Image contrast in high-resolution electron microscopy of biological macromolecules: TMV in ice.

It is shown that the contrast in high-resolution electron micrographs of biological macromolecules, illustrated by a study of TMV in ice, falls considerably below the level which should theoretically be attained. The factors which contribute to the low contrast include radiation damage, inelastic scattering, specimen movement and charging. Future progress depends on improved understanding of their contributions and relative importance. Contrast is defined as the amplitude of a particular Fourier component extracted from an image in comparison to that expected by extrapolation from separate electron or X-ray diffraction measurements. The fall in contrast gets worse with increased resolution and is particularly serious at 10 A and beyond for specimens embedded in vitreous ice, a method of specimen preparation which is otherwise particularly desirable because of the expectation that the embedded molecules should be well preserved in a near-native environment. This low contrast at high resolution is the principal limitation to atomic-resolution structure determination by electron microscopy. In spite of good progress in the direction of better images, it remains a major problem which prevents electron microscopy from becoming a simple and rapid method for biological atomic structure determination.


[Analysis of DNA polymorphism of cluster genes in cattle: casein genes and major histocompatibility complex (MHC) genes].

The PCR-analysis method has been used to study polymorphism of casein genes (k- and b-caseins) and genes of class of basic histocompatibility complex (DRB and DQB BoLA) in some cattle breeds. Genotyping of k-casein locus has been carried out using analysis of protein polymorphism and DNA polymorphism. It is shown that both methods give identical results and can be used for this purpose, but the PCR-analysis method is more informative. A new allele of k-casein gene (k-Cn F) has been revealed and sequenced using the above method. While analyzing DNA-polymorphism of 5'-nontranslated region of b-casein gene two previously non-described polymorphic sites for restrictase Hinf I are found which occur only in animals of "zebu-like" breed. The high level of polymorphism of bl-domain of gene DRB is shown: polymorphism of bl-domain was revealed already at the level of electrophoretic analysis of PCR-amplification products. For 5'-nontranslated domain gene DQB the polymorphism level was much lower and manifested itself during restriction analysis of amplified fragments.


[Analysis of the results of genotype assessment in Black Pied bulls and ways of improving their breeding value].

The results from the genetic-population analysis of the testing of the black-white breed bulls used in reproduction centers located in Ukrainian Polesje are presented. The methods of the compositions of the parent pairs with the aim to obtain the advantageous animals are analysed.


[Heritability and ways of selection of pedigreed bulls according to reproductive capacity].

Significant heritability (to 0.92) by sperm output data from 248 simmental stud bulls has been determined using correlation and dispersion methods. The additive component of heritability is not significant. Application of the best bulls is most effective for selection on sperm productivity.


Electron cryomicroscopy of frozen-hydrated biological specimens: analysis of freezing artifacts by X-ray cryocrystallography.

Freezing artifacts have been evaluated by X-ray cryocrystallography on pellets of two-dimensional membrane protein crystals: purple membrane and maltoporin. The comparison of the X-ray patterns recorded when the specimens are maintained at room temperature to those obtained when the specimens are maintained at about -160 degrees C shows that (i) membrane proteins have a positive thermal dilatation coefficient: the protein crystal lattice shrinks upon cooling; (ii) the asymmetric unit of crystal containing water is changed upon freezing; the relative intensities of the diffraction rings of such crystals are different after freezing. From these results, it can be postulated that freezing may lead to partial dehydration of biological objects. Electron cryomicroscopy visualizes objects which are structurally influenced by the cooling procedure. However, our microscopy study on maltoporin crystals shows that freezing artifacts are negligible in comparison to artifacts associated with conventional techniques such as negative staining.


[Genetic structure of the Orlov trotter and the Russian trotter].

The genetic structures of Orlov's and Russian trotters for 16 biochemical systems have been comparatively analyzed. Polymorphism of 6 systems of these horse groups is revealed. The main genetic differentiation between Orlov's and Russian trotters is observed on the transferrin and phosphoglucomutase loci.


[Hematologic chimerism in cattle twins].

A cytogenetic examination of a cow and its offsprings, obtained by pair transplantations of the embryos was carried out. The fragile X and the heteromorphism of the chromosomes XX of this cow and some of its offsprings were revealed. The variability of the hematological chimerism of the pair transplanted embryos was observed. The immigrated cells were, as a rule, distinguished by the comparatively low frequencies of the metaphases with the nearly located chromosomes XX. The heterogeneity of the stem blood cells of the embryos for some traits, and for the ability to migrate in the blood of the twin is under discussion.


Automatic focus correction for spot-scan imaging of tilted specimens.

The variation in defocus within an image of a highly tilted specimen can be a serious source of artifact. Spot-scan imaging can be combined with dynamic focusing to greatly reduce this range of defocus. A protocol is described for determining the parameters required for the automatic focus compensation during the recording of a spot-scan image. Images of a gold test specimen demonstrate the efficacy of this procedure in extending the area of the image that contains high-quality data. In case the tilt angle or resolution is high enough that the height difference of the specimen within each small illuminated area is larger than the depth of field, the image must be treated to compensate for the focus variation. The same principle is used as was developed for compensation of conventional images of tilted specimens.


[Interdependence between milk productivity of cattle and a complex of loci of a coupled block of caseins and beta-lactoglobulin].

The complex lactoprotein markers, connected with the different level of milking capacity and fat percentage are found in cattle on the basis of experimental data. The high correlation is stated between selection of beta-lactoglobulin alleles and alleles of the coupled gene casein blocks on the levels of microevolution herds and macroevolution breeds.


Automated microscopy for electron tomography.

Instrumentation and methodology for the automatic collection of tomographic tilt series data for the three-dimensional reconstruction of single particles is described. The system consists of a Philips EM 430 TEM, with a Gatan 673 cooled slow-scan CCD camera and a Philips C400 microscope computer control unit attached. The procedure for data collection includes direct digital recording of the images on the CCD camera and the automatic measurement and correction of (a) image shifts resulting from tilting the specimen, (b) variation of defocus and (c) the eucentric height position of the specimen. Experiments are described illustrating the possibilities and limitations of automatic data collection. Data collection at a magnification of 30k shows that the exposure time of the specimen to the beam is reduced by a factor of 10-100 compared to manual operation of the TEM.


Computer-controlled spot-scan imaging of crotoxin complex crystals with 400 keV electrons at near-atomic resolution.

400 keV electrons yield a better relative image contrast than 100 keV electrons for a beam-sensitive organic crystal when spot-scan imaging is used [J. Brink and W. Chiu, J. Microscopy 161 (1991) 279]. A FORTRAN 77 program has been written to operate the spot-scan imaging system on a computer workstation under the VMS operating system which is interfaced serially to the JEOL4000 electron microscope. We demonstrate the application of this implementation by imaging crotoxin complex crystals embedded in either vitreous ice or glucose to 2.5 A resolution. The intensity strength of the structure factors of this protein crystal are different at low (> 10 A) resolution but similar at high resolution (< 10 A) for the two embedding media as expected from their scattering contrast difference. Based on our experience as judged from the electron diffraction patterns of highly tilted crystals, flat crystals embedded in glucose can be readily obtained. Furthermore, our spot-scan imaging system also has the option of correcting the focus gradient that is present in images of tilted specimens.


Processing images of helical structures: a new twist.

Helical macromolecular assemblies are particularly difficult to study by X-ray diffraction but are quite well suited to analysis by electron microscopy. Most of our information about helical macromolecular assemblies has come from the electron microscope but has been limited to about 25 A resolution. With the use of low-dose electron cryomicroscopy, one can obtain structural data to near atomic resolution on two-dimensional crystals, but the problem is to extract the information from the noise. In this paper we present methods to extract signal from low-dose electron cryomicrographs of helically symmetric structures. We apply these methods to extract 10 A data from the bacterial flagellar filament.


Specimen flatness of thin crystalline arrays: influence of the substrate.

The extreme degree of specimen flatness (i.e. planarity) required for high-resolution electron diffraction and electron microscopy at high tilt angles cannot be realized with thin, sheet-like crystals of biological macromolecules, just on the basis of the intrinsic stiffness of the specimen itself. In an effort to improve the rate of success at which suitably flat specimens are prepared, this paper analyzes several different factors that can either limit or enhance the specimen flatness. If specimens are adsorbed (by attractive forces) to a support film, such as evaporated carbon, which itself is not flat to atomic dimensions, quantitative calculations show that it is quite likely that the specimen will be too wrinkled to be used for high-resolution studies. Adsorption to an air-water interface is more likely to result in the necessary degree of flatness. Repulsive interactions, which might be used to "sandwich" a specimen between two interfaces, are estimated to be too "soft", i.e. too long-range in character, to be effective. Finally, if only one edge of a specimen sticks firmly to a substrate, then surface tension forces can pull the specimen taut over the surface of the substrate, so that the specimen itself can be more flat than the surface of the substrate upon which it is deposited. A second, important consideration in many studies is the fact that cooling the specimen to low temperature can result in specimen wrinkling, because of the fact that the biological crystal has a much larger coefficient of thermal expansion than that of the evaporated carbon film. In this case one expects that cooling-induced wrinkling might be reduced by using a metal support grid which has a smaller thermal coefficient than that of the carbon film. The validity of this qualitative idea is supported by experiments which show that cooling-induced wrinkling of glucose-embedded purple membrane can be prevented if molybdenum grids are used rather than copper.


2D crystallization: from art to science.

The techniques as well as the principles of the 2D crystallization of membrane and water-soluble proteins for electron crystallography are reviewed. First, the biophysics of the interactions between proteins, lipids and detergents is surveyed. Second, crystallization of membrane proteins in situ and by reconstitution methods is discussed, and the various factors involved are addressed. Third, we elaborate on the 2D crystallization of water-soluble proteins, both in solution and at interfaces, such as lipid monolayers, mica, carbon film or mercury surfaces. Finally, techniques and instrumentations that are required for 2D crystallization are described.


Has negative staining still a place in biomacromolecular electron microscopy?

Transmission electron microscopy of proteins has provided molecular- and in a few cases near-atomic-resolution structural information. In this review, we critically evaluate the potential and the limitations in obtaining molecular resolution, particularly with negatively stained specimens, and put these into perspective with cryomicroscopy of unstained frozen-hydrated and sugar-embedded preparations.


