Mechano-Optical Switching of a Single Molecule with Doublet Emission

The ability to control the emission from single-molecule quantum emitters is an important step toward their implementation in optoelectronic technology. Phthalocyanine and derived metal complexes on thin insulating layers studied by scanning tunneling microscope-induced luminescence (STML) offer an excellent playground for tuning their excitonic and electronic states by Coulomb interaction and to showcase their high environmental sensitivity. Copper phthalocyanine (CuPc) has an open-shell electronic structure, and its lowest-energy exciton is a doublet, which brings interesting prospects in its application for optospintronic devices. Here, we demonstrate that the excitonic state of a single CuPc molecule can be reproducibly switched by atomic-scale manipulations permitting precise positioning of the molecule on the NaCl ionic crystal lattice. Using a combination of STML, AFM, and ab initio calculations, we show the modulation of electronic and optical bandgaps and the exciton binding energy in CuPc by tens of meV. We explain this effect by spatially dependent Coulomb interaction occurring at the molecule-insulator interface, which tunes the local dielectric environment of the emitter.

Scintigraphic evaluation of salivary gland function in thyroid cancer patients after radioiodine remnant ablation

Radioiodine (¹³¹I, RAI) has traditionally been used in thyroid cancer treatment but its benefit should be balanced against possible risks. Among them, salivary gland dysfunction has often been discussed, although the reported data have been inconsistent. The aim of our prospective study was to evaluate salivary gland function in 31 thyroidectomised patients (6 men, 25 women; median age 52 yr) before and 4–6 months after RAI remnant ablation (RRA), using activity of 3.7 GBq ¹³¹I‐NaI. Salivary gland uptake and excretion fractions were quantitatively assessed with ^99mTc – pertechnetate salivary gland scintigraphy. Pre‐ and post‐treatment values were compared using Wilcoxon signed rank test. No statistically significant difference in the pre‐ and post‐treatment values was observed in parotid or submandibular glands uptake, or in the parotid or submandibular excretion fractions. The calculated power for minimum relevant difference of 25% with the sample size of 31 ranged between 86% and 96% for the individual variables, making our negative results reasonably reliable. The results suggest that RRA with the most commonly used activity of 3.7 GBq has no important impact on salivary gland function. Therefore, the concerns about putative salivary gland functional deterioration following RRA are probably unjustified.

Linking Plant Functional Ecology to Island Biogeography

The study of insular systems has a long history in ecology and biogeography. Island plants often differ remarkably from their noninsular counterparts, constituting excellent models for exploring eco-evolutionary processes. Trait-based approaches can help to answer important questions in island biogeography, yet plant trait patterns on islands remain understudied. We discuss three key hypotheses linking functional ecology to island biogeography: (i) plants in insular systems are characterized by distinct functional trait syndromes (compared with noninsular environments); (ii) these syndromes differ between true islands and terrestrial habitat islands; and (iii) island characteristics influence trait syndromes in a predictable manner. We are convinced that implementing trait-based comparative approaches would considerably further our understanding of plant ecology and evolution in insular systems.

Charge Carrier Injection Electroluminescence with CO-Functionalized Tips on Single Molecular Emitters

We investigate electroluminescence of single molecular emitters on NaCl on Ag(111) and Au(111) with submolecular resolution in a low-temperature scanning probe microscope with tunneling current, atomic force, and light detection capabilities. The role of the tip state is studied in the photon maps of a prototypical emitter, zinc phthalocyanine (ZnPc), using metal and CO-metal tips. CO-functionalization is found to have an impact on the resolution and contrast of the photon maps due to the localized overlap of the p-orbitals on the tip with the molecular orbitals of the emitter. The possibility of using the same CO-functionalized tip for tip-enhanced photon detection and high resolution atomic force is demonstrated. We study the electroluminescence of ZnPc, induced by charge carrier injection at sufficiently high bias voltages. We propose that the distinct level alignment of the ZnPc frontier orbitals with the Au(111) and Ag(111) Fermi levels governs the primary excitation mechanisms as the injection of electrons and holes from the tip into the molecule, respectively. These findings put forward the importance of the tip status in the photon maps and contribute to a better understanding of the photophysics of organic molecules on surfaces.

