Recent years have improved our understanding of the plasticity of cell types behind inducing, building, and maintaining different types of teeth. The latest efforts were aided by progress in single-cell transcriptomics, which helped to define not only cell states with mathematical precision but also transitions between them. This includes new aspects of dental epithelial and mesenchymal stem cell niches and beyond. These recent efforts revealed continuous and fluid trajectories connecting cell states during dental development and exposed the natural plasticity of tooth-building progenitors. Such "developmental" plasticity seems to be employed for organizing stem cell niches in adult continuously growing teeth. Furthermore, transitions between mature cell types elicited by trauma might represent a replay of embryonic continuous cell states. Alternatively, they could constitute transitions that evolved de novo, not known from the developmental paradigm. In this review, we discuss and exemplify how dental cell types exhibit plasticity during dynamic processes such as development, self-renewal, repair, and dental replacement. Hypothetically, minor plasticity of cell phenotypes and greater plasticity of transitions between cell subtypes might provide a better response to lifetime challenges, such as damage or dental loss. This plasticity might be additionally harnessed by the evolutionary process during the elaboration of dental cell subtypes in different animal lineages. In turn, the diversification of cell subtypes building teeth brings a diversity of their shape, structural properties, and functions.
- Klíčová slova
- cell differentiation, dental informatics/bioinformatics, developmental biology, single-cell RNA-seq, stem cell(s), tooth development,
- MeSH
- regenerace fyziologie MeSH
- zuby * MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
Mixed modes of reproduction, combining sexual processes with thelytokous parthenogenesis, occur in all major clades of social insects. In several species of termites, queens maximize their genetic input into nondispersing replacement queens through parthenogenesis, while maintaining genetically diverse sterile offspring and dispersing reproductives via sexual reproduction. This so-called asexual queen succession (AQS) has multiple independent origins and its presumed advantages are diverse as well, ranging from multiplication of colony reproductive potential to extension of its lifespan beyond that of the foundress. However, how AQS shapes colony life cycles under natural conditions remains poorly known. The neotropical termite Silvestritermes minutus inhabits small but conspicuous nests, offering a unique opportunity to investigate the impact of AQS on life history. We report on its breeding system, life cycle and sex allocation using social structure census in 137 nests and genotyping of 12 colonies at 12 microsatellite loci. We show that colonies are established by an outbred pair of primary reproductives. In less than 2 years, the foundress is replaced by multiple neotenic queens, arising mostly through automixis with central fusion. Sterile castes, male and most (93%) female dispersers are produced sexually. Colony reproduction is usually restricted to a single dispersal of alates with unbiased sex ratio, taking place after 3 years. We conclude that S. minutus benefits from AQS to maximize colony growth rate and alate production within a very short life cycle rather than to extend colony lifespan. This highlights the versatile role of AQS in different cases of its polyphyletic origin.
- Klíčová slova
- Silvestritermes minutus, asexual queen succession, breeding system, life history, parthenogenesis, termites,
- MeSH
- genotyp MeSH
- Isoptera genetika fyziologie MeSH
- mikrosatelitní repetice MeSH
- partenogeneze MeSH
- rozmnožování MeSH
- stadia vývoje * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
In organized tissues, the precise geometry and the overall shape are critical for the specialized functions that the cells carry out. Odontoblasts are major matrix-producing cells of the tooth and have also been suggested to participate in sensory transmission. However, refined morphologic data on these important cells are limited, which hampers the analysis and understanding of their cellular functions. We took advantage of fluorescent color-coding genetic tracing to visualize and reconstruct in 3 dimensions single odontoblasts, pulp cells, and their assemblages. Our results show distinct structural features and compartments of odontoblasts at different stages of maturation, with regard to overall cellular shape, formation of the main process, orientation, and matrix deposition. We demonstrate previously unanticipated contacts between the processes of pulp cells and odontoblasts. All reported data are related to mouse incisor tooth. We also show that odontoblasts express TRPM5 and Piezo2 ion channels. Piezo2 is expressed ubiquitously, while TRPM5 is asymmetrically distributed with distinct localization to regions proximal to and within odontoblast processes.
