Multifaceted Assessment of Porous Silica Nanocomposites: Unraveling Physical, Structural, and Biological Transformations Induced by Microwave Field Modification

In response to the persistent challenge of heavy and noble metal environmental contamination, our research explores a new idea to capture silver through porous spherical silica nanostructures. The aim was realized using microwave radiation at varying power (P = 150 or 800 W) and exposure times (t = 60 or 150 s). It led to the development of a silica surface with enhanced metal-capture capacity. The microwave-assisted silica surface modification influences the notable changes within the carrier but also enforces the crystallization process of silver nanoparticles with different morphology, structure, and chemical composition. Microwave treatment can also stimulate the formation of core-shell bioactive Ag/Ag2CO3 heterojunctions. Due to the silver nanoparticles' sphericity and silver carbonate's presence, the modified nanocomposites exhibited heightened toxicity against common microorganisms, such as E. coli and S. epidermidis. Toxicological assessments, including minimum inhibitory concentration (MIC) and half-maximal inhibitory concentration (IC50) determinations, underscored the efficacy of the nanocomposites. This research represents a significant stride in addressing pollution challenges. It shows the potential of microwave-modified silicas in the fight against environmental contamination. Microwave engineering underscores a sophisticated approach to pollution remediation and emphasizes the pivotal role of nanotechnology in shaping sustainable solutions for environmental stewardship.

Functionalization of the NiTi Shape Memory Alloy Surface through Innovative Hydroxyapatite/Ag-TiO2 Hybrid Coatings

The objective of this research was to develop a surface modification for the NiTi shape memory alloy, thereby enabling its long-term application in implant medicine. This was achieved through the creation of innovative multifunctional hybrid layers comprising a nanometric molecular system of silver-rutile (Ag-TiO2), known for its antibacterial properties, in conjunction with bioactive submicro- and nanosized hydroxyapatite (HAp). The multifunctional, continuous, crack-free coatings were produced using the electrophoretic deposition method (EPD) at 20 V/1 min. Structural and morphological analyses through Raman spectrometry and scanning electron microscopy (SEM) provided comprehensive insights into the obtained coating. The silver within the layer existed in the form of nanometric silver carbonates (Ag2CO3) and metallic nanosilver. Based on DTA/TG results, dilatometric measurements, and high-temperature microscopy, the heat treatment temperature for the deposited layers was set at 800 °C for 2 h. The procedures applied resulted in the creation of a new generation of materials with a distinct structure compared with the initial nanopowders. The resulting composite layer, measuring 2 μm in thickness, comprised hydroxyapatite (HAp), apatite carbonate (CHAp), metallic silver, silver oxides, Ag@C, and rutile exhibiting a defective structure. This structural characteristic contributes significantly to its heightened activity, influencing both bioactivity and biocompatibility properties.

The genomic response to urbanization in the damselfly Ischnura elegans

The complex and rapid environmental changes brought about by urbanization pose significant challenges to organisms. The multifaceted effects of urbanization often make it difficult to define and pinpoint the very nature of adaptive urban phenotypes. In such situations, scanning genomes for regions differentiated between urban and non-urban populations may be an attractive approach. Here, we investigated the genomic signatures of adaptation to urbanization in the damselfly Ischnura elegans sampled from 31 rural and urban localities in three geographic regions: southern and northern Poland, and southern Sweden. Genome-wide variation was assessed using more than 370,000 single nucleotide polymorphisms (SNPs) genotyped by ddRADseq. Associations between SNPs and the level of urbanization were tested using two genetic environment association methods: Latent Factors Mixed Models and BayPass. While we found numerous candidate SNPs and a highly significant overlap between candidates identified by the two methods within the geographic regions, there was a distinctive lack of repeatability between the geographic regions both at the level of individual SNPs and of genomic regions. However, we found "synapse organization" at the top of the functional categories enriched among the genes located in the proximity of the candidate urbanization SNPs. Interestingly, the overall significance of "synapse organization" was built up by the accretion of different genes associated with candidate SNPs in different geographic regions. This finding is consistent with the highly polygenic nature of adaptation, where the response may be achieved through a subtle adjustment of allele frequencies in different genes that contribute to adaptive phenotypes. Taken together, our results point to a polygenic adaptive response in the nervous system, specifically implicating genes involved in synapse organization, which mirrors the findings from several genomic and behavioral studies of adaptation to urbanization in other taxa.

NiTi Shape Memory Clamps with Modified Surface for Bone Fracture Treatment

Using NiTi alloys with shape memory for long-term medical implants requires modification of their surface due to the possible occurrence of corrosion. Hence, the surface of the staples used to join fractured bone within the craniofacial region was modified by applying a titanium oxy-nitrogen layer and a hydroxyapatite coating. Surface-modified clamps were tested in vivo using New Zealand white rabbits. After determining the mechanical characteristics of the bone and considering the initial state and surface modification, the diameter of the wire (used to make the clamps with the appropriate compression force) was selected. Implantation was performed on two groups of rabbits: experimental and control. In the experimental group, an intentionally induced bone fracture was treated in one tibia. On the second tibia, two additional clamps were applied to increase the possibility of a negative impact of the NiTi alloy on a living organism. After 6 weeks of application, a proper joining of the broken bone fragments was stated. Whereas after twelve weeks, no negative impact of the clamp material on a living organism, i.e., a rabbit, was found. Hence, the clamp with the modified surface can connect bone fragments in humans as well as small and medium-sized animals, with an extended range of use up to 12 weeks.

