Pesticides are substances or mixtures of substances used in agriculture against pests (animals, plants and parasitic fungi), who damage the crops, stocks of agricultural products, food and reduce livestock utility or threaten human health. The thesis consists of two parts. The first (theoretical) part describes composition and function of gut microbiota; pesticides and their classification, environmental transport and effects of these substances on human health, and glyphosate as the active substance of herbicide Roundup, its mechanism of action, environmental fate and proven effects of glyphosate on human. The aim of second (practical) part of this thesis was to test impact of pesticide Roundup on the gut microorganisms of human. The impact of pesticide was tested in in vitro pure cultures. Roundup was added in concentrations of glyphosate 17 g/L, 1,7 g/L and 0,17 g/L to the complex media and after cultivation the growth of microorganisms was evaluated. The next samples of stool were collected from human volunteers; these were cultivated similarly in the complex media with different concentrations of glyphosate. The total numbers of microorganisms, bifidobacteria, lactobacilli, enterococci and coliformn bacteria were defined after cultivation. When the pesticide was tested in pure cultures, concentration of 17 g/L glyphosate significantly inhibited total bacterial growth (P < 0.05), at lower concentrations no difference was observed. The cultivated microorganisms from samples of stool demonstrated only that bifidobacteria are sensitive to glyphosate at the highest used concentration of this pesticide compared with the control sample.

This thesis deals with the influence of zinc various forms on the intestinal microbiota of pigs. At the beginning, the thesis presents a basic overview of nanoparticles, especially zinc one, which have been used in practical terms. Also, the topic of intestinal microbiota in weaned piglets and the effect of nanoparticles on neonatal diarrhea, which is often associated with weaning, is discussed. The practical part deals with the influence of different zinc concentrations on intestinal bacteria at 0, 5, 10 and 20 days after weaning of the pig from the sow. The total number of microorganisms at individual concentrations and also the number of coliform bacteria, which are very often the source of diarrheal diseases, were determined. Four selective agars were used for qualitative assessment of the composition of the intestinal microbiota and the percentage growth on the individual growth medium was determined.

This thesis consists of six research chapters, out of which, five have already been published in research journals, 1 is in the process of submission and the last chapter presents original unpublished confidential data in the process of manuscript preparation. The research presented in this thesis concerns the complex mechanisms of bees and wasps immune system focused on microbiota as component of immunity. As shown in the introduction, highly social and managed species of bees like honey bees and bumble bees, play key roles in natural and agricultural ecosystems worldwide. Recent losses of bees have been attributed to pesticide exposure, poor nutrition, increased parasite loads and habitat degradation. Over the past several years, governments, beekeepers, and the general public worldwide have become concerned by increased losses of honey bee colonies, calling for more research on how to keep colonies healthy. Our main aim was to explore the complex mechanisms of bees and related species gut bacterial populations, their links to insect immunity and investigate the opportunities for an intervention. Part of our aim was to characterise the bumble bee and wasp gut microbiota using 16S RNA sequencing in a search for potentially novel bacterial species. We have tried to explain how microbiome interacts with the host and showed that major members of these communities appear to benefit the host. The simple gut communities of social bees present ideal model systems to investigate the underlying evolutionary and genetic processes of such interactions. Information based on our results may help in the design of proper probiotic supplementation strategies with respect to physiological conditions in the honey bee gut.

Thousands of parrots all over the world suffer from illnesses and medical complications that can result from interactions between their immune system and bacteria in their digestive tract. The aim of this master's thesis is to understand the link between symptoms of these medical issues, the composition of blood and gastrointestinal microbiota in parrots. Using the hematological methods, 198 blood samples representing 53 parrot species were analyzed. The composition of microbiome was defined by combination of a molecular approach using bacterial 16S rRNA gene sequencing in 132 fecal samples, 12 intestine samples, 228 cloacal swabs and 236 beak swabs representing in total 61 parrot species and a diagnostic approach by psittacine fecal Gram's stain method. Significant association of hematological parameters with individual, environmental and clinical factors was observed, as well as its considerable interspecific variability. Absolute heterophile and lymphocyte counts have been shown more useful for infectious and autoimmune disease monitoring than H/L ratio. Relative numbers of basophiles were the best indicator for behavioral disorders. In relation to hematological parameters, the effect of the bacterial family Flavobacteriaceae, as part of the oral microbiota, and the bacteria Escherichia or...