Assessment of resolution in biological electron crystallography.

The resolution of images or density maps produced by electron microscopy and electron crystallography can be objectively defined in terms of the spatial frequency of the highest resolution diffraction spot, or Fourier coefficient, included in the data processing. In practice, this objective definition of resolution is expected to be too optimistic if the amplitudes of the highest resolution structure factors are too weak, if the population of high resolution reflections is too sparse, or if the signal-to-noise ratio of the high resolution data is too low. Calculated examples are presented here which illustrate how the apparent resolution in images of a membrane protein, bacteriorhodopsin, can be reduced from a nominal value of 3.5 A by weak amplitudes, sparse data or high noise levels. These calculations provide concrete examples which can serve as a guide when estimating whether the objective definition of image resolution is likely to correspond to a practical, structurally useful estimate of image resolution.


Emission microscopy and related techniques: resolution in photoelectron microscopy, low energy electron microscopy and mirror electron microscopy.

A unified treatment of the resolution of three closely related techniques is presented: emission electron microscopy (particularly photoelectron microscopy, PEM), low energy electron microscopy (LEEM), and mirror electron microscopy (MEM). The resolution calculation is based on the intensity distribution in the image plane for an object of finite size rather than for a point source. The calculations take into account the spherical and chromatic aberrations of the accelerating field and of the objective lens. Intensity distributions for a range of energies in the electron beam are obtained by adding the single-energy distributions weighted according to the energy distribution function. The diffraction error is taken into account separately. A working resolution is calculated that includes the practical requirement for a finite exposure time, and hence a finite non-zero current in the image. The expressions for the aberration coefficients are the same in PEM and LEEM. The calculated aberrations in MEM are somewhat smaller than for PEM and LEEM. The resolution of PEM is calculated to be about 50 A, assuming conventional UV excitation sources, which provide current densities at the specimen of 5 x 10(-5) A/cm2 and emission energies ranging up to 0.5 eV. A resolution of about 70 A has been demonstrated experimentally. The emission current density at the specimen is higher in LEEM and MEM because an electron gun is used in place of a UV source. For a current density of 5 x 10(-4) A/cm2 and the same electron optical parameters as for PEM, the resolution is calculated to be 27 A for LEEM and 21 A for MEM.


High-resolution scanning electron microscopy.

The spatial resolution of the scanning electron microscope is limited by at least three factors: the diameter of the electron probe, the size and shape of the beam/specimen interaction volume with the solid for the mode of imaging employed and the Poisson statistics of the detected signal. Any practical consideration of the high-resolution performance of the SEM must therefore also involve a knowledge of the contrast available from the signal producing the image and the radiation sensitivity of the specimen. With state-of-the-art electron optics, resolutions of the order of 1 nm are now possible. The optimum conditions for achieving such performance with the minimum radiation damage to the specimen correspond to beam energies in the range 1-3 keV. Progress beyond this level may be restricted by the delocalization of SE production and ultimate limits to electron-optical performance.


Architectural distortion of subcutaneous fascial layer in breast tumors: ultrasonographic evaluation.

To develop a criterion to evaluate architectural changes of the subcutaneous tissue layer around the breast, 120 patients with histologically proven tumors were studied as to ultrasonographical delineation of the superficial layer (SL) of the superficial fascia. Breast ultrasonography was performed using an electronic-linear scanner with a 5.0 MHz probe. When SL was identified over the tumor, it was classified into 3 types: flat, disrupted, and convergent types. SL was identified in 106 patients (88%). Forty-six were evaluated to be flat type, and 41 (89%) of them had benign tumors. The remaining 60 were subdivided into either disrupted (n = 44) or convergent type (n = 16); 53 (88%) of these 60 cases had cancerous lesions. Histologically, inward retraction of SL was the most common pattern in breast cancer. Thus, the ultrasonographic pattern of SL reflects the histological findings and can be a useful clue to differentiate benign lesions from cancerous ones.


Modulation of middle cerebral artery flow velocity waveforms by breathing movements in the normal term fetus.

Breathing dependency of fetal middle cerebral artery flow velocities was studied in 10 normal pregnancies at term. Peak systolic, end-diastolic and time-averaged flow velocities and pulsatility index during fetal breathing were not significantly different from those observed during apnoea. However, the standard deviation for each flow velocity parameter was significantly increased during fetal breathing activity, indicating marked modulation of middle cerebral artery velocities.


Reproducibility of fetal cardiac flow velocity waveforms at atrioventricular level.

Reproducibility of flow velocity waveform recording and analysis was studied at fetal atrioventricular level (mitral and tricuspid valve) in 25 normal pregnancies. The flow velocity parameters studied were peak-E wave velocity, peak-A wave velocity and time-averaged velocity. In each patient, two consecutive measurements were performed (time delay, 15 min) and of each measurement two hardcopies were analyzed. A high reproducibility was achieved for all parameters studied; the coefficients of variation between readings of hardcopies were < or = 2% and the coefficients of variation between tests within patients were < or = 4%.


Digital path-dependent recompensation of contrast-enhanced echocardiographic images.

The regional video intensity of two-dimensional (2D) ultrasonographic images is directly affected by energy losses from the ultrasonic beam propagating between the transducer and the specific region of interest (ROI). These losses are mainly dependent on the scattering and absorption properties of the more proximal tissues. The commonly utilized automatic time-gain compensation (TGC) procedures, based on the assumption of uniform scattering and energy conversion throughout the investigated tissues and organs, seem to be largely inadequate in the contrast echocardiographic studies which attempt to quantitate the contrast enhancement of myocardial tissue. We hereby present an algorithm for the non-linear adaptive path-dependent recompensation of the ultrasonographic video intensity for the non-uniform scattering and absorption in images obtained using automatic TGC. The variable energy losses are estimated in our technique according to the reflections from the different points along the acoustic beam. The proposed algorithm is a post-processing function. It was developed considering beam attenuation by scattering and absorption and comparing correction procedures necessary with and without the assumption of uniform attenuation. We hereby present the results obtained by applying this algorithm to contrast enhanced echocardiographic images of canine hearts. The artifacts produced by the inadequate automatic TGC are essentially reduced by the recompensation procedure. The recompensation allows the observation of the changes in video intensity induced in the myocardial tissue by contrast-enhancing media, which are otherwise severely obscured by contrast transit altering the propagation effects.


Use of ultrasound to detect intestinal wall ischemia in piglets.

To evaluate the use of ultrasound (US) to detect intestinal wall ischemia, we isolated segments of jejunum on single vascular pedicles in five piglets. We sequentially clamped these segments in intervals of 0 to 6 h, reperfused them for 24 h, and then examined them in vitro histologically and with an 8.5 MHz US scan. All segments were grossly viable except those with 6 h of ischemia. Histologically, mild submucosal edema developed after 1 to 2 h of ischemia; after 3 to 4 h, mucosal necrosis, loss of folds, worsening submucosal edema, and prominent neutrophilic infiltration occurred; after 5 to 6 h, severe mucosal necrosis with hemorrhage and submucosal edema was present. Ultrasonically, we saw five wall layers in the control group corresponding to mucosa, submucosa, muscularis propria, and subserosal fat. After mild (1 to 2 h) ischemia, all layers were present except for a discontinuity in layer 3. After moderate (3 to 4 h) ischemia, the five layers persisted but with a markedly thickened submucosal layer, reduced echogenicity, and flattened mucosal folds. With severe (5 to 6 h) ischemia, we observed a loss of all normal layers with no discernible architecture. Using these US criteria, blinded observers were able to differentiate normal/mild from moderate/severe ischemia with a sensitivity and specificity of 100%. These data suggest that US can differentiate, in vitro, normal from moderate and severe degrees of intestinal wall ischemia that correlates well with the histological appearance. Endoscopic US or surgically implantable US probes can potentially help diagnose clinical intestinal wall ischemia.


The effect of heparin versus citrate on blood echogenicity in vitro: the role of platelet and platelet-neutrophil aggregates.

There is no consensus among investigators regarding which anticoagulant to use when studying the causes of in vitro blood echogenicity, despite the fact that heparin and calcium-chelating anticoagulants may have disparate effects due to their differing effects on platelets. This study quantitated the echogenicity of heparinized blood compared to citrated blood and found that it was greater in heparinized blood than in citrated blood when paired samples from the same donor, drawn at the same time were compared. By microscopic examination of the blood, this difference appeared to be due to the formation of platelet and platelet-neutrophil aggregates in the heparinized blood. This hypothesis was tested by comparing the echogenicity of heparinized blood to that of heparinized blood following platelet and white cell depletion. The results showed that taking away platelets and white cells virtually eliminated the echogenicity of heparinized blood; the impact of this result is discussed in the context of in vivo spontaneous contrast.


A method for computer simulation of ultrasound Doppler color flow images--I. Theory and numerical method.

Ultrasound imaging systems utilizing the pulsed Doppler principle are capable of providing images of blood flow in real time. We present a useful method for simulating flow images on a computer. Our method assumes that blood and surrounding tissue consist of many point-like scatters positioned randomly in three dimensions. The position-dependent acoustic response of each scatterer is calculated using the acoustic impulse response method. This method takes into account the spatial effects of the transducer geometry on both the amplitude and temporal response of point-scattering. Details of theory, assumptions made in the simulation, and numerical methods are described fully for a spherically focused transducer, as well as a discussion of signal processing for generation of the flow image. Motion of a single scatterer is investigated to test the performance of the simulation algorithm. This simulation method could potentially be beneficial for detailed study of current and future flow imaging systems.


A method for computer simulation of ultrasound Doppler color flow images--II. Simulation results.

A computational method of simulating Doppler color flow images has been developed. It is based on a point-scattering model of moving blood and surrounding tissue and is capable of treating the entire flow image generation process. Simulated images of parabolic flow dynamics in a cylindrical vessel are presented to show the statistical nature of the map of velocity estimates and to demonstrate the effects of wall filters and different display schemes. Quantitative results of extracted velocity profiles are included and indicate the usefulness of the simulation method for studying the quantitative capabilities of flow imaging.


New method of estimating the ultrasonic beam ratio parameter for characterizing sound propagation in tissue.