Biological Activity and Thrombogenic Properties of Oxide Nanotubes on the Ti-13Nb-13Zr Biomedical Alloy

The success of implant treatment is dependent on the osseointegration of the implant. The main goal of this work was to improve the biofunctionality of the Ti-13Nb-13Zr implant alloy by the production of oxide nanotubes (ONTs) layers for better anchoring in the bone and use as an intelligent carrier in drug delivery systems. Anodization of the Ti-13Nb-13Zr alloy was carried out in 0.5% HF, 1 M (NH₄)₂SO₄ + 2% NH₄F, and 1 M ethylene glycol + 4 wt.% NH₄F electrolytes. Physicochemical characteristics of ONTs were performed by high-resolution electron microscopy (HREM), X-ray photoelectron spectroscopy (XPS), and scanning Kelvin probe (SKP). Water contact angle studies were conducted using the sitting airdrop method. In vitro biological properties and release kinetics of ibuprofen were investigated. The results of TEM and XPS studies confirmed the formation of the single-walled ONTs of three generations on the bi-phase (α + β) Ti-13Nb-13Zr alloy. The ONTs were composed of oxides of the alloying elements. The proposed surface modification method ensured good hemolytic properties, no cytotoxity for L-929 mouse cells, good adhesion, increased surface wettability, and improved athrombogenic properties of the Ti-13Nb-13Zr alloy. Nanotubular surfaces allowed ibuprofen to be released from the polymer matrix according to the Gallagher-Corrigan model.

Microwave Irradiation vs. Structural, Physicochemical, and Biological Features of Porous Environmentally Active Silver–Silica Nanocomposites

Heavy metals and other organic pollutants burden the environment, and their removal or neutralization is still inadequate. The great potential for development in this area includes porous, spherical silica nanostructures with a well-developed active surface and open porosity. In this context, we modified the surface of silica spheres using a microwave field (variable power and exposure time) to increase the metal uptake potential and build stable bioactive Ag2O/Ag2CO3 heterojunctions. The results showed that the power of the microwave field (P = 150 or 700 W) had a more negligible effect on carrier modification than time (t = 60 or 150 s). The surface-activated and silver-loaded silica carrier features like morphology, structure, and chemical composition correlate with microbial and antioxidant enzyme activity. We demonstrated that the increased sphericity of silver nanoparticles enormously increased toxicity against E. coli, B. cereus, and S. epidermidis. Furthermore, such structures negatively affected the antioxidant defense system of E. coli, B. cereus, and S. epidermidis through the induction of oxidative stress, leading to cell death. The most robust effects were found for nanocomposites in which the carrier was treated for an extended period in a microwave field.

Functionalization of the Implant Surface Made of NiTi Shape Memory Alloy

To functionalize and improve the biocompatibility of the surface of a medical implant made of NiTi shape memory alloy and used in practice, a clamp, multifunctional layers composed of amorphous TiO₂ interlayer, and a hydroxyapatite coating were produced. Electrophoresis, as an efficient method of surface modification, resulted in the formation of a uniform coating under a voltage of 60 V and deposition time of 30 s over the entire volume of the implant. The applied heat treatment (800 °C/2 h) let toa dense, crack-free, well-adhered HAp coating with a thickness of ca. 1.5 μm. and a high crack resistance to deformation associated with the induction of the shape memory effect in the in the deformation range similar to the real implant work after implantation. Moreover, the obtained coating featured a hydrophilic (CA = 59.4 ± 0.3°) and high biocompatibility.

In Vitro Bioelectrochemical Properties of Second-Generation Oxide Nanotubes on Ti-13Zr-13Nb Biomedical Alloy

Surface charge and in vitro corrosion resistance are some of the key parameters characterizing biomaterials in the interaction of the implant with the biological environment. Hence, this work investigates the in vitro bioelectrochemical behavior of newly developed oxide nanotubes (ONTs) layers of second-generation (2G) on a Ti-13Zr-13Nb alloy. The 2G ONTs were produced by anodization in 1 M (NH₄)₂SO₄ solution with 2 wt.% of NH₄F. The physical and chemical properties of the obtained bamboo-inspired 2G ONTs were characterized using scanning electron microscopy with field emission and energy dispersive spectroscopy. Zeta potential measurements for the examined materials were carried out using an electrokinetic analyzer in aqueous electrolytes of potassium chloride, phosphate-buffered saline and artificial blood. It was found that the electrolyte type and the ionic strength affect the bioelectrochemical properties of 2G ONTs layers. Open circuit potential and anodic polarization curve results proved the influence of anodizing on the improvement of in vitro corrosion resistance of the Ti-13Zr-13Nb alloy in PBS solution. The anodizing conditions used can be proposed for the production of long-term implants, which are not susceptible to pitting corrosion up to 9.4 V.

