Synthesis and Characterization of New Boron Compounds Using Reaction of Diazonium Tetraphenylborate with Enaminoamides

A family of oxazaborines, diazaborinones, triazaborines, and triazaborinones was prepared by reaction of polarized ethylenes, such as β-enaminoamides, with 4-methylbenzenediazonium tetraphenylborates. The reaction conditions (stirring in CH₂Cl₂ at room temperature (Method A) or stirring with CH₃COONa in CH₂Cl₂ at room temperature (Method B) or refluxing in the CH₂Cl₂/toluene mixture (Method C)) controlled the formation and relative content of these compounds in the reaction mixtures from one to three products. Substituted oxazaborines gradually rearranged into diazaborinones at 250 °C. The prepared compounds were characterized by ¹H NMR, ¹³C NMR, IR, and UV–Vis spectroscopy, HRMS, or microanalysis. The structure of individual compounds was confirmed by ¹¹B NMR, ¹⁵N NMR, 1D NOESY, and X-ray analysis. The mechanism of reaction of enaminoamides with 4-methylbenzenediazonium tetraphenylborate was proposed.

Toxicokinetics of hydrophobic organic compounds in oligochaeta: A critical review

Toxicokinetic studies appertain to the fundamental research of soil bioavailability. However, the research outcomes of aspects influencing uptake and elimination of hydrophobic organic compounds have not been summarized so far. In our review, a recapitulation of available toxicokinetic data (i.e. experimental conditions, if the steady state was reached, uptake and elimination rate constants, and bioaccumulation factors) is presented in well-arranged tables. Further, toxicokinetic models are overviewed in the schematic form. In the review, the required information could be quickly found and/or the experimental gaps easily identified. Generally a little is known about the effects of soil properties other than soil organic matter. Limited or no data are available about soil treatment, food supply during laboratory exposure, and metabolization in oligochaeta. The impact of these factors might be important especially for arable soils with typically low organic matter content but high consequences on humans. Besides these circumstances, other uncertainties between published studies have been found. Firstly, the scientific results are provided in heterogenous units: bioaccumulation factors as well as the rate constants are reported in dry or wet weight of soil and earthworms. The steady state is another critical factor because the time to reach the equilibrium is influenced not only by soil and compound characteristics but for example also by aging. Nevertheless, toxicokinetic studies bring irreplaceable information about the real situation in soil and our review help to define missing knowledge and estimate the scientific priorities.

The Importance of Cancer-Associated Fibroblasts in the Pathogenesis of Head and Neck Cancers

BACKGROUND

Despite progress in anticancer therapies, head and neck squamous cell carcinoma (HNSCC) has still a low survival rate. Recent studies have shown that tumour stroma may play an important role in the pathogenesis of this malignant disease. Fibroblasts are a major component of the tumour microenvironment and may significantly influence HNSCC progression as indicated by the contribution they make to important hallmarks of cancer, such as inflammation, non-restricted growth, angiogenesis, invasion, metastasis, and therapy resistance. It is well known that tumour cells can confer a cancer-associated fibroblast (CAF) phenotype that supports the growth and dissemination of cancer cells. CAFs can stimulate cancer progression through cell-cell contacts and communication, remodelling of extracellular matrix, and production of many signal molecules and matrix metalloproteinases. Consequently, genetic changes in epithelial cells are probably not the only factor that drives HNSCC carcinogenesis. Non-genetic changes in the tumour stroma can also be significantly involved. Stress-induced signals can induce a multicellular program, creating a field of tissue that is predisposed to malignant transformation. The “field cancerization” concept represents a process of active evolution of intercellular interactions and feedback loops between tumour and stromal cells. This model paves the way to study cancer from a new perspective and identify new therapeutic targets.

PURPOSE

In this review, we discuss current knowledge about CAFs, such as their cellular origin, phenotypical plasticity and functional heterogeneity, and stress their contribution to HNSCC progression. This article was supported by the project AZV 16-29835A. The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers. Submitted: 18. 6. 2019 Accepted: 9. 9. 2019.

Uptake kinetics of four hydrophobic organic pollutants in the earthworm Eisenia andrei in aged laboratory-contaminated natural soils

Laboratory studies of pollutant uptake kinetics commonly start shortly after experimental soil contamination when it is not clear if the processes between soil and chemicals are equilibrated and stabilized. For instance, when the concentration in soil quickly decreases due to initial biodegradation, bioaccumulation may show a peak-shape accumulation curve instead of conventional first order kinetics with a plateau at the end. The results of such experiments with soil freshly contaminated in the laboratory are then hardly comparable to bioaccumulation observed in soils from historically contaminated sites. Therefore, our study focused on the uptake kinetics of four hydrophobic organic compounds (pyrene, lindane, p,p'-DDT and PCB 153) in two laboratory-contaminated natural soils with different soil properties (e.g. total organic carbon content of 1.6 and 9.3%) aged for 203 days to mimic long-term contamination. For pyrene, the results surprisingly showed peak-shape accumulation curves despite long aging. It seems compound biodegradation might be significant in aged soils when the conditions change (e.g. by distribution to the experimental vessels) and this should be also considered when testing historically contaminated soils. For lindane, longer aging seems to guarantee stability of the soil-compound-earthworm system and the steady state was reached after 5 days of exposure. Furthermore, although concentrations of p,p'-DDT and PCB 153 in earthworms after 11-15-day exposure did not statistically differ, which is a commonly-used indicator that a steady state was reached, they continuously increased until the end of the exposure. Therefore, despite the aging, longer exposure was probably needed to reach the true equilibrium between concentrations in earthworms and soil. In summary, aging does not warranty the conventional first order kinetic curve with the equilibrium at the end of the exposure but may have diverse effects for compounds with different environmental properties and should be taken into account in the bioaccumulation factor calculation and the risk assessment.

