Collyriclosis in Red-backed Shrikes Lanius Collurio from Israel and Czech Republic.

One juvenile Red-backed shrike (Lanius collurio) with a cutaneous cyst of Collyriclum faba under its beak was observed in Israel on 13 October 2016. Another Red-backed shrike (adult female) with multiple cutaneous cysts around the vent was observed in Pruhonice, Czech Republic on 19 June 2017. A third Red-backed shrike (adult male) with three cutaneous cysts around the vent was observed in Mariánské Radcice, Czech Republic on 16 July 2017. In the Israeli case, two adult trematodes C. faba were found in the cutaneous cyst. In the two Czech cases, C. faba was identified indirectly by analysing the cutaneous cyst morphology. C. faba had never been recorded previously in Israel.

Electric Field Cancellation on Quartz by Rb Adsorbate-Induced Negative Electron Affinity.

We investigate the (0001) surface of single crystal quartz with a submonolayer of Rb adsorbates. Using Rydberg atom electromagnetically induced transparency, we investigate the electric fields resulting from Rb adsorbed on the quartz surface, and measure the activation energy of the Rb adsorbates. We show that the adsorbed Rb induces negative electron affinity (NEA) on the quartz surface. The NEA surface allows low energy electrons to bind to the surface and cancel the electric field from the Rb adsorbates. Our results will be important for integrating Rydberg atoms into hybrid quantum systems, as fundamental probes of atom-surface interactions, and for studies of 2D electron gases bound to surfaces.

Small-scale patterns in snowmelt timing affect gene flow and the distribution of genetic diversity in the alpine dwarf shrub Salix herbacea.

Current threats to biodiversity, such as climate change, are thought to alter the within-species genetic diversity among microhabitats in highly heterogeneous alpine environments. Assessing the spatial organization and dynamics of genetic diversity within species can help to predict the responses of organisms to environmental change. In this study, we evaluated whether small-scale heterogeneity in snowmelt timing restricts gene flow between microhabitats in the common long-lived dwarf shrub Salix herbacea L. We surveyed 273 genets across 12 early- and late-snowmelt sites (that is, ridges and snowbeds) in the Swiss Alps for phenological variation over 2 years and for genetic variation using seven SSR markers. Phenological differentiation triggered by differences in snowmelt timing did not correlate with genetic differentiation between microhabitats. On the contrary, extensive gene flow appeared to occur between microhabitats and slightly less extensively among adjacent mountains. However, ridges exhibited significantly lower levels of genetic diversity than snowbeds, and patterns of effective population size (Ne) and migration (Nem) between microhabitats were strongly asymmetric, with ridges acting as sources and snowbeds as sinks. As no recent genetic bottlenecks were detected in the studied sites, this asymmetry is likely to reflect current meta-population dynamics of the species dominated by gene flow via seeds rather than ancient re-colonization after the last glacial period. Overall, our results suggest that seed dispersal prevents snowmelt-driven genetic isolation, and snowbeds act as sinks of genetic diversity. We discuss the consequences of such small-scale variation in gene flow and diversity levels for population responses to climate change.

Increased spring freezing vulnerability for alpine shrubs under early snowmelt.

Alpine dwarf shrub communities are phenologically linked with snowmelt timing, so early spring exposure may increase risk of freezing damage during early development, and consequently reduce seasonal growth. We examined whether environmental factors (duration of snow cover, elevation) influenced size and the vulnerability of shrubs to spring freezing along elevational gradients and snow microhabitats by modelling the past frequency of spring freezing events. We sampled biomass and measured the size of Salix herbacea, Vaccinium myrtillus, Vaccinium uliginosum and Loiseleuria procumbens in late spring. Leaves were exposed to freezing temperatures to determine the temperature at which 50% of specimens are killed for each species and sampling site. By linking site snowmelt and temperatures to long-term climate measurements, we extrapolated the frequency of spring freezing events at each elevation, snow microhabitat and per species over 37 years. Snowmelt timing was significantly driven by microhabitat effects, but was independent of elevation. Shrub growth was neither enhanced nor reduced by earlier snowmelt, but decreased with elevation. Freezing resistance was strongly species dependent, and did not differ along the elevation or snowmelt gradient. Microclimate extrapolation suggested that potentially lethal freezing events (in May and June) occurred for three of the four species examined. Freezing events never occurred on late snow beds, and increased in frequency with earlier snowmelt and higher elevation. Extrapolated freezing events showed a slight, non-significant increase over the 37-year record. We suggest that earlier snowmelt does not enhance growth in four dominant alpine shrubs, but increases the risk of lethal spring freezing exposure for less freezing-resistant species.

