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1.
Epidemiol Mikrobiol Imunol ; 72(2): 112-118, 2023.
Article in English | MEDLINE | ID: mdl-37344224

ABSTRACT

Since the beginning of the 21st century, a new discipline, microbiome science, has emerged as a key part of microbiology and related biomedical and ecological sciences. Microbiome science uses highly advanced molecular genetic and bioinformatic methods to study complex microbial communities. Unlike isolated microbes, microbial communities shaped by the environment, referred to as microbial consortia or microbiomes, follow their own laws that allow for significant functional specialization. The synthesis of multimethodology and multidisciplinary data enables microbiome science to move towards a holistic picture of the microbiome in an exceptionally effective way, but on the other hand, it burdens the field with terminological ambiguity of the key terms, which consequently need to be clearly codified in accordance with the international trends in the use of technical nomenclature. To this end, we present in our article the official position of the Czech Microbiome Society of the J. E. Purkyne Czech Medical Society on the use of appropriate Czech terms in both professional and general communication.


Subject(s)
Microbiota , Humans , Microbiota/genetics
2.
Ceska Gynekol ; 85(3): 206-213, 2020.
Article in English | MEDLINE | ID: mdl-33562975

ABSTRACT

OBJECTIVE: Review of current knowledge about particular neutrophil subsets and their role in preeclampsia. DESIGN: Review. SETTING: Institute of Immunology and Microbiology, First Faculty of Medicine Charles University and General University Hospital in Prague. INTRODUCTION: Preeclampsia represents one of the major complications of pregnancy with high mortality nowadays. Preeclampsia is a multifactorial disease and to this date, there has not been clear disease trigger identified. Throughout preeclampsia development, an increase in pathophysiological inflammatory response is being present. The induction of inflammation leads to higher number of migrating neutrophils. Current studies demonstrate that neutrophils are a rather heterogeneous population. Deregulation of the ratio between immunoregulatory subpopulations, including polymorphonuclear myeloid-derived suppressor cells, and proinflammatory neutrophil subpopulations could contribute to the induction of inflammatory environment at the feto-maternal interface and subsequently could promote development of pregnancy complications, such as preeclampsia. METHODS AND RESULTS: In this review, topic of preeclampsia is briefly introduced and a list of distinct neutrophil subsets published in literature is presented. CONCLUSION: Unravelling the role of abnormal neutrophil subpopulations migrating to the inflammatory environment of preeclamptic placentas and their role in preeclampsia development could help to identify possible therapeutic targets.


Subject(s)
Neutrophils , Pre-Eclampsia , Female , Humans , Placenta , Pregnancy
3.
Folia Biol (Praha) ; 65(5-6): 221-226, 2019.
Article in English | MEDLINE | ID: mdl-32362305

ABSTRACT

Due to the increasing incidence of allergic diseases, there is a strong need to identify a prognostic marker pointing to increased risk of allergy development allowing introduction of early preventive measures. Cord blood seems to be a good source for searching for such marker. The capacity of cord blood cells to respond to common allergens could point to increased predisposition to later allergy development. In our study, cytokines typical of Th1 (IFN-γ), Th2 (IL-5, IL-13) and Treg (IL-10) immune responses were followed at both the level of gene expression and cytokine secretion in cord blood cells of newborns of healthy mothers (children with relatively low risk of allergy development) and allergic mothers (children with relatively high risk of allergy development) stimulated by allergens (pollen from birch and timothy grass, house dust mite, ovalbumin). We have not observed any difference in the response of cord blood cells of neonates of healthy and allergic mothers to allergen in vitro. Both gene expression and secretion of cytokines in response to allergen stimulation were comparable with the unstimulated controls. It seems that early postnatal events will be more decisive for future allergy development than prenatal sensitization of the foetal immune system with allergen in utero in allergic mothers.