Fate and bioavailability of four conazole fungicides in twelve different arable soils - Effects of soil and pesticide properties

The objective of this study is to characterize changes in the fate, behaviour and bioavailability of four conazole fungicides - CFs (prochloraz - PRO, tebuconazole - TEB, epoxiconazole - EPO, flusilazole - FLU) in 12 diverse agricultural soils in complex microcosm systems consisting of agriculturally-used fluvisols, plants (Lactuca sativa), earthworms (Eisenia fetida) and passive samplers (SPME, Empore™ discs, silicone rubber). Due to great variability of the data and other methodological problems, the in-matrix passive samplers failed to be indicators of pore-water concentration and (bio)availability/(bio)accessibility of CFs. A dissipation of all CFs followed the first order kinetics (usually after initial lag phase) with large span of resulting half-lives (7-670 d) depending on soils and compounds. In many soils, the model revealed the ending plateau, which indicates the non-degradable or slowly-degradable residues. The half-lives and the residues were generally higher for EPO and FLU, than for PRO and TEB. Greater but slower total dissipation of CFs was observed in soils with higher percentage of organic matter. Earthworm concentrations were highest at first sampling time (14 days) and considerably decreased afterwards often resulting in PRO concentration below LOQ. Earthworm uptake was influenced by amount of organic matter and soil texture. Accumulation to lettuce roots was generally higher than to leaves and differed greatly among CFs. Concentration shoot to root ratios were generally the lowest for FLU (0.04) and highest for TEB (0.37). PRO was not detected in lettuce leaves during experiment. The study brings new results on fate and bioavailability of CFs in soils.

Uptake kinetics of pesticides chlorpyrifos and tebuconazole in the earthworm Eisenia andrei in two different soils

Agriculture is today indispensably connected with enormous use of pesticides. Despite tough regulation, their entrance into soil cannot be excluded and they might enter soil organisms and plants and continue further to terrestrial food chains. This study was conducted to investigate the bioaccumulation of two pesticides currently used in large amounts, the insecticide chlorpyrifos (CLP) and the fungicide tebuconazole (TBZ). Their detailed uptake kinetics in the model earthworm species Eisenia andrei were measured in two arable soils differing in organic carbon content (1.02 and 1.93% respectively). According to our results, a steady state was reached after 3-5 days for both pesticides and soils. The values of bioaccumulation factors calculated at the steady state ranged from 4.5 to 6.3 for CLP and 2.2-13.1 for TBZ. Bioaccumulation factors were also calculated as the ratio of uptake and elimination rate constants with results comparable with steady-state bioaccumulation factors. The results suggested that the degradation and bioaccumulation of tested compounds might be influenced by other factors than only total organic carbon (e.g. clay content). The lower K_oc and hydrophobicity of TBZ relative to CLP probably led to higher availability of TBZ through pore water exposure. On the other hand, CLP's higher hydrophobicity probably caused an increase in availability by its additional uptake via ingestion. To enable a proper ecological risk assessment of current pesticides in soils, it is necessary to accurately determine their bioaccumulation in soil invertebrates. We believe that our study not only brings such information for two specific pesticides but also addresses key methodological issues in this area.

Currently and recently used pesticides in Central European arable soils

Although large amounts of pesticides are used annually and a majority enters the soil to form short- or long-term residues, extensive soil surveys for currently used pesticides (CUPs) are scarce. To determine the status of CUPs' occurrence in arable land in Central Europe, 51 CUPs and 9 transformation products (TPs) were analysed in 75 arable soils in the Czech Republic (CR) several months after the last pesticide application. Moreover, two banned triazines (simazine and atrazine) and their TPs were analysed because of their frequent detection in CR waters. Multi-residue pesticide analysis on LC-MS/MS after soil QuEChERS extraction was used. The soils contained multiple pesticide residues frequently (e.g. 51% soils with ≥5 pesticides). The levels were also noticeable (e.g. 36% soils with ≥3 pesticides exceeding the threshold of 0.01mg/kg). After triazine herbicides (89% soils), conazole fungicides showed the second most frequent occurrence (73% soils) and also high levels (53% soils with total conazoles above 0.01mg/kg). Frequent occurrence was found also for chloroacetanilide TPs (25% of soils), fenpropidin (20%) and diflufenican (17%). With the exception of triazines' negative correlation to soil pH, no clear relationships were found between pesticide occurrence and soil properties. Association of simazine TPs with terbuthylazine and its target crops proved the frequent residues of this banned compound originate from terbuthylazine impurities. In contrast, frequent atrazine-2-hydroxy residue is probably a legacy of high atrazine usage in the past. The occurrence and levels of compounds were closely associated with their solubility, hydrophobicity and half-life. The results showed links to CR water-monitoring findings. This study represents the first extensive survey of multiple pesticide residues in Central European arable soils, including an insight into their relationships to site and pesticide properties.

The characterization and validation of 17β-estradiol binding aptamers

The rapid and sensitive detection of small molecules is garnering increasing importance, and aptamers show great promise in replacing expensive, elaborate detection platforms exploiting chromatographic separation or antibody-based assays. The characterization of aptamer interaction with small molecule targets is not facile, and there is a mature need for a rapid, high-throughput technique for the analysis of aptamer-small molecule kinetics and affinity. In this work we present methodologies for the evaluation of aptamer-small molecule interactions, using the aptamers reported against the steroid 17β-estradiol as a model system. Microscale thermophoresis, apta-PCR affinity assay and surface plasmon resonance were explored to evaluate the reported aptamers' binding properties in terms of affinity and specificity, and were demonstrated to be successfully applied to the analysis of aptamer-small molecule interactions.

Aptamer Lateral Flow Assays for Ultrasensitive Detection of β-Conglutin Combining Recombinase Polymerase Amplification and Tailed Primers

In this work, different methodologies were evaluated in search of robust, simple, rapid, ultrasensitive, and user-friendly lateral flow aptamer assays. In one approach, we developed a competitive based lateral flow aptamer assay, in which β-conglutin immobilized on the test line of a nitrocellulose membrane and β-conglutin in the test sample compete for binding to AuNP labeled aptamer. The control line exploits an immobilized DNA probe complementary to the labeled aptamer, forcing displacement of the aptamer from the β-conglutin-aptamer complex. In a second approach, the competition for aptamer binding takes place off-strip, and following competition, aptamer bound to the immobilized β-conglutin is eluted and used as a template for isothermal recombinase polymerase amplification, exploiting tailed primers, resulting in an amplicon of a duplex flanked by single stranded DNA tails. The amplicon is rapidly and quantitatively detected using a nucleic acid lateral flow with an immobilized capture probe and a gold nanoparticle labeled reporter probe. The competitive lateral flow is completed in just 5 min, achieving a detection limit of 55 pM (1.1 fmol), and the combined competitive-amplification lateral flow requires just 30 min, with a detection limit of 9 fM (0.17 amol).

