Felhagyott alföldi homoktalajok mikrobiális közösség összetételének, biomasszájának és aktivitásának vizsgálata. = Microbial community structure, biomass and activity in sandy soils of abandoned fields of the Great Plain

A korábban művelt, de felhagyott területek ökológiai helyreállítása gazdasági és ökológiai szempontból is kívánatos lenne. A homokpuszta gyepek restaurációjának módszereit a talajban zajló tápanyag-dinamikai és az azzal összefüggő mikrobiális tevékenységek szempontjából tanulmányoztuk. A kezelések célja a nitrogén immobilizációjának elősegítésén keresztül a másodlagos szukcesszió felgyorsítása volt. A szénforrás-kezelések hatására a talajok mikrobiális biomasszája megnőtt. A nitrogén hozzáférhetőségét a kezelések csökkentették, ezáltal a gyomnövények biomasszája is lecsökkent, de ez nem vezetett szükségszerűen a natív növényfajok abundanciájának növekedéséhez. A természetes növényzet előretörését csak azokon a területeken figyeltük meg, ahol jelentős mennyiségű propagulum-forrás volt a talajban. A kombinált kezelések (kaszálás, C-forrás-kezelés, felülvetés természetes növényzet magjaival) növelték a természetes gyepi növények abundanciáját, a felvehető N tartalom csökkenése mellett. A bolygatatlan gyepterület mikrobiális közösségének stabilitását a bolygatott területtel szemben alátámasztotta a K-stratégista baktériumok nagyobb abundanciája, és a közösség struktúrájának kisebb szezonális változása, vagyis a bolygatatlan élőhely talajmikrobiális közössége nagyobb rezilienciával rendelkezett, mint a bolygatott. Ezek az eredmények fontos előrelépést jelentenek a művelésből kivont területeken a természetes növénytársulásokhoz hasonló növényzet kialakításában. | Ecological restoration of abandoned fields is favoured both in economic and ecological point of view. The restoration methodology of native sand grassland plant communities was studied focusing on soil nutrient dynamics and related microbiological processes. The aim of C amendments and other treatments was to promote microbial N immobilisation and through this to accelerate secondary succession. Carbon treatments (sawdust and sucrose) resulted in a significant increase in microbial biomass C and biomass N by approximately 20 percent. N availability was reduced significantly by C amendments, and the weed biomass decreased as well, but the abundance of native species was not observed in most cases. Native vegetation advanced only at sites having in appropriate amount of propagules in soils. Sawdust used in high rate can be unfavourable in long term resulting net N mineralisation through the priming effect. Combined treatments (mowing, C addition, reseeding by native species) increased the abundance of natural elements, whereas the available nutrients decreased. The higher level of stability of the soil microbial community at natural grassland against the disturbed sites was supported by the larger abundance of K-strategist bacteria and also the smaller seasonal change, therefore the microbial community had greater resilience at undisturbed grassland site than that had at disturbed ones. These achievements are important in restoring of native plant communities at set-aside fields

The potential of common ragweed for further spread: invasibility of different habitats and the role of disturbances and propagule pressure

The infilling of existing suitable habitats within a landscape after establishment is of critical importance for the final outcome of a plant invasion, yet it is an often overlooked process. Common ragweed, Ambrosia artemisiifolia, is an invasive annual species in Europe causing serious problems due to its highly allergenic pollen and as an agricultural weed. Recent studies have modelled the broad-scale distribution of the species and assessed future invasion risk, but for predicting the expected outcome of ragweed invasion we also need a mechanistic understanding of its local invasion success. We conducted a field experiment to investigate the invasibility of eight common non-arable habitat types and the role of soil disturbance in central Hungary, in the hot spot of ragweed invasion in Europe. Seed addition alone resulted in negligible amount of ragweed biomass, except for sites where disturbance was part of the present management. Soil disturbance alone resulted in ragweed at those few sites where ragweed seeds were present in the seed bank, related to farming in recent decades. When disturbance and seed addition were combined, ragweed emerged in all habitat types and reached high biomass in all habitat types except for closed forests. As our experiment showed that most habitat types have high invasibility when disturbed, we conclude that ragweed has a high potential for further spread, even in this heavily infested region. Management should focus on preventing seed dispersal and eradicating establishing populations where ragweed is still absent, while reducing soil disturbance may be needed to avoid ragweed emergence in infested sites. This latter may require a reconsideration of land-use practices in infested regions

„Tempus fugit, venit mors” – a streptococcalis toxikus sokk szindrómáról egy eset kapcsán = “Tempus fugit, venit mors” – about streptococcal toxic shock syndrome: a case report and mini-review