Dual Tracer 99mTc-Pertechnetate/99mTc-MIBI Dual-Time-Point SPECT/CT Parathyroid Gland Assessment Regarding to Parathyroid Gland Size and Biochemical Parameters - Two Years Single Imaging Centre Experience

INTRODUCTION

Preoperative parathyroid imaging is inevitable part of focused parathyroid surgery. The aim of our study was assessment of parathyroid scintigraphy diagnostic accuracy regarding to size and metabolic parameters of hyperfunctioning parathyroid tissue.

MATERIAL AND METHODS

Parathyroid scintigraphy for suspected primary hyperparathyroidism was performed in 95 patients during years 2015 and 2016. Of them, 75 patients with known clinical outcome (40 underwent surgery, 35 had documented laboratory follow-up) were further retrospectively evaluated. The performance of dual tracer 99mTc-pertechnetate and 99mTc-MIBI subtraction and dual-time-point 99mTc-MIBI imaging with SPECT/CT was analysed. Serum parathyroid hormone (PTH), calcaemia, ionized calcaemia and phosphataemia and ultrasound detected adenoma volume and largest diameter in false negative and true positive findings were compared using Mann-Whitney test.

RESULTS

Sensitivity and specificity of parathyroid scintigraphy was 74.5% and 95.8%, respectively. NPV was 63.8% and PPV 97.4%. Hyperfunctioning parathyroid tissue detectability was almost significantly associated with hypophosphataemia and PTH levels.

CONCLUSION

Parathyroid scintigraphy provides high sensitivity and superior specificity in parathyroid adenoma location, nevertheless the diagnostic accuracy tends to decline in smaller adenomas and in less metabolically active parathyroid tissue causing only subtle biochemical changes. 18F-Fluorocholine PET/CT or 3D SPECT/CT subtraction should be a reasonable option for those cases.

The legacy of initial sowing after 20 years of ex-arable land colonisation

Priority effects provide an advantage to early establishing species and are thought to significantly affect the course of succession. We conducted a 20-year long experiment sowing high- and low-diversity mixtures in an ex-arable field. We ask how long the effect of sowing persists and which sown species affect the course of succession. The experiment was established in the Czech Republic in five replicate blocks, each containing three random 10 × 10 m plots with three treatments: natural colonisation, sowing low- and high-diversity seed mixtures. The species cover was annually estimated in 12 permanent 1 m² quadrates within each plot. To identify the effects of sowing, we used an innovative method analysing the data separately for each year using Redundancy analysis (RDA) with identity of sown species as explanatory variables. In the first year, the effect of sowing was small; the peak of explained variability occurred between third and fifth year. The legacy of sowing was detectable in the natural colonisers for 18 years and in the sown species for the whole 20-year period. For some species, the difference between the plots where they were and were not sown remained significant for the whole 20-year period (e.g. Lathyrus pratensis) although the plots were adjacent and the area was mown with the same machine. Other ones (e.g. Trisetum flavescens) colonised all the plots evenly. The long-lasting effect of the initial sowing confirms contingency of successional pathway on the propagule pressure in the time of start of succession due to the priority effects.

Correction to: Nitrogen acquisition, net production and allometry of Alnus fruticosa at a young moraine in Koryto Glacier Valley, Kamchatka, Russian Far East

In the original publication of the article, one of the author names was published incorrectly as "Jiri Dorezal". The correct name is Jiří Doležal.

