Molecular Investigation of the Fatal Bloodstream Candida orthopsilosis Infection Case following Gastrectomy.

Candida orthopsilosis represents a closely related cryptic genospecies of Candida parapsilosis complex-misidentified in routine diagnostic assays. This is emerging in settings where central venous catheters, invasive medical interventions, and echinocandin treatments are most likely to be used. A 59-year-old, non-neutropenic male patient, was admitted to an intensive care unit (ICU) due to respiratory distress syndrome, following a partial gastrectomy. As a result of duodenal stump leakage, re-laparotomy was required, abdominal drains were provided and central line catheters were exchanged. Multiple isolates of Candida orthopsilosis drawn from consecutive blood cultures were identified, despite ongoing echinocandin therapy and confirmed in vitro echinocandins susceptibility of the isolated strain. Species identification was verified via ITS region sequencing. Herein, we report the well-documented-per clinical data and relevant laboratory diagnosis-first case of a bloodstream infection caused by Candida orthopsilosis in Poland.

Data Science and Plant Metabolomics.

The study of plant metabolism is one of the most complex tasks, mainly due to the huge amount and structural diversity of metabolites, as well as the fact that they react to changes in the environment and ultimately influence each other. Metabolic profiling is most often carried out using tools that include mass spectrometry (MS), which is one of the most powerful analytical methods. All this means that even when analyzing a single sample, we can obtain thousands of data. Data science has the potential to revolutionize our understanding of plant metabolism. This review demonstrates that machine learning, network analysis, and statistical modeling are some techniques being used to analyze large quantities of complex data that provide insights into plant development, growth, and how they interact with their environment. These findings could be key to improving crop yields, developing new forms of plant biotechnology, and understanding the relationship between plants and microbes. It is also necessary to consider the constraints that come with data science such as quality and availability of data, model complexity, and the need for deep knowledge of the subject in order to achieve reliable outcomes.

Oxidative Status of Medicago truncatula Seedlings after Inoculation with Rhizobacteria of the Genus Pseudomonas, Paenibacillus and Sinorhizobium.

An increasing number of scientists working to raise agricultural productivity see the potential in the roots and the soil adjacent to them, together with a wealth of micro-organisms. The first mechanisms activated in the plant during any abiotic or biotic stress concern changes in the oxidative status of the plant. With this in mind, for the first time, an attempt was made to check whether the inoculation of seedlings of the model plant Medicago truncatula with rhizobacteria belonging to the genus Pseudomonas (P. brassicacearum KK5, P. corrugata KK7), Paenibacillus borealis KK4 and a symbiotic strain Sinorhizobium meliloti KK13 would change the oxidative status in the days following inoculation. Initially, an increase in H2O2 synthesis was observed, which led to an increase in the activity of antioxidant enzymes responsible for regulating hydrogen peroxide levels. The main enzyme involved in the reduction of H2O2 content in the roots was catalase. The observed changes indicate the possibility of using the applied rhizobacteria to induce processes related to plant resistance and thus to ensure protection against environmental stress factors. In the next stages, it seems reasonable to check whether the initial changes in the oxidative state affect the activation of other pathways related to plant immunity.

IoT in Water Quality Monitoring-Are We Really Here?

The Internet of Things (IoT) has become widespread. Mainly used in industry, it already penetrates into every sphere of private life. It is often associated with complex sensors and very complicated technology. IoT in life sciences has gained a lot of importance because it allows one to minimize the costs associated with field research, expeditions, and the transport of the many sensors necessary for physical and chemical measurements. In the literature, we can find many sensational ideas regarding the use of remote collection of environmental research. However, can we fully say that IoT is well established in the natural sciences?

Effects of Rhizosphere Bacteria on Strawberry Plants (Fragaria × ananassa Duch.) under Water Deficit.