CHARLES UNIVERSITY PHARMACEUTICAL FACULTY IN HRADEC KRÁLOVÉ DEPARTMENT OF PHARMACEUTICAL BOTANY Title of the Diploma thesis: FENOLIC ACIDS IN PLANTS Candidate: Lucie Klížová Supervisor: PharmDr. Jana Karlíčková, Ph.D. Diploma thesis 2020/2021, pp. 153 Phenolic acids belongs between secondary metabolites, which are part of fruits, vegetables, cereals and other plants of different families. For example, it can be plants of family Lamiaceae, Asteraceae and Ericaceae, which contain significant amounts of these substances. In plants phenolic acids play an important role and they have many human health-promoting effects including antioxidant, anti-inflammatory, antiviral, antibacterial, antifungal, anticancer activity and other. Plants containing phenolic acids are preferably also used as antidiabetics, expectorants, insecticides, hypolipidemics, cardioprotective and neurological compounds, etc. The content of these compounds in plants may be different according to monitored cultivar, the place of growth, the time of harvest and many other aspects. Presence, identification and subsequent quantification of individual phenolic acids are usually done through the HPLC and MS methods and total content of these compounds is determined through the Folin-Ciocalteu method. The diploma thesis is a literature...

There is a very few papers to provide an overview of the characteristics of the estrous cycle, the relationship of the estrous cycle to physiological manifestations such as the pH of the vaginal environment, as well as the dynamics of the vaginal microbiota in wild mice. The aim of this thesis is to contribute to the understanding of the dynamic relationship between external influences and the physiology of the female reproductive system, to develop a reliable methodology for measuring the pH of the vaginal microenvironment in mice as well as to quantify the overall abundance of some bacterial taxons by comparing sequencing and qPCR methods. The results suggest that the physical presence of the male in the cage has the most significant effect on the prolongation of the estrus phase, in contrast to non-significant olfactory stimulation of the urine. Fluctuation in the pH of the vaginal environment have also been shown to be cyclic, and the qPCR method shows that the composition of the vaginal microbiota, during the estrus phase, differs significantly from other phases of the estrous cycle, as we confirmed by 16S rRNA sequencing. Thus, these results provide a comprehensive view of the variability of the estrous cycle with an emphasis on the variability of the vaginal microbiota and the change in the...

Hintergrund: Gestillte Kinder haben im Vergleich zu nicht gestillten Kindern eine geringere Inzidenz von gastrointestinalen Infektionen und atopischen Erkrankungen. Man geht davon aus, dass der gesundheitsfördernde Effekt der Muttermilch teilweise über die intestinale Mikrobiota vermittelt wird. Diese ist in Stillkindern durch eine geringe Diversität und einen hohen Anteil an Bifidobakterien charakterisiert. Neueste Ansätze in der Weiterentwicklung industriell hergestellter Säuglingsnahrung zielen darauf ab, eine intestinale Mikrobiota zu fördern, die der von gestillten Kindern ähnelt. Die Supplementation von Säuglingsnahrung mit Probiotika (lebende Mikroorganismen) oder Präbiotika (unverdauliche Kohlenhydrate, die als Energiesubstrat für probiotische Bakterien dienen) könnte die bifidogene und antipathogene, aber auch immunmodulierende Wirkung der Muttermilch nachahmen. Aufgrund unterschiedlicher Interaktionen mit der Darmmikrobiota und dem Immunsystem fokussiert man mit der gleichzeitigen Gabe von Pro- und Präbiotika (Synbiotika) eine synergistische Wirkung an. Zielstellung und Studiendesign: In einer randomisiert-kontrollierten, klinischen Studie wurde untersucht, ob sich in den ersten drei