Subject(s)
Allergens/immunology , Hypersensitivity/immunology , Immunity , Mothers , Child , Cytokines/genetics , Cytokines/metabolism , Female , Fetal Blood/cytology , Gene Expression Regulation , Humans , Hypersensitivity/genetics , Infant, Newborn , Leukocytes, Mononuclear/metabolism
4.
Ceska Gynekol ; 82(5): 407-410, 2017.
Article in Czech | MEDLINE | ID: mdl-29020789

ABSTRACT

OBJECTIVE: To summarize available data concerning the role of maternal imunity and woman´s microbiome in the pathogenesis of preterm labor and their use in clinical practice. SETTING: Department of Obstetrics and Gynecology od the First Faculty of Medicine, Charles University in Prague, and General Teaching Hospital. DESIGN: Review article. METHODS: Compilation od published data from scientific literature. CONCLUSION: Preterm labor complicates approximately 10% of all pregnancies and represents a serious medical, social and economic problem. In the past, a lot of causes of preterm labor were discussed; infection, uteroplacental ischemia, decidual hemorrhage, uterine overdistension, cervical disease and maternal-fetal tolerance disorder were considered the most common. However, chronic inflammation seems to be the common pathogenic process underlying preterm labor, irrespective of the original stimulus. Currently, impaired maternal-fetal immunological tolerance represents most discussed topic. Growing scientific evidence suggests that the immune regulation of the maternal-fetal interface is the result of the coordinated interaction among maternal microbiota, trophoblast and maternal cellular components. From this view we understand preterm labor as a result of disruption of this process.


Subject(s)
Microbiota/immunology , Obstetric Labor, Premature/immunology , Pregnancy Complications, Infectious/microbiology , Premature Birth/microbiology , Female , Fetus , Humans , Pregnancy , Prenatal Care
5.
Epidemiol Mikrobiol Imunol ; 66(4): 163-172, 2017.
Article in Czech | MEDLINE | ID: mdl-29352802

ABSTRACT

Human alveolar echinococcosis (AE) is caused by larval stages of the tapeworm Echinococcus multilocularis. In the Czech Republic, screening tests to detect the specific infectious agent have been performed since 1998. The first AE cases were diagnosed in 2007, and until 2014, a total of 21 diseases were recorded. In accordance with radiological, histological, and/or PCR data, serological examinations of 699 individuals helped to reveal 15 additional AE cases in the period of 2015-2016. From the cumulative data for 1998-2016, it appears that of 2,695 patients examined, 36 (18 men and 18 women) were diagnosed with AE. Their age at diagnosis ranged from 20 to 82 years and was lower for women (mean 43.7, median 39.5) than for men (50.9 and 57.5, respectively), but the difference was not statistically significant. In the period of 2007-2016, the mean annual incidence rate was 0.034 cases/100 000 population. Our study indicates an ongoing increase in AE cases. The disease can be autochthonous in nature, as evidenced not only by some case history data but also by the detection of the larval stages in wild boar (Sus scrofa). AE risk to humans in the Czech Republic is discussed in the context of the known data on the presence of various parasite developmental stages in animals.


Subject(s)
Echinococcosis , Echinococcus multilocularis , Adult , Aged , Aged, 80 and over , Animals , Czech Republic , Echinococcosis/diagnosis , Echinococcosis/epidemiology , Echinococcosis/parasitology , Echinococcus multilocularis/genetics , Female , Humans , Incidence , Male , Middle Aged , Polymerase Chain Reaction , Sus scrofa/parasitology , Young Adult
6.
Benef Microbes ; 7(5): 639-648, 2016 Nov 30.
Article in English | MEDLINE | ID: mdl-27633175

ABSTRACT

Probiotics are believed to prevent or reduce allergy development but the mechanism of their beneficial effect is still poorly understood. Immune characteristics of regulatory T cells (Tregs) in peripheral blood of perinatally probiotic-supplemented children of allergic mothers (51 children), non-supplemented children of allergic mothers (42 children), and non-supplemented children of healthy mothers (28 children) were compared at the age of 6-7 years. A first dose of a probiotic Escherichia coli strain (E. coli O83:K24:H31) was administered within 2 days after the birth and then 12 times during the first months of life and children were followed longitudinally. Proportion and functional properties of Tregs were estimated by flow cytometry in relation to the children's allergy status. Proportion of Tregs in the peripheral blood of children suffering from allergy tends to be higher whereas median of fluorescence intensity (MFI) of FoxP3 was significantly decreased in allergic group. Intracellular presence of regulatory cytokine interleukin (IL)-10 was also lower in allergic children. Immune functions of Tregs reflected by both MFI of FoxP3 and IL-10 in the group of probiotic-supplemented children of allergic mothers were nearly comparable with children of healthy mothers while probiotic non-supplemented children of allergic mothers have decreased immune function of Tregs. Supplementation by probiotic E. coli strain decreases allergy incidence in high-risk children. In contrast to our expectation, proportion of Tregs has not been increased in probiotic supplemented children. Beneficial effect of probiotics on newborn immature immune system could be, at least partially, explained by the modulating immune function of Tregs. In summary, we detected increased proportion of Tregs in peripheral blood of allergic children, their functional properties were decreased in comparison with the Tregs of healthy children. A unifying hypothesis for these findings is that Treg numbers in allergic children are increased in order to compensate for decreased function.