Influence of Anodizing Conditions on Biotribological and Micromechanical Properties of Ti-13Zr-13Nb Alloy

The biomedical Ti-13Zr-13Nb bi-phase (α + β) alloy for long-term applications in implantology has recently been developed. The porous oxide nanotubes' (ONTs) layers of various geometries and lengths on the Ti-13Zr-13Nb alloy surface can be produced by anodizing to improve osseointegration. This work was aimed at how anodizing conditions determinatine the micromechanical and biotribological properties of the Ti-13Zr-13Nb alloy. First-generation (1G), second-generation (2G), and third-generation (3G) ONT layers were produced on the Ti-13Zr-13Nb alloy surface by anodizing. The microstructure was characterized using SEM. Micromechanical properties were investigated by the Vickers microhardness test under variable loads. Biotribological properties were examined in Ringer's solution in a reciprocating motion in the ball-on-flat system. The 2D roughness profiles method was used to assess the wear tracks of the tested materials. Wear scars' analysis of the ZrO₂ ball was performed using optical microscopy. It was found that the composition of the electrolyte with the presence of fluoride ions was an essential factor influencing the micromechanical and biotribological properties of the obtained ONT layers. The three-body abrasion wear mechanism was proposed to explain the biotribological wear in Ringer's solution for the Ti-13Zr-13Nb alloy before and after anodizing.

POS1529-HPR SEXUAL DYSFUNCTION AND QUALITY OF LIFE IN PATIENTS WITH RHEUMATOID ARTHRITIS

Background

Sexual health is a major component of human well-being. The World Health Organization (WHO) defines sexual health as “a state of physical, mental, emotional, and social well-being in relation to sexuality”. Sexuality is a very important, inherent part of human functioning. As repeatedly shown in research, satisfaction with sex life and sexual fulfillment correlate positively with quality of life (QoL) in most of its aspects. It is thus true that a reduced quality of one’s sex life and lack of sexual fulfillment can contribute to poorer QoL overall. As poor sex life quality and sexual dissatisfaction result from sexual dysfunction, effective treatment of such a dysfunction can be assumed to contribute significantly to a better QoL.

Objectives

To describe an assessment of sexual problem among RA patients as a part of patient-reported outcome measures assessment.

Methods

171 consecutive RA patients (mean age 48.3±14.6) attending the rheumatology outpatients clinic over 6 months in 2021. Standardized questionnaires were used in the study: The Sexological Questionnaire to assess self-assessment of the incidence of sexual disorders, WHOQOL-BREF to assess QoL level, Disease Acceptance Scale and VAS scale to assess pain intensity.

Results

The mean duration of the disease in the study group was 13±9 years. The mean score of subjective assessment of mobility was 6.2 ± 1.6, and the mean score of the DAS-28 disease activity index was 4.0±1.9. The study group presented a mean level of disease acceptance (AIS 29.6 ± 11.6). The comparative analysis showed significant differences in reaching orgasm and declared sexual dysfunctions. These problems occurred more often in women than in men (34.2% vs. 18% and 43% vs. 40% respectively p=0.002). In univariate analysis, factors correlating positively with the frequency of declaring sexual dysfunction were: subjective motor score less than 6 points, AIS<36 points, WHOQOL-BREF<59 points, disease activity ≥3.5 points and VAS>3. In multivariate logistic regression analysis independent factors positively correlating with frequency of sexual dysfunction declaration were: general QoL (β=1.255; p=0.035) and pain limiting social life (β=1.564; p=0.030). The absence of comorbidities correlated negatively and reduced the prevalence of sexual dysfunction (β=-1.030, p=0.043). Patients with reduced QoL had 3.5 times and patients with pain limiting social life had 4.8 times higher risk of sexual dysfunction than other patients. In contrast, those without comorbidities were 2.8 times more likely to be free of sexual dysfunction than those diagnosed with other chronic diseases besides RA.

Conclusion

Sexual dysfunction is a problem found both in women and in men with RA. The most common problems include lack of orgasm, vaginal dryness in women, and erectile dysfunction in men. Psychological factors that contribute to sexual dysfunction include low or no illness acceptance and poor QoL. The absence of comorbidities is an independent determinant of lower sexual dysfunction incidence, whereas low QoL and pain limiting the patient’s social life are independent determinants of increased incidence of sexual dysfunction in both sexes.

References

[1]Hunter TM, Boytsov NN, Zhang X, et al. Prevalence of rheumatoid arthritis in the United States adult population in healthcare claims databases, 2004-2014. Rheumatol Int. 2017;37:1551.

[2]Tristano AG. Impact of rheumatoid arthritis on sexual function. World J Orthop. 2014;5(2):107-11.

[3]WHO. Sexual and Reproductive Health and Research (SRH). Definition. URL: https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&cad=rja&uact=8&ved=2ahUKEwjS3fS6gZr1AhXS66QKHbGwDHkQFnoECAwQAQ&url=https%3A%2F%2Fwww.euro.who.int%2Fen%2Fhealth-topics%2FLife-stages%2Fsexual-and-reproductive-health%2Fnews%2Fnews%2F2011%2F06%2Fsexual-health-throughout-life%2Fdefinition&usg=AOvVaw20satnO_o687QKq2N8ELi0 [Accessed: 05.01.2022].