Lebensmonaten von gesunden und termingerecht geborenen Kindern mit einer Synbiotikum-haltigen Säuglingsnahrung eine intestinale Mikrobiota etabliert, die der von gestillten Kindern gleicht. Das Synbiotikum setzte sich aus Bifidobacterium animalis ssp. lactis CNCM I 3446 (ältere Bezeichnung B. lactis BB-12) und Kuhmilcholigosacchariden zusammen. Die Studie umfasste zwei Gruppen von Kindern, die eine Säuglingsnahrung mit (SYN-Gruppe, n=21) oder ohne Supplement (KON-Gruppe, n=18) erhielten. Gestillte Kinder dienten als Referenz (REF-Gruppe, n=23). Um die Diversität der Bifidobakterien auf Speziesebene umfassend zu charakterisieren, wurden quantitative Real-Time PCR (qPCR)-Verfahren, basierend auf dem single-copy groEL als phylogenetisches Zielgen, zur spezifischen Quantifizierung von zwölf Bifidobakterienspezies in humanen Fäzes entwickelt und validiert. Ergebnisse: Die supplementierte Säuglingsnahrung war gut verträglich und unterstützte eine gesunde Entwicklung; vergleichbare anthropometrische Daten von SYN- und REF-Gruppe. Das Synbiotikum stimulierte selektiv das Wachstum von Laktobazillen und Bifidobakterien. Die Zellzahl für Laktobazillen der SYN-Gruppe war zur REF-Gruppe äquivalent (9,07±0,32 versus 9,90±0,27 log10 Zellen/g Fäzes TM [MW±SEM]; p<0,0019; Äquivalenzdifferenz von 1 log10 Zellen/g Fäzes TM) und höher als in der KON-Gruppe (8,27±0,31 log10 Zellen/g Fäzes TM [MW±SEM]). Die Zellzahl für Bifidobakterien war in der SYN-Gruppe am höchsten (11,54±0,05 versus 11,00±0,17 [REF-Gruppe] und 10,54±0,24 [KON-Gruppe] log10 Zellen/g Fäzes TM [MW±SEM]). In der SYN-Gruppe wurde die höchste Anzahl an Bifidobakterienspezies erfasst (167 mit [128 ohne] B. animalis in 56 Fäzesproben versus 98 und 93 in jeweils 51 Fäzesproben der REF- und KON-Gruppe). Neben Kinder-typischen Spezies wie B. bifidum und B. breve wurden auch Spezies, die für Erwachsene charakteristisch sind (B. adolescentis), häufiger in der SYN-Gruppe als in den Vergleichsgruppen nachgewiesen. Der pH-Wert in Fäzes von Kindern aus der SYN-Gruppe war niedriger als der aus der KON-Gruppe (6,07±0,20 versus 6,45±0,17 [MW±SEM]) und näher an dem von gestillten Kindern mit 5,29±0,12 (MW±SEM). Schlussfolgerung: Die Supplementation einer Säuglingsnahrung mit dem Synbiotikum aus CNCM I-3446 und Kuhmilcholigosacchariden führte zu einer Angleichung in der Zusammensetzung der intestinalen Mikrobiota und des fäkalen pH-Wertes an gestillte Kinder. Die in dieser Arbeit entwickelten groEL-basierten qPCR-Verfahren erlaubten eine spezifische und genaue Analyse der Bifidobakterienpopulation unter dem Einfluss eines Synbiotikums. / Background: Compared to formula-fed infants, breast-fed infants have a reduced incidence of gastrointestinal infections and atopic diseases. The health-promoting effect of breast milk is assumed to be partly mediated by the intestinal microbiota, which is characterized by a low diversity and a high proportion of bifidobacteria. Recent approaches in further development of infant formulae aim at promoting an intestinal microbiota similar to that of breast-fed infants. The supplementation of infant formula with probiotics (live microorganisms) or prebiotics (non-digestible carbohydrates, which serves as energy substrates for probiotic bacteria) could mimic the bifidogenic and antipathogenic, but also immunomodulating effect of breast milk. Due to various interactions with the gut microbiota and the immune system, the simultaneous administration of pro- and prebiotics (synbiotics) is focussed to have a synergistic effect. Objective and study design: In a randomized-controlled, clinical trial healthy full-term infants receiving an infant formula with synbiotic for the first three months of life were studied, whether an intestinal microbiota is induced, which is equivalent to that of breast-fed infants. The synbiotic consisted of Bifidobacterium