Due to the observed climate warming, water deficiency in soil is currently one of the most important stressors limiting the size and quality of plant crops. Drought stress causes a number of morphological, physiological, and biochemical changes in plants, limiting their growth, development, and yield. Innovative methods of inducing resistance and protecting plants against stressors include the inoculation of crops with beneficial microorganisms isolated from the rhizosphere of the plant species to which they are to be applied. The aim of the present study was to evaluate 12 different strains of rhizosphere bacteria of the genera Pantoea, Bacillus, Azotobacter, and Pseudomonas by using them to inoculate strawberry plants and assessing their impact on mitigating the negative effects of drought stress. Bacterial populations were assessed by estimates of their size based on bacterial counts in the growth substrate and with bioassays for plant growth-promoting traits. The physiological condition of strawberry plants was determined based on the parameters of chlorophyll fluorescence. The usefulness of the test methods used to assess the influence of plant inoculation with rhizosphere bacteria on the response of plants growing under water deficit was also evaluated. A two-factor experiment was performed in a complete randomization design. The first experimental factor was the inoculation of plant roots with rhizosphere bacteria. The second experimental factor was the different moisture content of the growth substrate. The water potential was maintained at -10 to -15 kPa under control conditions, and at -40 to -45 kPa under the conditions of water deficit in the substrate. The tests on strawberry plants showed that the highest sensitivity to water deficiency, and thus the greatest usefulness for characterizing water stress, was demonstrated by the following indices of chlorophyll "a" fluorescence: FM, FV, FV/FM, PI, and Area. Based on the assessment of the condition of the photosynthetic apparatus and the analysis of chlorophyll "a" fluorescence indices, including hierarchical cluster analysis, the following strains of rhizosphere bacteria were found to have favorable effects on strawberry plants under water deficit: the Bacillus sp. strains DLGB2 and DKB26 and the Pantoea sp. strains DKB63, DKB70, DKB68, DKB64, and DKB65. In the tests, these strains of Bacillus sp. exhibited a common trait-the ability to produce siderophores, while those of Pantoea sp. were notable for phosphate mobilization and ACCD activity.

Bypassed ion-selective electrodes - self-powered polarization for tailoring of sensor performance.

Potentiometric ion-selective sensors are attractive analytical tools as they have simple apparatus and facile use; however their analytical parameters cannot be easily tuned. To tailor the performance of these sensors, application of instrumental control - electrochemical trigger - is usually required. The proposed approach offers a self-powered instrument-free alternative. It benefits from a spontaneous redox process for the ion-selective electrode bypassed by a zinc wire and a resistor connected in series. Spontaneous oxidation of zinc induces charge flow and the accompanying reduction of the solid contact material of the sensor, magnitude of the current and finally the potential of the electrode can be controlled by adjusting the bypass resistance. The ultimate result of the proposed approach is qualitatively equivalent to recording sensor response under polarized electrode potentiometry conditions, however, it does not require application of a galvanostat. The change in the magnitude of the resistance connected can be used to tailor analytical parameters such as detection limit, linear response range, and selectivity of the sensor. As a model example, potassium-selective all-solid-state sensors with a polypyrrole solid contact were used.

Induced ion-pair formation/ de-aggregation of rhodamine B octadecyl ester for anion optical sensing: Towards ibuprofen selective optical sensors.

A novel approach is explored to result in anion selective nanostructural optodes, that do not require the presence of selective ionophore. The sensing principle proposed is based on interactions of polarity sensitive dye with anions, leading to change of the chromophore group environment, resulting in increase of emission for increase of analyte concentration. To induce interactions of the analyte with the dye precise matching of properties of analyte and receptor is required. It is shown that the careful balancing of composition of nanostructural probes allows fine tuning of linear response range to cover lower concentration range. The model analyte studied was ibuprofen, due to its clinical and environmental relevance, lack of ionophore. As model probes rhodamine B octadecyl ester based nanostructures were prepared and applied. For optimized system turn-on responses were obtained for ibuprofen concentration change from 10-4.3 M to 10-2 M, with no effect of other anti-inflammatory drugs such as naproxen or salicylate.