[4]Oettingen J. Sexual dysfunction – approach based on cognitive theory. Polish sexology 2013;11(2):68-75.

Disclosure of Interests

None declared

The impact of sleep disorders on the daily activity and quality of life in rheumatoid arthritis patients - a systematic review and meta-analysis

OBJECTIVE

We aimed at determining the relationship between sleep disorders and daily activity and quality of life (QoL) of patients with rheumatoid arthritis (RA).

MATERIALS AND METHODS

A systematic search of databases was carried out. We used the Cochrane guidelines to perform the meta-analysis following the PRISMA statement. Fifteen full-text papers were ultimately included in the subsequent statistical analyses. The study was registered in the PROSPERO database (No. CRD42021245664).

RESULTS

In group 1, the mean sleep quality score measured with the Pittsburgh Sleep Quality Index (PSQI) was 6.93. The mean QoL score for the physical domain and the mental domain of the Short Form (36) Health Survey (SF-36) was 38.15 and 41.83, respectively. In group 2, the mean PSQI score was 7.21. The mean daily activity score measured with the Health Assessment Questionnaire (HAQ) was 0.80. A strong negative correlation was observed between the PSQI scores, and the SF-36 total score each unit increase in the SF-36 total score was associated with an average decrease of 0.35 points in the PSQI score. A one-point increase in the PSQI score was associated with an average decrease of 2.4 points in the QoL score measured with SF-36.

CONCLUSIONS

RA patients have a low quality of sleep. Sleep disorders correlate negatively with the QoL scores in the physical and mental domains.

Production and Characterization of the Third-Generation Oxide Nanotubes on Ti-13Zr-13Nb Alloy

In the group of vanadium-free titanium alloys used for applications for long-term implants, the Ti-13Zr-13Nb alloy has recently been proposed. The production of a porous layer of oxide nanotubes (ONTs) with a wide range of geometries and lengths on the Ti-13Zr-13Nb alloy surface can increase its osteoinductive properties and enable intelligent drug delivery. This work concerns developing a method of electrochemical modification of the Ti-13Zr-13Nb alloy surface to obtain third-generation ONTs. The effect of the anodizing voltage on the microstructure and thickness of the obtained oxide layers was conducted in 1 M C₂H₆O₂ + 4 wt% NH₄F electrolyte in the voltage range 5–35 V for 120 min at room temperature. The obtained third-generation ONTs were characterized using SEM, EDS, SKP, and 2D roughness profiles methods. The preliminary assessment of corrosion resistance carried out in accelerated corrosion tests in the artificial atmosphere showed the high quality of the newly developed ONTs and the slight influence of neutral salt spray on their micromechanical properties.

Relationship between maximum eye temperature and plasma cortisol concentration in racehorses during intensive training

The aim of the study was to determine the utility of maximum eye temperature measured by infrared thermography (IRT) as a stress indicator compared with plasma cortisol concentration in Thoroughbred and Arabian racehorses. The study included thirty racehorses undergoing standard training for racing. Measurements of maximum eye temperature and blood collection for plasma cortisol concentration were carried out before training (BT), and within 5 (5AT) and 120 minutes (120AT) after the end of the each training session in three repetitions, with a monthly interval. Both parameters were elevated at 5AT compared to BT (p⟨0.001). Compared to BT, at 120AT the maximum eye temperature remained elevated (p⟨0.001) and plasma cortisol concentration decreased (p⟨0.001). The study indicated significant weak correlations (r=0.220; p⟨0.001) between both measurements at all time points. The results support the use of IRT technique to monitor the response of horses to stress, potentially improving animal management and welfare.

Production, Characterization and Application of Oxide Nanotubes on Ti-6Al-7Nb Alloy as a Potential Drug Carrier

This work concerns the development of a method of functionalization of the surface of the biomedical Ti–6Al–7Nb alloy by producing oxide nanotubes (ONTs) with drug-eluting properties. Shaping of the morphology, microstructure, and thickness of the oxide layer was carried out by anodization in an aqueous solution of 1 M ethylene glycol with the addition of 0.2 M NH₄F in the voltage range 5–100 V for 15–60 min at room temperature. The characterization of the physicochemical properties of the obtained ONTs was performed using SEM, XPS, and EDAX methods. ONTs have been shown to be composed mainly of TiO₂, Al₂O₃, and Nb₂O₅. Single-walled ONTs with the largest specific surface area of 600 cm² cm⁻² can be obtained by anodization at 50 V for 60 min. The mechanism of ONT formation on the Ti–6Al–7Nb alloy was studied in detail. Gentamicin sulfate loaded into ONTs was studied using FTIR, TG, DTA, and DTG methods. Drug release kinetics was determined by UV–Vis spectrophotometry. The obtained ONTs can be proposed for use in modern implantology as carriers for drugs delivered locally in inflammatory conditions.