The backscattered ultrasonic signal from soft tissue can be considered to consist of two parts: a spatially fluctuating component due to coherent scattering from randomly distributed scattering centers and a relatively constant component related to structural ordering. The relationship between these, which has been termed the "beam ratio parameter" influences the speckle pattern of an ultrasound image. First-order image statistics for this special speckle pattern are characterized by the Rician distribution. Changes of second-order statistics have also been derived as a function of the beam ratio parameter. A new method for the estimation of the beam ratio parameter from the intensity distribution of the ultrasonic signal is described in this paper. This method was used to measure the parameter in ultrasonic images from phantoms and liver tissue yielding values of about 0.1. The measured changes of the second-order statistics were not correlated to this parameter. The results indicate that the relatively constant intensity component related to structural ordering has only a small influence on the speckle pattern.


[Imaging of acute abdomen. Contribution of new radiological methods and practices].

The acute abdomen is a sudden clinicoradiologic problem that may be resolved promptly by an excellent collaboration between the referring physician and the radiologist. The advent of CT and US has modified the diagnostical approach of acute abdomen. As diagnosis should be assessed in the shortest time with the greatest care and accuracy, it is necessary to choose the appropriate available examinations, reducing the time needed to establish a diagnosis and decreasing the number of examinations required. Thus, this paper is geared toward the determination and the choice of the more accurate procedure for the clinical presentation of acute abdominal emergencies.


Neural tube defects--prenatal diagnosis and management.

Neural tube defects rank second to congenital heart disease as a major cause of congenital malformation. Recent developments in ultrasound have improved prenatal diagnosis. Due to anomaly scans at 18 weeks gestation and the availability of a genetic clinic, prenatal diagnosis of neural tube defects at the Royal Maternity Hospital was 91.2% during 1987-1989. However, only 50% of parents accept termination of pregnancy and it is questionable if prenatal diagnosis is of benefit to those who wish to continue with the pregnancy. Parents may accept the situation better at birth, having had time to come to terms with it, helped with support from the obstetrician, clinical geneticist, paediatrician, genetic nurse and social worker. For some affected fetuses who have better muscle function and leg movement at term it appears from the literature that the outcome may be improved by caesarean section delivery. In Ireland fetuses with neural tube defects will continue to be delivered, as termination is unacceptable to many, but despite this there may be a positive benefit from prenatal diagnosis of neural tube defects. Prospective randomised controlled trials are needed to confirm benefit from delivery by caesarean section for fetuses with a good prognosis. As a result of prenatal diagnosis of a neural tube lesion the fetus should enjoy benefit in terms of physical morbidity, and the parents should benefit in terms of psychological morbidity.


[Policies regarding non-resuscitation and cessation of treatment in Quebec hospitals].

This paper presents the results of a survey addressed between 1987 and 1989 to the directors of professional services of all Quebec hospitals. The objective was to record and analyse withholding and withdrawal of treatment policies, and in particular DNR orders. The paper summarizes the analysis of the principles and ethical values involved in existing policies. It therefore considers descriptive ethics rather than normative ethics, and does not discuss ethical issues in themselves.


Coeliac disease: clinical presentations, correlations of dietary compliance, symptomatic response and repeat biopsy findings.

Gastrointestinal symptoms were present at the time of diagnosis in 81 (76%) of 107 patients with coeliac disease: 56% had diarrhoea/steatorrhoea, 32.7% abdominal pain and 15% constipation. Gastrointestinal symptoms were commonest in young adults (20-39 years) and less frequent in children (0-19 years). Anaemia, low serum levels of folic acid, albumin and calcium, and raised serum alkaline phosphatase may be of help in raising the index of diagnostic suspicion, but in over half of our patients with clinically and histologically active disease these values were within normal limits. In patients adhering to a gluten free diet remission of symptoms correlated well with histological response; the continuation of symptoms indicated a higher incidence of histological abnormality. No patient not complying to the diet had normal histology on repeat biopsy. Five patients died over the ten year period, one from a small bowel lymphoma.


What do medical students know about chronic pain and its management?

A questionnaire on chronic pain management was completed by 114 third year, and 80 fifth (final) year medical students. The results demonstrated a significant improvement in most facets of chronic pain knowledge and management by the end of the medical course. A postal survey was undertaken of all pain clinics in Northern Ireland to identify current activity, as these figures are not collected in Korner returns. Despite the improvement in knowledge by final year, there were still many students who did not know what type of problem to refer to a pain clinic (30%), who ran the clinics (> 40%), or the types of treatment commonly employed. More formal education is required on this subject, at both undergraduate and postgraduate level.


The Belfast hip screener: from infancy to maturity.

Hip dislocation remains the most significant childhood orthopaedic abnormality despite the efforts of neonatal screening, first described in 1910. A new method of enhancing the performance of screening, the Belfast hip screener, is a non-invasive device developed to detect and interpret the vibrations ("clicks" and "clunks") which are emitted as the hips are physically tested. A progress report is presented covering ten years' work from early records made with tape recorders to modern methods of digital signal processing.


Benefits of an exercise class for elderly women following hip surgery.

A prospective cohort study of a twice weekly exercise programme for six months was undertaken to determine the benefits of an exercise class for 28 elderly women following hip surgery. The effects of the exercise programme were monitored using cycle ergometry. Walking speed was measured on entry and at 3, 6 and 12 months. Twenty-six subjects completed the programme with an overall attendance rate of 88%. Measures of fitness, calculated from cycle ergometry, did not improve significantly apart from test duration. In contrast there was a significant improvement in mean walking speed, with a 50% increase between 0 and 3 months and a further 21% increase between 3 and 6 months. This improvement was maintained at 12 months.


Five cases of Alcaligenes pseudobacteraemia.

A cluster of five cases of pseudobacteraemia due to the organism Alcaligenes denitrificans occurred in three hospital medical wards over a four week period. The same organism was isolated from four of twelve commercially prepared bottles for erythrocyte sedimentation tests. The most likely explanation for the outbreak is that the ESR bottles were filled prior to inoculation of blood culture bottles. The outbreak was brought to an end by advising on correct procedure.


Continuing medical education for general practitioners--a Northern Ireland plan.

Following the introduction of the 1990 contract for general practitioners and the new postgraduate education allowance, the Northern Ireland Continuing Medical Education Group, comprising the clinical tutors from four Belfast hospitals and members of the University department of general practice, was established to provide high quality co-ordinated continuing medical education for general practitioners. A questionnaire was sent to all general practitioners in Northern Ireland to find out their needs and preferences with regard to continuing education. The responses indicate the value of small group discussion as well as the traditional lecture and the important role of local hospital consultants in providing education. Therapeutics, recent advances in medicine and learning new skills are all desirable topics. The group intends to use this information in the provision of courses for general practitioners in the province.


[Our experience with the complex treatment of phlegmon of the lacrimal sac].

Eighty-nine patients with lacrimal sac phlegmons, 76 women and 13 men, aged 16 to 78, were administered multiple-modality treatment, consisting in Group 1 (43 patients) of traditional methods, such as UHF therapy, antibiotics, sulfonamides, symptomatic therapy, dacryocystorhinostomy after complete cessation of inflammation, and in group 2 (46 patients) including sessions of intermittent magnetic field (IMF) exposure, antibiotics, and early dacryocystorhinostomy. Sparing technique was used in all operations, carried out under local anesthesia with 2% procaine or trimecaine. IMF exposure was found to be an effective therapeutic means characterized by antiinflammatory, resolving, and analgesic effects. IMF sessions and early dacryocystorhinostomy enhance cessation of inflammation and improve the treatment efficacy: remote results of surgery were excellent in 80% of Group 1 patients and in 90.9% of Group 2 patients; As a results of IMF exposure, the terms of medical and social rehabilitation of patients with the lacrimal sac phlegmons were reduced twofold.


[Histological characteristics of ocular structures after YAG-laser exposure of various sections of the crystalline lens in experimental studies].

This work was aimed at analysis of all the aspects, pathomorphologic included, of short-pulsed YAG laser exposure of the lens. Experiments were carried out with 79 rabbit eyes. After laser exposure the eyes were enucleated in 1-24 h and in 7-10 days. Thirty-one eyes were subjected to YAG laser ++capsule puncture. Fragmentation of intracapsular structures was carried out in 23 eyes. Combined operations were performed on 25 eyes. Every series comprised two groups, differing by the energy of laser exposure: 3-5 mJ. Histologic analysis has lead the authors to the following conclusions. The pattern and severity of pathomorphologic changes were directly related to the energy and time of laser exposure and site of the focal plane of irradiation. The major destructive shifts after YAG laser fragmentation of the cortical layer and capsulotomy are focussed at the site of exposure and involve the adjacent sections of the lens. Laser exposure of 3-5 mJ may be used to open the anterior capsule of the lens and to facilitate the cataract mass discharge in extracapsular cataract extraction. Use of combined method helps enhance induration and fragmentation of the cortical layers of the lens, rules out surgical discission of the anterior capsule of the lens, and facilitates removal of the nucleus and wash out of the lens mass.


[Technique and results of modified trabeculectomy].

The author suggests double trabeculectomy with episclera resection and anguloplasty to be performed in cases with uncompensated open-angle glaucoma. Each of the elements of such surgery is aimed at slowing down the reparative processes in various sections of the fistulous route and therefore this route can function longer. Forty-six patients (50 eyes) with primary open-angle glaucoma were operated on. Normalization of the ophthalmic tone immediately after surgery was achieved in 100% of cases. The results of surgery were followed up in 30 patients (32 eyes) for 6 months to 2 years. Stable normalization of intraocular pressure was achieved in 97% of cases, vision acuity in 81%, and visual field in 91% of those operated on. Good stable hypotensive effect of such surgery recommends it most of all for patients at a high risk of excessive cicatrization (young patients, repeated surgery, etc.).


[Possible causes of rise of the intraocular pressure after trabeculectomy and the ways of their correction].

Basing on the results of follow-up of 50 patients repeatedly operated on at the site of previous trabeculectomy, the authors recommend to stick to a certain order of surgical manipulations and stop the intervention when intraocular pressure is reduced to its normal level on the operative table. Such technique, together with the use of a viscous sponge to prevent coarse postoperative adhesions, helped achieve a stable hypotensive effect that was present for at least 2 years in the overwhelming majority of the patients operated on repeatedly.


[Results of the clinical study of a new adrenergic beta blocker levobunolol hydrochloride in healthy subjects and in patients with glaucoma].