Structural and Thermal Properties of Ethylene-Norbornene Copolymers Obtained Using Vanadium Homogeneous and SIL Catalysts.

The series of ethylene-norbornene (E-NB) copolymers was obtained using different vanadium homogeneous and supported ionic liquid (SIL) catalyst systems. The 13C and 1H NMR (carbon and proton nuclear magnetic resonance spectroscopy) together with differential scanning calorimetry (DSC) were applied to determine the composition of copolymers such as comonomer incorporation (CNB), monomer dispersity (MD), monomer reactivity ratio (re), sequence length of ethylene (le) and tetrad microblock distributions. The relation between the type of catalyst, reaction conditions and on the other hand, the copolymer microstructure, chain termination reaction analyzed by the type of unsaturation are discussed. In addition, the thermal properties of E-NB copolymers such as the melting and crystallization behavior, like also the heterogeneity of composition described by successive the self-nucleation and annealing (SSA) and the dispersity index (DI) were determined.

Ion-selective reversing aggregation-caused quenching - Maximizing optodes signal stability.

An alternative optical signal transduction mechanism for ion-selective optodes is proposed. The nanostructural sensors benefit from ion-selective reversing aggregation caused quenching yielding turn-on, bright and highly stable optical signals. Selective incorporation of analyte results in transformation of the polymer dye from aggregate to a micelle structure, affecting spatial arrangement of chromophore groups in the nanostructure. Formation of micelles, induced by ion-selective interactions, is coupled with pronounced increase of emission due to decrease of aggregation caused quenching, characteristic for dispersed phase formation. The formed micelles are highly stable in solution, offering constant in time (days scale) emission signal. The important difference from other known systems is that the analyte binding induced change does not affect the chromophore group, but occurs in distant, terminal position of the side chain of the polymer. As a model system calcium selective optodes have been prepared. Thus obtained probes were characterized with broad analyte concentration range (from 10-7 to 10-3 M) emission signal increase. The turn-on response was observed within broad range of pH (6.3-8.9), with no sign of optical signal deterioration during 5 days contact with the analyte or more than two weeks storage.

Quantifying plasticizer leakage from ion-selective membranes - a nanosponge approach.

The spontaneous process of release of plasticizers from membranes typically used in ion-selective sensors is an effect which limits the lifetime of sensors and comes with a risk of safety hazards. We use a nanosponge approach to look at the magnitude of this problem, quantifying the resulting contents of the plasticizer in solution. This novel method takes advantage of the spontaneous partition of the plasticizer (released and present in solution) into nanoparticles loaded with a solvatochromic dye. As a result, nanoparticles are transformed into capsules. This process is coupled with the turn-on fluorescence intensity change of the dye embedded in nanostructures, proportional to analyte concentration in the ppm range, providing insight into plasticizer contents in the solution. It was found that the spontaneous release of the plasticizer is dependent on its nature as well as the presence of an ionophore and ion-exchanger. For a typical ion-selective membrane composition the leakage effect results in up to 20 ppm of 2-nitrophenyl octyl ether found in solution after 12 h contact. On the other hand, for a less polar plasticizer - bis(2-ethylhexyl) sebacate, although the presence of an ionophore and ion-exchanger also increases the amount of the compound released from the membrane, its concentration in solution does not exceed 2 ppm after 12 h. The conclusions presented herein can be important not only for designing robust sensors but also for end-user safety. The results obtained for ion-selective membranes were equal within the range of experimental errors with those obtained using a liquid chromatography coupled with mass spectrometry (LC MS) approach, confirming the high analytical potential of the nanosponge approach.

2-(1,3-Oxazolin-2-yl)pyridine and 2,6-bis(1,3-oxazolin-2-yl) pyridine.

The data presented in this article are related to research articles "Titanium and vanadium catalysts with oxazoline ligands for ethylene-norbornene (co)polymerization (Ochedzan-Siodlak et al., 2018). For the title compounds, 2-(1,3-oxazolin-2-yl)pyridine (Py-ox) and 2,6-bis(1,3-oxazolin-2-yl)pyridine (Py-box), the single-crystal X-ray diffraction measurement together with NMR, GC, MS, DSC analysis, like also the method of crystallization are presented.

