Cell therapy of myocardial infarction (MI) is under clinical investigation, yet little is known about its underlying mechanism of function. Our aims were to induce a sub-lethal myocardial infarction in a rabbit, to evaluate the abilities of labeled bone marrow mononuclear cells to migrate from the vessel bed into extracellular space of the myocardium, and to evaluate the short-term distribution of cells in the damaged left ventricle. Sub-lethal myocardial infarction was induced in rabbits by ligation of the left coronary vessel branch (in vivo). The Langendorff heart perfusion model (ex vivo) was used in the next phase. The hearts subjected to MI induction were divided into 3 groups (P1-P3), and hearts without MI formed a control group (C). Nanoparticles-labeled bone marrow mononuclear cells were injected into coronary arteries via the aorta. Perfusion after application lasted 2 minutes in the P1 group, 10 minutes in the P2 and C groups, and 25 minutes in the P3 group. The myocardium of the left ventricle was examined histologically, and the numbers of labeled cells in vessels, myocardium, and combined were determined. The numbers of detected cells in the P1 and C groups were significantly lower than in the P2 and P3 groups. In the P2 and P3 groups, the numbers of cells found distally from the ligation were significantly higher than proximally from the ligation site. Bone marrow mononuclear cells labeled with iron oxide nanoparticles proved the ability to migrate in the myocardium interstitium with significantly higher affinity for the tissue damaged by infarction.

• MeSH
• barvení a značení * MeSH
• buňky kostní dřeně metabolismus   patologie   ultrastruktura   MeSH
• časové faktory MeSH
• infarkt myokardu metabolismus   patologie   MeSH
• kinetika MeSH
• koronární cévy metabolismus   patologie   MeSH
• kovové nanočástice MeSH
• králíci MeSH
• leukocyty mononukleární metabolismus   MeSH
• modely nemocí na zvířatech MeSH
• myokard metabolismus   patologie   MeSH
• nanočástice * MeSH
• neparametrická statistika MeSH
• perfuze MeSH
• srdce MeSH
• techniky in vitro MeSH
• železo metabolismus   MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• železo MeSH

New surface-modified iron oxide nanoparticles were developed by precipitation of Fe(II) and Fe(III) salts with ammonium hydroxide according to two methods. In the first method, precipitation was done in the presence of D-mannose solution (in situ coating); the second method involved oxidation of precipitated magnetite with sodium hypochlorite followed by addition of D-mannose solution (postsynthesis coating). Selected nanoparticles were characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM), elemental analysis, dynamic light scattering, infrared (IR), X-ray powder analysis, and ultrasonic spectrometry. While the first preparation method produced very fine nanoparticles ca. 2 nm in diameter, the second one yielded ca. 6 nm particles. Addition of D-mannose after synthesis did not affect the iron oxide particle size. UV-vis spectroscopy suggested that D-mannose suppresses the nonspecific sorption of serum proteins from DMEM culture medium on magnetic nanoparticles. Rat bone marrow stromal cells (rMSCs) were labeled with uncoated and d-mannose-modified iron oxide nanoparticles and with Endorem (Guerbet, France; control). Optical and transmission electron microscopy confirmed the presence of D-mannose-modified iron oxide nanoparticles inside the cells. D-mannose-modified nanoparticles crossed the cell membranes and were internalized well by the cells. Relaxivity measurements of labeled cells in gelatin revealed very high relaxivities only for postsynthesis D-mannose-coated iron oxide nanoparticles.