- Klíčová slova
- cell morphology, dentinogenesis, growth/development, protein expression, pulp biology, transgenic animals,
- MeSH
- ameloblasty cytologie ultrastruktura MeSH
- buněčné jádro ultrastruktura MeSH
- buněčné výběžky ultrastruktura MeSH
- dentin ultrastruktura MeSH
- extracelulární matrix ultrastruktura MeSH
- fluorescenční protilátková technika MeSH
- iontové kanály ultrastruktura MeSH
- kationtové kanály TRPM ultrastruktura MeSH
- kompartmentace buňky MeSH
- mezenchymální kmenové buňky cytologie ultrastruktura MeSH
- mikroskopie elektronová rastrovací metody MeSH
- myši transgenní MeSH
- myši MeSH
- odontoblasty cytologie ultrastruktura MeSH
- řezáky cytologie ultrastruktura MeSH
- tvar buňky MeSH
- zobrazování trojrozměrné metody MeSH
- zubní dřeň cytologie ultrastruktura MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- iontové kanály MeSH
- kationtové kanály TRPM MeSH
- Piezo2 protein, mouse MeSH Prohlížeč
- Trpm5 protein, mouse MeSH Prohlížeč
Neural crest cells (NCCs) derive early in vertebrate ontogenesis from neural tube as a population of migratory cells with exquisite differentiation potential. Abnormalities in NCC behaviour are cause of debilitating diseases including cancers and a spectrum of neurocristopathies. Thanks to their multilineage differentiation capacity NCCs offer a cell source for regenerative medicine. Both these aspects make NCC biology an important issue to study, which can currently be addressed using methodologies based on pluripotent stem cells. Here we contributed to understanding the biology of human NCCs by refining the protocol for differentiation/propagation of NCClike cells from human embryonic stem cells and by characterizing the molecular and functional phenotype of such cells. Most importantly, we improved formulation of media for NCC culture, we found that poly-L-ornithine combined with fibronectin provide good support for NCC growth, we unravelled the tendency of cultured NCCs to maintain heterogeneity of CD271 expression, and we showed that NCCs derived here possess the capacity to react to BMP4 signals by dramatically up-regulating MSX1, which is linked to odontogenesis.
- MeSH
- adapalen MeSH
- biologické markery metabolismus MeSH
- buněčná diferenciace * účinky léků MeSH
- crista neuralis cytologie účinky léků metabolismus MeSH
- embryonální kmenové buňky cytologie účinky léků metabolismus MeSH
- fenotyp MeSH
- kostní morfogenetický protein 4 farmakologie MeSH
- lidé MeSH
- naftaleny metabolismus MeSH
- polymerázová řetězová reakce MeSH
- průtoková cytometrie MeSH
- transkripční faktor MSX1 metabolismus MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- adapalen MeSH
- biologické markery MeSH
- kostní morfogenetický protein 4 MeSH
- MSX1 protein, human MeSH Prohlížeč
- naftaleny MeSH
- transkripční faktor MSX1 MeSH
Tooth absence and defects caused by various reasons are frequent events in humans. They are not life threatening but may bring about social consequences. Recent dentistry provides solutions in the form of prosthetics or dental implants; however, several complications and distinct limitations favour bioengineering of dental and periodontal structures. At least two types of cells (epithelial and mesenchymal) have to be recombined to produce a new functional tooth. Moreover, the tooth must be vascularized, innervated and properly anchored in the bone. To study these issues, different approaches have been established in both basic and applied research. In this review, recent strategies and techniques of tooth engineering are comprehensively summarized and discussed, particularly regarding manipulation using stem cells.
- MeSH
- implantace protézy MeSH
- kmenové buňky cytologie MeSH
- lidé MeSH
- tkáňové inženýrství metody trendy MeSH
- tkáňové podpůrné struktury MeSH
- výzkum * MeSH
- zuby fyziologie MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
The complete renal artery embolization is an alternative to surgical nephrectomy in seriously ill patients. Iatrogenic embolization can be used in many different conditions. Refractory nephrotic syndrome represents a very rare indication for embolization. Complete renal artery embolization has usually been complicated by postembolization syndrome (PES) which is characterized by flank pain and fever. Possible immunologic contribution to the PES leads some authors to the administration of corticosteroids to the patients undergoing embolization. We report here a cohort of 13 patients undergoing complete embolization of total 21 kidneys due to refractory nephrotic syndrome non-responding to the various specific treatment regimes. We treated our patients undergoing renal artery embolization according to special protocol containing combination of antibiotic drugs and corticosteroids (CS) to diminish PES and evaluated its influence to the cytokine production. The incidence of PES was less frequent and milder in comparison with the historical group of patients. Significant decrease in plasma levels of tumor necrosis factor α during first post-embolization day (8.37 pre- vs. 5.74 pg/ml post-embolization, P=0.0002) could partially explain the reduction of PES symptoms. The procedure was not complicated by severe complications and represents an elegant alternative to surgical procedure. The accurate timing of the embolization remains a controversial point in this intervention.