Coevolution between MHC class I and Antigen Processing Genes in salamanders

Proteins encoded by antigen-processing genes (APGs) provide major histocompatibility complex (MHC) class I (MHC-I) with antigenic peptides. In mammals, polymorphic multigenic MHC-I family is served by monomorphic APGs, whereas in certain nonmammalian species both MHC-I and APGs are polymorphic and coevolve within stable haplotypes. Coevolution was suggested as an ancestral gnathostome feature, presumably enabling only a single highly expressed classical MHC-I gene. In this view coevolution, while optimizing some aspects of adaptive immunity, would also limit its flexibility by preventing the expansion of classical MHC-I into a multigene family. However, some nonmammalian taxa, such as salamanders, have multiple highly expressed MHC-I genes, suggesting either that coevolution is relaxed or that it does not prevent the establishment of multigene MHC-I. To distinguish between these two alternatives, we use salamanders (30 species from 16 genera representing six families) to test, within a comparative framework, a major prediction of the coevolution hypothesis: the positive correlation between MHC-I and APG diversity. We found that MHC-I diversity explained both within-individual and species-wide diversity of two APGs, TAP1 and TAP2, supporting their coevolution with MHC-I, whereas no consistent effect was detected for the other three APGs (PSMB8, PSMB9, and TAPBP). Our results imply that although coevolution occurs in salamanders, it does not preclude the expansion of the MHC-I gene family. Contrary to the previous suggestions, nonmammalian vertebrates thus may be able to accommodate diverse selection pressures with flexibility granted by rapid expansion or contraction of the MHC-I family, while retaining the benefits of coevolution between MHC-I and TAPs.

Key Properties of a Bioactive Ag-SiO2/TiO2 Coating on NiTi Shape Memory Alloy as Necessary at the Development of a New Class of Biomedical Materials

Recent years have seen the dynamic development of methods for functionalizing the surface of implants using biomaterials that can mimic the physical and mechanical nature of native tissue, prevent the formation of bacterial biofilm, promote osteoconduction, and have the ability to sustain cell proliferation. One of the concepts for achieving this goal, which is presented in this work, is to functionalize the surface of NiTi shape memory alloy by an atypical glass-like nanocomposite that consists of SiO2-TiO2 with silver nanoparticles. However, determining the potential medical uses of bio(nano)coating prepared in this way requires an analysis of its surface roughness, tribology, or wettability, especially in the context of the commonly used reference coat-forming hydroxyapatite (HAp). According to our results, the surface roughness ranged between (112 ± 3) nm (Ag-SiO2)-(141 ± 5) nm (HAp), the water contact angle was in the range (74.8 ± 1.6)° (Ag-SiO2)-(70.6 ± 1.2)° (HAp), while the surface free energy was in the range of 45.4 mJ/m2 (Ag-SiO2)-46.8 mJ/m2 (HAp). The adhesive force and friction coefficient were determined to be 1.04 (Ag-SiO2)-1.14 (HAp) and 0.247 ± 0.012 (Ag-SiO2) and 0.397 ± 0.034 (HAp), respectively. The chemical data showed that the release of the metal, mainly Ni from the covered NiTi substrate or Ag from Ag-SiO2 coating had a negligible effect. It was revealed that the NiTi alloy that was coated with Ag-SiO2 did not favor the formation of E. coli or S. aureus biofilm compared to the HAp-coated alloy. Moreover, both approaches to surface functionalization indicated good viability of the normal human dermal fibroblast and osteoblast cells and confirmed the high osteoconductive features of the biomaterial. The similarities of both types of coat-forming materials indicate an excellent potential of the silver-silica composite as a new material for the functionalization of the surface of a biomaterial and the development of a new type of functionalized implants.

Innovative Bioactive Ag-SiO2/TiO2 Coating on a NiTi-Shape Memory Alloy: Structure and Mechanism of Its Formation

In recent years, more and more emphasis has been placed on the development and functionalization of metallic substrates for medical applications to improve their properties and increase their applicability. Today, there are many different types of approaches and materials that are used for this purpose. Our idea was based on a combination of a chemically synthesized Ag-SiO2 nanocomposite and the electrophoretic deposition approach on a NiTi-shape memory substrate. As a result, silver-silica coating was developed on a previously passivated alloy, which was then subjected to sintering at 700 °C for 2 h. The micrometer-sized coat-forming material was composed of large agglomerates consisting of silica and a thin film of submicron- and nano- spherical-shaped particles built of silver, carbon, and oxygen. Structurally, the coatings consisted of a combination of nanometer-sized silver-carbonate that was embedded in thin amorphous silica and siloxy network. The temperature impact had forced morphological and structural changes such as the consolidation of the coat-forming material, and the partial coalescence of the silver and silica particles. As a result, a new continuous complex ceramic coating was formed and was analyzed in more detail using the XPS, XRD, and Raman methods. According to the structural and chemical analyses, the deposited Ag-SiO2 nanocomposite material's reorganization was due to its reaction with a passivated TiO2 layer, which formed an atypical glass-like composite that consisted of SiO2-TiO2 with silver particles that stabilized the network. Finally, the functionalization of the NiTi surface did not block the shape memory effect.