Increased spruce tree growth in Central Europe since 1960s

Tree growth response to recent environmental changes is of key interest for forest ecology. This study addressed the following questions with respect to Norway spruce (Picea abies, L. Karst.) in Central Europe: Has tree growth accelerated during the last five decades? What are the main environmental drivers of the observed tree radial stem growth and how much variability can be explained by them? Using a nationwide dendrochronological sampling of Norway spruce in the Czech Republic (1246 trees, 266 plots), novel regional tree-ring width chronologies for 40(±10)- and 60(±10)-year old trees were assembled, averaged across three elevation zones (break points at 500 and 700m). Correspondingly averaged drivers, including temperature, precipitation, nitrogen (N) deposition and ambient CO₂ concentration, were used in a general linear model (GLM) to analyze the contribution of these in explaining tree ring width variability for the period from 1961 to 2013. Spruce tree radial stem growth responded strongly to the changing environment in Central Europe during the period, with a mean tree ring width increase of 24 and 32% for the 40- and 60-year old trees, respectively. The indicative General Linear Model analysis identified CO₂, precipitation during the vegetation season, spring air temperature (March-May) and N-deposition as the significant covariates of growth, with the latter including interactions with elevation zones. The regression models explained 57% and 55% of the variability in the two tree ring width chronologies, respectively. Growth response to N-deposition showed the highest variability along the elevation gradient with growth stimulation/limitation at sites below/above 700m. A strong sensitivity of stem growth to CO₂ was also indicated, suggesting that the effect of rising ambient CO₂ concentration (direct or indirect by increased water use efficiency) should be considered in analyses of long-term growth together with climatic factors and N-deposition.

Pleural empyema - single center experience

INTRODUCTION

Retrospective analysis of a group of patients treated for pleural empyema in the Department of Surgery, University Hospital Pilsen, over the last ten years.

METHOD

We evaluated a group of patients treated for pleural empyema in the Department of Surgery, University Hospital in Pilsen, during the period 2007-2016. We focused on the demographic data of this group, the causes of empyema in these patients, surgical procedures performed in connection with empyema, the microbial species found in empyema, and, last but not least, on morbidity and lethality.

RESULTS

We treated 103 patients with pleural empyema during the above period - 80 men (77.7%) and 23 women (22.3%) aged 23-83 years (average age 59.4 years). 64 patients had a history of surgical or invasive procedure (62.1%). The length of history was traceable in 55 patients (53.4%) and was 23.1 days on average, remaining unclear in the rest of the group. 1/3 of cases were metapneumonic empyemas, 1/3 postoperative empyemas and 1/3 of the cases were due to other reasons. The most commonly cultivated bacterial genus was Streptococcus, species Staphylococcus aureus. The most common surgery was chest drainage (51%). 13 patients died (lethality 12.6%) after surgery, the most common cause of death being sepsis; postoperative morbidity was 34%.

CONCLUSION

Pleural empyema is a serious condition with very high morbidity and lethality. Surgical procedures done to manage empyema are associated with a very high risk of necessary reoperation. Positive mycological culture from empyema seems to be associated with a higher risk of complications and death. Key words: empyema - thoracic drainage - thoracotomy - lung decortication - videothoracoscopy.

Splenectomy in patients older than 65 years - a single-center experience

INTRODUCTION

Despite current efforts at the most conservative approach possible to splenic injury, splenectomy remains a relatively common surgical procedure. Indications for splenectomy, however, are not limited to spleen injury. In senior patients in particular, non-traumatic reasons for splenectomy becomemore frequent. In addition, previous studies have indicated a relatively wide range of complications and lethality in splenectomized patients without taking into account the age aspect. Within the scope of geriatric surgery, this study deals with splenectomy in elderly patients and is based on retrospectively evaluated experience of our clinic.

METHOD

We studied a group of patients older than 65 years having undergone splenectomy at our institutionover the past 11 years. For each patient, the demographics, the reason for splenectomy, the mechanism of injury (if any), the degree of spleen damage, co-morbidities, the length of hospital stay, complications and lethality were evaluated. A group of patients operated on due tospleen trauma and the other group operated on for other reasons were analysed separately. Attention was paid to the reasons leading to splenectomy in the non-traumatic patients. Complications and lethality rate were evaluated in relation to the individual patient groups.