β-Conglutin dual aptamers binding distinct aptatopes

An aptamer was previously selected against the anaphylactic allergen β-conglutin (β-CBA I), which was subsequently truncated to an 11-mer and the affinity improved by two orders of magnitude. The work reported here details the selection and characterisation of a second aptamer (β-CBA II) selected against a second aptatope on the β-conglutin target. The affinity of this second aptamer was similar to that of the 11-mer, and its affinity was confirmed by three different techniques at three independent laboratories. This β-CBA II aptamer in combination with the previously selected β-CBA I was then exploited to a dual-aptamer approach. The specific and simultaneous binding of the dual aptamer (β-CBA I and β-CBA II) to different sites of β-conglutin was confirmed using both microscale thermophoresis and surface plasmon resonance where β-CBA II serves as the primary capturing aptamer and β-CBA I or the truncated β-CBA I (11-mer) as the secondary signalling aptamer, which can be further exploited in enzyme-linked aptamer assays and aptasensors.

Effects of combined composting and vermicomposting of waste sludge on arsenic fate and bioavailability

Composting and vermicomposting are traditional processes for the treatment of sludge. During these processes, the humification of organic matter has a significant effect on the physicochemical form and distribution of heavy metals. In this study, industrial sludge (groundwater treatment waste) contaminated by arsenic (396 ± 1 mg kg(-1)) was used. Such sludge poses a significant challenge with respect to effective treatment. Composting, vermicomposting (with Eisenia fetida), and the combined approach of composting and vermicomposting were performed to determine the evolution of arsenic speciation, mobility and bioavailability. The composting/vermicomposting was done with sludge, horse manure, and grass in the ratios of 3:6:1. A solution of 0.1M NH4COOCH3 was used as a single extraction solvent for determination of the mobile arsenic pool and targeted arsenic species (As(III), As(V), monomethylarsenic acid - MMA(V), dimethylarsenic acid - DMA(V)). The analysis of arsenic in the extracts was carried out by means of HPLC-ICP-MS spectrometry. In addition, the earthworm species E. fetida was used for bioaccumulation tests that followed the compost and vermicompost processes. The obtained results indicate a reduction in arsenic mobility and bioavailability in all matured composts and vermicomposts. The combined process exhibited a greater effect than compost or vermicompost alone.

[Analysis of complications and clinical and pathologic factors in relation to the laparoscopic cholecystectomy]

INTRODUCTION

Laparoscopic cholecystectomy (LCHCE) is connected with a different spectrum of postoperative complications than classic cholecystectomy. The aim of this study was to analyse the complications and define their relation to some chosen clinical and pathological factors and their incidence.

MATERIAL AND METHODS

We included 1014 patients that were operated (laparoscopic or converted cholecystectomy) at the Department of Surgery, University Hospital in Pilsen between January 1st 2008 and December 31st 2011. All included patients were at least one year after cholecystectomy in the time of the realization of this study therefore we could analyse late complications. The group of patients included 351 men (34.6%) and 663 women (65.4%). The median age was 57 years (range: 8-87 years). We evaluated the following clinical and pathological factors: a histopathological diagnosis, early surgical and internal complications (with manifestation within 30 days after cholecystectomy) classified by the Clavien-Dindo score, incisional hernia as a late complication, conversion, perforation of the gallbladder wall, the duration of hospital stay, the age of patients and the use of drain. The results of the study were calculated with use of statistical tests: the test of population probability, the two-sample t-test, the ODDS ratio) and then were compared with published literature data.

RESULTS

Surgical and internal complications occurred in 138 patients (13.6%) within 30 postoperative days. The most common complication was connected with the wound - 92 patients (9.1%), then a hematoma in the gallbladder bed - 16 patients (1.6%) and a biliary leak - 16 patients (1,6%). The bile duct injury which needed a reoperation affected 3 patients (0.3%). The laparoscopic operation had to be converted in 77 cases (7.6%). Incisional hernia after the placing of trocars or in the scar after the laparotomy (in the case of conversion) occurred in 32 patients (3.16%) during one year after the cholecystectomy. The influence of the age of patients on the incidence and the spectrum of postoperative complications were proved as statistically significant. Postoperative complications were more common in the case of male gender. We found a correlation between the diagnosis and postoperative complications. Men with solitary cholecystolithiasis had more common incidence of hematoma in the gallbladder bed. A biliary leak occurred three times more often after the procedures with a gallbladder wall perforation. Three of four bile duct injuries occurred during the non-converted laparoscopic cholecystectomies.

CONCLUSION

Our study proved the influence of the age of patients, the histopathological diagnosis, conversion and the perforation of gallbladder wall on the incidence of postoperative complications after laparoscopic cholecystectomy. The incidence of bile duct injury, which is the most serious complication, in our group of patients is comparable with published literature.

A simple, enaminone-based approach to some bicyclic pyridazinium tetrafluoroborates

Easily obtainable cyclic enaminones (piperidin-2-ylidenealkanones) can be transformed into substituted bicyclic pyridazinium tetrafluoroborates upon treatment with corresponding diazonium salts. The transformation can be performed either in a one-pot way or in a two-step process with the isolation of single azo-coupled enaminone as the intermediate. The former method is superior. Under the optimized conditions, a number of pyridazinium salts substituted with both electron-donating and electron-withdrawing substituents was easily synthesized. A mechanism of the formation of the pyridazinium salts is suggested. A partial drawback is the possibility of the formation of a mixture of products when using a different diazonium salt in each step due to a reversibility of the azo coupling. This can be suppressed by using a more reactive diazonium salt before a less reactive one.

Comparison of different methods for generation of single-stranded DNA for SELEX processes

Single-stranded DNA (ssDNA) generation is a crucial step in several molecular biology applications, such as sequencing or DNA chip and microarray technology. Molecules of ssDNA also play a key role in the selection of ssDNA aptamers through Systematic Evolution of Ligands by EXponential enrichment (SELEX). With particular interest for this application, herein we present a comparative study of the most used methods for generation of ssDNA used in SELEX, such as asymmetric PCR, enzyme digestion and magnetic separation with streptavidin beads. In addition, we evaluate a new technique that combines asymmetric PCR and enzyme digestion with the aim to achieve the maximum efficiency in ssDNA generation. The methods studied were compared in terms of quality of ssDNA using electrophoretic analysis and generated ssDNA yields were quantitatively measured using an Enzyme-Linked OligoNucleotide Assay (ELONA).