• MeSH
• barvení a značení metody   MeSH
• buňky kostní dřeně ultrastruktura   MeSH
• buňky stromatu ultrastruktura   MeSH
• kmenové buňky ultrastruktura   MeSH
• kovové nanočástice chemie   MeSH
• krysa rodu Rattus MeSH
• mannosa chemie   MeSH
• roztoky chemie   MeSH
• spektrální analýza MeSH
• transmisní elektronová mikroskopie MeSH
• velikost částic MeSH
• železité sloučeniny chemie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• ferric oxide MeSH Prohlížeč
• mannosa MeSH
• roztoky MeSH
• železité sloučeniny MeSH

Early erythroid precursors were studied in human bone marrow smears to provide more information on small proerythroblasts--"microproerythroblasts"--using a silver reaction to demonstrate silver stained nucleolar organizer regions (AgNORs) and light microscopic densitometry of large irregularly shaped nucleoli and cytoplasm stained for RNA. No significant differences were found for the density of such nucleoli and basophilic cytoplasm between characteristic large proerythroblasts with a nuclear diameter larger that 9 microm (K2 and K1 erythroblasts) and small proerythroblasts--"microproerythroblasts" representing a subpopulation of K1/2 erythroblasts (early basophilic erythroblasts), which are characterized by a smaller nuclear diameter. In addition, large irregularly shaped nucleoli of "microproerythroblasts" possessed numerous silver stained particles representing AgNORs similar to those of large proerythroblasts. The number of AgNORs in "microproerythroblasts" was slightly, but significantly, smaller than that in large characteristic proerythroblasts.

• MeSH
• artefakty MeSH
• barvení a značení metody   MeSH
• buněčné jadérko chemie   ultrastruktura   MeSH
• buněčné linie MeSH
• buňky kostní dřeně cytologie   patologie   ultrastruktura   MeSH
• chronická myeloidní leukemie patologie   MeSH
• cytoplazma chemie   ultrastruktura   MeSH
• erytroblasty cytologie   patologie   ultrastruktura   MeSH
• histocytochemie MeSH
• konfokální mikroskopie MeSH
• lidé MeSH
• RNA chemie   MeSH
• stříbro chemie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• RNA MeSH
• stříbro MeSH

Nuclear magnetic resonance (MR) imaging provides a noninvasive method for studying the fate of transplanted cells in vivo. We studied, in animals with a cortical photochemical lesion or with a balloon-induced spinal cord compression lesion, the fate of implanted rat bone marrow stromal cells (MSCs) and mouse embryonic stem cells (ESCs) labeled with superparamagnetic iron oxide nanoparticles (Endorem). MSCs were colabeled with bromodeoxyuridine (BrdU), and ESCs were transfected with pEGFP-C1 (eGFP ESCs). Cells were either grafted intracerebrally into the contralateral hemisphere of the adult rat brain or injected intravenously. In vivo MR imaging was used to track their fate; Prussian blue staining and electron microscopy confirmed the presence of iron oxide nanoparticles inside the cells. During the first week postimplantation, grafted cells migrated to the lesion site and populated the border zone of the lesion. Less than 3% of MSCs differentiated into neurons and none into astrocytes; 5% of eGFP ESCs differentiated into neurons, whereas 70% of eGFP ESCs became astrocytes. The implanted cells were visible on MR images as a hypointense area at the injection site, in the corpus callosum and in the lesion. The hypointense signal persisted for more than 50 days. The presence of GFP-positive or BrdU-positive and nanoparticle-labeled cells was confirmed by histological staining. Our study demonstrates that both grafted MSCs and eGFP ESCs labeled with a contrast agent based on iron oxide nanoparticles migrate into the injured CNS. Iron oxide nanoparticles can therefore be used as a marker for the long-term noninvasive MR tracking of implanted stem cells.