RESULTS

269 splenectomies were performed in our clinic between 2006 and 2016. Of these, only 57 (21.2%) were carried out in patients older than 65 years (32 men and 25 women aged 6590, mean age 73.6). Splenectomy was even rarer in association with splenic trauma:it was performed in only 13 senior patients. Other causes leading to splenectomy in elderly patients were: perioperative spleen injury (17 patients), gangrene, septic activation or spontaneous rupture of the spleen (10 patients), splenectomy during an operation on another organ (8 patients), splenomegaly (5 patients) and splenic artery aneurysm (4 patients). Lethality in the entire group was 29.8%, the percentage of complications was 57.9%; however, circumstances leading to splenectomy and also potential co-morbidities played a significant role. The average length of hospitalization in the entire group was 20.3 days.

CONCLUSIONS

Splenectomy in patients over 65 years of age is associated with a high risk of complications and very high lethality. However, senior patients after splenectomy for monotrauma and those after elective splenectomy have a very good prognosis. Key words: geriatric surgery splenic rupture - splenectomy.

Is the scaling relationship between carbohydrate storage and leaf biomass in meadow plants affected by the disturbance regime?

BACKGROUND AND AIMS

Below-ground carbohydrate storage is considered an adaptation of plants aimed at regeneration after disturbance. A theoretical model by Iwasa and Kubo was empirically tested which predicted (1) that storage of carbohydrates scales allometrically with leaf biomass and (2) when the disturbance regime is relaxed, the ratio of storage to leaf biomass increases, as carbohydrates are not depleted by disturbance.

METHODS

These ideas were tested on nine herbaceous species from a temperate meadow and the disturbance regime was manipulated to create recently abandoned and mown plots. Just before mowing in June and at the end of the season in October, plants with below-ground organs were sampled. The material was used to assess the pool of total non-structural carbohydrates and leaf biomass.

KEY RESULTS

In half of the cases, a mostly isometric relationship between below-ground carbohydrate storage and leaf biomass in meadow plants was found. The ratio of below-ground carbohydrate storage to leaf biomass did not change when the disturbance regime was less intensive than that for which the plants were adapted.

CONCLUSIONS

These findings (isometric scaling relationship between below-ground carbohydrate storage and leaf biomass; no effect of a relaxed disturbance regime) imply that storage in herbs is probably governed by factors other than just the disturbance regime applied once in a growing season.

Diversity and feeding strategies of soil microfauna along elevation gradients in Himalayan cold deserts

High-elevation cold deserts in Tibet and Himalaya are one of the most extreme environments. One consequence is that the diversity of macrofauna in this environment is often limited, and soil microorganisms have a more influential role in governing key surface and subsurface bioprocesses. High-elevation soil microfauna represent important components of cold ecosystems and dominant consumers of microbial communities. Still little is known about their diversity and distribution on the edge of their reproductive and metabolic abilities. In this study, we disentangle the impact of elevation and soil chemistry on diversity and distribution of rotifers, nematodes and tardigrades and their most frequent feeding strategies (microbial filter-feeders, bacterivores, fungivores, root-fungal feeders, omnivores) along two contrasting altitudinal gradients in Indian NW Himalaya (Zanskar transect from 3805 to 4714 m a.s.l.) and southwestern Tibet (Tso Moriri transect from 4477 to 6176 m a.s.l.), using a combination of multivariate analysis, variation partitioning and generalized additive models. Zanskar transect had higher precipitation, soil moisture, organic matter and available nutrients than dry Tso Moriri transect. In total, 40 species of nematodes, 19 rotifers and 1 tardigrade were discovered. Species richness and total abundance of rotifers and nematodes showed mid-elevation peaks in both investigated transects. The optimum for rotifers was found at higher elevation than for nematodes. Diversity and distribution of soil microfauna was best explained by soil nitrogen, phosphorus and organic matter. More fertile soils hosted more diverse and abundant faunal communities. In Tso Moriri, bacterivores represented 60% of all nematodes, fungivores 35%, root-fungal feeders 1% and omnivores 3%. For Zanskar the respective proportions were 21%, 13%, 56% and 9%. Elevational optima of different feeding strategies occurred in Zanskar in one elevation zone (4400–4500 m), while in Tso Moriri each feeding strategy had their unique optima with fungivores at 5300 m (steppes), bacterivores at 5500 m (alpine grassland), filter-feeders at 5600 m and predators and omnivores above 5700 m (subnival zone). Our results shed light on the diversity of microfauna in the high-elevation cold deserts and disentangle the role of different ecological filters in structuring microfaunal communities in the rapidly-warming Himalayas.

Fungal root symbionts of high-altitude vascular plants in the Himalayas

Arbuscular mycorrhizal fungi (AMF) and dark septate endophytes (DSE) form symbiotic relationships with plants influencing their productivity, diversity and ecosystem functions. Only a few studies on these fungi, however, have been conducted in extreme elevations and none over 5500 m a.s.l., although vascular plants occur up to 6150 m a.s.l. in the Himalayas. We quantified AMF and DSE in roots of 62 plant species from contrasting habitats along an elevational gradient (3400-6150 m) in the Himalayas using a combination of optical microscopy and next generation sequencing. We linked AMF and DSE communities with host plant evolutionary history, ecological preferences (elevation and habitat type) and functional traits. We detected AMF in elevations up to 5800 m, indicating it is more constrained by extreme conditions than the host plants, which ascend up to 6150 m. In contrast, DSE were found across the entire gradient up to 6150 m. AMF diversity was unimodally related to elevation and positively related to the intensity of AMF colonization. Mid-elevation steppe and alpine plants hosted more diverse AMF communities than plants from deserts and the subnival zone. Our results bring novel insights to the abiotic and biotic filters structuring AMF and DSE communities in the Himalayas.

[Traumatic pneumothorax - diagnosis and treatment of 322 cases over a five-year period]

INTRODUCTION

Retrospective analysis of a set of patients treated for traumatic pneumothorax in the Trauma Centre of Teaching Hospital in Pilsen over a period of five years.

METHOD

In total, 322 patients with traumatic pneumothorax were treated in the study period 20122016. The set included subjects whose injury fell within the definition of traumatic pneumothorax and who underwent either primary treatment or secondary transport to the Trauma Centre following basic treatment in another health facility on the day that the trauma occurred. The exclusion criterion was a pneumothorax <1 cm; in addition, patients with inconclusive findings from imaging screening were not included in the set. Basic demographic information, the mechanism, type and laterality of the traumatic pneumothorax, the Injury Severity Score, associated injuries, diagnostic procedures, timing, method and outcome of the treatment, as well as any complications and reoperations, were identified in the set. Other assessed information included deaths of patients with traumatic pneumothorax, including the cause and time of death in relation to the time of admission to the Trauma Centre.

RESULTS

The vast majority of traumatic pneumothoraces (94.1%) occurred as a result of blunt chest trauma, car accidents being the most common mechanism (about 28%). Closed pneumothoraces dominated (91.3%). Traumatic pneumothorax was part of a polytrauma in about one half of the injured. The average Injury Severity Score within the set was 20 points. Traumatic pneumothorax was diagnosed in more than three quarters of the patients based on clinical examination and computed tomography. The most common therapeutic procedure was drainage of the relevant pleural cavity (259 patients - 80.5%). Almost two thirds of surgical procedures were carried out within 1 hour of admission to the Trauma Centre. Complications associated with traumatic pneumothorax treatment were reported in 10.2% of the cases, and 33 reoperations were carried out. 15 patients (4.7%) in the set died, out of which 12 on the day of the trauma, all of them as a result of decompensated traumatic shock.

CONCLUSION

Traumatic pneumothorax is a relatively frequent type of chest trauma found in up to half of the patients with chest trauma as part of a polytrauma. It usually occurs as closed pneumothorax as a result of blunt chest trauma. The diagnostic process is based on clinical examination and chest radiogram. However, ultrasound examination could be an alternative to chest radiogram in emergency situations. Computed tomography is the method of first choice for more serious traumas and inconclusive findings. To manage this condition, proper drainage of the relevant pleural cavity is sufficient in the vast majority of the patients. With timely diagnosis and adequate therapeutic intervention, the prognosis for patients with traumatic pneumothorax is favourable.Key words: traumatic pneumothorax - diagnosis - chest drainage.

[Penetrating chest trauma - experience of the Pilsen University Hospital Trauma Centre]

INTRODUCTION

Retrospective analysis of a set of patients treated for penetrating chest trauma in the Trauma Centre at University Hospital Pilsen over seventeen years.

METHOD

Overall, 96 injured with penetrating chest trauma were treated in the study period 2000-2016. Basic demographics, the mechanism, type, location and extent of the penetrating chest trauma, Injury Severity Score, existence of associated injuries, diagnostic procedures, timing and method of the chest trauma treatment as well as any complications and reoperations were identified in the set. Other collected information included deaths of the injured, and the cause and time of death in relation to the time of admission to the Trauma Centre.

RESULTS

The most common mechanism of injury was attack by a stabbing weapon (54%) and the most common type of injury was pulmonary laceration (33%). The average Injury Severity Score within the set was 24 points. The most common therapeutic procedure was pleural cavity drainage (47 patients), and less than 40% of the cases required revision surgery by means of thoracotomy or sternotomy. One patient died immediately after being admitted to the Trauma Centre without a chance to apply any therapy; three other patients died during resuscitative thoracotomy or laparotomy. Post-operative complications occurred in 13 patients (13.5%) and required 14 reoperations.

CONCLUSIONS

The diagnostic and therapeutic algorithm of penetrating chest trauma is primarily determined by the condition of the injured. Adequate drainage of the relevant pleural cavity is sufficient to treat one half of the patients; on the other hand, 40% of traumas, injuries of the heart, large vessels and gunshot wounds in particular, require urgent revision surgery by means of thoracotomy or sternotomy. If the injured patient is transported to a specialized centre for timely treatment, the prognosis of penetrating chest traumas is quite favourable.Key words: penetrating chest trauma - diagnosis - chest drainage - thoracotomy - sternotomy.

ASSESSMENT OF THE LOCAL EXPOSURE OF SKIN ON HANDS OF NUCLEAR MEDICINE WORKERS HANDLING 18F-LABELLED RADIOPHARMACEUTICALS: PRELIMINARY CZECH STUDY

The article summarises some preliminary results of the assessment of the exposure of hands of workers manipulating ¹⁸F-labelled radiopharmaceuticals based on personal monitoring at two nuclear medicine clinics in the Czech Republic. The measurements were carried out using special thermoluminescence dosemeters the readings of which could be interpreted in terms of the personal dose equivalent H_p(0.07) approximating the equivalent dose to the skin at various locations on the surface of both hands. The results have shown that out of 21 workers monitored, ∼43 % (preparation and applications of radiopharmaceuticals) may reach an exposure equal to three-tenth of the annual dose limit to the skin. At the same time, it can also be concluded that in ∼10 % cases of workers, the relevant dose limit may be exceeded.

[The Influence of Palliative Chemotherapy on the Quality of Life of Patients with Gastric Cancer]

BACKGROUND

Gastric cancer is a malignant disease with a poor prognosis. The incidence of gastric cancer in the Czech Republic in 2013 was 14.34 cases per 100,000 citizens. Unfortunately, most patients are dia-gnosed with advanced stage disease and therefore undergo palliative treatment. Some patients undergo surgery and a very small percentage undergo palliative chemotherapy. The five year survival rate for those with advanced gastric cancer ranges from 5-15%.

METHODS

This is a prospective study of patients undergoing chemotherapy for advanced gastric cancer. The aim was to assess the quality of life of those undergoing chemotherapy.

RESULTS

The results showed that chemotherapy reduced the quality of life for these patients.

DISCUSSION

Although palliative chemotherapy prolonged time to progression, it had little impact on overall survival. Conversely, chemotherapy reduced quality of life. Thus, clinicians and patients must decide whether to begin palliative chemotherapy. The final decision should be made by the patient after discussion with the treating clinician.

CONCLUSION

Treatment of patients with gastric cancer must be undertaken on an individual basis. Those undergoing palliative treatment must play an active role in the decision process regarding chemotherapy and assess the potential benefits and drawbacks. Because chemotherapy treatment has a detrimental effect on quality of life, the decision should be based on factors that predict the likely therapeutic effect of chemotherapy. A definitive decision can then be made as to whether chemotherapy is indicated.

KEY WORDS

gastric cancer - palliative chemotherapy - chemotherapy - quality of life - WHOQOL-BREFThis study was supported by grant of Internal Grant Agency of the Czech Ministry of Health No. NS14227-3.The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study.The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.Submitted: 10. 1. 2016Accepted: 8. 6. 2016.

The Root-Associated Microbial Community of the World's Highest Growing Vascular Plants

Upward migration of plants to barren subnival areas is occurring worldwide due to raising ambient temperatures and glacial recession. In summer 2012, the presence of six vascular plants, growing in a single patch, was recorded at an unprecedented elevation of 6150 m.a.s.l. close to the summit of Mount Shukule II in the Western Himalayas (Ladakh, India). Whilst showing multiple signs of stress, all plants have managed to establish stable growth and persist for several years. To learn about the role of microbes in the process of plant upward migration, we analysed the root-associated microbial community of the plants (three individuals from each) using microscopy and tagged amplicon sequencing. No mycorrhizae were found on the roots, implying they are of little importance to the establishment and early growth of the plants. However, all roots were associated with a complex bacterial community, with richness and diversity estimates similar or even higher than the surrounding bare soil. Both soil and root-associated communities were dominated by members of the orders Sphingomonadales and Sphingobacteriales, which are typical for hot desert soils, but were different from communities of temperate subnival soils and typical rhizosphere communities. Despite taxonomic similarity on the order level, the plants harboured a unique set of highly dominant operational taxonomic units which were not found in the bare soil. These bacteria have been likely transported with the dispersing seeds and became part of the root-associated community following germination. The results indicate that developing soils act not only as a source of inoculation to plant roots but also possibly as a sink for plant-associated bacteria.

Is radioiodine administration in patients with papillary thyroid multifocal microcarcinoma unnecessary?

Radioiodine (RAI) has played a crucial role in differentiated thyroid cancer treatment for more than 60years. However, the use of RAI administration in patients with papillary thyroid microcarcinoma (even multifocal) is now being widely discussed and often not recommended. In accordance with European consensus, and contrary to the American Thyroid Association (ATA) guidelines, we recently performed RAI thyroid remnant ablation in a patient with differentiated papillary multifocal microcarcinoma. The post-therapeutic whole-body scan and SPECT/CT revealed the real and unexpected extent of disease, with metastases to upper mediastinal lymph nodes. This finding led to the patient’s upstaging from stage I to stage IVa according to the American Joint Committee on Cancer/International Union Against Cancer criteria.

Gardening in the zone of death: an experimental assessment of the absolute elevation limit of vascular plants

Vascular plants in the western Tibetan Plateau reach 6000 m-the highest elevation on Earth. Due to the significant warming of the region, plant ranges are expected to shift upwards. However, factors governing maximum elevational limits of plant are unclear. To experimentally assess these factors, we transplanted 12 species from 5750 m to 5900 m (upper edge of vegetation) and 6100 m (beyond range) and monitored their survival for six years. In the first three years (2009–2012), there were plants surviving beyond the regional upper limit of vegetation. This supports the hypothesis of dispersal and/or recruitment limitation. Substantial warming, recorded in-situ during this period, very likely facilitated the survival. The survival was ecologically a non-random process, species better adapted to repeated soil freezing and thawing survived significantly better. No species have survived at 6100 m since 2013, probably due to the extreme snowfall in 2013. In conclusion, apart from the minimum heat requirements, our results show that episodic climatic events are decisive determinants of upper elevational limits of vascular plants.

Some Like it High! Phylogenetic Diversity of High-Elevation Cyanobacterial Community from Biological Soil Crusts of Western Himalaya

The environment of high-altitudinal cold deserts of Western Himalaya is characterized by extensive development of biological soil crusts, with cyanobacteria as dominant component. The knowledge of their taxonomic composition and dependency on soil chemistry and elevation is still fragmentary. We studied the abundance and the phylogenetic diversity of the culturable cyanobacteria and eukaryotic microalgae in soil crusts along altitudinal gradients (4600-5900 m) at two sites in the dry mountains of Ladakh (SW Tibetan Plateau and Eastern Karakoram), using both microscopic and molecular approaches. The effects of environmental factors (altitude, mountain range, and soil physico-chemical parameters) on the composition and biovolume of phototrophs were tested by multivariate redundancy analysis and variance partitioning. Both phylogenetic diversity and composition of morphotypes were similar between Karakorum and Tibetan Plateau. Phylogenetic analysis of 16S rRNA gene revealed strains belonging to at least five genera. Besides clusters of common soil genera, e.g., Microcoleus, Nodosilinea, or Nostoc, two distinct clades of simple trichal taxa were newly discovered. The most abundant cyanobacterial orders were Oscillatoriales and Nostacales, whose biovolume increased with increasing elevation, while that of Chroococales decreased. Cyanobacterial species richness was low in that only 15 morphotypes were detected. The environmental factors accounted for 52 % of the total variability in microbial data, 38.7 % of which was explained solely by soil chemical properties, 14.5 % by altitude, and 8.4 % by mountain range. The elevation, soil phosphate, and magnesium were the most important predictors of soil phototrophic communities in both mountain ranges despite their different bedrocks and origin. The present investigation represents a first record on phylogenetic diversity of the cyanobacterial community of biological soil crusts from Western Himalayas and first record from altitudes over 5000 m.

[Predictive and prognostic factors of gastric cancer]

INTRODUCTION

Gastric cancer is a frequent malignant disease with poor prognosis. Most patients undergo only palliative treatment. Chemotherapy is another alternative but its effect differs in individual patients.

METHOD

This is retrospective study. We enrolled 54 patients (N=54) according to the inclusion criteria. We performed quantification of gene expression of selected genes and some microRNA from tumour tissue, which was used for the diagnosis. Statistical analysis of the data was performed.

RESULTS

We demonstrated a predictive value of gene expression of thynidylate synthase in tumour tissue for a therapeutic effect of chemotherapy based on 5-Fluorouracil or Capecitabine. At the same time, we demonstrated a predictive value of miR181, miR150, mir192 and miR342 microRNA levels from the tumour tissue. In addition, we succeeded to demonstrate a predictive value of miR221, miR224, miR520 and miR375 microRNA levels for a therapeutic effect of chemotherapy based on platinum derivates.

CONCLUSION

Thanks to the use of efficient therapy predictors, we can distinguish those patients who will profit from chemotherapy from patients where an effect cannot be expected. Thanks to personified oncology therapy the quality of life of some patients can be improved while reducing the costs of the therapy by avoiding inefficient chemotherapy. Only an early diagnosis of gastric cancer can reverse the adverse prognosis of patients with this disease.

KEY WORDS

gastric cancer - microRNA - prognostic markers - predictive markers.