Absztrakt: A streptococcalis toxikus sokk szindróma hiperakut, életet veszélyeztető betegség, invazív (a leggyakrabban A-, kisebb arányban B-, G- és C-csoportú) Streptococcus-fertőzés szövődménye. A bevezető tünetek – láz, influenzára emlékeztető panaszok és a hipotenzió – szegényesek és aspecifikusak. A betegség gyors progressziója és rossz prognózisa miatt a diagnosztika feltétele a gyakran jellegtelen tünettanra (néha csupán láz és sokkállapot) támaszkodó korai klinikai gyanú. Az ellátás hárompillérű – antistreptococcalis terápia (és bizonyos esetekben intravénás immunglobulin) mellett a kórképhez társuló sokszervi elégtelenség intenzív szupportációja, valamint az infektív góc radikális sebészi megoldása elengedhetetlen. Közleményünkben infekciós góc nélküli (primer) S. pyogenes bacteriaemiához társuló streptococcalis toxikus sokk szindrómában meghalt betegünk esetét mutatjuk be, és összefoglaljuk a kórképpel kapcsolatos legfőbb irodalmi ismereteket. Orv Hetil. 2019; 160(48): 1887–1893. | Abstract: Streptococcal toxic shock syndrome (STSS) is a hyperacute, life-threatening illness, a complication of invasive streptococcal (mostly group A, rarely groups B, G or C) infection. There is no portal of entry (skin, vagina, pharynx) in nearly half of the STSS cases. The initial signs and symptoms (fever, flu-like complaints, hypotension) are scarce and aspecific, but because of its rapid progression and poor prognosis, early high level of suspicion is necessary. Management has 3 crucial points: initiation of anti-streptococcal regimen (and intravenous immunoglobulin in some cases), aggressive intensive care support of multi-organ failure, and surgical control of the infective source. In this article, we present a case of a patient succumbing to streptococcal toxic shock syndrome which was preceded by primary S. pyogenes bacteremia, and review the key points of this potentially fatal disease for practising clinicians. Orv Hetil. 2019; 160(48): 1887–1893

Composition and changes of blood microbiota in adult patients with community-acquired sepsis: A pilot study from bench to bedside

BackgroundCharacteristics of the blood microbiota among adult patients with community-acquired sepsis are poorly understood. Our aim was to analyze the composition of blood microbiota in adult patients with community-acquired sepsis, and correlate changes with non-septic control patients.MethodsA prospective observational study was carried out by including adult patients hospitalized for community-acquired sepsis at our center between January and November 2019, by random selection from a pool of eligible patients. Study inclusion was done on the day of sepsis diagnosis. Community acquisition was ascertained by a priori exclusion criteria; sepsis was defined according to the SEPSIS-3 definitions. Each included patient was matched with non-septic control patients by age and gender in a 1:1 fashion enrolled from the general population. Conventional culturing with BacT/ALERT system and 16S rRNA microbiota analysis were performed from blood samples taken in a same time from a patient. Abundance data was analyzed by the CosmosID HUB Microbiome software.ResultsAltogether, 13 hospitalized patients were included, 6/13 (46.2%) with sepsis and 7/13 (53.8%) with septic shock at diagnosis. The most prevalent etiopathogen isolated from blood cultures was Escherichia coli, patients mostly had intraabdominal septic source. At day 28, all-cause mortality was 15.4% (2/13). Compared to non-septic control patients, a relative scarcity of Faecalibacterium, Blautia, Coprococcus and Roseburia genera, with an abundance of Enhydrobacter, Pseudomonas and Micrococcus genera was observed among septic patients. Relative differences between septic vs. non-septic patients were more obvious at the phylum level, mainly driven by Firmicutes (25.7% vs. 63.1%; p<0.01) and Proteobacteria (36.9% vs. 16.6%; p<0.01). The alpha diversity, quantified by the Chao1 index showed statistically significant difference between septic vs. non-septic patients (126 ± 51 vs. 66 ± 26; p<0.01). The Bray-Curtis beta diversity, reported by principal coordinate analysis of total hit frequencies, revealed 2 potentially separate clusters among septic vs. non-septic patients.ConclusionIn adult patients with community-acquired sepsis, specific changes in the composition and abundance of blood microbiota could be detected by 16S rRNA metagenome sequencing, compared to non-septic control patients. Traditional blood culture results only partially correlate with microbiota test results