Subject(s)
Cytokines/immunology , Escherichia coli , Hypersensitivity/prevention & control , Interleukin-10/immunology , Probiotics/administration & dosage , T-Lymphocytes, Regulatory/immunology , Child , Child, Preschool , Cytokines/blood , Female , Flow Cytometry , Humans , Infant , Infant, Newborn , Interleukin-10/blood , Male
7.
Folia Biol (Praha) ; 62(1): 26-33, 2016.
Article in English | MEDLINE | ID: mdl-27085007

ABSTRACT

Bird schistosomes parasitize mammals as non-specific hosts. Neurotropic Trichobilharzia regenti migrates extravasally via nervous tissue in experimentally infected mice. The majority of successfully penetrated larvae remain in the skin; the rest migrate through peripheral nerves to the spinal cord and brain. The potential of schistosomula to leave the skin and enter the central nervous system vary, and may be associated with Th1/Th2 polarization of the host cell immune response. The aim of the present study was to evaluate the impact of induced shift in polarization of cell immune response on the migration of T. regenti larvae in mammals. For this purpose, non-specifically immunomodulated mice were infected. The localization and abundance of schistosomula and associated histopathological changes were followed using routine histological techniques. Markers characterizing Th1 and Th2 systemic immune responses were followed using flow cytometry. The study revealed that the shift towards Th1 response at the time of infection correlates with the speed and intensity of schistosomula migration towards the brain and with the severity of accompanying pathologies. This indicates increased health risks associated with T. regenti infection for mammals (potentially including human) with previously modulated cell immune response that may occur under natural conditions, e.g. due to the exposure to another infectious agent.


Subject(s)
Schistosomatidae/immunology , Th1 Cells/immunology , Th2 Cells/immunology , Trematode Infections/immunology , Trematode Infections/parasitology , Animals , Brain/parasitology , Brain/pathology , Female , Flow Cytometry , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Receptors, Chemokine/metabolism
8.
J Synchrotron Radiat ; 22(2): 342-7, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25723935

ABSTRACT

A study of metallic brazing material for internally cooled optics is presented. The study shows the influence of the different material properties on the final quality of the bond in terms of diffracted wavefront distortion, i.e. enlargement of the rocking curve. By choosing the proper brazing material and applying the proper brazing conditions, the influence of the brazing material can be fully eliminated. Furthermore the degradation of some brazing material due to the extreme working conditions of the optics is presented. Measurement results from ESRF and KEK confirm the importance of the proper brazing material choice.

9.
Folia Biol (Praha) ; 60(2): 74-82, 2014.
Article in English | MEDLINE | ID: mdl-24785110

ABSTRACT

The incidence of allergic diseases is steadily increasing an urgent need to clarify the immunologic processes which occur early in life and signal an increased risk of possible future allergy development. The ratio and maturation state of DCs together with the cytokine environment are important in directing and modulating immune responses. The maturation state (presence of CD83) of cord blood monocyte-derived dendritic cells (moDCs) of 52 children of healthy mothers and 58 children of allergic mothers was estimated by flow cytometry. The capacity of moDCs to express genes for subunits of IL-12 family cytokines was monitored using real-time PCR and protein secretion in cell culture supernatants by ELISA. The percentage of CD83+ moDCs was significantly higher in the allergic group after LPS stimulation (43.11 ± 4.41) in comparison to the healthy group (24.85 ± 3.37). Significantly higher gene expression of subunits of IL-12 family members was observed in moDCs of children of allergic mothers, in comparison with children of healthy mothers. The differences were evident mainly after LPS stimulation of moDCs (healthy group: p19: 3.05 ± 1.24; p28: 14.8 ± 6.8; p35: 1.8 ± 0.6; p40: 8.0 ± 3.5; EBI3: 3.0 ± 1.2; allergic group: p19: 6.1 ± 2.7; p28: 61.4 ± 22.2; p35: 14.9 ± 6.5; p40: 36.4 ± 18.8; EBI3: 11.3 ± 3.2), with the exception of p28, whose expression was significantly higher in the allergic group even without stimulation (healthy group: 0.28 ± 0.12, allergic group: 0.87 ± 0.62). No significant difference between the healthy and allergic groups was found at the protein level. The observation of both increased presence of cell surface activation marker on moDCs and higher IL-12 family gene expression in LPS-stimulated moDCs of children of allergic mothers indicates a higher reactivity of these cells.