Effects of a single instillation of levobunolol, a new nonselective beta-adrenoblocker, in normal subjects and patients with various forms of glaucoma were under study, as were the effects of prolonged administration of this drug in patients with open-angle glaucoma. Short-term observations have revealed a hypotensive effect in all the examinees, the highest in patients with open-angle glaucoma (30.2%). Levobunolol did not influence the diameter of the pupil and accommodation, nor did it essentially change the cardiovascular activity. Prolonged administration of the drug resulted in a stable reduction of intraocular pressure by 20-30% in 70% of patients with open-angle glaucoma. Tonographic studies have shown that the drug reduced the intraocular fluid production and in case of a prolonged administration a trend to an elevation of the coefficient of the easiness of fluid discharge is observed.


[A surgical method for the treatment of traumatic low-solubility hyphema].

Presents experimental and clinical data on the operation of 'angular drainage' of the anterior chamber in traumatic poorly soluble hyphemas. The operation consists in conduction of a supramide thread through performed orifices in the cornea and formation of an angular drainage for blood evacuation from the anterior chamber. High efficacy and safety of the suggested method for treatment of recurrent complicated hyphemas is proved.


[Prospects of using fluorescein angiography with oral administration of fluorescein in children].

Search for the subjective methods for the diagnosis of diseases of the fundus oculi in children necessitates the development of new methods. The authors are investigating the possibility of fluorescent angiography with oral administration of fluorescein with due consideration for the allergologic history and other conditions that may be contraindications against intravenous administration of the agent to children. Fluorescent angiography was carried out in 15 children aged 4 to 15. The procedure was well tolerated, no complications were recorded.


[Coagulative and fibrinolytic activities of the lacrimal fluid in health and in acute disorders of blood circulation in the eyes].

Three effective methods, differing by their labor and time consumption, for the assessment of the lacrimal fluid fibrinolytic and coagulation activities are suggested. These methods were tried in examinations of 79 patients with acute disorders of ocular circulation. The results evidence that lacrimal fluid examinations are more informative than analysis of the blood collected from the ulnar vein.


[Differential diagnosis of retinoblastoma and Coats' retinitis using computer-assisted processing of ultrasonographic scanograms of the eye].

A new method for quantitative evaluation of ultrasonic scanograms of the eye, that permits differentiation between retinoblastoma and Coats' retinitis, was employed in echographic examinations of the eyes in 21 children with suspected intraocular volumic processes. Image analysis by plotting and processing of histogram was employed. High-confidence differences in the 'excess' and 'skewness' meanings of gradient histograms of patients with these two conditions have been detected.


[Immunodiagnosis of retinoblastoma].

To improve the accuracy of early diagnosis of retinoblastoma, the authors have examined a number of cellular and humoral immunity parameters in 188 children with retinoblastomas, in 57 ones with nontumorous conditions of the eyes, and in healthy controls. Stages III-IV retinoblastoma was found associated with reduced blood levels of IgG and IgA and a still more marked reduction of both in the lacrimal fluid (4-fold), with reduced blood T lymphocyte count (by 1.5 times), decreased lymphocyte blastogenesis response to phytohemagglutinin (by 8-9 times), reduced leukocyte migration activity (MI = 79 +/- 10%), reduced serum thymic activity (by 2.5 times). The early (I-II) stage of the disease involves a lowering of only lacrimal fluid IgA (2-fold) and of the leukocyte migration index (MI) (89 +/- 2%). This index was found to be an important specific indicator for the early preoperative diagnosis of retinoblastoma. Leukocyte migration inhibition (MI less than 95%) by retinoblastoma antigens was observed only if this tumor was present. In cases with the nontumorous conditions and in health retinoblastoma antigens as a rule stimulated the leukocyte migration (MI over 95%).


[Causes of anaphylactoid reactions in cattle after administration of lipoid preparations].

In 1986-1988, adverse anaphylactoid reactions (AR) were observed in animals in Czechoslovakia after the administration of oil adjuvant-containing vaccines or other lipoid drugs. Treated animals showed signs resembling the classic anaphylactic reaction, i.e. restlessness, salivation, pruritus, oedema and cyanosis of udder and vulva, and eyelid oedema, developing within a few minutes. The reactions were not elicited by the antigen alone, but by the oil adjuvant. The aim of our experiments was to identify substances eliciting the reaction in susceptible animals and to investigate possible induction mechanisms. The emulsifier Tween 80 has been demonstrated to be an AR inducing component of vaccines and drugs (Tab. I and III). Weak or moderate reactions were observed in 33% of animals treated with 5% Tween and 66% of those treated with 10% Tween showed strong reactions. On the other hand, no reactions were elicited by treatment with several paraffin oils of different quality (Tab. I) nor with an oil-in-water emulsion containing Montanid as an emulsifier (Tab. II). The role of the vegetative nervous system in the rise of AR has been confirmed. AR were suppressed in animals pretreated with parasympatholytic atropine and enhanced in a part of those pretreated with parasympathomimetic pilocarpine (Tab. III). The percentage of animals affected and the intensity of AR were also lower in animals pretreated with complement inhibitor epsilon-aminocapronic acid (Tab. IV). A major role of complement activation is suggested in the discussion of possible mechanisms of AR induction. It is possible to draw a conclusion on the basis of the results presented here and of the analysis of individual cases that a certain degree of animal susceptibility, depending on the phase of reproductive cycle, metabolism level and neurovegetative balance is necessary besides the administration of an AR inducer (Tween 80 in our case). Hence it seems that the adverse anaphylactoid reactions results from interactions of the two factors, i.e. administration of an AR inducer to susceptible animals.


[Use of parasitic wasps (Hymenoptera: Pteromalidae) in the biological control of domestic flies in pig housing].

Adaptability of two parasitoid species S. nigroaenea and M. zaraptor to conditions of stable microclimate was investigated in a farrowing house. The colony was reared in an insectary at a temperature of 24-26 degrees C and relative humidity of 60-70% in cages of the size 0.3 x 0.3 x 0.2 m. The development of the species M. zaraptor from egg to adult lasted 19 to 23 days, in S. nigroaenea it was 23 to 25 days. Rates of parasitism of house fly pupae were followed in plastic pots (8 x 4 x 9 cm) with larval medium for fly rearing. The larval medium consisted of milk powder, wheat bran and dried yeast. Both species were demonstrated to be able to penetrate to pupae in deeper layers of the medium (Tab. 1) and in this way to control the amounts of fly adults after their eclosion. The results were evaluated by Student's t-test. 98% of flies in the stable were house flies (Musca domestica L.), the remaining flies were stable flies (Stomoxys calcitrans L.). No parasitoids were observed in the stable. Two pots containing 2-3,000 pupae parasitized by S. nigroaenea and M. zaraptor were placed in the stable on 30th January 1990. Parasitoids were monitored at three locations of the stable according to parasitism rates of lab-reared house fly pupae exposed in plastic pots with larval medium. Twenty-two checks were made in 2 to 4 week intervals from February to November 1990, and one final check after a six-month interruption (Tab. II). Both species persisted in the stable for the whole period of observation (Fig. 1). The species S. nigroaenea, the population levels of which were much higher, showed the greater migration activity after its individuals had been released to the stable. Sprayings with the Alfacron insecticide were performed in the stable in March and September 1990 in the course of this experiment.


[Ecotoxicologic relations on a large pig-fattening farm located in a lignite mining area and near and solid-fuel electical power plant].

Major contaminants identified in 1983-1984 on a pig fattening farm with an output of 60,000 pigs per annum, located in a lignite mining area and near a solid fuel power plant, were mercury, cadmium, lead, chromium and aflatoxin B1 (Tab. I, II, III, IV). Feed samples were collected from througs to assess the contamination load at feed uptake. Permissible concentrations of mercury, chromium, cadmium, aflatoxin B1, lead and atrazin in the feed were exceeded in 56, 50, 31, 19, 6 and 6% samples, respectively (Tab. I). Stable dust deposits, in which the contaminants concentrate, (Tab. I) proved to be a suitable material for assessing the type and level of environmental contamination. Permissible concentrations of mercury, cadmium and lead in porcine muscles were exceeded in 65, 51 and 24% samples, respectively (Tab. III). Corresponding values of mercury, cadmium, lead and aflatoxin B1 in the liver were 27, 27, 16 and 3%, respectively (Tab. III) and those of mercury, lead and chromium in kidneys 24, 22 and 5%, respectively (Tab. III). Rather surprisingly, elevated pancreatic concentrations of aflatoxin B1 were found (Tab. IV). Pigs fattened in the contaminated environment (i.e. fed contaminated feed mixtures, inspiring contaminated dust and absorbing percutaneously contaminants form dust deposits on the body surface) showed: 1) Impairment of the genetic apparatus (percentage of aberrant peripheral leucocytes elevated to 6.2%); 2) a certain degree of immunosuppression (concentrations of IgG, IgM and IgA reduced by 16.9, 45.1 and 45.0%, respectively); 3) higher feed consumption per 1 kg weight gain (4 kg) and lower average daily weight gain (0.57 kg); 4) increased incidence of health disorders (dermatitis in 25%, pancreatopathy in 13%, liver dystrophy in 8% and femoral fracture in 6% of the pigs). Unfortunately, the authors were not allowed to analyse ash and solid emissions from the power plant. Therefore the share of the emissions in the overall environmental contamination on the fattening farm could not be quantified. The personnel, working in the contaminated environment for a prolonged period, is endangered most of all by stable dust, being exposed to its mechanical, chemical, allergic and infectious effects (Tab. I). In addition to the chemical contaminants, 21 mould genera and species, six mite species and numerous saprophytic and some pathogenic bacteria were demonstrated in stable dust samples in our earlier experiments. Consumption of meat and organs from pigs fattened in a contaminated environment is associated with the risk of an increased uptake of various contaminants.(ABSTRACT TRUNCATED AT 400 WORDS)


[Dynamics of changes in the cytological picture of vaginal smears and circulating ovarian hormones during the puerperal period in ewes].

A postparturient period is characterized by low basal secretion of adenohypophysis gonadotropins with the following appropriate changes in ovarian hormones and their response to the morphology of vaginal epithelium. In this study the dynamics of the cytological picture of vaginal swabs and ovarian hormones 17 beta-oestradiol (E2) and progesterone was investigated in the puerpery of ewes. The objective was to obtain and extend the knowledge of cytological changes in vaginal epithelium and levels of ovarian hormones of ewes after parturition and of their relationships from the first several days after lambing until the 51st day of the period of observation. Vaginal swabs for vaginal cytology were taken from nine ewes on days 1, 4, 7, 14, 17, 21, 25, 34, 42 and 51 after parturition. These swabs were fixed in ether-alcohol 1:1, stained according to the Faltínová-Zidovský method, embedded in Canada balsam and evaluated by differentiation of cells according to Luksh (1953). Blood samples for E2 and P4 determinations were taken from the jugular vein in the same intervals as vaginal swabs. The serum was centrifuged and stored at -18 degrees C until use. E2 and P4 concentrations were determined radioimmunologically, using kits RIA-test ESTRA and RIA-test PROG from URVJT Kosice. A statistically significant decline (P < 0.05) of percentual representation of basal and parabasal cells (Fig. 1, Tab. I) on day 7 after lambing was replaced by their multiplication from day 14 reaching the values of 66.07 +/- 3.95 on day 42. A statistically significant decrease in intermediary flat cells (Fig. 2, Tab. II) was observed on days 14 (P < 0.001), 34 and 42 (P < 0.01; P < 0.001), in comparison with the first day after lambing. An evaluation of intermediary convoluted cells revealed their highest percentage on days 1 and 17 after parturition (34.65 +/- 4.77-20.62 +/- 12.57) and their decline to values in the range of 6.77 +/- 1.46-7.66 +/- 2.25 on the remaining days of the period of observation. Percent occurrence of superficial flat cells (Fig. 3, Tab. I) ranged from 3.9 +/- 1.10 to 10.63 +/- 7.23 from day 1 to day 51 after lambing. The lowest percentual representation (1.32 +/- 0.79-4.10 +/- 1.89) was recorded for superficial convoluted cells. Multiplication of the evaluated cells was observed, reaching the highest but insignificant representation (P > 0.05) on day 25 of postparturient investigation: 4.10 +/- 1.89 (Fig. 3, Tab. I). 17 beta-oestradiol (E2) concentrations were compared to the -1st day before parturition, when its values varied at the level of 2.45 +/- 0.64 nmol/l serum.(ABSTRACT TRUNCATED AT 400 WORDS)


[Use of polychlorinated biphenyl congener analysis for monitoring food and raw material of animal origin].

Occurrence of individual polychlorinated biphenyl (PCB) congeners in the environment, foodstuffs and other biological materials was assessed. Analysis of specific PCB congeners (28, 52, 101, 138, 153, 180), occurring in animal raw materials and foodstuffs most frequently, has been implemented. Sample processing, isolation of fat from milk, meat, organs, fat tissue and eggs, and separation of PCB from fats using the sorbents Florisil or Ekosorb (a new Czechoslovak sorbent based on modified silica gel, Kavalier Glassworks, Votice) are described in detail. Individual PCB congeners were determined by capillary gas chromatography (gas chromatograph Varian VISTA 6,000, equipped with a 63Ni ECD; silica capillary column SPB-5, 30 m x 0.32 mm I.D., 0.25 micron film; column temperature programme: 60 degrees C for 2 min, then to 250 degrees C at 20 degrees C/min and held for 13 min; splitless injection). Chromatograms of commercial chemicals Delor 103 and Delor 106 (corresponding to Aroclor 1242 and 1260, respectively), of a mixture of six specific PCB congener standards and of a PCB--containing milk sample are presented in Fig. 1-3. Methods of PCBs estimation, currently used in Czechoslovakia, and benefits of congeneric analysis of PCBs (reproducibility of results, quantification of individual congeners) are discussed. Analysis of specific PCB congeners is used for the assay of PCBs in foodstuffs and investigations of PCBs dynamics in food chains and distribution and accumulation of PCBs in animal organisms. Contents of specific PCB congeners in milk, pork and pig liver and kidney samples are given in Tab. II.(ABSTRACT TRUNCATED AT 250 WORDS)


Chronic valvular disease in the cavalier King Charles spaniel in Sweden.

The prevalence of chronic valvular disease was studied in 494 cavalier King Charles spaniels with a mean (+/- sd) age of 3.0 +/- 2.7 years. Cardiac murmurs were detected in 65 (13.2 per cent) of the dogs. Among 61 cavalier King Charles spaniels with a mean age of 6.4 +/- 2.8 years, cardiac murmurs were detected in 32 (52 per cent). In both groups of dogs the prevalence of cardiac murmurs was low among dogs younger than three years (1.9 per cent) but increased with age (P < 0.001). The estimated ages at which 50 per cent of the dogs had developed murmurs were 7.5 and 6.2 years, respectively. When 39 of the 61 dogs were re-examined three years later, cardiac murmurs were detected in 28 (72 per cent), and the intensities of the murmurs had generally increased (P < 0.05). Nine (28 per cent) of the dogs which had previously had murmurs had been euthanased for signs of congestive heart failure whereas none of the dogs which had been free of murmurs had died from congestive heart failure. Animal insurance statistics from 1982 to 1990 (1983 excluded) for dogs less than 10 years old showed that claims for veterinary care or death or euthanasia were five times more common in the cavalier King Charles spaniel than in dachshunds (P < 0.001) and eight times more common than the mean for all other insured breeds (P < 0.001).


Occurrence of cataracts in triploid Atlantic salmon (Salmo salar) on four farms in Scotland.

In September 1991 cataracts occurred in two year-classes of triploid Atlantic salmon. The fish showed varying degrees of blindness, were lethargic and became emaciated owing to their inability to feed. The lesions in the lens were mainly in the anterior and posterior cortex and perinuclear areas, the capsule and embryonic nucleus remaining unaffected. Diploid fish of the same year-class did not have cataracts. The origin of the triploid fish, the method of triploidisation, their diet and disease status were investigated, but no predisposing factors could be found to account for the high incidence of cataracts.


[Use of cytostatics as anti-cicatricial drugs after anti-glaucoma surgery in children, adolescents and young adults].

Anti-cicatricial cytostatic therapy with 5-fluorouracil and prospidin was carried out after antiglaucoma surgery in 78 eyes of 67 patients aged 6 to 42 (2/3 of the patients were aged from 21 to 40). Half (34) of the patients suffered from open-angle (pigmented in 3 cases) and 6 from closed-angle glaucoma, the rest patients presented with common hydrophthalmia, the Frank-Kamenetsky, Sturdge-Weber, Riger's syndromes, etc. The cytostatics were injected subconjunctivally. The results of 67 surgeries were followed up for 6 months to 3 years. Stable normalization of the ophthalmic tone and stabilization of the process were achieved in 60 eyes (89.2%). The authors emphasize that cytostatics may be recommended for children and young subjects after surgery involving fistulization, on condition of thorough biomicroscopic monitoring in the postoperative period, because of a possible disadaptation of the edges of the mucosal incision and corneal diseases.


A double-blind comparison of olive oil and a combination of evening primrose oil and fish oil in the management of canine atopy.

A randomised double-blind parallel study lasting eight weeks was used to assess the effects of olive oil in a group of atopic dogs whose clinical signs were well controlled by dietary supplementation with a combination of evening primrose oil and fish oil. Nine of the 11 dogs which continued to receive this combination were considered unchanged at the conclusion of the study, whereas eight of the 10 dogs switched to olive oil had deteriorated. The mean plasma concentration of dihomogammalinolenic acid, a precursor of potentially antiinflammatory mediators, was significantly reduced (P < 0.05) in the olive oil-treated group at the end of the study. There were no significant differences between the mean plasma linoleic, eicosapentaenoic and arachidonic acid concentrations in the two groups. These findings suggest that olive oil is not an effective therapeutic agent in the control of canine atopy.


Real-time ultrasonography for determining the gestational age of ewes.

Seven Swedish peltsheep ewes were examined weekly by transabdominal ultrasound scanning from one-and-a-half to two months of gestation until parturition. By means of a simple regression analysis, the heart rate, the biparietal diameter of the skull and the diameter of the body trunk were correlated with fetal age, and it was concluded that these measurements could be used to estimate the age of the fetus.


[Laser correction of recurrence of increased intraocular pressure after surgical valvular sinuso-trabeculectomy].

Wise's laser trabeculoplasty with a 270 degrees exposure was used in 22 eyes of 22 patients with operated-on decompensated glaucoma. Patients with elevated decompensated intraocular pressure after sinusotrabeculoctomy were included in this group. The postoperative fistula was located in front of the Schlemm's canal in them. A dynamic follow-up has shown a stable normalization of the ophthalmic tone in 62% of cases without maintenance therapy. As a repeated intervention, laser trabeculoplasty is less traumatic, yields a good therapeutic effect, and may be widely used as a method to correct elevated intraocular pressure after earlier sinusotrabeculectomy.


[A method of tracing Schlemm's canal in the combined treatment of open-angle glaucoma].

Tracing Schlemm's canal in the course of sinusotomy, added to multiple-modality treatment of open-angle glaucoma, helps improve the localization of the site of initially traced external wall of Schlemm's canal in gonioscopy and carry out laser trabeculopuncture at the site of the intervention with a lower level of laser energy, as well as reduce the possibility of complications and cicatrix of the trabecula and the adjacent tissues. A follow-up of 23 patients over 1.5 years has proved that the described intervention provides a good hypotensive effect and stabilization of the glaucomatous process in the overwhelming majority of patients.


Approaches to the identification of non-essential genes of African swine fever virus.

It is poorly understood why vaccines could not be developed for the control and prevention of African swine fever (ASF) virus infection. The aim of our study was to identify genes non-essential for ASF virus replication because there were indications that certain viral gene products, which apparently are non-essential for viral replication, conferred protection from death due to ASF. A cosmid library representing the genome of ASF virus strain France 64 was established and characterized. Then, in order to inactivate viral genes by insertion, the beta-galactosidase (beta-gal) gene was introduced either randomly or at specific locations of selected cloned DNA fragments. These constructions were transfected into cells which had been previously infected with a cell-culture-adapted viral strain in order to allow the generation of recombinant progeny virus. Viable recombinant progeny was identified by at least one of the following means: (1) expression of beta-gal; (2) detection of beta-gal specific DNA by plaque hybridization, and (3) absence of a functional product of the inactivated gene. Presently, we are characterizing a recombinant virus with an insertionally inactivated thymidine kinase gene.


African horse sickness in Spain.

The aetiology, pathogenesis and epizootiology of African horse sickness (AHS) are reviewed with special reference to recent outbreaks in the Iberian peninsula. AHS is a highly fatal insect-borne viral disease of Equidae. It is caused by an Orbivirus (family Reoviridae) and nine serotypes are recognised. Outbreaks occurred in central Spain in 1987 and in southern regions of the Iberian peninsula in 1988, 1989 and 1990. All were associated with serotype 4 of the virus, whereas other occurrences of AHS outside Africa have all been caused by serotype 9. The clinical picture in the outbreaks was mainly of the acute (pulmonary) form except in 1988 when the subacute (cardiac) form of disease predominated. Several hundred horses died or were destroyed as a result of the outbreaks. Further spread was contained by a combination of slaughter of sick animals, movement controls, and vaccination which was extended over an increasingly wide area in successive years. The 1987 outbreak is believed to be associated with infected zebras imported from Africa. Possible explanations for the recurrence of disease in Spain in successive years are considered to include (a) the climatic conditions in Southern Spain, which could permit continuous vector activity, (b) the relative clinical resistance of mules and donkeys, which may permit subclinical circulation of the virus, (c) incomplete population immunity among horses due to possible gaps in the vaccination strategy.


Virus-induced acquired immune suppression by cytotoxic T cell-mediated immunopathology.

Acute infection with lymphocytic choriomeningitis virus causes a severe immune suppression in immunocompetent mice by triggering a T cell-mediated immunopathology, probably directed against infected macrophages and dendritic cells. An important role of gamma interferon may be to protect lymphohaemopoietic cells from virus infection and destruction by cytopathic effects of either the virus or of anti-viral immunity.


Diagnostic methods for African horsesickness virus using monoclonal antibodies to structural and non-structural proteins.

A panel of 32 hybridoma cell lines secreting monoclonal antibodies (MAbs) reactive with African horsesickness virus serotype 4 (AHSV-4) has been developed. Four of the MAbs recognized the major core antigen VP7, twenty recognized the outer capsid protein VP2 and eight reacted with the non-structural protein NS1. With the VP7-specific MAbs a rapid and sensitive double antibody sandwich immunoassay has been developed to detect viral antigen in infected Vero cells and in spleen tissue from AHSV-infected horses. The sensitivity of the assay is 10 ng viral antigen per 100 microliters. The NS1-specific MAbs allowed visualization by immunofluorescence of tubule-like structures in the cytoplasm of infected Vero cells. This can be very useful as a confirmatory diagnostic procedure. The antigenic map of the outer capsid VP2 protein with MAbs is also reported.


Lelystad virus, the cause of porcine epidemic abortion and respiratory syndrome: a review of mystery swine disease research at Lelystad.

This paper reviews the laboratory investigations that led us to isolate the Lelystad virus and demonstrate that this virus causes mystery swine disease. We describe: 1) isolating the virus from the disease; 2) characterizing the virus as a new enveloped RNA virus; 3) reproducing the disease experimentally with the isolated Lelystad virus; 4) isolating the virus from the experimentally induced disease.


Isolation of a Lelystad virus-like agent from British pigs and scanning electron microscopy of infected macrophages.

Six, one-week-old gnotobiotic piglets were inoculated with tissues or sera collected from field cases of porcine reproductive and respiratory syndrome. The piglets showed little or no illness, and two that were necropsied at 8 and 9 days post infection appeared grossly normal. However, a Lelystad virus-like agent was isolated from most of the inoculated pigs using porcine alveolar macrophage cultures. Seroconversion to the Lelystad virus was observed and some animals developed microscopically detectable interstitial pneumonias. Scanning electron microscopy was used to study the in vitro cytopathic effect of the Lelystad virus on porcine alveolar macrophages.


Immune mechanisms in the pathogenesis of viral diseases: a review.

Three immunopathological mechanisms may determine the pathogenesis of viral diseases in animals. (1) A variety of viruses causes transient or prolonged immunosuppression by infecting lymphoreticular tissues and interacting with components of the immune system. (2) In persistent viral infections effective immune responses may result in tissue damage. The mechanisms involved are T-cell-mediated destruction of infected cells and delayed-type hypersensitivity. (3) In a number of viral diseases pathogenic immune complexes are formed when antibodies are produced and react with viral antigen molecules persisting in the host. The selected examples of immune dysfunction are the focus of this review.


Porcine epidemic abortion and respiratory syndrome (mystery swine disease). Isolation in Spain of the causative agent and experimental reproduction of the disease.

In March of 1991, a disease that affected pregnant sows and caused a high mortality in unweaned piglets was detected in Spain. Based on the clinical signs observed, mystery swine disease, which had been described recently in Germany, Holland and Belgium, was suspected. From the samples obtained from the affected farm, a filtrable agent (0.22 micron) was isolated on cell culture. It produced cytopathic effects, its replication was intracytoplasmic, it was sensitive to chloroform, and cross-reacted with a Lelystad reference serum. When inoculated into pregnant sows, the agent produced inappetence for 2-4 days, without hyperthermia. One of the sows aborted at 100 days of gestation; the two others had delayed parturitions (days 115 and 116). There was a mixture of healthy piglets, mummified fetuses, stillbirths and weak piglets. Microscopic examination of the lungs of healthy piglets killed at 8 and 12 days of life revealed the presence of interstitial pneumonia. The sera from the three sows at 39 days after infection cross-reacted with the Lelystad virus (titres > or = 1/640), whereas pre-inoculation sera did not recognize it (titres < or = 1/10). This is the first report from Spain of the isolation of an agent (antigenically related to the Lelystad virus), capable of reproducing the disease previously designated as mystery swine disease.


The molecular biology of the porcine paramyxovirus LPMV.

Protein and genomic studies of a previously uncharacterized porcine paramyxovirus (designated LPMV) confirmed that it was a member of the paramyxovirus genus. The nucleotide sequences and deduced amino acids of the complete P-gene, M-gene, F-gene and HN-gene as well as the intergenic sequences have been determined. Comparative sequence analysis of the M-gene of LPMV revealed the closest relationship of LPMV was to human mumps virus with a homology of 46% and 55% at the amino acid and nucleotide levels respectively. The P-gene of LPMV is transcribed to V protein mRNA and by editing of the gene to the P protein mRNA. The LPMV P-gene has the coding capacity for an additional protein of 126 amino acids, a C protein.


Humanized animal viruses with special reference to the primate adaptation of morbillivirus.

This review article discusses the evolution of human viruses with special reference to paramyxoviruses. This family of viruses causes epidemics representing the dissemination of infection from one acutely infected host to the next. Since there is no repository for human paramyxoviruses in animals or in the form of persistent infections in man, the history of epidemics afflicting human civilization is short, presumably not exceeding 4000-5000 years. Evolutionary relationships can be deduced for comparison of nucleotide sequences of genes or even complete genomes. The present paramyxovirus genus will probably in the future be divided into two separate genera. In the genus morbillivirus, two pairs of more closely related virus types can be distinguished: canine and phocid viruses, and rinder-pest and measles viruses, respectively. It is speculated that recombination events may have occurred in the evolution of the morbillivirus archetype.


Round table on morbilliviruses in marine mammals.

Since 1988 morbilliviruses have been increasingly recognized and held responsible for mass mortality amongst harbour seals (Phoca vitulina) and other seal species. Virus isolations and characterization proved that morbilliviruses from seals in Northwest Europe were genetically distinct from other known members of this group including canine distemper virus (CDV), rinderpest virus, peste des petits ruminants virus and measles virus. An epidemic in Baikal seals in 1987 was apparently caused by a morbillivirus closely related to CDV so that two morbilliviruses have now been identified in two geographically distant seal populations, with only the group of isolates from Northwest Europe forming a new member of the genus morbillivirus: phocid distemper virus (PDV). Because of distemper-like disease, the Baikal seal morbillivirus was tentatively named PDV-2 in spite of its possible identity with CDV. The appearance of morbilliviruses in the Mediterranean Sea causing high mortality amongst dolphins should further increase the research activities on protection strategies for endangered species of marine mammals.


Round table on epidemiology and control of fox rabies.

The current epizootic of rabies in Europe has as its main host the fox. Oral vaccination of the fox population has proven to be particularly effective. It is clear that the major components for a successful vaccination programme are a potent and stable vaccine, and an effective baiting system; the latter should attract the target animal but no non-target species. Recently, vaccines of increased stability have been generated; amongst these is a vaccinia recombinant virus which expresses rabies virus glycoprotein. Consequently, both attenuated live virus vaccines and a recombinant vaccine are available for routine field vaccination of the fox population.


The pathogenic determinant of influenza virus.

Influenza viruses, like other viruses, must exhibit a genome constellation, which permits optimal virus reproduction in a given host. Besides this prerequisite the influenza virus haemagglutinin glycoprotein (HA) has been shown to be an essential determinant for pathogenicity. HA, which is synthesized as a precursor molecule, is activated by posttranslational cleavage by host proteases to obtain its full biological properties. Proteolytic activation is therefore indispensable for effective virus spread in the infected host and thus for pathogenicity. HA of the highly pathogenic avian influenza viruses inducing a systemic infection in birds is cleaved in a broad range of different host cells. On the other hand, HA of all mammalian viruses and the nonpathogenic avian strains, which cause local infection, exhibit a restricted cleavability. The prime determinant for these differences has been found to be the structure of the cleavage site. This concept was corroborated on virus mutants adapted in vitro to a new host.


Evidence for a viral aetiology of Jembrana disease in Bali cattle.

Jembrana disease is an acute infectious disease of Bali cattle (Bos javanicus) in Indonesia. High titres of the infectious agent are present in plasma during the febrile phase of the disease. The size of the agent determined by membrane filtration was between 50 and 100 nm, indicating it is a virus and not a rickettsia as previously proposed. Spherical virus-like particles of 75 to 130 nm diameter with a smooth membrane and frequently with an eccentric nucleoid were detected by electron microscopy in plasma from infected animals. The virus replicated in mononuclear cell cultures of peripheral blood origin but not in other cell cultures. The virus and the associated disease have characteristics consistent with viruses in the family Retroviridae.