- MeSH
- arteria renalis * MeSH
- cytokiny krev MeSH
- dospělí MeSH
- glukokortikoidy terapeutické užití MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- nefrotický syndrom mortalita terapie MeSH
- paliativní péče * MeSH
- terapeutická embolizace škodlivé účinky MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- cytokiny MeSH
- glukokortikoidy MeSH
BACKGROUND: Chronic thromboembolic pulmonary hypertension (CTEPH) in indicated cases can be successfully treated by the endarterectomy of pulmonary arteries (PEA). Symptomatically not treated CTEPH has highly unfavourable prognosis. Five years survival of patients with mean pulmonary pressure over 50 mmHg is only 10%. PEA was not available in the Czech Republic till 2004, when PEA program was initiated it the Cardiocenter of the General teaching hospital in Prague in collaboration with leading clinics in that field (Prof. Mayer, University of Mainz, BRD). METHODS AND RESULTS: Up-to-date surgical technique, which in various modifications has been used at majority of clinics, was elaborated by Jamieson and Daily at University of California in San Diego. It is based on reverse endarterectomy performed during complete circulatory arrest with brain protection by deep hypothermia. Till September 2005 twelve patients were operated with zero mortality. In one patient a suture of atrial septum defect was necessary to perform along. Average time of the circulatory arrest was 45 minutes; duration of the extracorporal circulation was 334 minutes. Average duration of the operation was 450 minutes. Duration of the mechanical ventilation was in average 45.5 hours. After one month already haemodynamic parameters (mPA, CI, PVR) significantly improved or normalized and the average length in the test of six minutes walking increased by 132 meters. CONCLUSION: PEA represents a treatment method for patients with CTEPH and surgically accessible pulmonary artery obstruction. Centralized care of those patients is a rational necessity enabling to get maximum experience with complicated diagnostics and treatment of those patients. Multidisciplinary collaboration is the essential condition for the success of the program.
- MeSH
- arteria pulmonalis chirurgie MeSH
- chronická nemoc MeSH
- dospělí MeSH
- endarterektomie * MeSH
- lidé středního věku MeSH
- lidé MeSH
- míra přežití MeSH
- plicní hypertenze komplikace mortalita chirurgie MeSH
- tromboembolie komplikace chirurgie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
Pyogenic liver abscesses are caused by appendicitis in less than 10%. Also the ascending septic inflammation of portal vein (pylephlebitis) could be a serious complication of intra-abdominal infection. Although pylephlebitis is not frequent today, its' mortality and morbidity rates remain high. We describe a case of young man with fever, abdominal pain, and multiple hepatic abscesses. After the symptomatic relief due to antibiotic therapy the pain returned as a result of the development of portal and mesenteric vein thrombosis. The cause of either hepatic abscesses or thrombosis was not clear at the time of dismissal. 2 months later the patient underwent acute abdominal revision with appendectomy for acute phlegmonous and gangrenous appendicitis. Since that time he has been without any clinical symptoms.