animalis ssp. lactis CNCM I 3446 (previously known as B. lactis BB-12) and cow milk oligosaccharides. The study comprised two groups of infants receiving a starter formula with (SYN-group, n=21) or without supplement (KON-group, n=18). Breast-fed infants served as a reference (REF-group, n=23). In order to comprehensively characterize the bifidobacteria diversity at species level, quantitative real-time PCR (qPCR) assays based on the single-copy groEL as phylogenetic marker for the specific quantification of twelve bifidobacteria species in human feces were established and validated. Results: The supplemented formula was well tolerated and supported a healthy development; comparable anthropometric data of SYN- and REF-group. The synbiotic selectively stimulated the growth of lactobacilli and bifidobacteria. Lactobacilli levels were equivalent in SYN- and REF-group (9.07±0.32 versus 9.90±0.27 log10 cells/g feces DM [Mean±SEM]; p<0.0019; equivalence margin of 1 log10 cells/g feces DM) and higher than the KON-group (8.27±0.31 log10 cells/g feces DM [Mean±SEM]). The highest levels of bifidobacteria were observed in the SYN-group (11.54±0.05 versus 11.00±0.17 [REF-group] and 10.54±0.24 [KON-group] log10 cells/g feces DM [Mean±SEM]). The highest number of bifidobacteria species were obtained in the SYN-group (167 with [128 without] B. animalis in 56 fecal samples versus 98 and 93 in each of 51 fecal samples of the REF- and KON-group). Beside species, typically found in infants such as B. bifidum und B. breve, also species, which are characteristic for adults (B. adolescentis), were detected more often in the SYN-group than in the other study groups. Fecal pH was lower in the SYN- than in the KON-group 6.07±0.20 versus 6.45±0.17 [Mean±SEM]) and closer to that of breast-fed infants (5.29±0.12 [Mean±SEM]). Conclusion: In infants fed a starter formula supplemented with a synbiotic (CNCM I-3446 and cow milk oligosaccharides), composition of intestinal microbiota and fecal pH were closer to that of breast-fed infants. The groEL-based qPCR-assays, developed in this study, allowed a specific and accurate analysis of the bifidobacterial population in response to the synbiotic intake.

Diet is a major force influencing the intestinal microbiota. This is obvious from drastic changes in microbiota composition after a dietary alteration. Due to the complexity of the commensal microbiota and the high inter-individual variability, little is known about the bacterial response at the cellular level. The objective of this work was to identify mechanisms that enable gut bacteria to adapt to dietary factors. For this purpose, germ-free mice monoassociated with the commensal Escherichia coli K-12 strain MG1655 were fed three different diets over three weeks: a diet rich in starch, a diet rich in non-digestible lactose and a diet rich in casein. Two dimensional gel electrophoresis and electrospray tandem mass spectrometry were applied to identify differentially expressed proteins of E. coli recovered from small intestine and caecum of mice fed the lactose or casein diets in comparison with those of mice fed the starch diet. Selected differentially expressed bacterial proteins were characterised in vitro for their possible roles in bacterial adaptation to the various diets. Proteins belonging to the oxidative stress regulon oxyR such as alkyl hydroperoxide reductase subunit F (AhpF), DNA protection during starvation protein (Dps) and ferric uptake regulatory protein (Fur), which are required for E. coli’s oxidative stress response, were upregulated in E. coli of mice fed the lactose-rich diet. Reporter gene analysis revealed that not only oxidative stress but also carbohydrate-induced osmotic stress led to the OxyR-dependent expression of ahpCF and dps. Moreover, the growth of E. coli mutants lacking the ahpCF