Atom-based vector microwave electrometry using rubidium Rydberg atoms in a vapor cell.

It is clearly important to pursue atomic standards for quantities like electromagnetic fields, time, length, and gravity. We have recently shown using Rydberg states that Rb atoms in a vapor cell can serve as a practical, compact standard for microwave electric field strength. Here we demonstrate for the first time that Rb atoms excited in a vapor cell can also be used for vector microwave electrometry by using Rydberg-atom electromagnetically induced transparency. We describe the measurements necessary to obtain an arbitrary microwave electric field polarization at a resolution of 0.5°. We compare the experiments to theory and find them to be in excellent agreement.

[Laparoscopic pyeloplasty in adults--mid-term results in 32 laparoscopic pyeloplasties during 2003-2008]. / Laparoskopická pyeloplastika u dospelých--strednedobé výsledky 32 laparoskopických pyeloplastik 2003-2008.

Pyeloureteric iunction obstruction is the most common inborn error of the upper urinary pathways. In the time of routine prenatal ultrasound examination, this disease is discovered in the child's age, when it is treated most frequently. Publication summarizes the results of modern laparoscopic management in the adults, who had not been diagnosed previously and symptoms occurred many years after their birthdate. The surgical treatment has been changed in the approach, but not the goal of desobtruction. The results in the adults are influenced not only by the operation technique, but also by the length of time the obstruction lasted and by the number and severity of the inflammatory changes.

[Microsurgical subinguinal varicocelectomy in children and adolescents]. / Mikrochirurgická subingvinální varikokélektomie u detí a dospívajících.

BACKGROUND: Microsurgical varicocele repair has become the gold standard in adults and only a few reports are available in children and adolescents. We present our experience with this method and concentrate on the technical performance, complications and development of testicular size. METHODS AND RESULTS: 47 patients aged 11 to 18 years (x15.4) underwent microsurgical subinguinal repair for varicocele grade II.-III. Operation was indicated because of hypoplastic testicle (expressed by the atrophy index > 25%), pain, large varicocele or parents preference. The patients were examined clinically, by ultrasound including the Doppler study; hormonal examination was added using the gonadoreline stimulation test. Microscope has been used to identify the internal spermatic artery, to dissect the artery from the complex of small surrounding veins and to identify the lymphatic vessels. We found 3 recurrences in 46 patients (6%) operated for primary varicocele. The atrophy index decreased from x19.7 to 12.7%, without any association with pubertal stage. Atrophy of the testis was not found in any patient. Hydrocele was detected in one patient (2.1%), and left testicular hypertrophy also in one patient (2.1%). CONCLUSIONS: Microsurgical subinguinal varicocelectomy is a safe and efficacious method in children and adolescents; using the microscopic dissection, the internal spermatic artery and accompanying lymphatic vessels are safely spared.

[Endoscopic and conservative treatment of vesicoureteric reflux]. / Endoskopická a konzervativní lécba vezikoureterálního refluxu.

BACKGROUND: The aim of study is to evaluate the results of endoscopic treatment of vesicoureteric reflux (VUR) comparing with conservative mode. METHODS AND RESULTS: In the years 2003-2006 there were forty for children in prospective randomised study enrolled and divided into two groups. Twenty two children 1-40 months old (22.9 months) were operated. Dx/Ha (Deflux) was instilled for VUR grade 3-5. The results of treatment were compared with outcome of twenty two conservatively treated randomly assigned children aged 1-32 months (mean age 13.5 months) Postoperative videourodynamic study was used to evaluate for the presence of VUR and function of the bladder and ultrasound investigation was performed too (exclusion of obstructive megaureter in operated group). There were 22 children controled after instillation. The children were followed 11-24 months. VUR was cured in 12 cases (54.5%) and improved (grade 1-2) in 5 children (66.7%). All children absolved treatment without any complications, excluding one case with obstructive megaureter after pyelonephritis diagnosed. There were 22 children evaluated in conservative group. Five children were cured (22.7%) and VUR was improved (grade 1-2) in four (18.2%) CONCLUSIONS: Endoscopic miniinvasive instillation of dextranomer is safe and effective treatment of VUR in all age groups with good therapeutical outcome and minimum of adverse effects.

[Progress of laparoscopic surgery in adults at the Department of Urology of the First Faculty of Medicine and General Teaching Hospital]. / Rozvoj laparoskopické operativy dospelých na Urologické klinice 1. LF UK a VFN v Praze.

Laparoscopy is the most modern operative technique, the main advantage of which is the least invasivity. In urology, the laparoscopy has won its yield only in nineties of 20th century, but it was in urology, where the robots were launched as first, and nowadays using them it is possible to perform ablative/reconstructive surgery in a tiny intracorporeal space. The price of laparoscopic operations is high and has been the only limit up to now, but technical approaches and indications have already been fixed.

[Analysis of results of percutaneous nephrolithotomies]. / Analýza výsledku perkutánních extrakcí konkrementu.

BACKGROUND: Percutaneous nephrolithotomy is an effective less invasive method for the treatment of nephrolithiasis. Authors retrospectively analysed results of this procedure performed in a single centre (Department of Urology, General University Hospital, Prague) from January 2005 till June 2007. METHODS AND RESULTS: Patients were acquired by an analysis of operating reports performed over a period January 2005 till June 2007 and subsequently a retrospective analysis of electronic and paper patient's records was carried out. Percutaneous nephrolithotomy was performed in 150 patients. Of those, 117 (78%) patients underwent primary and 33 (21.3%) secondary procedure. Analysed group consisted of 85 (56.7%) men and 65 (43.3%) women. Right-sided procedure was performed in 46% (69 times) and left-sided in 54% (81 times) of cases. Mean patient's age was 52.9 years (SD +/- 16.3). Mean stone size was 18.3 (SD +/- 9.5) mm. Staghorn calculi were present in 19 (12.7%) patients and 77 (51.3%) patients had more than 1 stone. Intracorporeal lithotripsy was necessary in 82 (54.7%) cases. Seventy eight (52.9%) patients were stone free after the procedure. There were 24 (16%) patients with an anatomic abnormality of upper urinary tract. The most common (in 64.3%) component in analysed stones was a calcium oxalate. CONCLUSIONS: The amount of stone free patients is rather lower compared to the literature results. However, definitive results are always affected by auxiliary procedures (mainly extracorporeal shock wave lithotripsy), which are not included in the analysis.

Structural basis of HIV-1 and HIV-2 protease inhibition by a monoclonal antibody.

BACKGROUND: Since the demonstration that the protease of the human immunodeficiency virus (HIV Pr) is essential in the viral life cycle, this enzyme has become one of the primary targets for antiviral drug design. The murine monoclonal antibody 1696 (mAb1696), produced by immunization with the HIV-1 protease, inhibits the catalytic activity of the enzyme of both the HIV-1 and HIV-2 isolates with inhibition constants in the low nanomolar range. The antibody cross-reacts with peptides that include the N terminus of the enzyme, a region that is highly conserved in sequence among different viral strains and that, furthermore, is crucial for homodimerization to the active enzymatic form. RESULTS: We report here the crystal structure at 2.7 A resolution of a recombinant single-chain Fv fragment of mAb1696 as a complex with a cross-reactive peptide of the HIV-1 protease. The antibody-antigen interactions observed in this complex provide a structural basis for understanding the origin of the broad reactivity of mAb-1696 for the HIV-1 and HIV-2 proteases and their respective N-terminal peptides. CONCLUSION: A possible mechanism of HIV-protease inhibition by mAb1696 is proposed that could help the design of inhibitors aimed at binding inactive monomeric species.

The role of aminoacyl-tRNA binding site on the factor EF-T in uncoupled GTPase reaction.

The properties of the N-tosyl-L-phenylalanyl chloromethane treated EF-T factor were studied in a ribosomal system in which splitting of GTP occurs. The action of N-tosyl-L-phenylalanyl chloromethane inhibits the binding of aminoacyl-tRNA to the EF-T factor. The binding and exchange of guanosine phosphates continued to be preserved. The inhibited factor is inactive in the GTPase reaction which depends on the participation of ribosomes and aminoacyl-tRNA. The uncoupled GTPase reaction (which is not dependent on the presence of aminoacyl-tRNA) is also sensitive to the effect of the inhibitor. The inhibition of the uncoupled GTPase is incomplete. These findings are attributed to the involvement of the aminoacyl-tRNA binding site of the EF-T factor in the uncoupled GTPase reaction.

Three-dimensional structure of an Fab-peptide complex: structural basis of HIV-1 protease inhibition by a monoclonal antibody.

F11.2.32, a monoclonal antibody raised against HIV-1 protease (Kd = 5 nM), which inhibits proteolytic activity of the enzyme (K(inh) = 35(+/-3)nM), has been studied by crystallographic methods. The three-dimensional structure of the complex between the Fab fragment and a synthetic peptide, spanning residues 36 to 46 of the protease, has been determined at 2.2 A resolution, and that of the Fab in the free state has been determined at 2.6 A resolution. The refined model of the complex reveals ten well-ordered residues of the peptide (P36 to P45) bound in a hydrophobic cavity at the centre of the antigen-binding site. The peptide adopts a beta hairpin-like structure in which residues P38 to P42 form a type II beta-turn conformation. An intermolecular antiparallel beta-sheet is formed between the peptide and the CDR3-H loop of the antibody; additional polar interactions occur between main-chain atoms of the peptide and hydroxyl groups from tyrosine residues protruding from CDR1-L and CDR3-H. Three water molecules, located at the antigen-antibody interface, mediate polar interactions between the peptide and the most buried hypervariable loops, CDR3-L and CDR1-H. A comparison between the free and complexed Fab fragments shows that significant conformational changes occur in the long hypervariable regions, CDR1-L and CDR3-H, upon binding the peptide. The conformation of the bound peptide, which shows no overall structural similarity to the corresponding segment in HIV-1 protease, suggests that F11.2.32 might inhibit proteolysis by distorting the native structure of the enzyme.

[Comprehensive long-term analysis of hypospadias repair using vascularized flaps and tubularized incized plates--report on 588 cases]. / Dlouhodobé výsledky rekonstrukce hypospadie pomocí vaskularizovaných laloku a tubulizace incidované ploténky--588 prípadu.

BACKGROUND: The article presents a comprehensive long-term analysis of the modem hypospadias repair based on preservation and use of the urethral plate. METHODS AND RESULTS: In years 1987 to 2004, 476 patients (aged 8 months to 45 years) were operated using a praeputial (mostly) flap. 81% were indicated for reconstruction of a proximal form of hypospadias, mostly penile. In years 1986 to 1991, a tubularized flap was performed in 31 patients. Since 1992, an onlay island flap in 394 patients, inlay-onlay flap in 43 patients and onlay-tube-onlay flap in 8 patients have been used. In years 2000 to 2004, 112 patients (aged 13 months do 17 years) were operated using tubularized incised plate (TIP) repair, mostly because of distal form of hypospadias. To cover the neourethra, a dartos flap was used in 72 and spongioplasty in 37 patients. We achieved the primary healing in 89% and 91%, resp., of patients after onlay and onlay-inlay island flap repairs with an average follow-up of 6,7 and 5,7 years, respectively. The most frequent complications were fistula or dehiscence of the glans. After the TIP repair combined with a dartos flap, 89% of the first operated patients healed without complications with an average follow-up of 2.3 years. A higher complication rate (40%) was found after a spongioplasty with foreskin preservation. Secondary repairs were also associated with more complications. CONCLUSIONS: Using onlay and inlay-onlay one-stage repairs, or using TIP one-stage repair combined with a dartos flap, a successful primary hypospadias repair was achieved in 90% of patients. The definite repair should be completed during early childhood.

[Effect of biofeedback in the treatment of voiding dysfunction]. / Efekt biofeedbacku v lécbe nonneurogenních dysfunkcí dolních mocových cest u detí.

BACKGROUND: Biofeedback represents a treatment option for children with voiding dysfunction characterised with poor pelvic floor relaxation. METHODS AND RESULTS: Thirty nine children with symptoms of voiding dysfunction were treated in BFB program. Average number of sessions to achieve good response was three. Follow up was 12 to 24 months. Very good clinical response was obtained in 55, 7% of patients, who were characterised by cessation or resolution of incontinence in 66, 7%, dyscoordination in 57, 6% and urinary tract infection in 41, 1% of children. CONCLUSIONS: Biofeedback therapy is an effective method for treating poor pelvic floor relaxation. It helps to improve coordination of the detrusor and external sphincter function and it accelerates voiding reflex maturation.

Bronchial arteries in experimental pulmonary infarction: angiographic and morphometric study.