[The use of IgG antibody avidity assays in the diagnosis of cytomegalovirus infection]

Human cytomegalovirus (CMV) is the most common cause of congenital infection. Primary CMV infection can lead to severe disease and complications in patients immunocompromised as a result of disease or therapy. IgG antibody avidity assays make it possible to differentiate between primary infection and reactivation of latent infection or reinfection. The study objective was to determine CMV IgG avidity by enzyme-linked immunosorbent assay (ELISA) with denaturation of IgG antibody binding to the antigen and by chemiluminiscent microparticle immunoassay (CMIA) on an Abbott Architect analyzer. Both methods yielded comparable CMV IgG avidity results. In some cases, the Abbott test was superior in reflecting IgG antibody maturation during primary infection to microplate ELISA using antigen-antibody complex dissociation by a denaturing agent.

Spatial feeding preferences of ornithophilic mosquitoes, blackflies and biting midges

The section of habitat used by particular bloodsucking insects when seeking bloodmeals may influence the spectrum of hosts to which they have access and consequently the diseases they transmit. The vertical distribution of ornithophilic bloodsucking Diptera (Culicidae, Simuliidae and Ceratopogonidae) was studied using bird-baited traps set at both ground and tree canopy levels. In total, 1240 mosquito females of eight species, 1201 biting midge females of 11 species, and 218 blackfly females of two species were captured during 2003-2005. Culex pipiens (L.) (Diptera: Culicidae) was found to prefer ground-level habitats, whereas Anopheles plumbeus (Stephens) (Diptera: Culicidae), biting midges [Culicoides spp. (Diptera: Ceratopogonidae)] and Eusimulium angustipes (Edwards) (Diptera: Simuliidae) preferred the canopy. The results of this study with regard to Cx. pipiens behaviour differ from those of most previous studies and may indicate different spatial feeding preferences in geographically separate populations. The occurrence of E. angustipes in the canopy is concordant with its role in the transmission of avian trypanosomes. These findings may be important for surveillance programmes focusing on ornithophilic Diptera which transmit various pathogenic agents.

[Tick-borne encephalitis in the East Bohemia Region and its microbiological diagnostic pitfalls]

AIM OF THE STUDY

The analysis of cases of tick-borne encephalitis (TBE) laboratory diagnosed at the Department of Virology of the Institute of Clinical Microbiology of the University Hospital in Hradec Králové in 2003-2006 and comparison of the data from 2003-2006, 1999-2002 and 1995-1998. Another objective was to compare two routinely used ELISA (enzyme-linked immunosorbent assay) diagnostic kits for TBE.

MATERIAL AND METHODS

The samples from 3284 patients tested by the Department of Virology of the University Hospital in Hradec Králové in 2003-2006 were analyzed. The detection of the specific IgM and IgG antibodies in serum and cerebrospinal fluid specimens was performed using two ELISA diagnostic kits (Euroimmun, Germany, and Test-Line Ltd, Clinical Diagnostics, Czech Republic). Non-specific reactivity of IgM antibodies was only analyzed in 2004-2006.

RESULTS

In 2003-2006, TBE was diagnosed in 163 patients of the University Hospital in Hradec Králové aged from 3.5 months to 80 years. The number was by 48 cases (29%) higher than that in 1995-1998 and by 36 cases (22%) higher than that in 1999-2002. TBE was confirmed in 94 males (57.7%) and 69 females (42.3%). More than half of the patients were aged above 41 years (94/163, i.e., 57.6 %) and 60 patients (37 %) were older than 51 years. A biphasic course of infection was observed in 93/136 cases (68.4%). As many as 101/136 patients (74 %) had a history of a tick bite, one patient reported the consumption of non-pasteurized milk. Thirty-eight (1.4 %) specimens showed non-specific reactivity of IgM antibodies. None of the cases showed cerebrospinal fluid reactivity in the absence of serum reactivity.

CONCLUSIONS

Increase in the diagnosed TBE cases was reported in 2003-2006 in the East Bohemia Region. It was due mainly to more severe clinical forms of TBE that were more frequent than the milder ones. The distribution of the confirmed TBE cases remained unchanged in terms of age and sex, but the seasonal peak moved from summer to autumn. ELISA proved suitable for use in the routine diagnosis of TBE. Both of the tested commercial kits are of good quality. Nevertheless, in view of possible non-specific reactivity of IgM antibodies, IgG antibodies need to be tested in both the first acute serum specimen and paired sera. The detection of antibodies in cerebrospinal fluid is unlikely to be of diagnostic benefit for TBE. Close cooperation between the attending physician and clinical microbiologist is crucial.

[Comparison of reactive oxygen species production in neat semen and washed spermatozoa]

OBJECTIVE

To determine Reactive Oxygen Species (ROS) production in neat semen and spermatozoa suspension using chemiluminescence and to examine correlation between both methods.

SUBJECT

Prospective laboratory study.

SETTING

Department of Obstetric and Gynecology, University Hospital, Olomouc.

METHODS

The study included fertile volunteers (FV, n = 17), men from infertile couples (NM, n = 19) and men with idiopathic infertility (NMI, n = 15). ROS levels were determined by the same method in neat and washed semen samples.

RESULTS

The ROS production in neat semen was lower than that in spermatozoa suspension. There was no significant diference in ROS production between volunteers and males from infertile couples. There was a significant correlation between log ROS in neat semen and in spermatozoa suspension in studied groups (FV r = 0.85, p = 1.5 x 10(-5); NM r = 0.76, p < 2 x 10(-4); NMI r = 0.75, p < 1.5 x 10(-3)).

CONCLUSIONS

Measurement of ROS in neat semen is simpler, faster and better reflecting the actual level of oxidative stress than the same measurement in spermatozoa suspension. The implementation of this method can complement the algorithm of diagnostics and treatment of male infertility and be helpful in selection of patients for antioxidant or antibiotic treatment.