An Organic-Inorganic Hybrid Nanocomposite as a Potential New Biological Agent

To solve the problem of human diseases caused by a combination of genetic and environmental factors or by microorganisms, intense research to find completely new materials is required. One of the promising systems in this area is the silver-silica nanocomposites and their derivatives. Hence, silver and silver oxide nanoparticles that were homogeneously distributed within a silica carrier were fabricated. Their average size was d = (7.8 ± 0.3) nm. The organic polymers (carboxymethylcellulose (CMC) and sodium alginate (AS)) were added to improve the biological features of the nanocomposite. The first system was prepared as a silver chlorine salt combination that was immersed on a silica carrier with coagulated particles whose size was d = (44.1 ± 2.3) nm, which coexisted with metallic silver. The second system obtained was synergistically interacted metallic and oxidized silver nanoparticles that were distributed on a structurally defective silica network. Their average size was d = (6.6 ± 0.7) nm. Physicochemical and biological experiments showed that the tiny silver nanoparticles in Ag/SiO₂ and Ag/SiO₂@AS inhibited E. coli, P. aeruginosa, S. aureus, and L. plantarum's cell growth as well as caused a high anticancer effect. On the other hand, the massive silver nanoparticles of Ag/SiO₂@CMC had a weaker antimicrobial effect, although they highly interacted against PANC-1. They also generated reactive oxygen species (ROS) as well as the induction of apoptosis via the p53-independent mechanism.

Functionalization of the NiTi Shape Memory Alloy Surface by HAp/SiO2/Ag Hybrid Coatings Formed on SiO2-TiO2 Glass Interlayer

The surface modification of NiTi shape memory alloys is a method for increasing their multi-functionalities. In our solution, hydroxyapatite powder was mixed with a chemically synthesized silicon dioxide/silver (nSiO2/Ag) nanocomposite in a different weight ratio between components (1:1, 5:1, and 10:1) and then electrophoretically deposited on the surface of the NiTi alloy, under various time and voltage conditions. Subsequently, uniform layers were subjected to heat treatment at 700 °C for 2 h in an argon atmosphere to improve the strength of their adhesion to the NiTi substrate. A change in linear dimensions of the co-deposited materials during the sintering process was also analyzed. After the heat treatment, XRD, Raman, and Scanning Electron Microscopy (SEM) + Energy Dispersive Spectrometer (EDS) studies revealed the formation of completely new composite coatings, which consisted of rutile and TiO2-SiO2 glass with silver oxide and HAp particles that were embedded into such coatings. It was found that spalling characterized the 1:1 ratio coating, while the others were crack-free, well-adhered, and capable of deformation to 3.5%. Coatings with a higher concentration of nanocomposite were rougher. Electrochemical impedance spectroscopy (EIS) tests in Ringer's solution revealed the capacitive behavior of the material with high corrosion resistance. The kinetics and susceptibility to pitting corrosion was the highest for the NiTi electrode that was coated with a 5:1 ratio HAp/nSiO2/Ag hybrid coating.

Pro-death signaling of cytoprotective heat shock factor 1: upregulation of NOXA leading to apoptosis in heat-sensitive cells

Heat shock can induce either cytoprotective mechanisms or cell death. We found that in certain human and mouse cells, including spermatocytes, activated heat shock factor 1 (HSF1) binds to sequences located in the intron(s) of the PMAIP1 (NOXA) gene and upregulates its expression which induces apoptosis. Such a mode of PMAIP1 activation is not dependent on p53. Therefore, HSF1 not only can activate the expression of genes encoding cytoprotective heat shock proteins, which prevents apoptosis, but it can also positively regulate the proapoptotic PMAIP1 gene, which facilitates cell death. This could be the primary cause of hyperthermia-induced elimination of heat-sensitive cells, yet other pro-death mechanisms might also be involved.

Screening for Mollicutes microorganisms in perinatal calf mortality cases in Polish dairy herds

Perinatal calf mortality in dairy herds has been reported worldwide. The etiology of stillbirth is multifactorial, and can be caused by various species of bacteria and environmental factors. Among them some potential pathogens from the Mollicutes class such as Mycoplasma (M.) spp. and Ureaplasma (U.) diversum can be isolated from the bovine genital tract and other organs of the suspected cattle. The aim of this study was to evaluate if the bacteria belonging to the Molli- cutes class i.e. M. bovis, M. bovigenitalium, M. canadense, M. canis, M. arginini, M. bovirhinis, M. dispar, M. alkalescens and U. diversum could have an impact on perinatal calf mortality in selected Polish dairy farms. The material was: 121 stillborn calves (SB), 21 live born calves (C) and 131 cows (dams) from 30 Polish Holstein-Friesian herds. Samples were examined from all the SB calves' and six control euthanized calves' abomasal contents and lung samples collected during necropsy, and from the dams' serum and placenta. In dams the serological ELISA, and in calves and placenta samples molecular PCR/denaturing gradient gel electrophoresis, methods were used. Screening of dams' sera for antibodies to M. bovis (ELISA) showed seven dams positive for M. bovis, whereas none of the nine examined Mollicutes microorganisms were detected in the placenta and calves.

