction block and arrhythmias caused by sinoatrial node dysfunction are clinically important and generally treated with electronic pacemakers. Although an excellent solution, electronic pacemakers incorporate limitations that have stimulated research on biological pacing. To assess the suitability of potential biological pacemakers, we tested the hypothesis that the spontaneous electric activity of human embryonic stem cell–derived cardiomyocytes (hESC-CMs) and induced pluripotent stem cell–derived cardiomyocytes (iPSC-CMs) exhibit beat rate variability and power-law behavior comparable to those of human sinoatrial node. Methods and Results— We recorded extracellular electrograms from hESC-CMs and iPSC-CMs under stable conditions for up to 15 days. The beat rate time series of the spontaneous activity were examined in terms of their power spectral density and additional methods de...

The American Journal of Tropical Medicine and Hygiene, 2013

We previously described loop-mediated isothermal amplification (LAMP) for detection of Schistosom... more We previously described loop-mediated isothermal amplification (LAMP) for detection of Schistosoma haematobium and S. mansoni DNA in infected snails. In the present study, we adapted the LAMP assay for application in field laboratories in schistosomiasis-endemic areas. Isolation of DNA was simplified by blotting snail tissue (extracted in NaOH/sodium dodecyl sulfate) onto treated membranes, which enabled preservation at ambient temperatures. A ready-mix of LAMP reagents, suitable for shipment at ambient temperature and storage in minimal refrigeration, was used. Local survey teams without experience in molecular biology acquired operational expertise with this test within a few hours. Fifty-four field-caught snails were tested locally by LAMP and 59 were tested at similar conditions in Jerusalem. The LAMP results were consistent with those of a polymerase chain reaction; only four samples showed false-negative results. Results indicate that LAMP assays are suitable for detection of S. haematobium and S. mansoni in low-technology parasitology laboratories in which schistosomiasis elimination activities are undertaken.