Endophagy of biting midges attacking cavity-nesting birds

Feeding behaviour, host preferences and the spectrum of available hosts determine the role of vectors in pathogen transmission. Feeding preferences of blood-feeding Diptera depend on, among others factors, the willingness of flies to attack their hosts either in the open (exophagy) or in enclosed places (endophagy). As far as ornithophilic blood-feeding Diptera are concerned, the biting midges (Diptera: Ceratopogonidae) and blackflies (Diptera: Simuliidae) are generally considered to be strictly exophagous. We determined which blood-sucking Diptera enter nest cavities and feed on birds by placing sticky foil traps inside artificial nest boxes. A total of 667 females of eight species of biting midges of the genus Culicoides (Latreille, 1809) were captured on traps during 2006-2007, with Culicoides truncorum (Edwards, 1939) being the dominant species. DNA blood analyses of blood-engorged females proved that midges actually fed on birds nesting in the boxes. Three species were identified as endophagous: Culicoides truncorum, Culicoides pictipennis (Staeger, 1839), and Culicoides minutissimus (Zetterstedt, 1855). Our study represents the first evidence that ornithophilic biting midges are endophagous. The fact that we caught no blackflies in the bird boxes supports the exophagy of blackflies. We believe that our findings are important for surveillance programmes focusing on Diptera that transmit various bird pathogens.

[Oxidative stress in diagnosis and treatment of idiopathic male infertility]

OBJECTIVE

To summarize available data concerning reactive oxygen species in sperm physiology and male infertility.

DESIGN

Review article.

SETTING

Dept. of Obstetrics and Gynecology, Faculty of Medicine and Dentistry, Palacky University and University Hospital Olomouc.

METHODS

Compilation of published data from scientific literature.

CONCLUSIONS

The article describes the importance of reactive oxygen species and their role in male reproductive health.

[Lycopene therapy in male infertility]

OBJECTIVE

To summarize available data concerning lycopene and male infertility treatment.

DESIGN

Review article.

SETTING

Dept. of Obstetrics and Gynecology, University Hospital Olomouc.

METHODS

Compilation of published data from scientific literature.

CONCLUSIONS

The article describes occurrence, biochemistry, metabolism of lycopene and its role in male reproductive health.

Coordination compounds based on 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid

Syntheses of 2,6-bis[((3S)-3-(methoxycarbonyl)-1,2,3,4-tetrahydroisoquinolin-2-yl)carbonyl]pyridine and its coordination compounds with Cu2+, Co2+, Co3+, or Fe3+ are described. By means of 1H- and 13C-NMR spectra it was proved that 2,6-bis[((3S)-3-(methoxycarbonyl)-1,2,3,4-tetrahydroisoquinolin-2-yl)carbonyl]pyridine as well as its coordination compound with Co3+ exist in the form of a mixture of three conformers, differing in the conformations at the two amide groups present. The prepared coordination compounds were tested in the enantioselective catalysis of the nitroaldol addition of nitromethane with 2-nitrobenzaldehyde or 4-nitrobenzaldehyde, and in the Michael addition of ethyl 2-oxocyclohexanecarboxylate to but-3-en-2-one.

Genetics of susceptibility to leishmaniasis in mice: four novel loci and functional heterogeneity of gene effects

Symptoms of human leishmaniasis range from subclinical to extensive systemic disease with splenomegaly, hepatomegaly, skin lesions, anemia and hyperglobulinemia, but the basis of this variation is unknown. Association of progression of the disease with Th2 lymphocyte response was reported in mice but not in humans. As most genetic studies in Leishmania major (L. major)-infected mice were restricted to skin lesions, we analyzed the symptomatology of leishmaniasis in mice by monitoring skin lesions, hepatomegaly, splenomegaly and seven immunological parameters. We detected and mapped 17 Leishmania major response (Lmr) gene loci that control the symptoms of infection. Surprisingly, the individual Lmr loci control 13 different combinations of pathological and immunological symptoms. Seven loci control both pathological and immunological parameters, 10 influence immunological parameters only. Moreover, the genetics of clinical symptoms is also very heterogeneous: loci Lmr13 and Lmr4 determine skin lesions only, Lmr5 and Lmr10 skin lesions and splenomegaly, Lmr14 and Lmr3 splenomegaly and hepatomegaly, Lmr3 (weakly) skin lesions, and Lmr15 hepatomegaly only. Only two immunological parameters, IgE and interferon-gamma serum levels, correlate partly with clinical manifestations. These findings extend the paradigm for the genetics of host response to infection to include numerous genes, each controlling a different set of organ-specific and systemic effects.

Synthesis and structure of some azo coupled cyclic beta-enaminones

The reaction of 3-phenylaminocyclopent-2-en-1-one with 4-methyl, 4-methoxy and 4-chlorobenzenediazonium tetrafluoroborates was used to prepare the azo coupling products 3a-c. It was found that these compounds are present in both CDCl(3) solution and solid phase practically exclusively as (E)-3-phenylamino-2-(4-subst.phenyldiazenyl)cyclopent-2-en-1-ones with N--H...N intramolecular hydrogen bond. The substitution of the phenyl residue of the diazonium salt has no effect on the position of the tautomeric equilibrium. On the other hand, the compounds 4a, b formed by the reaction of 3-phenylamino-1H-inden-1-one with 4-methylbenzene- or benzenediazonium tetrafluoroborates exist in CDCl(3) solution and in solid phase as hydrazone compounds. In the solution they occur as a mixture of three forms, out of which two were identified as E/Z isomers with different types of hydrogen bonds. Compound 5 formed by the reaction of 3-amino-5,5-dimethylcyclohex-2-en-1-one with 4-methoxybenzenediazonium tetrafluoroborate is converted into a stable hydrochloride 5.HCl on standing in CHCl(3) solution; this product exhibits a high degree of delocalization of the positive charge. Its structure was studied by means of X-ray.

[EmbryoGlue the transfer medium with hyaluronan in the IVF+ET program]

OBJECTIVE

To assess, if the replacement of serum albumin by recombinant human albumin and hyaluronan in EmbryoGlue transfer medium effects embryo implantation within IVF+ET programme.

DESIGN

A prospective study.

SETTING

Department of Obstetric and Gynecology, University Hospital, Olomouc.

METHODS

297 IVF cycles with the embryotransfer (ET) were evaluated. The patients were divided into 2 groups according to the type of transfer medium (culture medium; G2.2, n = 112 and the transfer medium EmbyoGlue (EG) n = 185) and to three subgroups according to the age of the patients (< 30, 30-38, > 38). In both groups the following entry parameters were compared: average age, number of oocytes obtained, fertilization rate (FR), number of frozen embryos, number of transferred embryos. The outcome parameters compared were: pregnancy rate (PR), implantation rate (IR), abortions (AB) and the number of multiple pregnancies.

