Publications by authors named "Petra Stojkovic"

Plastic pollution is increasing at an alarming rate yet the impact of this pollution on human health is poorly understood. Because human induced pluripotent stem cells (hiPSC) are frequently derived from dermal fibroblasts, these cells offer a powerful platform for the identification of molecular biomarkers of environmental pollution in human cells. Here, we describe a novel proof-of-concept for deriving hiPSC from human dermal fibroblasts deliberately exposed to polystyrene (PS) nanoplastic particles; unexposed hiPSC served as controls.

View Article and Find Full Text PDF

Commercially manufactured or generated through environmental degradation, microplastics (MPs) and nanoplastics (NPs) considerably contribute to environmental pollution. There is a knowledge gap in how exposure to MPs/NPs changes cellular function and affects animal and human health. Here, we demonstrate that after oral uptake, fluorescent polystyrene (PS) nanoparticles pass through the mouse digestive system, accumulate and aggregate in different organs, and induce functional changes in cells and organs.

View Article and Find Full Text PDF

Hearing loss (HL) is a major global health problem of pandemic proportions. The most common type of HL is sensorineural hearing loss (SNHL) which typically occurs when cells within the inner ear are damaged. Human induced pluripotent stem cells (hiPSCs) can be generated from any individual including those who suffer from different types of HL.

View Article and Find Full Text PDF

Increase in plastic pollution causes irreparable harm to the environment lasting for decades. While current data of plastic pollution include marine and terrestrial ecology, the impacts of degraded or intentionally produced microscopic-sized plastics on human health remain unknown. Here, we are proposing the usage of pluripotent stem cells, modern transcriptomics, and bioinformatics as a unique scientific tool to define the link between environmental and intracellular pollution, its outcome on early human development and origin of diseases.

View Article and Find Full Text PDF

Increased pollution by plastics has become a serious global environmental problem, but the concerns for human health have been raised after reported presence of microplastics (MPs) and nanoplastics (NPs) in food and beverages. Unfortunately, few studies have investigate the potentially harmful effects of MPs/NPs on early human development and human health. Therefore, we used a new platform to study possible effects of polystyrene NPs (PSNPs) on the transcription profile of preimplantation human embryos and human induced pluripotent stem cells (hiPSCs).

View Article and Find Full Text PDF

Neural differentiation of human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs) can produce a valuable and robust source of human neural cell subtypes, holding great promise for the study of neurogenesis and development, and for treating neurological diseases. However, current hESCs and hiPSCs neural differentiation protocols require either animal factors or embryoid body formation, which decreases efficiency and yield, and strongly limits medical applications. Here we develop a simple, animal-free protocol for neural conversion of both hESCs and hiPSCs in adherent culture conditions.

View Article and Find Full Text PDF

Stem cells (SCs) represent a new therapeutic approach for spinal cord injury (SCI) by enabling improved sensory and motor functions in animal models. The main goal of SC-based therapy for SCI is the replacement of neurons and glial cells that undergo cell death soon after injury. Stem cells are able to promote remyelination via oligodendroglia cell replacement to produce trophic factors enhancing neurite outgrowth, axonal elongation, and fiber density and to activate resident or transplanted progenitor cells across the lesion cavity.

View Article and Find Full Text PDF

Introduction: Stem cells are cells with the ability to grow and differentiate into more than 200 cell types.

Sources Of Data: We review here the characteristics and potential of human embryonic stem cells (hESCs), induced pluripotent stem cells (iPSCs) and adult stem cells (ASCs).

Areas Of Agreement: The differentiation ability of all stem cell types could be stimulated to obtain specialized cells that represent renewable sources of functional cells useful for cell-based therapy.

View Article and Find Full Text PDF

Background: It has long been appreciated that environmental cues may trigger adaptive responses. Many of these responses are a result of changes in the epigenetic landscape influencing transcriptional states and consequently altering phenotypes. In the context of human reproductive health, the procedures necessary for assisted reproduction may result in altered phenotypes by primarily influencing DNA methylation.

View Article and Find Full Text PDF

The most valuable property of stem cells (SCs) is their potential to differentiate into many or all cell types of the body. So far, monitoring SC differentiation has only been possible after cells were fixed or destroyed during sample preparation. It is, however, important to develop nondestructive methods of monitoring SCs.

View Article and Find Full Text PDF

Background: Human embryonic stem cells (hESC) provide a unique model to study early events in human development. The hESC-derived cells can potentially be used to replace or restore different tissues including neuronal that have been damaged by disease or injury.

Methodology And Principal Findings: The cells of two different hESC lines were converted to neural rosettes using adherent and chemically defined conditions.

View Article and Find Full Text PDF

Human embryonic stem cells (hESC) promise tremendous potential as a developmental and cell therapeutic tool. The combined effort of stimulatory and inhibitory signals regulating gene expression, which drives the tissue differentiation and morphogenetic processes during early embryogenesis, is still very poorly understood. With the scarcity of availability of human embryos for research, hESC can be used as an alternative source to study the early human embryogenesis.

View Article and Find Full Text PDF

Human embryonic stem cells (hESC) hold huge promise in modern regenerative medicine, drug discovery, and as a model for studying early human development. However, usage of embryos and derivation of hESC for research and potential medical application has resulted in polarized ethical debates since the process involves destruction of viable developing human embryos. Here we describe that not only developing embryos (morulae and blastocysts) of both good and poor quality but also arrested embryos could be used for the derivation of hESC.

View Article and Find Full Text PDF

Understanding the molecular mechanism by which pluripotency is maintained in human embryonic stem cells (hESC) is important for the development of improved methods to derive, culture and differentiate these into cells of potential therapeutic use. Large-scale transcriptional comparison of the hES-NCL1 line derived from a day 8 embryo with H1 line derived from a day 5 embryo (WiCell Inc.) showed that only 0.

View Article and Find Full Text PDF

The development and transplantation of autologous cells derived from nuclear transfer embryonic stem cell (NT-ESC) lines to treat patients suffering from disease has been termed therapeutic cloning. Human NT is still a developing field, with further research required to improve somatic cell NT and human embryonic stem cell differentiation to deliver safe and effective cell replacement therapies. Furthermore, the implications of transferring mitochondrial heteroplasmic cells, which may harbor aberrant epigenetic gene expression profiles, are of concern.

View Article and Find Full Text PDF

This paper describes the derivation of a blastocyst following heterologous nuclear transfer (NT) into a human oocyte. It also demonstrates that a major obstacle to continuing research in human NT is the availability of suitable human oocytes. In this study, 36 oocytes were donated by 11 women undergoing four different treatments and their developmental potential was evaluated after NT.

View Article and Find Full Text PDF

The homeobox transcription factor Nanog has been proposed to play a crucial role in the maintenance of the undifferentiated state of murine embryonic stem cells. A human counterpart, NANOG, has been identified, but its function and localization have not hitherto been described. We have used a combination of RNA interference and quantitative real-time polymerase chain reaction to study NANOG in human embryonic stem and embryonic carcinoma cells.

View Article and Find Full Text PDF

One of the most frequently used matrices for feeder-free growth of undifferentiated human embryonic stem cells (hESCs) is Matrigel, which supports attachment and growth of undifferentiated hESCs in the presence of mouse embryonic fibroblast-conditioned medium. Unfortunately, application of Matrigel or medium conditioned by mouse embryonic feeder cells is not ideal for potential medical application of hESCs because xenogeneic pathogens can be transmitted through culture conditions. We demonstrate here that human serum as matrix and medium conditioned by differentiated hESCs reduce exposure of hESCs to animal ingredients and provide a safer direction toward completely animal-free conditions for application, handling, and understanding of hESC biology.

View Article and Find Full Text PDF

Human embryonic stem cells (hESCs) have great potential as a source of cells for therapeutic uses, but their culture requires the support of mouse or human cells, either directly as a feeder cell layer or indirectly as a source of conditioned medium in feeder-free culture systems. Unfortunately, the risks of cross-transfer of pathogens from xenogeneic or allogeneic feeders or cell by-products limit their medical applications. In addition, not all human feeders support the growth of hESCs equally well, and ethical concerns have been raised regarding the derivation of feeder cells from aborted human fetuses.

View Article and Find Full Text PDF

There are several different technical approaches to the isolation of hematopoietic stem cells (HSCs) with long-term repopulating ability, but these have problems in terms of yield, complexity, or cell viability. Simpler strategies for HSC isolation are needed. We have enriched primitive hematopoietic progenitors from murine bone marrow of mice from different genetic backgrounds by lineage depletion followed by selection of cells with high aldehyde dehydrogenase activity using the Aldefluor reagent (BD Biosciences, Oxford, U.

View Article and Find Full Text PDF

Human embryonic stem cells (hESCs) have been derived from the inner cell mass (ICM) of day 5-7 blastocysts and hold great promise for research into human developmental biology and the development of cell therapies for the treatment of human diseases. We report here that our novel three-step culture conditions successfully support the development of day-8 human blastocysts, which possess significantly (p <.01) more ICM cells than day-6 blastocysts.

View Article and Find Full Text PDF

A PHP Error was encountered

Severity: Warning

Message: fopen(/var/lib/php/sessions/ci_sessioncllobltpplb6iti8vkifah7m1kfddsp3): Failed to open stream: No space left on device

Filename: drivers/Session_files_driver.php

Line Number: 177

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once

A PHP Error was encountered

Severity: Warning

Message: session_start(): Failed to read session data: user (path: /var/lib/php/sessions)

Filename: Session/Session.php

Line Number: 137

Backtrace:

File: /var/www/html/index.php
Line: 316
Function: require_once