Subject(s)
Dendritic Cells/metabolism , Fetal Blood/cytology , Interleukin-12/metabolism , Antigens, CD , Cells, Cultured , Female , Flow Cytometry , Humans , Hypersensitivity/etiology , Hypersensitivity/metabolism , Immunoglobulins , Lipopolysaccharides/pharmacology , Male , Membrane Glycoproteins , Mothers , CD83 Antigen
10.
J Synchrotron Radiat ; 19(Pt 6): 1012-4, 2012 Nov.
Article in English | MEDLINE | ID: mdl-23093763

ABSTRACT

A proof-of-principle experiment of a novel harmonics separation optics for synchrotron facilities is presented. The harmonic separator is a Si crystal cut in an inclined geometry in which the impinging beam undergoes a diffractive-refractive effect owing to the dispersive nature of X-ray refraction. A polychromatic beam containing higher-order energies is spatially separated behind the separator into individual monochromatic diffraction spots. A synchrotron experiment at a bending-magnet beamline with 7 keV fundamental energy is presented. The spot of the third-order harmonic of 21 keV is deviated from the fundamental by 0.35 mm at a distance 1 m behind the device.

11.
Clin Exp Immunol ; 170(1): 10-7, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22943196

ABSTRACT

Allergy is one of the most common diseases with constantly increasing incidence. The identification of prognostic markers pointing to increased risk of allergy development is of importance. Cord blood represents a suitable source of cells for searching for such prognostic markers. In our previous work, we described the increased reactivity of cord blood cells of newborns of allergic mothers in comparison to newborns of healthy mothers, which raised the question of whether or not this was due to the impaired function of regulatory T cells (T(regs)) in high-risk children. Therefore, the proportion and functional properties of T(regs) in cord blood of children of healthy and allergic mothers were estimated by flow cytometry. The proportion of T(regs) [CD4(+)CD25(high)CD127(low) forkhead box protein 3 (FoxP3(+))] in cord blood of children of allergic mothers tends to be higher while, in contrast, the median of fluorescence intensity of FoxP3 was increased significantly in the healthy group. Intracellular presence of regulatory cytokines interleukin (IL)-10 and transforming growth factor (TGF)-beta was also higher in T(regs) of children of healthy mothers. Although we detected an increased proportion of T(regs) in cord blood of children of allergic mothers, the functional indicators (intracellular presence of regulatory cytokines IL-10 and TGF-beta, median of fluorescence intensity of FoxP3) of those T(regs) were lower in comparison to the healthy group. We can conclude that impaired function of T(regs) in cord blood of children of allergic mothers could be compensated partially by their increased number. Insufficient function of T(regs) could facilitate allergen sensitization in high-risk individuals after subsequent allergen encounter.


Subject(s)
Fetal Blood/immunology , Forkhead Transcription Factors/metabolism , Hypersensitivity/immunology , T-Lymphocytes, Regulatory/immunology , CD4 Antigens/metabolism , Case-Control Studies , Female , Fetal Blood/cytology , Fetal Blood/metabolism , Flow Cytometry , Forkhead Transcription Factors/immunology , Humans , Hypersensitivity/blood , Infant, Newborn , Interleukin-10/blood , Interleukin-10/metabolism , Interleukin-2 Receptor alpha Subunit/metabolism , Interleukin-7 Receptor alpha Subunit/metabolism , Pregnancy , T-Lymphocytes, Regulatory/metabolism , Transforming Growth Factor beta/blood , Transforming Growth Factor beta/metabolism
12.
Folia Microbiol (Praha) ; 55(5): 515-9, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20941589