RESULTS

In the group of patients up to 30 (EG = 72 vs. G2.2 = 51) and over 38 years of age EG = 18 vs. G2.2 = 18) no differences in input and output parameters have been discovered, while in the group of patients between 30 and 38 years of age (EG = 94 vs. G2.2 = 44) the results of EG group embryo implantation have been improved significantly (IR 27.7% vs. 153%, p < 0.01). No differences in any other output parameters have been encountered (PR 43.6% vs. 39.5%, AB 7.3% vs. 11.7%).

CONCLUSION

Human serum albumin can be replaced by hyaluronan as a sole macromolecule in a human embryo transfer medium and by recombinant human albumin, without reduction of pregnancy rate (PR) and implantation rate (IR). Not only similar results were achieved in EG medium compared to currently used G2.2 medium, but in the group of 30-38 year old patients a statistically significant positive influence of EG on the implantation of embryos has been observed.

[Embryo quality evaluation according to the speed of the first cleavage after IntraCytoplasmic Sperm Injection (ICSI)]

OBJECTIVE

To evaluate morphological parameters of embryos obtained in the process of ICSI.

DESIGN

A prospective study.

SETTING

Centre of Assisted Reproduction, Dept. of Obstetrics and Gynecology, Palacký University Medical School, Olomouc.

METHODS

In the present study 1116 embryos developing after ICSI (IntraCytoplasmic Sperm Injection) procedure in the period of 2001-2004 were evaluated. The beginning of the mitotic cleavage was assessed within the interval of 22-27 hours after insemination. The embryos were divided into three groups according to the speed of their division as Early Cleavage (EC) embryos, where two blastomeres were present at the time of assessment, Break Down ProNuclei stage (BDPN) where the pronuclei had already disappeared, and ProNuclei (PN) embryos, where both pronuclei were still present. In these groups the degree of fragmentation was evaluated on day two of cultivation and embryos were divided into four categories as: A--regular blastomeres, without fragmentation, B--irregular blastomeres or fragmentation below 30%, C--fragmentation 30-50%, D--fragmentation above 50%. The speed of further cleavage and average number of blastomeres were evaluated on day two and three of cultivation. Statistical analysis was preformed at the Palacky University Computer Centre. The chi2 test and t-test for independent samples were used.

RESULTS

EC embryos were found in 37.4%, BDPN in 33.1% and PN in 29.5%. The degree of fragmentation between evaluated groups of embryos were statistically significant (p = 0.000). EC embryos were less fragmented (p = 0.000), had more blastomeres at the time of evaluation (p = 0.000) and their speed of cleavage was faster (p = 0.000). The cleavage of EC embryos was faster in comparison with the PN group (p = 0.000), but there were no significant differences between the EC and BDPN groups on day two of cultivation. On day three significant differences were found also between the EC and BDPN groups (p = 0.000). The embryonic developmental arrest was found only in PN embryos.

CONCLUSION

The speed of the first cell cleavage is a useful additional criterion for the embryo selection for embryotransfer. EC embryos usually have better morphology and more blastomeres than the BPDN and PN ones.

[Embryo quality evaluation according to the speed of the first cleavage after conventional IVF]

OBJECTIVE

To evaluate morphological parametres of embryos obtained in the process of conventional IVF.

DESIGN

A prospective study.

SETTING

Centre of Assisted Reproduction, Dept. of Obstetrics and Gynecology, Palacký University Medical School, Olomouc.

METHODS

In the present study 549 embryos developing after conventional IVF in the period of 2001-2004 were evaluated. The beginning of the mitotic cleavage was assessed within the interval of 24 - 27 hours after insemination. The embryos were divided into three groups according to the speed of their division as early cleavage (EC) embryos, where two blastomeres were present at the time of assessment, break down pronuclei stage (BDPN) where the pronuclei had already disappeared, and pronuclei (PN) embryos, where both pronuclei were still present. In these groups the degree of fragmentation was evaluated on day two of cultivation and embryos were divided into four categories as: A - with regular blastomeres, without fragmentation, B - with irregular blastomeres or with fragmentation below 30%, C - with fragmentation 30-50%, D - with fragmentation above 50%. The speed of further cleavage and average number of blastomeres were evaluated on days two and three of cultivation. Statistical analysis was preformed in the Palacký University Computer Centre. The chi-square test and t test for independent samples were used.

RESULTS

EC embryos were found in 45.5%, BDPN in 33.5% and PN in 21.0%. EC embryos were less fragmented (p = 0.000), had more blastomeres at the time of evaluation (p = 0.000) and their speed of cleavage was faster (p = 0.000). The cleavage of EC embryos was faster in comparisson with the PN group (p = 0.000), but there were no significant differences between the EC and BDPN groups on day two of cultivation. On day three significant difference was found also between the EC and BDPN groups (p = 0.000).

CONCLUSION

The speed of the first cell cleavage is a useful additional criterion for the embryo selection for ET. EC embryos usually have better morphology and more blastomeres that the BPDN and PN ones.

[Prevention of multiple pregnancy after IVF/ICSI by elective single embryo transfer--pilot study]

OBJECTIVE

To reduce the number of multiple pregnancies after IVF/ICSI treatment by an elective single embryo transfer, without significant reduction of pregnancy rate (PR).

DESIGN

A pilot study.

SETTING

Department of Obstetrics and Gynecology, University Hospital, Olomouc.

METHODS

The patients were devided into the three groups according to number and quality of transferred embryos: elective Single EmbryoTransfer (eSET, n = 14), Single EmbryoTransfer (SET, n = 21), and Double EmbryoTransfer--control group (DET, n = 85). After 3 days of cultivation the embryos were transferred. In all groups the following parameters were compared: age of the patient, number of oocytes obtained, fertilization rate, number of frozen embryos, pregnancy rate (PR), implantation rate (IR), abortions (AB) and the number of multiple pregnancy.

RESULTS

In eSET group PR and (or IR) was 42.8%, in SET group PR and (or IR) was 19%. There were no monozygotic twins in these groups. In DET group PR was 40.7% and IR 25.9%. Nine of these 33 pregnancies were twins (27%). Because of small number of the patients detailed statistical analyses were not performed.