- MeSH
- absces jater komplikace diagnóza MeSH
- akutní bolest břicha etiologie MeSH
- apendicitida komplikace MeSH
- dospělí MeSH
- lidé MeSH
- mezenteriální cévní okluze komplikace MeSH
- vena mesenterica MeSH
- vena portae * MeSH
- žilní trombóza komplikace diagnóza MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
- kazuistiky MeSH
OBJECTIVES: To acquire information about the patient's follow-up evaluation of treating fibroids by uterine artery embolization (UAE). DESIGN: A retrospective multicenter clinical trial. SETTING: Department of Obstetrics and Gynaecology, 1st Faculty of Medicine and the General Faculty Hospital, Charles University, Prague. METHODS: 45 women who underwent the UAE due to uterine fibroids from 1999 to 2003 were asked to complete a questionnaire. The questionnaire included 26 questions asking how the women had been informed and what they had expected. Further questions were focused on the course of embolization itself, early post-procedural difficulties (post-embolization syndrome) and patient's overall evaluation of treatment in a longer term. Those women who had completed the questionnaire and had been ready to co-operate were thereafter examined and included in the follow-up monitoring and, if necessary, further treatment was recommended. RESULTS: Thirty one out of 45 patients from 26 to 48 years of age, who had been addressed (68.9%) answered the questionnaire. UAE was indicated 12 times (38.7%) on account of symptoms, 10 times (32.3%) because of sterility, 5 times (16.1%) as a preventive measure within the framework of family planning and 4 times (12.9%) for an asymptomatic but growing leiomyoma. Twenty seven (87.1%) women were also offered an alternative treatment, which they refused. As far as problems are concerned, 18 (58%) women described the course of treatment as corresponding with what they had expected, 5 times it was less painful, and 8 times it was worse than expected. The long-term results were considered as positive by 87.1% of responders, only 12.9% considered the treatment as failure. 5 in 11 women planning pregnancy became pregnant, 3 of them gave birth in term and 2 miscarried in the 1st trimester. CONCLUSION: From the point of view of the patients, the evaluated method proves highly successful, it is well tolerated and it involves a low risk of complications. It is not possible, at this point, however, to give an unequivocal answer to the question whether the method should also be routinely offered to women who are planning pregnancy.
- MeSH
- arterie MeSH
- dospělí MeSH
- leiomyom krevní zásobení terapie MeSH
- lidé středního věku MeSH
- lidé MeSH
- nádory dělohy krevní zásobení terapie MeSH
- průzkumy a dotazníky MeSH
- spokojenost pacientů MeSH
- terapeutická embolizace * MeSH
- uterus krevní zásobení MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- anglický abstrakt MeSH
- časopisecké články MeSH
Bielavska and colleagues (Bielavska, Sacchetti, Baldi, & Tassoni, 1999) have recently shown that KN-62, an inhibitor of calcium/calmodulin-dependent kinase II (CaCMK), induces conditioned taste aversion (CTA) when introduced into the parabrachial nucleus (PBN) of rats. The aim of the present report was to assess whether activity of CaCMK in the PBN is changed during CTA. We induced CTA in one group of rats by pairing saccharin consumption with an ip injection of lithium chloride. Another group of rats received lithium alone (without being paired with saccharin consumption) to test whether lithium has an effect on CaCMK in the PBN, independent of those effects due to training. In animals receiving CTA training, CaCMK activity in extracts of PBN was reduced by approximately 30% at the postacquisition intervals of 12, 24, and 48 h, compared to control animals receiving saccharin with saline injection. By 120 h after CTA training, no effect on CaCMK was present. At those postacquisition intervals showing CaCMK activity effects due to CTA, there were no effects attributable to lithium alone. Lithium alone produced only a short-lasting reduction in CaCMK activity (at 20 min a 30% decrease, at 60 min a 23% decrease; and at 6, 12, and 24 h no decrease). The time course of lithium-induced effects differed markedly from that of CTA training. All changes were Ca2+/- -dependent; we did not observe any changes in Ca-independent activity. CTA effects on CaCMK were selective for PBN, insofar as we did not observe any CTA effects on CaCMK in the visual cortex, a brain region unrelated to taste pathways. Since CTA produces a relatively long-lasting reduction in CaCMK activity (lasting 2 days or more) specifically in the PBN, which is critical a relay for taste information, the reduction of CaCMK activity may enable the consolidation of taste memory in an aversive situation.
- MeSH
- chuť fyziologie MeSH
- krysa rodu Rattus MeSH
- plexus brachialis metabolismus MeSH
- podmiňování (psychologie) fyziologie MeSH
- potkani Long-Evans MeSH
- proteinkinasy závislé na vápníku a kalmodulinu metabolismus MeSH
- vápník metabolismus MeSH
- zvířata MeSH
- Check Tag
- krysa rodu Rattus MeSH
- mužské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- proteinkinasy závislé na vápníku a kalmodulinu MeSH
- vápník MeSH