or oxyR genes was impaired in the presence of non-digestible sucrose. This indicates that some OxyR-dependent proteins are crucial for the adaptation of E. coli to osmotic stress conditions. In addition, the function of two so far poorly characterised E. coli proteins was analysed: 2 deoxy-D gluconate 3 dehydrogenase (KduD) was upregulated in intestinal E. coli of mice fed the lactose-rich diet and this enzyme and 5 keto 4 deoxyuronate isomerase (KduI) were downregulated on the casein-rich diet. Reporter gene analysis identified galacturonate and glucuronate as inducers of the kduD and kduI gene expression. Moreover, KduI was shown to facilitate the breakdown of these hexuronates, which are normally degraded by uronate isomerase (UxaC), altronate oxidoreductase (UxaB), altronate dehydratase (UxaA), mannonate oxidoreductase (UxuB) and mannonate dehydratase (UxuA), whose expression was repressed by osmotic stress. The growth of kduID-deficient E. coli on galacturonate or glucuronate was impaired in the presence of osmotic stress, suggesting KduI and KduD to compensate for the function of the regular hexuronate degrading enzymes under such conditions. This indicates a novel function of KduI and KduD in E. coli’s hexuronate metabolism. Promotion of the intracellular formation of hexuronates by lactose connects these in vitro observations with the induction of KduD on the lactose-rich diet. Taken together, this study demonstrates the crucial influence of osmotic stress on the gene expression of E. coli enzymes involved in stress response and metabolic processes. Therefore, the adaptation to diet-induced osmotic stress is a possible key factor for bacterial colonisation of the intestinal environment. / Sowohl Humanstudien als auch Untersuchungen an Tiermodellen haben gezeigt, dass die Ernährung einen entscheidenden Einfluss auf die Zusammensetzung der Darmmikrobiota hat. Aufgrund der Komplexität der Mikrobiota und der inter individuellen Unterschiede sind die zellulären Mechanismen, die dieser Beobachtung zugrunde liegen, jedoch weitgehend unbekannt. Das Ziel dieser Arbeit war deshalb, Anpassungsmechanismen von kommensalen Darmbakterien auf unterschiedliche Ernährungsfaktoren mittels eines simplifizierten Modells zu untersuchen. Dazu wurden keimfreie Mäuse mit Escherichia coli MG1655 besiedelt und drei Wochen mit einer stärkehaltigen, einer laktosehaltigen oder einer kaseinhaltigen Diät gefüttert. Mittels zwei dimensionaler Gelelektrophorese und Elektrospray Ionenfallen-Massenspektrometrie wurde das Proteom der intestinalen E. coli analysiert und differentiell exprimierte bakterielle Proteine in Abhängigkeit der gefütterten Diät identifiziert. Die Funktion einiger ausgewählter Proteine bei der Anpassung von E. coli auf die jeweilige Diät wurde im Folgenden in vitro untersucht. E. coli Proteine wie z.B. die Alkylhydroperoxid Reduktase Untereinheit F (AhpF), das DNA Bindeprotein Dps und der eisenabhängige Regulator Fur, deren Expression unter der Kontrolle des Transkriptionsregulators OxyR steht, wurden stärker exprimiert, wenn die Mäuse mit der laktosehaltigen Diät gefüttert wurden. Reportergenanalysen zeigten, dass nicht nur oxidativer Stress, sondern auch durch Kohlenhydrate ausgelöster osmotischer Stress zu einer OxyR abhängigen Expression der Gene ahpCF and dps führte. Weiterhin wiesen E. coli Mutanten mit einer Deletion der ahpCF oder oxyR Gene ein vermindertes Wachstum in Gegenwart von nicht fermentierbarer Saccharose auf. Das spricht dafür, dass OxyR abhängige Proteine eine wichtige Rolle bei der Anpassung von E. coli an osmotischen Stress spielen. Weiterhin wurde die Funktion von zwei bisher wenig charakterisierten E. coli Proteinen untersucht: die 2 Deoxy D Glukonate 3 Dehydrogenase (KduD) wurde im Darm von Mäusen, die mit der laktosehaltigen Diät gefüttert wurden, induziert, während dieses