CONCLUSION

An elective transfer of one "TOP" embryo can reduce the number of multiple pregnancies without significant decrease of pregnancy rate.

[The analysis of preliminary spermatological parameters in potential donors of semen]

OBJECTIVE

To contribute to the contemporary discussion on the male factor infertility through the evaluation of the basic spermatological parameters in men recruiting for semen donation.

DESIGN

A retrospective demographic study.

SETTING

Dept. of Obstetrics and Gynaecology, Dept. of Biology, Faculty of Medicine, Palacký University, Olomouc.

METHODS

A total of 108 men aged 18 to 35 years came to the preliminary examination for the potential semen donors between January 2000 and April 2004. Spermatological analysis of the fresh ejaculates obtained by masturbation was performed according to WHO guidelines. The following parameters were evaluated: the volume of ejaculate, sperm concentration and total percent motility.

RESULTS

Normospermia was found in only 46 men (42.6%). Three males (2.8%) were azoospermic. The most frequent problem was asthenospermia, which was documented in 49 (46.6%) men.

CONCLUSION

The analysis of the obtained data may suggest a marked semen quality decline in the Czech male population. In our opinion, further multicentric epidemiological studies concerning fertility potential in Czech male population seem highly needed.

[Sonographic evaluation of endometrial preparation with oral estrogen-progesterone substitution before cryogenic embryo transfer]

OBJECTIVE

To compare the changes of sonographic features of endometrium throughout natural and artificial cycles in which oral estrogen-progesterone substitution were used in the same group of patients and discuss their clinical significance.

DESIGN

A prospective study.

SETTING

Dept. of Obstetrics and Gynaecology, University Hospital, Olomouc.

METHODS

In 24 women with regular menstrual cycle ovulation was detected (LH, sonography) and the following sonographic features: endometrial thickness, echogenity and pulsatility index (PI) of uterine artery were evaluated in the late proliferative, early and mid secretory phase. The same sonographic examination was performed in the artificial cycle with oral estrogen-progesterone substitution used for endometrial preparation for transfer of cryopreserved-thawed embryos.

RESULTS

In the late proliferative phase of the natural cycle the thickness of endometrium was higher than in the arteficial cycle (p=0.05). Triple-line echogenity prevailed in both cycles. The PI in natural cycle was lower (p=0.01) on the side of the growing Graafian follicle compared to the other side and lower (p=0.05) than in the artificial cycle. In the secretory phase there were no differences in endometrial thickness within cycles. Homogenous hyperechoic endometrium prevailed in both cycles and the lowest PI was found on the 7th day both after ovulation and after initiation of progesterone substitution.

CONCLUSION

Progesterone addition after endometrial preparation with estrogen should be instituted when the endometrium thickness reached at least 9mm and isoechoic or triple line echogenity is found.

[Efficiency of cryoembryotransfer using embryos frozen in the pronuclear stage]

OBJECTIVE

To evaluate results of cryoembryotransfers in cycles with estrogen-progestin preparation of the endometrium.

DESIGN

Prospective study.

SETTING

Centre of Assisted Reproduction, Dept. of Obstetrics and Gynecology, Palacký University Medical School, Olomouc.

METHODS

The study included 51 patients in whom in the period of January to August 2003 altogether 42 cycles the embryotransfer with frozen and thawed embryos were performed. The embryos for cryopreservation were obtained in the classical IVF (n = 21) or ICSI (n = 30) cycles and were cryopreserved in the pronuclear stage (PN). The storage interval varied from 3 months to 5 years. The endometrial preparation was performed in all cycles with oral estrogen--progestin substitution. Embryos in the PN stage were examined for survival (rate of intact embryos after thawing) and progress of their further development. Endometrial thickness, number of transferred embryos, pregnancy rate (PR), implantation rate (IR) and abortions (AB) were evaluated as outcome parameters.

RESULTS

A total of 210 thawed embryos were evaluated. Survival was 79% without regard to the method of fertilization. For 42 cryoembryotransfers 131 embryos (62%) in 6 to 10 blastomeres after 48 hours cultivation in G 1.2 and G 2.2 fy Vitrolife were selected. Further development was more regular in embryos obtained in classical IVF cycles, where 41% of the embryos were in 4 cells stage after 24 hours of cultivation and 36% of the embryos were in 8 cells stage after 48 hours while after ICSI 32% 4 cells embryos and 26% 8 cells embryos respectively. Endometrial thickness in the day of transfer in all patients was 10.9 +/- 1.3 mm, the average number of transferred embryos was 2.4 embryos/transfer, PR was 28.5 (IVF 42.9% and ICSI 20.7%), IR 12.0% (IVF 13.0% and ICSI 11.3%) and AB 41.6% (IVF 33.3% and ICSI 50.0%).

CONCLUSION

Improvement of cryopreservation procedures, freezing of embryos in the pronuclear stage and last but not least the optimal endometrial preparation can positively influence the cumulative efficiency of assisted reproduction.

[Effect of early cleavage of embryos after intracytoplasmic sperm injection (ICSI) into oocytes on results of fertilization in vitro (IVF) and embryo transfer (ET)]

OBJECTIVE

To evaluate the influence of early cleavage in embryos obtained using ICSI on the success rate of IVF-ET.

DESIGN

A prospective study.

SETTING

Centre of Assisted Reproduction, Department of Obstetrics and Gynecology, Medical Faculty, Palacký University, Olomouc.

METHODS

The rate of the first cleavage of embryos was checked between 23 to 26 hours after ICSI in 115 cycles IVF-ET. "Early Cleavage" (EC) embryos which were already cleaved were cultivated separately from the "slow" (No Early Cleavage, NEC) embryos. After 3 days cultivation, no more than three 6- to 8-cell embryos were transferred. Only EC embryos were transferred in 43 cycles and only NEC embryos were transferred also in 43 cycles. The remaining 29 cycles, where both EC and NEC embryos had to be transferred, were not evaluated. In both groups the following entry parameters were compared: age of the patient, number of fertilized oocytes, fertilization rate (FR), number of frozen and evaluated embryos, number of EC embryos recorded and number of transferred embryos. The outcome parameters compared were: pregnancy rate (PR), number of gestational sacs with heart beats per number of transferred embryos (implantation rate, IR), abortions (AB) and the frequency of multiple pregnancy. Statistical evaluation was performed by t-test, chi 2 test and by Sheffe analysis.