Maternal alterations in the proteome of the medial prefrontal cortex in rat

Proteomic differences between rat dams and control mothers deprived of their pups immediately after delivery were investigated in the medial prefrontal cortex (mPFC).A 2-D DIGE minimal dye technique combined with LC-MS/MS identified 32 different proteins that showed significant changes in expression in the mPFC, of which, 25 were upregulated and 7 were downregulated in dams. The identity of one significantly increased protein, the small heat-shock protein alpha-crystallin B chain (Cryab), was confirmed via Western blot analysis. Alpha-crystallin B chain was distributed in scattered cells in the mPFC, as demonstrated by immunohistochemistry. Furthermore, it was found to be localized in parvalbumin-containing neurons using double labeling. The elevation of its mRNA level in rat dams was also demonstrated via RT-PCR.The functional classification of the altered proteins was conducted using the UniProt and Gene Ontology protein databases. The identified proteins predominantly participate in synaptic transport and plasticity, neuron development, oxidative stress and apoptosis, and cytoskeleton organization. A common regulator and target analysis of these proteins determined using the Elsevier Pathway Studio Platform suggests that protein level changes associated with pup nursing are driven by growth factors and cytokines, while the MAP kinase pathway was identified as a common target. A high proportion of the proteins that were found to be altered in the mPFC are associated with depression. Biological significance: The behavior and emotional state of females change robustly when they become mothers. The brain, which governs these changes, may also undergo molecular alterations in mothers. As no proteomics approaches have been applied regarding maternal changes in the brain, we addressed this issue in the mPFC as this brain area is the uppermost cortical center of maternal control and the associated mood changes. The high number of protein-level alterations found between mothers taking care of their litter and those without pups indicates that pup nursing is associated with cortical protein-level changes. Alterations in proteins participating in synaptic transport, plasticity and neuron development suggest neuroplastic changes in the maternal brain. In turn, the relatively high number of altered proteins in the mPFC associated with depression suggests that the physiological effects of the protein-level alterations in the maternal mPFC could promote the incidence of postpartum depression. Cryab, a protein confirmed to be increased during maternal behaviors, was selectively found in parvalbumin cells, which, as fast-spiking interneurons, are associated with depression. The function of Cryab should be further investigated to establish whether it can be used to identify drug targets for future drug development. © 2016 Elsevier B.V

Long-term outcome of nitrogen immobilization to restore endemic sand grassland in Hungary

Soil nitrogen immobilization by carbon amendment is a management technique used for conservation purposes to increase the competitive ability of late-seral plant species over early-seral species based on their different tolerance of low soil nitrogen content. We immobilized nitrogen over six growing seasons on three ex-arable fields with poor sandy soils in the Hungarian lowland in order to restore endemic sandy grassland. Sucrose and sawdust were applied at rates based on previous laboratory experiments using local soils. We tested the efficacy of long-term carbon amendment for lowering soil nitrogen availability and favouring late-seral native species over early-seral weed species. Carbon amendments resulted in significant increase in soil microbial biomass C and reduced soil nitrogen availability after 2 years. Total vegetation cover was reduced by reducing soil nitrogen availability, but total species richness was not impacted. Cover of early-seral species decreased, and species richness and cover of late-seral species increased irrespective of nitrogen immobilization. However, after 4-6 years reducing soil nitrogen availability hampered the spread of moss under vascular vegetation. Synthesis and applications. This study supports the efficacy of carbon amendment as a tool to immobilize available soil nitrogen in the upper soil layers. However, the desired impact on vegetation was not fully achieved despite application over several years. Nitrogen immobilization was most relevant to bryophytes, lacking deep root systems, which may explain the responsiveness of this group to N limitation. The different impact of N availability on the complex of early-seral, late-seral vascular species and that of the bryophyte layer provides opportunity for directing state transformations in arid grasslands. Bryophyte cover can be suppressed through carbon amendments in order to enhance the germination and establishment of grassland species. The advantage of the method is that it opens bryophyte cover gradually without disturbing the soil surface, possibly avoiding the establishment of invasive species. However, further studies are required for deeper insight. © 2014 The Authors

Homokpusztagyepek természetvédelmi restaurációja a talaj-nitrogén immobilizációjával. 3. Mikrobiális biomassza C és N, ásványi N értékek alakulása a 2000–2002. évek között

Felhagyott homoki szántók természetes regenerációjának felgyorsítása érdekében különböző szénforrásokat alkalmaztunk a talaj-nitrogén mikrobiális immobilizációjának elősegítésére. Azt vizsgáltuk, hogy a kezelések hatással vannak-e a talajok mikrobiális biomasszájára és a talaj felvehető N-tartalmának alakulására. A Kiskunsági Nemzeti Park területén, Fülöpháza mellett egy felhagyott tanyán 3 területen (Bt = buckatető, Bk = buckaköz, R = rét) végeztük a kísérleteket. Szénforrás- ként kristálycukrot, valamint keményfa fűrészpor és faforgács keverékét alkalmaztuk többszöri ismétlésben a vegetációs időszakok alatt. A szénforrás-kezelések hatására a felvehető nitrogén, különösen a NO3⎯-N mennyisége szignifikánsan lecsökkent a talajban közvetlenül mérve és a kihelyezett ioncserélő műgyanta tesztekben egyaránt az R és Bk területen, a Bt területen csak az ioncserélő teszt mutatott szignifikáns kezeléshatást. A mikrobiális biomassza C és N az R és Bk területen szignifikánsan nagyobb lett a szénforrás-kezelés hatására, a Bt területen csak a mikrobiális C mutatott növekedést. A szénforrás-kezelések hatékonysága a különböző években és azon belül eltérő időszakokban változó volt. A mikrobiális biomassza áprilisban általában kisebb volt, mint májusban és szeptemberben. A talaj NO3⎯ -N-tartalma szeptemberben volt a legnagyobb. A cukor és fűrészpor együttes alkalmazásával a talaj felvehető N-tartalma, és a N-felvehetőség eredményesen csökkenthető , ami a természetvédelmi restauráció során a N-igényes gyomok visszaszorulását és a természetes gyepi fajok térnyerését segítheti elő, illetve felgyorsíthatja ezt a folyamatot