• MeSH
• buňky kostní dřeně metabolismus   ultrastruktura   MeSH
• elektronová mikroskopie metody   MeSH
• embryo savčí MeSH
• fosfopyruváthydratasa metabolismus   MeSH
• gliový fibrilární kyselý protein metabolismus   MeSH
• imunohistochemie metody   MeSH
• kmenové buňky metabolismus   ultrastruktura   MeSH
• komprese míchy metabolismus   patologie   terapie   MeSH
• krysa rodu Rattus MeSH
• kultivované buňky MeSH
• luminescentní proteiny metabolismus   MeSH
• magnetická rezonanční tomografie metody   MeSH
• mícha cytologie   metabolismus   transplantace   ultrastruktura   MeSH
• mozek cytologie   metabolismus   ultrastruktura   MeSH
• myši MeSH
• neuroglie metabolismus   patologie   ultrastruktura   MeSH
• neurony metabolismus   patologie   ultrastruktura   MeSH
• poranění mozku metabolismus   patologie   terapie   MeSH
• potkani Wistar MeSH
• transplantace kmenových buněk metody   MeSH
• transplantace kostní dřeně metody   MeSH
• zelené fluorescenční proteiny MeSH
• železité sloučeniny metabolismus   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH
• Názvy látek
• ferric oxide MeSH Prohlížeč
• fosfopyruváthydratasa MeSH
• gliový fibrilární kyselý protein MeSH
• luminescentní proteiny MeSH
• zelené fluorescenční proteiny MeSH
• železité sloučeniny MeSH

Ringed sideroblasts were studied by means of transmission electron microscopy in patients suffering from refractory anaemia with ringed sideroblasts (RARS) of myelodysplastic syndrome (MDS) to provide more information on the structural organization of nucleoli in these abnormal erythroblasts. For control of the electron microscopic observations nucleoli in erythroblasts were also visualized by two widely used cytochemical procedures for the demonstration of RNA and AgNOR proteins. In contrast to previously described ultrastructure of nucleoli in "normal" erythroblasts, nucleoli of ringed erythroblasts in RARS of MDS were frequently characterized by a reduced incidence or lack of dense ribonucleic acid (RNA) containing granular components. Since the dense RNA containing granular components represent preribosomes, such sideroblasts in RARS of MDS exhibit a further nucleolar abnormality, which reflects a severe alteration of the nucleolar ribosome assembly in these abnormal cells. On the other hand, the alteration of the preribosome assembly was not noted in early developmental stages of ringed sideroblasts such as proerythroblasts. In addition, nucleoli in advanced or terminal stages of few ringed sideroblasts also did not exhibit such nucleolar abnormality and thus confirm a great structural and functional variability of these cells. The defect of RNA containing structures in nucleoli of advanced and terminal stages of erythroblasts are in a hormony with the light microscopic cytochemistry, which demonstrated a significantly smaller incidence of micronucleoli in specimens stained for RNA than in those stained for AgNOR (silver stained nucleolus organizer region) proteins.

• MeSH
• buněčné jadérko chemie   ultrastruktura   MeSH
• buňky kostní dřeně ultrastruktura   MeSH
• erytroblasty ultrastruktura   MeSH
• lidé MeSH
• mikroskopie elektronová rastrovací MeSH
• refrakterní anemie krev   MeSH
• RNA ribozomální analýza   ultrastruktura   MeSH
• sideroblastická anemie krev   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• RNA ribozomální MeSH

Higher-order compartments of nuclear chromatin have been defined according to the replication timing, transcriptional activity, and information content (Ferreira et al. 1997, Sadoni et al. 1999). The results presented in this work contribute to this model of nuclear organization. Using different human blood cells, nuclear positioning of genes, centromeres, and whole chromosomes was investigated. Genes are located mostly in the interior of cell nuclei; centromeres are located near the nuclear periphery in agreement with the definition of the higher-order compartments. Genetic loci are found in specific subregions of cell nuclei which form distinct layers at defined centre-of-nucleus to locus distances. Inside these layers, the genetic loci are distributed randomly. Some chromosomes are polarized with genes located in the inner parts of the nucleus and centromere located on the nuclear periphery; polar organization was not found for some other chromosomes. The internal structure of the higher-order compartments as well as the polar and non-polar organization of chromosomes are basically conserved in different cell types and at various stages of the cell cycle. Some features of the nuclear structure are conserved even in differentiated cells and during cellular repair after irradiation, although shifted positioning of genetic loci was systematically observed during these processes.