OBJECTIVES: The aim was to investigate (1) whether collateral bronchopulmonary circulation developing due to chronic pulmonary embolism could prevent the evolution of pulmonary infarction after induction of pulmonary venous outflow impairment; and (2) how collateral bronchopulmonary circulation developed after acute embolisation of the lung with impaired pulmonary venous outflow. METHODS: Fifty two mongrel dogs were studied. Thirty six dogs were experimental animals and 16 were in a control group. Unilateral impairment of pulmonary venous outflow was induced by constriction of the left pulmonary veins in two groups of experimental dogs: (1) three months after and (2) one hour before bilateral embolisation of the pulmonary artery. All animals were killed 12 days after constriction. The size of the bronchial arteries was evaluated from angiograms. The diameter and the wall thickness of the arteries were measured during histology. RESULTS: In all experimental dogs, haemorrhagic infarctions developed distally to emboli in the left lung regardless of whether the bronchial arteries were dilated before induction of pulmonary venous constriction or whether collateral circulation started to develop after pulmonary venous constriction. Constriction of the pulmonary veins was an essential factor for pulmonary infarction to develop as no infarction developed in the embolised regions of the right lungs with intact pulmonary venous outflow. Pulmonary venous constriction alone did not cause dilatation or hypertrophy of the bronchial arteries. After pulmonary artery embolisation, the same enlargement and hypertrophy of the bronchial arteries occurred both in the left lung with previously impaired venous outflow and in the right lung with intact pulmonary veins. CONCLUSIONS: Expanded bronchopulmonary circulation did not prevent the development of infarction in the embolised region of the lung with impaired pulmonary venous outflow. Development of collateral bronchopulmonary circulation was not influenced by previously impaired pulmonary venous outflow.

Preliminary crystallographic studies of an anti-HIV-1 protease antibody that inhibits enzyme activity.

F11.2.32, a monoclonal antibody directed against the HIV-1 protease, displays strong inhibitory effects toward the catalytic activity of the enzyme. The antibody cross-reacts with peptides 36-46 and 36-57 from the protease. Crystals of the Fab have been obtained both in the free state and as complexes formed with the protease peptide fragments, 36-46 and 36-57. Diffraction data have been collected for the free and complexed forms of Fab F11.2.32 and preliminary models for the crystal structures were obtained by molecular replacement.

Inhibition of the HIV-1 and HIV-2 proteases by a monoclonal antibody.

The monoclonal antibody 1696, directed against the HIV-1 protease, displays strong inhibitory effects toward the catalytic activity of the enzyme of both the HIV-1 and HIV-2 isolates. This antibody cross-reacts with peptides that include the N-terminus of the enzyme, a region that is well conserved in sequence among different viral strains and which, furthermore, is crucial for homodimerization to the active enzymatic form. This observation, as well as antigen-binding studies in the presence of an active site inhibitor, suggest that 1696 inhibits the HIV protease by destabilizing its active homodimeric form. To characterize further how the antibody 1696 inhibits the HIV-1 and HIV-2 proteases, we have solved the crystal structure of its Fab fragment by molecular replacement and refined it at 3.0 A resolution. The antigen binding site has a deep cavity at its center, which is lined mainly by acidic and hydrophobic residues, and is large enough to accommodate several antigen residues. The structure of the Fab 1696 could form a starting basis for the design of alternative HIV protease-inhibiting molecules of broad specificity.

Expression and properties of prochymosin derivatives containing extensions of various length in the pro-part.

A series of hybrid prochymosin derivatives containing portions of the simian virus 40 small-t antigen in the pro-part was constructed. Portions comprising 93, 63, 47, 12, and 1 amino acid (aa) from the N terminus of the small-t antigen were separately fused via eight polylinker-encoded amino acids to a prochymosin product commencing with the 5th aa of the pro-part. All the DNAs coding for the hybrid proteins were put under pL-promoter control in the expression constructs. Expression revealed that only fusion of the 47-aa or 12-aa stretch of the small-t antigen to prochymosin gave stable protein products and that only the latter one allowed the hybrid prochymosin to be activated to chymosin. The products containing 93 aa and 63 aa of small-t antigen were unstable and degraded. Complete removal of the small-t antigen portion led to mRNA instability, probably owing to inefficient initiation of translation.

Processed enzymatically active protease (p15gag) of avian retrovirus obtained in an E. coli system expressing a recombinant precursor (Pr25lac-delta gag).

Processing proteases of avian and mammalian retroviruses cut the polyprotein precursors encoded by the retroviral genes into mature functional proteins. Retroviral processing proteases are still a rather poorly characterized group as to their relation to other proteases, specificity, and mechanism of enzymatic action. In avian retroviruses the generation of the processing protease itself comprises a processing cleavage event - the protease p15gag is cut off the carboxy-terminus of a gag polyprotein precursor, Pr76gag. We report here that direct and efficient production of the avian retrovirus processing protease p15gag (required for structure-function studies and rational design of inhibitors) was obtained in an E. coli system, where massive expression of a size-reduced, recombinant precursor (Pr25lac-delta gag) was accompanied by its structurally accurate processing.