Protein und die 5 Keto 4 Deoxyuronate Isomerase (KduI) nach Fütterung der kaseinhaltigen Diät herunterreguliert wurden. Mittels Reportergenanalysen wurde gezeigt, dass Galakturonat und Glukuronat die kduD und kduI Expression induzierten. KduI begünstigte die Umsetzung dieser Hexuronate. In E. coli wird die Umsetzung von Galakturonat und Glukuronat typischerweise von den Enzymen Uronate Isomerase (UxaC), Altronate Oxidoreduktase (UxaB), Altronate Dehydratase (UxaA), Mannonate Oxidoreduktase (UxuB) und Mannonate Dehydratase (UxuA) katalysiert. Weitere Experimente verdeutlichten, dass osmotischer Stress die Expression der Gene uxaCA, uxaB und uxuAB verminderte. Darüber hinaus zeigten kduID defiziente E. coli Mutanten in Gegenwart von Galakturonat oder Glukuronat und durch Saccharose ausgelösten osmotischen Stress eine Verlangsamung des Wachstums. Das deutet darauf hin, dass KduI und KduD die durch osmotischen Stress bedingten Funktionseinschränkungen der regulären hexuronatabbauenden Enzyme kompensieren. Die beobachtete Bildung von intrazellulären Hexuronaten während des Laktosekatabolismus in vitro stellt eine Verbindung zu dem ursprünglichen Tierexperiment her und deutet darauf hin, dass der Ernährungsfaktor Laktose die Verfügbarkeit von Hexuronat für intestinale E. coli beeinflusst. Diese Studie weist somit den Einfluss von osmotischem Stress auf die Expression von OxyR abhängigen Genen, die für Stressantwortproteine sowie für metabolische Enzymen kodieren, in E. coli nach. Durch Nahrungsfaktoren entstandener osmotischer Stress stellt demnach einen entscheidenden Faktor für die bakterielle Kolonisation des Darmes dar.

Pienarūgščių bakterijų paieška ir jų identifikavimas migruojančių didžiųjų ančių (Anas platyrhynchos) žarnyne naudojant dalinių 16S rRNR geno sekų analizę ir kultivavimu paremtus metodus Klaidas VARNA Vilniaus Universiteto Ekologijos Institutas, Hidrobiontų Ekologijos ir Fiziologijos Laboratorija bei Populiacinės Genetikos Laboratorija, Akademijos-2, Vilnius-21, 08412, Lietuva. Šiame tyrime pavasarinių ir rudeninių didžiųjų ančių (Anas platyrhynchos) migrantų iš Nemuno deltos virškinamojo trakto pieno rūgšties bakterijų įvairovė buvo ištirta naudojant molekulinius metodus (polimerazės grandininės reakcijos amplifikacija ir dalinių 16S rRNR geno sekų sekvenavimas) ir kultivavimu paremtus metodus. Migruojančių didžiųjų ančių (Anas platyrhynchos) pieno rūgšties bakterijų paieška buvo atlikta pirmą kartą. Rudeniniai didžiųjų ančių migrantai plonojo žarnyno sienelėse (1.2×107 iki 2.1×107 k.f.v./g) ir jų turinyje (nuo 3.4×107 iki 1.1×108 k.f.v./g) turi didesnį pieno rūgšties bakterijų skaičių nei pavasariniai migrantai (atitinkamai nuo 3.2×106 iki 4.8×106 k.f.v./g ir nuo 1.0×107 iki 2.2×107 k.f.v./g). Tiek rudeninių tiek ir pavasarinių didžiųjų ančių migrantų plonojo žarnyno sienelėse ir jų turinyje dominavo kokinės pieno rūgšties bakterijų formos (atitinkamai 65% ir 83.5% bei 81.4% ir 91.6%), o lazdelių buvo mažiau (atitinkamai 35% ir 16.5% bei 18.6% ir 8.4%). Manoma, kad minėtus skirtumus įtakoja keli veiksniai: ilgai trunkanti migracija, perėjimo periodas, skirtingas maistas ir... [toliau žr. visą tekstą] / Identification of lactic acid bacteria in the migrant mallard ducks Anas platyrhynchos intestinal tract by partial 16S rRNA gene sequence analysis and using culture-based techniques Klaidas VARNA Institute of Ecology of Vilnius University, Laboratory of Hydrobionts Ecology and Physiology, Laboratory of Population Genetics, Akademijos-2, Vilnius-21, 08412, Lithuania. In this study the lactic acid bacteria diversity of the intestinal tract content of the vernal and autumnal migrant mallard ducks (Anas platyrhynchos) from Nemuno delta has been investigated by molecular methods: polymerase chain reaction amplification and sequencing of partial 16S rRNA genes and using culture-based