The Zvonimir Dinter Memorial Lecture. New insights into the pathogenesis of viral infection.

Interesting recent highlights into the pathogenesis of viral infections have come from: (1) Studies of viruses that persist in cells and modify cell function without causing cell damage. (2) Transgenic mouse studies showing how tissue-specific transcriptional activators control virus expression and can determine viral tropism. (3) Studies of the influence of cell differentiation on viral expression. (4) The exploding world of cytokines, whose baffling complexity and multiple interactions are subjects of intense study. (5) Studies of the interaction of viruses with the immune system. In each case, no molecular studies are giving unprecedented insights into disease processes. However, even when viral genomes are sequenced and virulence genes identified there are additional daunting steps before we understand the role of a given gene product in pathogenesis.


[Asymptomatic HBs antigenemia in pregnant women].

The authors have dispensarized for more than ten years HBsAg carriers at the Second Medical Clinic of the Olomouc Faculty Hospital when antigenaemia was detected during blood donorship. Since 1990 the authors dispensarize also women where HBs antigenaemia was revealed during pregnancy. In the presented paper the authors analyze this group of women. In 1990-1991 the authors examined blood samples for HBsAg from 12,042 symptom-free pregnant women. HBsAg positivity was proved in 34 women (0.28%). Eleven women (32.3%) are regularly followed up since delivery. The authors know nothing about the fate of 10 women (29.4%), as they did not respond to repeated invitations to the surgery. It must be however mentioned that 6 of them are Vietnamese and probably left Czechoslovakia. Four women (11.7%) did not attend the clinic for examination but the authors know that they were delivered of their babies elsewhere. In the remainder, i.e. 8 women the delivery was normal, usually in term. The neonates were passively as well as actively immunized at the appropriate dates. Their umbilical blood (if collected) was HBsAg positive, while the venous blood was in all instances negative. All 20 women who attended examination were throughly examined (ultrasound, HBeAg, HBeAb etc.) and the clinical picture is that of a "healthy" HBsAg carrier (not verified by histological examination).


[Late ventricular potentials in patients with recurrent ventricular tachycardia after myocardial infarct].

In 26 patients who had at least two documented attacks of persisting ventricular tachycardia for 48 hours or longer after a myocardial infarction and whose standard QRS complex during sinus rhythm was < or = 120 ms, the authors examined late ventricular potentials using an Arrhythmia Research Technology apparatus EPX 1200. Positive finding were obtained in 19 (73%) of the patients. The finding is comparable with data in the literature on the prevalence of late ventricular potentials in patients with recurrent persisting ventricular tachycardia after myocardial infarction.


[Dual-cavity pacing for maximal work capacity in patients with a chronic high-grade atrioventricular block].

Twenty-eight patients with a grade 2 and 3 atrioventricular block and an implanted DDD pacemaker were repeatedly subjected to a bicycle ergometric test with a maximum load of the AV block (VV30), ventricular stimulation (VVI70) and DDD stimulation. The maximum work capacity and maximum heart rate achieved on VVI30 were 92 + xi 38 W and 61 +/- 27/min. The maximum work capacity increased on DDD by 49% while on VVI70 only by 22% (p < 0.00001) and the maximum heart rate increased on DDD by 185%, while on VVI70 only by 41% (p < 0.00001). The authors found a significant correlation between the increment of the maximum work capacity on DDD, as compared with that on VVI70 (d maximum work capacity) and maximum work capacity at VVI70 (r = -0.53, p < 0.01), maximum work capacity on VVI30 (r = -0.437, p > 0.03), maximum heart rate at VVI70 (r = -0.415, p < 0.004) and age (r = 0.56, p < 0.005). The d maximum work capacity was significantly higher in patients without their own ventricular activity during the load on VVI70 (28 +/- 24% vs. 13 +/- 8%, p < 0.05 (in patients who did not attain the upper frequency limit of DDD stimulation (30 +/- 25% vs. 14 +/- 9%, p < 0.004) and in patients above 60 years of age (37 +/- 26% vs. 14 +/- 10%, p < 0.002).


[Are dietetic and non-immunologic therapies becoming deciding factors in the treatment of autoimmune diseases?].

Authors call attention to non-immunological therapy and its determining role for fate and final prognosis in patients with autoimmune diseases. A stress importance of the timely and rigorous antihypertensive and antiinfectious treatment. From the dietary measures is best known favourable effect of the low protein diet and pharmacological limitation of the phosphorus supply. A new therapeutical aspect is the influence of the lipids on the autoimmune diseases activity and efficiency of the omega-3 unsaturated fatty acids. Non-immunological methods of the treatment are particularly valuable for the general practitioners and pediatricians, because enable them essentially to influence the course of the autoimmune diseases.


[On the 30th anniversary of the first hemodialysis in Slovakia].

The author reminds of the first attempts of therapeutic dialysis in Slovakia as well as the first instrumental haemodialysis implemented on August 15 1962 by doctors I. Ahlers, N. Scheid and T. Szabo in the Military Hospital in Kosice. Then he analyzes the development of dialyzation treatment in the Slovak Republic and compares the contemporary state with that in Europe.


[Prevalence of bone decalcification in the treatment of Crohn's disease].

In clinically active Crohn's disease the bone mineralization is impaired due to calcium malabsorption by the inflamed intestinal wall which is potentiated by diarrhoea and the thus accelerated transit time. To this we must add the shortening of the gut after operations, the inadequate dietary calcium supply or possibly calcium elimination in case of concurrent lactose intolerance. Corticoid treatment leads also to deterioration of bone mineralization. This is the reason why the authors assessed in 98 patients with Crohn's disease the bone mineralization, using the method of clavicular bone index (NIBA). Then treatment was started: a high protein diet, calcium forte, Ossin (sodium fluoride), vitamin D forte, anabolics and regular physical exercise. Check-up examinations after one year revealed that the index was restored in the majority of patients (60.84%) to normal. The above treatment is thus effective. It must be, however, regular and of a long-term character, in some patients it must extend over many years. We had, however, also patients who although subjected to an extensive resection of the gut and treated for prolonged periods with corticoids, had permanently an index between 100 and 120% without treatment.


[Alcohol block of the celiac plexus in severe visceral pain].

The authors present their own experience with percutaneous alcohol block of the coeliac plexus. Between April 1988 and December 1991 they used it in 22 patients. Except one patient the others suffered from severe pain of abdominal organs associated with carcinoma of the pancreas. The first four operations were made using angiography, the remainder under CT control. During evaluation of results two weeks after the intervention complete regression of pain was recorded in six patients. A partial effect was achieved in 11 patients, and the intervention failed in five patients. The intervention was repeated in four patients. The authors emphasize that the procedure is relatively simple and safe, and if successful, makes it possible to reduce or even eliminate opiates. It improves the quality of the remaining life of the patient.


[The effect of education on metabolic compensation in diabetics].

The authors evaluate the effect of two years intense individual education on the metabolic compensation of diabetics. They evaluate it in 611 patients with regard to the blood concentration of glycosylated haemoglobin (HbA1c). The improved compensation was most marked in diabetics treated by a combination of insulin and oral antidiabetics (by 2.3%); in the remaining groups treated with insulin alone, with diet alone and derivatives of sulphonyl urea by 1.0-1.4%. Individual education of diabetics, of sufficiently intense, contributes substantially to compensation and should be the basic working method in all diabetological surgeries. The prerequisite of success is a well trained diabetological nurse and dietitian.


[Combined therapy with insulin/gliquidone (Glurenorm) in type 2 diabetes after treatment failure using oral antidiabetic agents].

The authors evaluate treatment by a combination of insulin and gliquidone (Glurenorm) in 29 type 2 diabetics where long-term treatment with oral antidiabetics alone had failed. Within four months all patients were completely compensated from the metabolic aspect. HbA1c declined from 10.8 to 6.5, C peptide, on the other hand, increased from the original value of 1.2 ng/ml to 1.8 ng/ml. The authors did not observe any undesirable effects or hypoglycaemic states. Gliquidone is suitable for combined treatment because of its short-term effect; stimulation of endogenous secretion has a pulsed character and imitates an intensified regime. The prerequisite of success is a low dose of intermediary insulin to prevent inhibition of the central action of gliquidone.


[Indapamide in the treatment of hypertension in diabetes].

The authors treated 20 diabetics (14 men and 6 women) in an open clinical trial with indapamide (Arifon, Zorka Co.) for a period of three months, using a morning dose of 2.5 mg. In 10 patients with hypertension stage I in all normalization of the systolic pressure below 18.6 kPa and diastolic pressure below 12 kPa was achieved. Treatment of patients with hypertension stage II was not adequate in 6 patients. In the course of treatment metabolic compensation of diabetes (type 1 or type 2) did not deteriorate. No changes in the blood lipid spectrum and mineral metabolism were recorded. Indapamide is an antihypertensive drug suitable for treatment of mild hypertension in diabetics as monotherapy.


[Long-term treatment with an insulin pump. 3 years' experience].

The author treated since 1985 on a long-term basis (for more than one year) 228 diabetic patients with an insulin pump. She gives an account for her experience of three years' treatment of 32 diabetics type 1 and 2, incl. 5 treated already for a period of 5 years. Eight type 1 diabetics treated on account of a great lability of the disease are free from specific complications. In 10 type 1 diabetics treated on account of developing nephropathy and neuropathy the condition has stabilized and does not develop further. In 14 type 2 diabetics progression of complications which led to the indication of pump treatment did not occur. Treatment had the most favourable effect on sensitive neuropathy and incipient nephropathy where a reduction of proteinuria was recorded. From the total number of 228 patients treated on a long-term basis in 31, on failure of the pump, decompensation occurred. Five of these patients developed ketosis which called for hospitalization. Clinically severe hypoglycaemia was observed only once.


[The significance of circulating endothelial cells in type 2 diabetes].

The authors examined in 134 type 2 diabetics under the age of 60 years (mean age 54.5 years) the number of circulating endothelia. The results were compared with the number of circulating endothelia in 12 type 1 diabetics who were in a compensated state. The number of circulating endothelial increased with the degree of metabolic decompensation, the limital value of glycosylated haemoglobin (HbA1c) was 12%. In patients with a lower HbA1c value the number of circulating endothelia was still at the upper range of normal values. The highest values were recorded in diabetics with ketosis. The elevated number of circulating endothelia does not depend on the duration of diabetes, on the method of treatment or the patient's age. The finding of an elevated number of circulating endothelia correlates also with a higher cholesterol and triacylglycerol level. The authors consider the raised number of circulating endothelia a marker of endothelial damage and thread of the development of macroangiopathy.