Impact of temperature on the physicochemical, structural and biological features of copper-silica nanocomposites

Classical wet chemical synthesis was used to fabricate a hybrid composite that contained copper nanoparticles (average size ∼1 nm), which were embedded into a silicon oxide carrier. The structural and chemical alternations in the copper-functionalized silica were investigated in systems that were sintered at 573 K, 873 K, 1173 K, and 1473 K. A general trend, which was associated with the transformation of metallic copper with a cubic structure into copper(II) oxide with a monoclinic structure in the heat-treated systems, was found. XPS and FTIR spectroscopies also revealed the presence of copper(I) oxide, which formed a shell around the CuO. SEM and TEM showed gradual densification of the hybrid system at ever higher sintering temperatures, which corresponded with the gradual copper agglomeration. A temperature of 873 K was determined to be the temperature at which amorphous silica was transformed into cristoballite and tridymite, as well as the formation of a bulk-like copper structure. In relation to the physicochemical and structural data, high antimicrobial features that had a relatively low toxicity effect on the normal human fibroblasts (NHDF) below 250 mg/L was found for the initial copper-silica composite and the samples that were sintered at 573 K. In turn, a significant decrease in the biological impact was observed in the samples that were sintered at temperatures above 573 K. As a result, the paper discusses the model of structural modifications in copper-silica nanocomposite concerning their biological impact that was developed.

Evaluation of Serum Acute Phase Protein Concentrations in Dogs with Circumanal Gland Tumours

The aim of this study was to determine the serum concentrations of acute phase proteins (APPs), including C-reactive protein (CRP), serum amyloid A (SAA) and haptoglobin (Hp) in dogs with circumanal gland tumours. Investigations were conducted on 39 male dogs of mixed breed. The animals were divided into four groups depending on the degree of tumour malignancy and type of hormones that were dominant in the bloodstream. All measurements of serum APPs were conducted by the use of commercial diagnostic kits. In dogs with benign tumours, the concentrations of each APP decreased during therapy, while in dogs with malignant tumours, despite anti-tumour therapy, concentrations of APPs in serum increased markedly. The results of this study suggest that changes in serum concentrations of CRP, SAA and Hp during anti-hormone therapy may be a reliable marker for differentiating tumour grade and degree of malignancy. Including APPs in routine diagnostics may assist with formulating a prognosis for the outcome of the disease, before implementing anti-tumour therapy. Moreover, monitoring the effectiveness of therapy may be possible based on the determination of serum APP concentrations.

Physicochemical and structural features of heat treated silver-silica nanocomposite and their impact on biological properties

In the last few decades, many nanostructures with varying properties and possible applications have been developed. These materials have been intended to work in various environmental temperature conditions. In this context, the main challenge has been to comprehend the impact of synergic interaction between individual elements included in non-annealed materials in relation to systems subjected to temperature impact. Another problem has corresponded to the impact of thermal modification on organisms such as bacteria and human cells. Such problems can be solved by the fabrication of a nanocomposite with mono-dispersed 8 nm silver (Ag⁰ or Ag⁺) embedded into a silica carrier, followed by the analysis of the impact of heat treatment under various temperature conditions on its physicochemical features. Therefore, methodical studies reported in this text have shown an increase of silver particle size up to 170 nm, a decrease of its concentration, as well as the formation of sub-nanometer Ag⁺ and/or Ag²⁺ clusters as the temperature rises to 1173 K. In turn, the structurally disordered silica carrier had been entirely transformed to cristobalite and tridymite only at 1473 K as well as partial reduction of Ag²⁺ to Ag⁺. Simultaneously, inhibition of growth of Gram-positive and Gram-negative bacteria, as well as an increase in cytotoxicity towards human cells was observed as the temperature rose. As a final point, for the first time, a "pseudo" phase diagram of the structural alterations in the Ag/SiO₂ nanocomposite has been created, as well as a model of silver-silica transformation to biological systems has been developed.

Toward the Development of an Innovative Implant: NiTi Alloy Functionalized by Multifunctional β-TCP+Ag/SiO2 Coatings

In recent years, one of the more important and costly problems of modern medicine is the need to replace or supplement organs in order to improve the quality of human life. In this field, promising solutions seem to have been implants which are based on NiTi alloys with shape memory effects. Unfortunately, this material is susceptible to the corrosion and release of toxic nickel to the human organism. Hence, its application as a long-term material is strongly limited. Therefore, this paper presents a new solution which should help to improve the functionality of the NiTi alloy and elongate its medical stability to use. The idea was focused on functionalization of the implant surface by a biocompatible, multifunctional coating without any impact on the features of the substrate, i.e., the martensitic transformation responsible for shape memory effects. For this purpose, we prepared a colloidal suspension, composed of β-TCP (particle size ∼450 nm) and the Ag/SiO₂ nanocomposite which due to the electrophoretic deposition (EPD) led to the formation of structurally atypical calcium phosphosilicate coating. Those biomaterials formed a crack-free coating, adhering well to the NiTi surface when distributed over the entire surface, with low concentration of metallic and oxide silver (<3 at. %). At the same time, the coat-forming materials had resulted in the growth of a Gram-negative bacterial biofilm. Additionally, the additive of the silver-silica composite enhances cell proliferation, effectively a few times higher than commonly used coat-forming materials (e.g., pure β-TCP).

