Andrejs Ivanovs

Learn More
The aorta-gonad-mesonephros region plays an important role in hematopoietic stem cell (HSC) development during mouse embryogenesis. The vascular endothelial cadherin⁺ CD45⁺ (VE-cad⁺CD45⁺) population contains the major type of immature pre-HSCs capable of developing into long-term repopulating definitive HSCs. In this study, we developed a new coaggregation(More)
Primary ciliary dyskinesia (PCD) is an autosomal recessive disease with extensive genetic heterogeneity. Dyskinetic or completely absent motility of cilia predisposes to recurrent pulmonary and upper respiratory tract infections resulting in bronchiectasis. Also infections of the middle ear are common due to lack of ciliary movement in the Eustachian tube.(More)
Hematopoietic stem cells (HSCs) emerge during embryogenesis and maintain hematopoiesis in the adult organism. Little is known about the embryonic development of human HSCs. We demonstrate that human HSCs emerge first in the aorta-gonad-mesonephros (AGM) region, specifically in the dorsal aorta, and only later appear in the yolk sac, liver, and placenta. AGM(More)
One day prior to mass emergence of haematopoietic stem cells (HSCs) in the foetal liver at E12.5, the embryo contains only a few definitive HSCs. It is thought that the burst of HSC activity in the foetal liver is underpinned by rapid maturation of immature embryonic precursors of definitive HSCs, termed pre-HSCs. However, because pre-HSCs are not(More)
In various vertebrate species, the dorsal aorta (Ao) is the site of specification of adult hematopoietic stem cells (HSCs). It has been observed that the upregulation of essential hematopoietic transcription factors and the formation of specific intra-aortic hematopoietic cell clusters occur predominantly in the ventral domain of the Ao (AoV). In the mouse,(More)
The hematopoietic system undergoes rapid changes during embryogenesis; therefore, studying this process requires accurate embryo staging. In the mouse, timed pregnancies can routinely be set and controlled; however, accurate staging of human pregnancies is more problematic, compounded by different ways that gestational age is assessed. Although(More)
Introduction The number of patients with HIV/TB alliance has increased recently. There were 1055 TB/HIV cases registered in European Union (6% out of 17 650 TB cases tested for HIV) in 2010, among them 71 in Latvia (9.5% out of all TB cases in 2010, in comparison with 0.5% in 2000). The treatment for TB/HIV cases is provided in Latvia according to WHO(More)
Tuberculosis (TB) is commonly linked to poverty, overcrowding and malnutrition. It was known earlier that TB more frequently attacks the most vulnerable part of the society – people who have lower socioeconomic status and harmful habits. Being aware of determinants of TB, attenuation of morbidity can be accomplished. This paper identifies impact of(More)
Tissue investigation remains one of the most reliable diagnostic ways in both general medical practice and liver pathology. At present, the routine liver biopsy investigation should include obtaining a representative tissue sample, adequate technological processing and application of histochemical stain panel [1-5]. The evaluation must be done in accordance(More)