RESULTS

EC embryos were found in 57% of cycles (n = 66) after ICSI. Early cleavage was observed in 198 of 563 embryos (35%). Among entry parameters the only statistically significant differences (P < 0.05) were found in the number of retrieved oocytes as well as in the ratio of frozen embryos which were higher in the cycles with the transfer of only EC embryos. FR was the same (74%) in both types of transfer. Outcome parameters in the transfer of only EC versus NEC embryos were higher in PR (40% vs. 33%), about equal in IR (27% vs. 25%) and lower in AB (2% vs. 5%). Moreover, multiple pregnancies were less frequent in the transfer of only EC embryos: 65% of singleton pregnancy, 35% of twins and no triplet versus 36%, 57% and 7%, resp., in the transfer of only NEC embryos. The differences in outcome parameters are not statistically significant (P > 0.05) because of small numbers.

CONCLUSION

The speed of the first cell cleavage is a useful additional criterion for better evaluation of quality and viability of embryos.

Trypanosoma avium: experimental transmission from black flies to canaries

Trypanosomes identified as Trypanosoma avium were found in the ornithophilic black flies ( Eusimulium latipes) attacking buzzard nestlings ( Buteo buteo). Parasites formed plugs and rosettes in the hindgut of the vector and were attached on the cuticular lining of the black fly anterior intestine (ileum) by hemidesmosome-like plaques. Hindgut stages from infected black flies were experimentally transmitted into canaries ( Serinus canaria) by ingestion of vectors and by contamination of host conjunctiva. This is the first clear evidence of such transmission in avian trypanosomes. Parasites survived in peripheral blood of birds at the least 10 months. In contrast to the direct inoculation of insect stages, parasites from culture failed to produce infection in experimental birds; this has consequences for laboratory studies of host susceptibility and transmission.

[Early cleavage embryos and their effect on the results of standard in vitro fertilization]

OBJECTIVE

To assess if early cleavage embryo is an additional indicator of embryo quality that could be used to increase the efficiency of IVF and ET.

DESIGN

A prospective study.

SETTING

Centre for Assisted Reproduction, Department of Gynecology and Obstetrics, Medical Faculty, Palacký University, University Hospital, Olomouc.

METHODS

The study evaluates 62 cycles of conventional IVF in our Centre during 2001 to 2002. All embryos were observed for the presence or absence of "early cleavage" (EC), i.e. with completed first mitotic division 25 to 26 hours after insemination. The EC embryos were cultivated separately from the so called "late cleavage" or no early cleavage (NEC) embryos. After the three-day cultivation a maximum of three embryos were transferred in 6-8 cells stage. EC embryos were transferred in 28 cycles, NEC embryos in 18 cycles. The remaining 16 patients with "combined" transfer of EC + NEC embryos were excluded from the evaluation. The following parameters have been compared: age, number of fertilized oocytes, fertilization rate (FR), number of cryopreserved embryos, number of embryos assessed for EC, number of EC embryos found, number of transferred embryos, pregnancy rate (PR), implantation rate (IR), spontaneous abortions (AB). Statistical analysis was performed by Student's t-test, chi 2 test and Sheffe analysis.

RESULTS

EC embryos were found in 71% of conventional IVF (n = 44). There were no significant differences in the entry parameters (age, number of fertilized and fertilizing oocytes, number of cryopreserved, assessed and transferred embryos) between the group with EC embryos versus the group with NEC embryos. When EC embryos were transferred, the following parameters were higher: PR (61% vs. 56%), IR (38% vs. 33%), compared to NEC group, while pregnancy loss was lower after EC (4% vs. 11%) compared to NEC. Due to small numbers in the subgroups the results, though suggestive, are not statistically significant (p > 0.05).

CONCLUSIONS

The assessment of early cleavage embryo is one of the criteria for evaluation and selection of suitable embryos prior to transfer which could help in the process of selection to choose the best embryos between embryos of the same morphology on the day of transfer.

[Multiple pregnancy--a significant complication of in vitro fertilization protocols]

OBJECTIVE

To evaluate the history of pregnancies after IVF-ET, to define multiple pregnancy risk factors.

DESIGN

A retrospective analysis of the period of 1992-2000.

SETTING

Department of Gynecology and Obstetrics, University Hospital, Palacký University, Olomouc.

METHODS

343 pregnancies were evaluated, divided into 4 groups according to the patients' ages: < or = 29 yrs. (n = 150), 30-34 yrs. (n = 122), 35-39 yrs. (n = 66), > or = 40 yrs. (n = 5). The number of transferred embryos and frequency of pregnancies in relation to the patient' ages were compared as well as the multiple pregnancy and spontaneous abortion rates. The dependence of preterm labour rate, foetus weight and the incidence of operative delivery on the frequency of pregnancies were evaluated (n = 276). The data were analysed using the chi 2 and Sheffe tests.

RESULTS

Three or four transferred embryos markedly increase the number of multiple pregnancies (P < 0.01). No relation to the patient's ages was found. An increased incidence of operative deliveries (P < 0.01) as well as preterm deliveries (P < 0.05) in multiple pregnancies was found.

CONCLUSIONS

The number of transferred embryos is the most important risk factor for multiple pregnancy development. It is recommended to decrease the number of transferred embryos to two or one per ET.

[Celiac disease and fertility disorders in women]

OBJECTIVE

To determine incidence of subclinical forms of celiac disease in women with decreased fertility.

DESIGN

Screening test.

SETTING

Department of Gynecology and Obstetrics, University Hospital, Palacký University, Olomouc.

METHODS

137 patients with fertility problems were included to the study. There were divided into two groups, patients with infertility and patients with repeated pregnancy loss. Screening test for celiac disease, serum level of antibodies tissue transglutaminase (tTGA) were performed in all of them. Positive test was confirmed by serological level of anti endomysium antibodies (EmA) and final diagnosis of silent celiac disease was done by enterobiopsy.

RESULTS

Celiac disease was found in two infertile patients (1.67%). In one patient the silent form was diagnosed by enterobiopsy. The second disease was latent form. In patients with repeated pregnancy loss we did not observe positive screening test.

CONCLUSION

We confirmed higher incidence of celiac disease in women with impaired fertility.