ABSTRACT

To determine some early signs connected with the increased risk of future allergy development, gene expression and production of selected cytokines were tested in children of allergic mothers and compared with newborns of healthy mothers. Expression of IL-1ß, IL-2, IL-4, IL-8, IL-10, IL-13, IFN-γ, TNF-α, TGF-ß and EGF was tested in cord blood cells using real-time PCR and production of these cytokines was evaluated in cord sera by ELISA. Gene expression of IL-2, IL-4, IL-8, IFN-γ, IL-1ß, TNF-α and TGF-ß was decreased and that of IL-10, IL-13 and EGF increased in children of allergic mothers in comparison with those of healthy mothers. Significant differences in sera of healthy and allergic groups were only in IL-10 and EGF. Different relationship among serum cytokine levels reflects the fact that the cytokines are not produced only by blood cells. Significantly decreased production of EGF in newborns of allergic mothers could negatively influence maturation of mucosal membranes of these children and support thus their easier allergization. Allergic phenotype pointing to the bias to T(H)2 response and to possibly impaired intestine maturation was apparent already on the level of cord blood and could serve as a predictive sign of increased allergy risk.


Subject(s)
Cytokines/blood , Fetal Blood/cytology , Fetal Blood/metabolism , Hypersensitivity/blood , Cytokines/genetics , Cytokines/metabolism , Enzyme-Linked Immunosorbent Assay , Epidermal Growth Factor/blood , Epidermal Growth Factor/genetics , Epidermal Growth Factor/metabolism , Female , Gene Expression , Humans , Infant, Newborn , Interleukin-10/blood , Interleukin-10/genetics , Interleukin-10/metabolism , Pregnancy , Reverse Transcriptase Polymerase Chain Reaction
13.
J Synchrotron Radiat ; 17(1): 36-40, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20029109

ABSTRACT

Based on analytical formulae calculations and ray-tracing simulations a low-aberration focal spot with a high demagnification ratio was predicted for a diffractive-refractive crystal optics device with parabolic surfaces. Two Si(111) crystals with two precise parabolic-shaped grooves have been prepared and arranged in a dispersive position (+,-,-,+) with high asymmetry. Experimental testing of the device at beamline BM05 at the ESRF provided a focal spot size of 38.25 microm at a focal distance of 1.4 m for 7.31 keV. This is the first experiment with a parabolic-shaped groove; all previous experiments were performed with circular grooves which introduced extreme aberration broadening of the focal spot. The calculated and simulated focal size was 10.8 microm at a distance of 1.1 m at 7.31 keV. It is assumed that the difference between the measured and calculated/simulated focal spot size and focal distance is due to insufficient surface quality and to alignment imperfection.


Subject(s)
Artifacts , Lenses , Refractometry/instrumentation , Synchrotrons/instrumentation , Computer-Aided Design , Equipment Design , Equipment Failure Analysis , Reproducibility of Results , Scattering, Radiation , Sensitivity and Specificity , X-Rays
14.
J Synchrotron Radiat ; 15(Pt 6): 543-8, 2008 Nov.
Article in English | MEDLINE | ID: mdl-18955759

ABSTRACT

Rocking curves of micro-channel (MC) water-cooled monochromators are broadened by stresses introduced during fabrication and under X-ray thermal load. This is a problem which will be even more serious with the rise of the fourth-generation synchrotron sources, i.e. the free-electron lasers. The X-ray optics group at the Institute of Physics at the ASCR v.v.i. in Prague is designing, testing and, with company Polovodice a.s., fabricating novel internally water-cooled Si monochromators. Here three new micro-channel geometries are introduced which reduce rocking-curve enlargement owing to the fabrication to less than 2.5 microrad ( approximately 0.5 arcsec). All three MC designs show less rocking-curve enlargement and smoother topographic images. The designs also show better cooling efficiencies than the classical MC design in finite-element analysis calculations.


Subject(s)
Computer-Aided Design , Silicon/chemistry , Spectrum Analysis/instrumentation , Synchrotrons/instrumentation , Equipment Design , Equipment Failure Analysis , Miniaturization , Optical Devices , Surface Properties
15.
J Synchrotron Radiat ; 15(Pt 1): 8-11, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18097072

ABSTRACT

A simple variant of a Si internally cooled inclined X-ray monochromator of reasonable size is proposed. It has two inclined surfaces oriented into a V shape. This design substantially decreases the surface deformations introduced by radiation heat, and the size of the crystal is still feasible for a 50 mm broad impinging bending magnet or wiggler beam. The possibility of sagittal focusing of the diffracted beam is also discussed.