• MeSH
• buněčné jádro genetika   účinky záření   ultrastruktura   MeSH
• buněčný cyklus MeSH
• buňky kostní dřeně účinky záření   ultrastruktura   MeSH
• centromera účinky záření   MeSH
• geny účinky záření   MeSH
• HL-60 buňky MeSH
• hybridizace in situ fluorescenční MeSH
• interfáze MeSH
• kompartmentace buňky MeSH
• leukopoéza MeSH
• lidé MeSH
• lidské chromozomy účinky záření   MeSH
• lymfocyty cytologie   účinky záření   ultrastruktura   MeSH
• U937 buňky MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The frequency of micronucleated polychromatic erythrocytes (PCEs) in mouse bone marrow was assessed after administration of dipyridamole and/or adenosine monophosphate (AMP) to nonirradiated mice or to mice irradiated 15 min later with a sublethal dose of 6.5 Gy gamma rays. In nonirradiated mice, the administration of the drugs increased the frequency of micronucleated PCEs significantly (by 108%). In contrast, in irradiated mice, the number of radiation-induced micronucleated PCEs was significantly decreased if the mice had been pretreated with dipyridamole or AMP alone (by 24% after administration of each of the compounds) and in particular after administration of the drugs in combination (by 36%).

• MeSH
• adenosinmonofosfát farmakologie   MeSH
• buňky kostní dřeně účinky léků   účinky záření   ultrastruktura   MeSH
• chromozomální aberace MeSH
• dipyridamol farmakologie   MeSH
• erytrocyty účinky léků   účinky záření   ultrastruktura   MeSH
• fixní kombinace léků MeSH
• inbrední kmeny myší MeSH
• inhibitory fosfodiesteras farmakologie   MeSH
• mikrojaderné testy MeSH
• myši MeSH
• poškození DNA MeSH
• radioprotektivní látky farmakologie   MeSH
• záření gama MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• adenosinmonofosfát MeSH
• dipyridamol MeSH
• fixní kombinace léků MeSH
• inhibitory fosfodiesteras MeSH
• radioprotektivní látky MeSH

Changes in the karyotype in three spontaneous Sprague-Dawley rat lymphomas (SD7/95, SD8/96, SD9/96) have been studied in the course of in vivo passages. In individual lymphomas karyological findings of primary disease from lymph nodes were compared with changes found in the 1st and 10th passages of the lymphoma and bone marrow samples. Chromosome studies were performed on direct preparations using the G-banding technique. Chromosome counts of all specimens studied were near diploidy, the majority of metaphase cells being pseudodiploid. In later passages of two lymphomas, the tendency in selection to hyperdiploid karyotype, particularly in bone marrow was observed. The examination revealed an increased percentage of breaks in lymph node cells of primary disease and the existence of nonrandom change, derivative chromosome 11, which occurred in structural variability in all three lymphomas studied. The aberration involving chromosome 11 was evaluated as the addition of unknown material at chromosome band 11q11 or as a duplication or triplication of segment 11q12-q23. If this structural aberration was not found, the excessive derivative chromosome 11 or translocation t(11;13) was proved to be present. Further, rearrangements of chromosomes 13 and 7 were nonrandom chromosome abnormalities revealed in later passages of the lymphomas. The results are in accordance with our previous observations in 14 cases of SD lymphomas that showed nonrandom occurrence of rearrangements concerning chromosome 11 and also relatively frequent translocation involving chromosome 13.

• MeSH
• buňky kostní dřeně ultrastruktura   MeSH
• časové faktory MeSH
• chromozomální aberace * MeSH
• cytogenetika MeSH
• karyotypizace MeSH
• krysa rodu Rattus MeSH
• lymfom genetika   MeSH
• potkani Sprague-Dawley MeSH
• pruhování chromozomů MeSH
• transplantace izogenní MeSH
• transplantace nádorů MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH