Reactive oxygen species and their role in the andrological factor of couple fertility.

Reactive oxygen species play a significant role in male fertility and infertility. They are essential for physiological processes, but when their concentration becomes excessive, they can be a cause of various sperm pathologies. Seminal leukocytes and pathologically abnormal sperm are the primary sources of oxygen radicals in ejaculate. They negatively affect sperm quality, including DNA fragmentation and sperm motility impairment. Addressing increased concentrations of reactive oxygen species involves various appropriate lifestyle modifications and measures, including the use of antioxidants, treatment of urogenital infections, management of varicocele, weight reduction, and others. In many cases, these interventions can lead to adjustments in the condition and improvement in sperm quality. Such improvements can subsequently lead to enhanced outcomes in assisted reproduction or even an increased likelihood of natural conception. In some instances, the need for donor sperm may be eliminated. However, a key factor is adhering to a sufficiently prolonged treatment, which requires patience on the part of both, the physician and the patient.

Reverse blood flow as an option in mandibular reconstruction using a two-segment fibula free flap.

Microsurgical reconstruction is currently considered a method of choice for the repair of soft tissue or bony defects in head and neck surgery. This technical note presents the use of a reverse flow technique in mandibular reconstruction with two segments of fibula free flap in a patient with bilateral pseudoarthrosis. In the standard procedure, both segments of the fibula are supplied by one donor vascular pedicle with normal antegrade blood flow. The approach presented here employs reverse flow in the distal segment of the fibula using a venous graft to create two vascular independent free fibula segments. Reverse flow in mandibular reconstruction represents an alternative option to support the success of microsurgical procedures in indicated cases.

Palaeoecological data indicates land-use changes across Europe linked to spatial heterogeneity in mortality during the Black Death pandemic.

The Black Death (1347-1352 CE) is the most renowned pandemic in human history, believed by many to have killed half of Europe's population. However, despite advances in ancient DNA research that conclusively identified the pandemic's causative agent (bacterium Yersinia pestis), our knowledge of the Black Death remains limited, based primarily on qualitative remarks in medieval written sources available for some areas of Western Europe. Here, we remedy this situation by applying a pioneering new approach, 'big data palaeoecology', which, starting from palynological data, evaluates the scale of the Black Death's mortality on a regional scale across Europe. We collected pollen data on landscape change from 261 radiocarbon-dated coring sites (lakes and wetlands) located across 19 modern-day European countries. We used two independent methods of analysis to evaluate whether the changes we see in the landscape at the time of the Black Death agree with the hypothesis that a large portion of the population, upwards of half, died within a few years in the 21 historical regions we studied. While we can confirm that the Black Death had a devastating impact in some regions, we found that it had negligible or no impact in others. These inter-regional differences in the Black Death's mortality across Europe demonstrate the significance of cultural, ecological, economic, societal and climatic factors that mediated the dissemination and impact of the disease. The complex interplay of these factors, along with the historical ecology of plague, should be a focus of future research on historical pandemics.

Fabrication of black aluminium thin films by magnetron sputtering.

Black aluminium thin films were prepared by direct current (DC) pulsed magnetron sputtering. The N2 concentration in the Ar-N2 mixture that was used as the deposition atmosphere was varied from 0 to 10%, and its impact on the film growth and optical properties was studied. A strong change in the film growth process was observed as a function of the N2 concentration. At a specific N2 concentration of ∼6%, the Al film growth process favoured the formation of a moth-eye-like antireflective surface. This surface morphology, which was similar to the structure of a cauliflower, is known to trap incident light, resulting in films with a very low reflectivity. A diffuse reflectivity lower than 4% was reached in the ultraviolet-visible-near infrared (UV-VIS-NIR) spectral range that corresponds to a value observed for an ultrahigh absorber. We found that for the preparation of black aluminium, the nitrogen content plays an important role in film formation and the resulting film morphology.

Cephalic tetanus presenting with bilateral facial palsy.

We discuss the case and differential diagnoses of an elderly man who presented with bilateral facial palsy. He had injured his forehead in the garden during a fall on his face and the open wound was contaminated by soil. He then presented to the emergency department with facial weakness causing difficulty speaking. The penny dropped when he started developing muscle spasms affecting his lower jaw a day after admission. It also became clear that he could not open his mouth wide (lock jaw). The combination of muscle spasms and lock jaw (trismus) made tetanus the most likely possibility, and this was proven when he had samples taken from his wound and analysed under the microscope, which showed Clostridium tetani bacilli. C. tetani spores are widespread in the environment, including in the soil, and can survive hostile conditions for long periods of time. Transmission occurs when spores are introduced into the body, often through contaminated wounds. Tetanus in the United Kingdom is rare, but can prove fatal if there is a delay in recognition and treatment.

Sources of cosmic dust in the Earth's atmosphere.

There are four known sources of dust in the inner solar system: Jupiter Family comets, asteroids, Halley Type comets, and Oort Cloud comets. Here we combine the mass, velocity, and radiant distributions of these cosmic dust populations from an astronomical model with a chemical ablation model to estimate the injection rates of Na and Fe into the Earth's upper atmosphere, as well as the flux of cosmic spherules to the surface. Comparing these parameters to lidar observations of the vertical Na and Fe fluxes above 87.5 km, and the measured cosmic spherule accretion rate at South Pole, shows that Jupiter Family Comets contribute (80 ± 17)% of the total input mass (43 ± 14 t d-1), in good accord with Cosmic Background Explorer and Planck observations of the zodiacal cloud.

Effective AC needleless and collectorless electrospinning for yarn production.

Nanofibrous materials are essential components for a wide range of applications, particularly in the fields of medicine and material engineering. These include protective materials, sensors, cosmetics, hygiene, filtration and energy storage. The most widely used and researched technology in these fields is electrospinning. This method for producing fibers yields highly promising results thanks to its versatility and simplicity. Electrospinning is employed in multiple forms, among which needle and needleless direct current (DC) variants are the most distinctive. The former is based on the generation of just one single jet from a nozzle; hence this fabrication process is not very productive. The latter uses the destabilization of free liquid surfaces by means of an electric field, which enhances the throughput since it produces numerous jets, emitted from the surfaces of rollers, spheres, strings and spirals. However, although some progress in total producibility has been achieved, the efficiency of the DC method still remains relatively low. A further drawback of DC electrospinning is that both variants need a collector, which makes it difficult to combine DC electrospinning easily with other technologies due to the presence of the high field strength within the entire spinning zone. This paper describes our experiments with AC electrospinning. We show that alternating current (AC) electrospinning based on a needleless spinning-electrode provides a highly productive smoke-like aerogel composed of nanofibers. This aerogel rises rapidly from the electrode like a thin plume of smoke, without any need for a collector. Our work shows that AC needleless electrospinning gains its efficiency and collector-less feature thanks to the creation of a perpetually charge-changing virtual counter-electrode composed of the nanofibers emitted. High-speed camera recordings demonstrate the formation mechanism of the nanofibrous plume, which is wafted by an electric wind. This wind's velocity field is experimentally investigated. One potential use of AC needleless electrospinning is demonstrated here by spinning it into a yarn.

[Surgical treatment of pulmonary embolism]. / Chirurgická lécba plicní embolie.

BACKGROUND: Surgical embolectomy is established method of treatment of pulmonary embolism. The aim of the study is to evaluate the experience with this procedure. PATIENTS AND METHODS: Twenty two patients, aged 22-77 years, were operated on in Centre of cardiovascular surgery and transplantation in Brno from 1999 to 2009. Nine patients suffered from massive pulmonary embolism with hemodynamic instability, 13 were stable. All the operations were performed in cardiopulmonary bypass with cross clampimg time 50.4 minutes on average. In six patients the retrograde perfusion via pulmonary veins were used. Emboli in the main trunk and/or in both pulmonary branches were found in 16 patients (72.7%). No macroscopic emboli were found in three patients, but they were flushed from the pulmonary vessels during the retrograde perfusion in two of them. Emboli or thrombi in cardiac atria or ventricles were detected in 8 patients simultaneously. RESULTS: Five patients died early after operation (mortality 22.7%). The mortality was different in the group of patients with massive pulmonary embolism and cardiogenic shock (44.4%) and with submassive embolism and hemodynamic stability (7.7%). CONCLUSION: Developments in surgical technique with retrograde perfusion offer removing of emboli not only from the pulmonary trunk and main branches, but also from the peripheral branches. It improves results and facilitates extension of indications for surgical treatment.

Dosimetry at an interim storage for spent nuclear fuel.

The Czech nuclear power plant Dukovany started its operation in 1985. All fuel spent from 1985 up to the end of 2005 is stored at a dry interim storage, which was designed for 60 CASTOR-440/84 casks. Each of these casks can accommodate 84 fuel assemblies from VVER 440 reactors. Neutron-photon mixed fields around the casks were characterized in terms of ambient dose equivalent measured by standard area dosemeters. Except this, neutron spectra were measured by means of a Bonner sphere spectrometer, and the measured spectra were used to derive the corresponding ambient dose equivalent due to neutrons.

Coronary artery bypass grafting in patients with left ventricular ejection fraction of 30% or less.

BACKGROUND: The results of a merely pharmacological therapy in patients with advanced left ventricular dysfunction are unsatisfactory. Coronary artery bypass grafting is frequently the only therapeutic option, but ventricular dysfunction is generally considered to be a risk factor. AIM: To find out the frequency of coronary artery bypass grafting and its outcome in patients with a ejection fraction of 30% or less who were operated on at a single institution. METHODS: Between January 1st, 1996 and October 30th, 1999, 90 patients (4.6% of all patients operated on due to of coronary artery disease) with EF of 30% or less underwent coronary artery bypass grafting. This group consisted of 12 women and 78 men at an average age of 60.2 +/- 9.4 years (range, 33 to 78 years); 75.6% patients were in functional class III or IV and 80.0% had three-vessel disease. On the average, 2.5 grafts per patient were implanted, the left internal mammary artery was used in 24.4% patients, and 10.0% of patients had cardiac surgery without cardiopulmonary bypass. RESULTS: Hospital mortality was 10%. The main cause of death was cardiac or multiorgan failure. Low cardiac output syndrome and supraventricular dysrrhythmias were the most common postoperative complications. Advanced age and low cardiac output syndrome were found to be risk factors of early mortality. Five other patients died during the follow-up (4 to 48 months). One- and three-year survival rate were 83.1% and 81.9%, respectively. Ejection fraction improved during the follow-up from 27.5% to 33.7%. The improvement was more pronounced in patients in whom preoperative end-diastolic diameter of the left ventricle was below 70 mm, and in patients with two and more hibernating segments on dobutamine stress echo. CONCLUSIONS: Successful results of surgical revascularization in patients with severe impairment of left ventricular function can be achieved by careful selection of patients (the presence of viable myocardium is necessary) and management. Early mortality and morbidity was higher than in patients with normal ventricular function. Age and low cardiac output syndrome were revealed as risk factors of early mortality. Long-term prognosis for hospital survivals was satisfactory. (Tab. 5, Fig. 1, Ref. 13.)

[Incidence of Borrelia in the common tick (Ixodes ricinus) in the area of the city of Brno]. / Výskyt borrélií v klísteti obecném (Ixodes ricinus) na území mesta Brna.

During the period between July and October 1988 more than 1000 ticks Ixodes ricinus were collected at 16 sites in the town of Brno and examined by indirect immunofluorescence (IFA) for the presence of Borrelia. The positivity of the tick population in 13 localities varied between 0.9-18.6%, ticks from three localities were negative. The results confirm the diffuse character of the presence of Borrelia in ticks I. ricinus in the urban environment and the possibility of infection of the urban population in the very town may be assumed.

[Occurrence of Borrelia antibodies in field hares (Lepus europaeus)]. / Výskyt borreliových protilátek u zajíce polního (Lepus europaeus).

Using the indirect haemagglutination reaction with an antigenic extract from Borrelia recurrentis, the author assessed in the hare the incidence of Borrelia antibodies, incl. antibodies against Borrelia burgdorferi, the causal agent of Lyme borreliosis, a multisystemic disease with natural foci, a disease transmitted mostly by ticks of the genus Ixodes. Sera of 113 hares from 11 localities in the CSSR examined by this method reacted in 41.6% by titres within the range from 1 : 16 to 1 : 512, only 26.5% sera reacted by titres of 1 : 64 and more. Positive values were recorded throughout the year with a maximum in the summer months, there was no age dependence, the incidence was more frequent in adults than juveniles (28.04% and 22.2% resp.). The mean positivity of the three most frequent localities was 28%, with a variation of +/- 5.3%. Despite the hitherto not proved incidence of Borrelia in positive subjects we may assume, based on crossed reactivity of Borrelia recurrentis and Borrelia burgdorferi and analogously with North American representatives of the hare family, the presence of this infectious agent also in the field hare.

[Borrelia sp. in the common tick (Ixodes ricinus) from the Prague area]. / Borrelia sp. v klísteti obecném (Ixodes ricinus) na území mesta Prahy.

In the course of 1988 almost 3000 ticks were collected from various localities on the territory of Prague and examined by the method of indirect immunofluorescence (IFA) for the presence of Borrelia. The immunity rate of ticks varies between 1.9-22.0%. Positive ticks were found also in some areas practically in the centre of the town. These findings indicate the possible contact of the Prague population with the infectious agent on the very territory of the town. The authors give a list of potential carrier animals on the territory of Prague.

[Incidence of the spirochete Borrelia burgdorferi in arthropods (Arthropoda) and antibodies in vertebrates (Vertebrata)]. / Výskyt spirochety Borrelia burgdorferi u clenovcu (Arthropoda) a protilátek u obratlovcu (Vertebrata).

The paper summarizes data on hitherto assembled findings of Spirochaeta burgdorferi, the causal agent of Lyme disease in arthropods and the incidence of antibodies in birds and mammals. The authors evaluate some vectors and reservoir animals, incl. possible carriers. Borrelia burgdorferi was found so far in 30 species of Arthropoda, 13 species of mites (Acarina), 15 species of flies(Diptera), two species of fleas (Siphonaptera). The role of insects as vectors was not proved so far. Antibodies were detected in eight species of birds (Aves, Passeriformes) and in 22 mammalian species: one species of marsupiales (Marsupialia), 3 species of carnivores (Carnivora), seven species of rodents (Rodentia), two species of rabbits and hares (Lagomorpha), in 8 species of even-toed ungulates (Artiodactyla) and one species of odd-toed ungulates (Perissodactyla). The great majority of species comes from the non-arctic area.