Critical assessment of polymeric nanostructures used as colorimetric ions probes.

In this study the effect of nature of nanostructural materials used as colorimetric optical probes on the analytical performance of the resulting sensors is compared. Different effects related to the nanoprobe materials - probe structure and properties: surface charge and stability, but also effects related to the analyte - receptor interactions - complex formation kinetics and transport of ions from the sample to the probe were taken into account. Presence of charge on the nanostructural colorimetric sensor effectively hinders ions exchange between the probe and the sample, leading to a linear dependence of absorbance on logarithm of analyte concentration changes. Interestingly, both anionic and cationic micelles are offering linear dependence on logarithm of concentration, covering 2 logarithmic units. Nanostructures, e.g. prepared from amphiphilic polymer Pluronic F127, lead to absorbance dependence on concentration observed in rather narrow concentration range. In this respect crosslinked poly(maleic anhydride-alt-1-octadecene) nanostructures of pH tunable surface charge, due to the presence of carboxyl and amine group on the surface, seem an attractive alternative, offering also the lowest detection limits among tested systems. This system is stable even in the presence of high concentration of background electrolyte in the sample and offers the lowest detection limit, what makes it useful as e.g. indicator for titration. Generally from the results obtained it follows that inert complexes, hindering ion transport to the probe, can be used to expose a linear dependence of the optical signal on logarithm of concentration, whereas for labile complexes formed sigmoidal type dependences of higher sensitivity over limited concentration range are obtained.

Nanoparticles of Fluorescent Conjugated Polymers: Novel Ion-Selective Optodes.

A novel type of ion-selective nano-optode is proposed, in which a conjugated polymer is used as optical transducer and nanoprobe material. Thus, contrary to most of the proposed optodes, the response does not require presence of pH-sensitive dye in the sensor. The conjugated polymer nanosensor material is in partially oxidized form-it is bearing positive charges and its emission is quenched. The receptor is an optically silent uncharged ionophore selective for the analyte cation. When a binding event occurs, positive charges are formed in the nanosphere, leading to a decrease in the oxidation state of the polymer, in the absence of redox potential change, resulting in increased emission. This general approach herein proposed results in a simple sensor, benefitting from a novel optical transduction mechanism and high lipophilicity of the polymer matrix that results in linear responses over a broad concentration range of analyte. For the model system studied, the linear dependence of emission intensity on the logarithm of analyte (K(+)) concentration was obtained for a broad range from 10(-5) M to 0.1 M.

Medicago truncatula Gaertn. as a model for understanding the mechanism of growth promotion by bacteria from rhizosphere and nodules of alfalfa.

MAIN CONCLUSION: The present study showed all the 16 strains isolated and identified from the alfalfa rhizosphere and nodules, and registered in GenBank, to be good candidates for targeted use in studies addressing the rather weak known mechanism of plant growth promotion, including that of Medicago truncatula, a molecular crop model. Based on physiological, biochemical and molecular analysis, the 16 isolates obtained were ascribed to the following five families: Bacillaceae, Rhizobiaceae, Xantomonadaceae, Enterobacteriaceae and Pseudomonadaceae, within which 9 genera and 16 species were identified. All these bacteria were found to significantly enhance fresh and dry weight of root, shoots and whole 5-week-old seedlings. The bacteria were capable of the in vitro use of tryptophan to produce indolic compounds at various concentrations. The ability of almost all the strains to enhance growth of seedlings and individual roots was positively correlated with the production of the indolic compounds (r = 0.69; P = 0.0001), but not with the 1-aminocyclopropane-1-carboxylate deaminase (ACCD) activity (no correlation). For some strains, it was difficult to conclude whether the growth promotion was related to the production of indolic compounds or to the ACCD activity. It is likely that promotion of M. truncatula root development involves also root interaction with pseudomonads, known to produce 2,4-diacetylphloroglucinol (DAPG), a secondary metabolite reported to alter the root architecture by interacting with an auxin-dependent signaling pathway. Inoculation of seedlings with Pseudomonas brassicacearum KK 5, a bacterium known for its lowest ability to produce indolic compounds, the highest ACCD activity and the presence of the phlD gene responsible for DAPG precursor synthesis, resulted in a substantial promotion of root development. Inoculation with the strain increased the endogenous IAA level in M. truncatula leaves after inoculation of 5-week-old seedlings. Three other strains examined in this study also increased the IAA level in the leaves upon inoculation. Moreover, several other factors such as mobilization of phosphorus and zinc to make them available to plants, iron sequestration by siderophore production and the ability to ammonia production also contributed substantially to the phytostimulatory biofertilizing potential of isolated strains. There is, thus, evidence that Medicago truncatula growth promotion by rhizobacteria involves more than one mechanism.

Optimizing calcium selective fluorimetric nanospheres.

Recently it was shown that optical nanosensors based on alternating polymers e.g. poly(maleic anhydride-alt-1-octadecene) were characterized by a linear dependence of emission intensity on logarithm of concentration over a few of orders of magnitude range. In this work we focus on the material used to prepare calcium selective nanosensors. It is shown that alternating polymer nanosensors offer competitive performance in the absence of calcium ionophore, due to interaction of the nanospheres building blocks with analyte ions. The emission increase corresponds to increase of calcium ions contents in the sample within the range from 10(-4) to 10(-1) M. Further improvement in sensitivity (from 10(-6) to 10(-1) M) and selectivity can be achieved by incorporating calcium ionophore in the nanospheres. The optimal results were obtained for core-shell nanospheres, where the core was prepared from poly(styrene-co-maleic anhydride) and the outer layer from poly(maleic anhydride-alt-1-octadecene). Thus obtained chemosensors were showing linear dependence of emission on logarithm of calcium ions concentration within the range from 10(-7) to 10(-1) M.

Alternating polymer micelle nanospheres for optical sensing.

A novel concept of nanosized fluorimetric sensors is proposed, using alternating polymers as self assembling micelles that can be crosslinked resulting in stable polymeric nanoparticles. The thus obtained nanospheres have sizes close to 250 nm or 130 nm, depending on the preparation procedure and the negative surface charge, due to the presence of carboxyl groups on the surface. By a simple procedure, the nanospheres can be effectively loaded with compounds of choice, e.g. ionophores and ion-exchangers previously used to induce ionic sensitivity in polyacrylate or poly(vinyl chloride) micro- and nanospheres (miniature optrodes), thus allowing for optical or fluorimetric quantification of analytes. As a proof of concept, H(+) sensitive colorimetric and fluorimetric sensors and K(+) fluorimetric sensors using classical optrode approach were prepared and tested. The obtained sensors were characterized by high sensitivity, fast and reversible responses. Both K(+) and H(+) sensors were characterized by a broad response range resulting from the significant effect of processes occurring on the surface of the nanospheres. Due to this effect, the fluorimetric responses of the obtained spheres are significantly different from those typically observed for miniature optrode systems, and were linear within a range of at least 5 logarithmic units of analyte concentration. As shown, the surface groups of the herein proposed nanospheres can be used for the covalent linking of fluorophores that can be used as markers (if applied alone) or as reference dyes for fluorescent ion-sensitive nanospheres.

Hydrocephalus in newborns: clinical conditions and primary surgical treatment.

BACKGROUND: Hydrocephalus is a state in which excessive accumulation of cerebrospinal fluid occurs in intracranial space as a result of disorders of its circulation hydrodynamics. OBJECTIVES: The aim of this study was to analyze the clinical conditions and primary surgical treatment of hydrocephalus in the newborns examined in the study. MATERIAL AND METHODS: The data was gathered using a retrospective analysis of the medical and nursing records of 57 newborns treated for hydrocephalus at the Department of Pediatric Surgery of the Dr. A. Jurasz University Hospital in Bydgoszcz, Poland. RESULTS: In the years 2008-2009 at the Department of Pediatric Surgery of Dr. A. Jurasz University Hospital in Bydgoszcz, 57 newborns were treated for hydrocephalus. In all patients (100% of the study group) regardless of sex, age, place of residence or etiology, the doctors used surgical therapy. CONCLUSIONS: There is a connection between selected causes of hydrocephalus in the study group and sociodemographic characteristics such as the place of residence or age. Sociodemographic data (sex, age, place of residence) have no effect on the treatment of hydrocephalus in newborns. In all cases of hydrocephalus in the study, the treatment used was implantation of a drainage system. Rickham reservoirs are more rarely implanted in full-term newborns than in premature ones, while ventricle-peritoneal valves are more frequently used in full-term newborns than in premature babies. Regardless of the reason for hydrocephalus formation, the treatment is based on surgical intervention and the most common drainage system used to correct the defect is the ventricle-peritoneal valve.

Microspheres aided introduction of ionophore and ion-exchanger to the ion-selective membrane.

In this work a novel method for introduction of ionophore and ion-exchanger to the ion-selective polyacrylate based membrane is proposed. These compounds (and optionally primary ions) are introduced to polyacrylate microspheres, used to prepare ion-selective membrane. The approach proposed here can be used to prepare membranes containing primary ions equally distributed through the receptor phase, i.e. membranes that do not require conditioning in primary ions solution and are free from problems related to slow diffusion of primary ions. Thus obtained sensors were characterized with linear responses (also at relatively high activities) and high selectivities, despite considerable reduction of ionophore and ion-exchanger amount introduced to the membrane. To be able to prepare ion-selective membranes using this approach, a method for quantification of ionophore and ion-exchanger introduced into microspheres is required. In this work a novel method utilizing high performance liquid chromatography (HPLC) with DAD or FLD detection is proposed. Incorporation of ionophore and ion-exchanger into the microspheres was achieved either by absorption into ready spheres or in course of photopolymerization of polymeric beads. The obtained results have proven that both procedures led to incorporation of ionophore/ion-exchanger into polymeric spheres, however, the content of the compounds in the spheres post process is different from their ratio in solution from which they had been introduced. These effects need to be considered/compensated while preparing microspheres containing ion-selective membranes. As a model system poly(n-butyl acrylate) spheres, silver selective ionophore and sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate were chosen, resulting ultimately in silver-selective electrodes.

Photopolymerized polypyrrole microvessels.

We report on the preparation of water-filled polymer microvessels through the photopolymerization of pyrrole in a water/chloroform emulsion. The resulting structures were characterized by complementary spectroscopic and microscopic techniques, including Raman spectroscopy, XPS, SEM, and TEM. The encapsulation of fluorescent, magnetic, and ionic species within the microvessels has been demonstrated. Confocal microscopy and fluorescence anisotropy measurements revealed that the encapsulated chromophore (Rhodamine 6G) resides within voids in the capsules; however, strong interaction of the dye with polypyrrole results in a measurable decrease in its rotational dynamics. Microvessels loaded with ferrofluid exhibit magnetic properties, and their structures can be directed with an external magnetic field. TEM measurements allowed imaging of individual nanoparticles entrapped within the vessels. The application of Cu(2+)-loaded microvessels as a transducer layer in all-solid-state ion-selective electrodes was also demonstrated.

Gold nanoparticles solid contact for ion-selective electrodes of highly stable potential readings.

Internal solution free ion-selective electrodes were prepared applying for the first time gold nanoparticles as a solid contact layer. The presence of a layer of gold nanoparticles stabilized with aliphatic thiols at the back side of the membrane resulted in highly stable potentiometric responses of the sensors, good selectivities and close to Nernstian slopes. Electrochemical studies have confirmed that the applied material is effectively working as capacitive solid contact, yielding high stability sensors.