[The effect of a single dose of Bisoprolol on changes in blood pressure and hemodynamic indicators in patients with mild hypertension].

The authors administered to 10 patients with mild hypertension a single dose of 10 mg bisoprolol (Concor-Merck) during bioimpedance control of changes of the cardiac index and peripheral vascular resistance after an interval of 3 and 24 hours following administration of the drug. In all patients administration of the drug led to a statistically significant drop of the blood pressure. In patients with a high cardiac output (group A, n = 6) the decline of blood pressure was due to a blocked increment of the cardiac output and a slight block of the peripheral vascular resistance. In the group with a low cardiac output and high peripheral vascular resistance (group B, n = 3) the drop of the blood pressure was caused by peripheral vascular dilatation, the cardiac output was influenced minimally. Bisoprolol did not affect the left ventricular systolic function.


[The effect of a single dose of Bisoprolol on changes in blood pressure and hemodymic indicators in patients with mild hypertension during loading].

The authors administered to 10 patients with mild hypertension a single dose of 10 mg bisoprolol (CONCOR-Merck) during bioimpedance control of changes of the cardiac index and peripheral vascular resistance during an isometric load after an interval of 3 and 24 hours following administration of the drug. In all patients administration of the drug led during the third hour to a statistically significant drop of the blood pressure after a load. Twenty-four hours after administration the drop was no longer statistically significant. In patients with a high cardiac index (group A, n = 6) the decline of blood pressure was due to a blocked increment of the cardiac output and a slight block of the peripheral vascular resistance. In the group with a low cardiac index and high peripheral vascular resistance (group B, n = 3) the drop of the blood pressure was less marked than in group A and it was due only to the blocked increment of the cardiac output. The increment of the peripheral vascular resistance was not influenced by the preparation. Bisoprolol did not affect the left ventricular systolic function.


[Determination of galactose eliminating capacity after intravenous administration--a liver function test].

The authors discuss a simple method for assessment of the galactose elimination capacity after intravenous administration of a 20% solution, total dose 0.5 g galactose/kg body weight. In six blood venous samples after termination of an infusion (after 25, 30, 35, 40, 45 and 50 minutes) from an inserted venous catheter after assessment of the enzymatic estimation of the galactose concentration in individual samples the elimination line of galactose is assessed as well as its point of intersection (t) with the time axis. By means of these data along with the data on the amount of injected galactose and the amount of galactose excreted in the urine the galactose elimination capacity is calculated. The method is suitable for evaluation and monitoring of the functional state of the liver. It reflects the functional mass of liver parenchyma and is therefore a quantitative test of liver function.


[A new agent--nitric oxide].

A review of findings pertaining to EDRF (endothelium derived relaxation factor) which proved to be nitric oxide, NO. After an account of the vasodilatating action of NO in the cardiovascular system the main attention is devoted to macrophages, the source of NO and to the formation of NO during activation of infections and during septic shock. NO participates also in the cytotoxicity of macrophages. NO may be the cause of hypotension in hepatic failure. Cumulation of endogenous inhibitors of NO formation in renal failure may be the cause of hypertension. The author analyzes other clinical effects of NO with regard to impotence and diabetes: NO stimulates insulin secretion from the B-cells of the islets of Langerhans. Attention is also drawn to the possible function of NO in the pituitary, in particular with regard to the arginine test which stimulates STH secretion.


[Iodine status and incidence of thyropathies in the Czech population].

Based on clinical experience on the rising incidence of some thyropathies in our population, the authors examined a random sample of the Prague population. They assessed and evaluated iodinuria, the sonographic finding of the thyroid gland, the palpation finding of the thyroid and a clinical examination which comprised a detailed case-history (a questionnaire checked during the examination) and a clinical and anthropometric examination. The results indicate that iodinuria (which reflects the iodine intake) reaches the recommended optimum (above 150 micrograms iodine/l) only in 11.4% of boys, 14% men, 6.3% girls and 5.4% women. A quite inadequate intake (less than 50 g iodine/l) was recorded in 13.2% boys, 15.2% men, 17% girls and 33.1% women. When evaluating the thyroid volume, an enlarged volume is found in 20.4-58.3% and on evaluation by palpation pathological changes are found in a considerable proportion of the examined population. The findings suggest that the iodine supply of the Prague population is inadequate and the incidence of abnormal findings on the thyroid gland is high. It will be necessary to verify these findings in other random population samples from other localities. If the adverse position will be confirmed, this will call for an urgent solution, i.e. a better iodine supply of the population.


[The importance of optimal iodine intake, the present status and perspectives in Slovakia].

The concentration of iodine was estimated in 667 urine specimens of boys and girls aged 6-18 years from 5 regions of Slovakia. Only about a half of all values (i.e. 48.43%) was found in the optimum range of 10-20 micrograms/dl, while 40.43% of values wore in the range of iodine deficiency (i.e. less than 10 mu/dl). In addition, there were 10.64% of high values (ie. more than 20 micrograms/dl). These results show that the intake of iodine appears to be 3-4 times higher than before the start of iodine prophylaxis in about 1950, but it still does not reach the optimum level. The increase of iodine intake would be achieved by the replacement of iodide (KI) with iodate (KIO3) which is much more stable. This prevents the looses of iodine from the salt which represent 50 to 75 percent of the original level within 1 to 1 and a half year.


[The risk for osteoporosis in persons treated with thyroid hormones].

Patients taking suppressive doses of thyroid hormones may have adverse effects from such treatment. To test conditions under which such treatment might be deleterious to bone, we studied a group of patients who had undergone thyroidectomy because of thyroid cancer 1 to 21 years previously and were treated with steady suppressive doses of exogenous thyroid hormone. The group consisted from 13 men, 20 premenopausal and 25 postmenopausal women. The level of serum tyroxin a trijodothyronin in average didn't differ from the control subjects; thyreostimulating hormone was significantly lower than in controls. Vertebral bone density (BMD) was significantly reduced and biochemical markers of bone formation and (osteocalcin and bone isoenzyme of alkaline phosphatase in serum) were significantly increased as compared with controls only in postmenopausal patients. Biochemical indices of bone resorption (urinary hydroxyproline and plasma tartrate resistant acid phosphatase activity) were significantly increased in premenopausal and also in postmenopausal women. In thyroid hormone treated women, biochemical indices of both bone resorption and bone formation correlated significantly negatively with serum TSH levels. The results suggest that in postmenopausal women there is no "safe" suppressive dose of thyroid hormone. Patients treated with thyroid hormone should be evaluated for a latent or early symptomatic stage of bone loss. The thyroid drugs used should consist of exact content of thyroid hormones, preferably thyroxin.


[Insulin resistance and arterial hypertension. Hyperinsulinism as a basic etiopathogenic factor in essential arterial hypertension and associated phenomena].

In 50 normotonic patients with type 2 diabetes (NIDDM) and controls matched for sex and age with NIDDM and hypertension a statistically significant difference was found as regards S-peptide values on fasting, cholesterol, triglycerides, BMI and atherogenic index (cholesterol/HDL, p < 0.01). C-peptide values correlated positively with values of the systolic and median BP and the atherogenic index in both groups. In normotonic diabetics there was also a positive correlation with the BMI and in hypertonic subjects with the triglyceride levels. The results confirm the hypothesis that in NIDDM there is a direct relationship between arterial hypertension, unfavourable lipid parameters and insulin resistance and compensatory hyperinsulinism resp. The authors discuss possible mechanisms by which hyperinsulinism mediates a rise of BP, hyperlipoproteinaemia, hyperglycaemia and hirsutism (hormonal metabolic syndrome X and 5H resp.). These phenomena are the main risk factors of cardiovascular diseases and lead via heart attacks and cerebrovascular attacks (IHD and stroke) to a high cardiovascular morbidity and mortality in our population. The morbidity and mortality is steadily increasing and thus we are among civilized countries among those with the highest morbidity and mortality.


[A laboratory test for the detection of androgen resistance using sex hormone-binding globulin].

A simple laboratory test for disclosure of peripheral androgen insensitivity has been suggested. The test is based on determination of sex hormone-binding globulin (SHBG) following single administration of testosterone preparation (Testoviron Depot, Schering, 2 mg/kg of body weight). The kinetics of SHBG response to exogenous testosterone was investigated first in a group of 5 healthy male volunteers. The highest highly significant decrease of SHBG level occurred 7th day after drug administration. The method of choice for SHBG determination is an immunoradiometric assay (IRMA). The test was used for a group of 15 children and young people suspected for androgen sensitivity disorder. In all cases, besides SHBG on days 0 and 7 testosterone, dihydrotestosterone and LH were measured, too. In three instances the response was negative: in the case of male Turner syndrome, with very low basal SHBG levels, in one case of confirmed diagnosis of testicular feminization and in the third case of suspected testicular feminization, which has not yet been concluded. In all other patients a significant decrease (in average to 62.8% of the basal level) was in agreement with clinical findings.


[Thyroid gland antibodies. Methods and clinical significance].

The author presents a brief account of the clinically most important antibodies against thyroid antigens (against thyroglobulin, against the microsomal fraction or thyroid peroxidase, against thyroid hormones and against TSH receptors). He describes the main ways of their assessment in serum and evaluates the practical contribution of their estimation or detection in clinical diagnostic practice concerning endocrinopathies. Usually these estimations are only auxiliary and do not replace functional thyroid tests. Antibodies against thyroglobulin and against the microsomal fraction are found most frequently (and in the highest concentrations) in thyropathies with an assumed autoimmune component, in particular in lymphocytic thyroiditis. The low specificity (they are as a rule present also in other thyroid diseases and also in clinically eufunctional subjects with and without goitre) due to the relatively low prevalence reduce the diagnostic value of the examination. The examination of antireceptor antibodies is important, in particular in the diagnosis of immunogenic hyperthyroidism. The prevalence of antibodies against thyroid hormones is low and their detection serves about all to elucidate cases where the patient's clinical status is not in agreement with assessment of thyroid hormones.