techniques. The investigation of the lactic acid bacteria of the migrant mallard ducks has been performed the first time. Autumnal migrant mallard ducks in the small intestine walls (from 1.2×107 until 2.1×107 c.f.u./g) and in their content (from 3.4×107 until 1.1×108 c.f.u./g have the greatest number of the lactic acid bacteria then vernal migrants (respectively from 3.2×106 until 4.8×106 c.f.u./g and from 1.0×107 until 2.2×107 c.f.u./g). In the small intestine walls and in their content of the autumnal and vernal migrant mallard ducks, dominated cocci-shaped lactic acid bacteria (respectively 65% and 83.5%, 81.4% and 91.6%), whereas rod-shaped was under (respectively 35% and 16.5%, 18.6% and 8.4%). Supposedly, that these defferences determine some factors: a long migration, period of incubate... [to full text]

Pastaraisiais dešimtmečiais industrinėse, išsivysčiusiose Vakarų Europos ir Šiaurės Amerikos šalyse ypač išaugo lėtinėmis uždegiminėmis žarnų ligomis (UŽL) sergančių vaikų skaičius. UŽL etiopatogenezė nėra pilnai aiški, tačiau manoma, kad jų išsivystymą sąlygoja pakitęs imuninis atsakas į žarnyno bakterijų antigenų stimuliaciją genetiškai predisponuotiems individams. Genetiniai tyrimai parodė genų polimorfizmo reikšmę atpažįstant bakterijas (NOD2) bei jų įtaką tokiuose ląstelės mechanizmuose, kaip imunoreguliacija (IL23R, IL10) bei autofagija (ATG16L1, IRGM). Naujausių tyrimų, atliktų su UŽL sergančiais individais, duomenimis, pakitusi žarnyno bakterijų sudėtis sukelia imuninės sistemos stimuliaciją, epitelio funkcijos sutrikimą bei gleivinės pralaidumą, dėl ko išsivysto lėtinis žarnyno gleivinės uždegimas. Remiantis klinikinių, radiologinių, endoskopinių bei histologinių tyrimų duomenimis, išskiriamos dvi UŽL: opinis kolitas (OK) ir Krono liga (KRL). OK – lėtinis storosios žarnos uždegimas, kurio metu pažeidžiami paviršiniai, t. y. gleivinės ir pogleivio, žarnos sluoksniai. KRL atveju, uždegiminiai pakitimai apima ne tik paviršinius, bet ir giliuosius žarnos sienelės sluoksnius, kurie gali atsirasti bet kurioje žarnyno dalyje, tačiau dažniausiai stebimi plonosios žarnos galinėje bei storosios žarnos pradinėje dalyse. Neseniai atlikti epidemiologiniai tyrimai parodė, kad vaikų, sergančių UŽL, sergamumas ir paplitimas kito: Krono ligos susirgimų atvejų skaičius laipsniškai... [toliau žr. visą tekstą] / In recent decades the number of children with chronic inflammatory intestinal diseases (IBD) has increased in the industrialized developed countries of Western Europe and North America [Benchimol et al., 2011; Molodecky et al., 2012]. IBD pathogenesis is not completely clear, but it is though it evolves from changes in the immune response to antigen stimulation of intestine bacteria to genetically predisposed individuals [Xavier et al., 2008]. Genetic studies have shown the importance of genetic polymorphism in identifying of bacteria (NOD2) and their influence on cell mechanisms such as immune regulation and autophagy (IRGM, ATG16L1) [Travasso et al., 2009; Cooney et al., 2009]. According to the data of the recent studies with IBD, the changed composition of the intestinal bacteria causes immune stimulation, epithelial dysfunction, and mucosal permeability, as a result, chronic inflammation of the intestinal mucosa develops. Based on the data of clinical, radiological, endoscopic and histological studies, there are two IBD subtypes: ulcerative colitis (UC) and Crohn's disease (CD). UC is a chronic inflammation of the large intestine, when surface layers, i.e. mucosa and submucosa are affected. In CD inflammatory changes include not only the surface but also the deeper layers of the intestinal wall, which can occur in any part of the intestine. These changes are often seen in the end of the small intestine and in the initial part of the large intestine. Recent... [to full text]