16.
J Synchrotron Radiat ; 13(Pt 5): 392-6, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16924135

ABSTRACT

The possibility of sagittally focusing synchrotron radiation using an asymmetric Laue crystal with profiled surfaces has been experimentally demonstrated for the first time. The sample was a Si single crystal with two parallel cylindrical holes of diameter 8 mm. The axes of the holes formed an angle of 7.95 degrees with the (111) diffracting planes and were arranged vertically with respect to the diffracting planes. 15.35 keV synchrotron radiation was diffracted in the space between the holes. The minimum thickness of this Laue crystal was 0.5 mm. The diffracted beam formed an angle of 0.55 degrees with the exit surface. The experiment was performed at beamline BM05 at the ESRF. The length of the beamline was not sufficiently long to detect the focus, but the experiment clearly showed that the diffracted beam was sagittally convergent.


Subject(s)
Lenses , Optics and Photonics , Synchrotrons , Crystallization , Equipment Design , Radiometry , Refractometry , Silicon/chemistry , X-Rays
17.
J Synchrotron Radiat ; 10(Pt 3): 233-5, 2003 May 01.
Article in English | MEDLINE | ID: mdl-12714753

ABSTRACT

The sagittal deviation of a Laue-diffracted X-ray beam caused by the inclination of an exit crystal surface with respect to an entrance crystal surface has been studied both theoretically and experimentally. The use of this effect for sagittal focusing of X-ray synchrotron radiation diffracted by a Laue crystal is suggested. The focusing is based on the refraction effect due to the parabolic profile of an exit or/and entrance surface. The crystal is not bent. In order to achieve a reasonable focusing distance, the crystal should be cut asymmetrically. The experiment was performed at beamline BM5 at the ESRF.

18.
J Synchrotron Radiat ; 8(Pt 6): 1200-2, 2001 Nov 01.
Article in English | MEDLINE | ID: mdl-11679772

ABSTRACT

When the surface of a single-crystal monochromator is not parallel to the diffracting crystallographic planes, the diffracted beam is generally deviated from the plane of diffraction and the angle between the diffracted beam and the diffracting planes is different from the angle between the incident beam and the diffracting planes. The angular diffraction regions for the incident and diffracted beams are also different. This is the manifestation of the refraction occurring during Bragg diffraction. Very simple formulae are presented which describe this situation in a general case (e.g. for a rotated-inclined X-ray monochromator). These formulae allow sagittally focusing monochromators for synchrotron radiation to be easily designed, based on X-ray diffraction-refraction phenomena. Some important properties of such types of monochromators are deduced.

19.
J Synchrotron Radiat ; 8(Pt 6): 1203-6, 2001 Nov 01.
Article in English | MEDLINE | ID: mdl-11679773

ABSTRACT

The possibility of concentrating a synchrotron X-ray beam using diffraction by a single crystal with a properly designed transverse groove on its surface, suggested earlier, has been studied experimentally. Here, the first experimental demonstration of this effect is reported, performed on beamline BM5 at the ESRF. The experimental result confirms the theoretical model.

20.
J Synchrotron Radiat ; 8(Pt 6): 1207-13, 2001 Nov 01.
Article in English | MEDLINE | ID: mdl-11679774

ABSTRACT

A very simple method of sagittal focusing of X-ray synchrotron radiation is presented. A special ray-tracing program which utilizes the diffraction-refraction effect is developed. It is demonstrated both by ray-tracing simulations and by an experiment whereby a reasonably good sagittal concentration of 8 keV synchrotron radiation may be achieved by diffraction on the walls of a cylindrical hole drilled into an Si crystal. The holes were drilled parallel to the (111) planes and their diameter, 1 mm, was chosen so that the focusing distance fits the geometrical arrangement of beamline BM5 at the ESRF. Two such crystals have been used in a dispersive and non-dispersive arrangement. The better result was achieved using the dispersive arrangement. The intensity at the centre of the focus is increased by five times with respect to unfocused radiation. Excellent agreement exists between the ray-tracing simulations and experimental results.

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