Evaluation of T regulatory lymphocytes and serum concentration of selected cytokines in dogs with perianal tumors

The purpose of this study was to determine concentrations of IL-2, IL-10, TGF-β1 in serum and T regulatory cell (Treg) percentage in peripheral blood of dogs with perianal tumours. Investigations were conducted on 32 male dogs of mixed breed. The animals were divided into 4 experimental groups and control group. The groups were established depending on the tumour malignancy degree and the type of dominant hormones. All measurements of serum cytokine concentrations were conducted by the use of commercial diagnostic ELISA kits. Treg lymphocyte percentage was measured by flow cytometry. In both groups with benign tumours cytokine levels decreased during therapy, whilst in groups with malignant tumors, in spite of applying anti-tumour therapy, concentrations of cytokines in serum markedly increased. The mean percentage of Treg lymphocytes in dogs with benign tumours (group I and II) was significantly lower than the mean percentage of these cells in control group at all time points, but after applying of anti-hormonal therapy, the significant increase of Treg percentage was observed compared to baseline values. By contrast, in both groups with malignant tumours (group III and IV), the mean percentage of Treg lymphocytes was significantly higher at the beginning of the experiment comparing with the control group as well as both groups with benign tumours and this percentage increased during anti-tumour therapy. The results of this study suggest that monitoring changes in cytokine serum concentrations and Treg percentage in the bloodstream during anti-hormonal therapy may constitute a subsidiary marker in the monitoring of therapy effectiveness, in prognosis the outcome of a disease or in differentiating tumour degree of malignancy.

Divergence history of the Carpathian and smooth newts modelled in space and time

Information about demographic history is essential for the understanding of the processes of divergence and speciation. Patterns of genetic variation within and between closely related species provide insights into the history of their interactions. Here, we investigated historical demography and genetic exchange between the Carpathian (Lissotriton montandoni, Lm) and smooth (L. vulgaris, Lv) newts. We combine an extensive geographical sampling and multilocus nuclear sequence data with the approximate Bayesian computation framework to test alternative scenarios of divergence and reconstruct the temporal and spatial pattern of gene flow between species. A model of recent (last glacial period) interspecific gene flow was favoured over alternative models. Thus, despite the relatively old divergence (4-6 mya) and presumably long periods of isolation, the species have retained the ability to exchange genes. Nevertheless, the low migration rates (ca. 10(-6) per gene copy per generation) are consistent with strong reproductive isolation between the species. Models allowing demographic changes were favoured, suggesting that the effective population sizes of both species at least doubled as divergence reaching the current ca. 0.2 million in Lm and 1 million in Lv. We found asymmetry in rates of interspecific gene flow between Lm and one evolutionary lineage of Lv. We suggest that intraspecific polymorphism for hybrid incompatibilities segregating within Lv could explain this pattern and propose further tests to distinguish between alternative explanations. Our study highlights the importance of incorporating intraspecific genetic structure into the models investigating the history of divergence.

Molecular Inversion Probes for targeted resequencing in non-model organisms

Applications that require resequencing of hundreds or thousands of predefined genomic regions in numerous samples are common in studies of non-model organisms. However few approaches at the scale intermediate between multiplex PCR and sequence capture methods are available. Here we explored the utility of Molecular Inversion Probes (MIPs) for the medium-scale targeted resequencing in a non-model system. Markers targeting 112 bp of exonic sequence were designed from transcriptome of Lissotriton newts. We assessed performance of 248 MIP markers in a sample of 85 individuals. Among the 234 (94.4%) successfully amplified markers 80% had median coverage within one order of magnitude, indicating relatively uniform performance; coverage uniformity across individuals was also high. In the analysis of polymorphism and segregation within family, 77% of 248 tested MIPs were confirmed as single copy Mendelian markers. Genotyping concordance assessed using replicate samples exceeded 99%. MIP markers for targeted resequencing have a number of advantages: high specificity, high multiplexing level, low sample requirement, straightforward laboratory protocol, no need for preparation of genomic libraries and no ascertainment bias. We conclude that MIP markers provide an effective solution for resequencing targets of tens or hundreds of kb in any organism and in a large number of samples.

A serological and molecular study on the occurrence of mycoplasmas in European bison (Bison bonasus) from two areas of Eastern Poland

European bison (Bison bonasus) from two different areas of Eastern Poland showing gross pathology possibly associated with mycoplasma infections were tested for ruminant Mycoplasma species using serological and molecular methods. Fifty-five samples, blood or tissue were collected from 28 animals during 2013-2014. Six sera were positive for Mycoplasma bovis. The ELISA and complement fixation test for Mycoplasma mycoides subsp. mycoides gave a few weak reactions, but were negative by immunoblotting and molecular methods.

Influence of season and nutritional status on the direct effects of leptin, orexin-A and ghrelin on luteinizing hormone and growth hormone secretion in the ovine pituitary explant model

The aim of this study was to examine whether leptin (anorexigenic peptide), orexin-A, and ghrelin (orexigenic peptides) could directly (ie, independently of hypothalamic influences) affect the secretion of luteinizing hormone (LH) and growth hormone (GH) by adenohypophyseal (AP) explants obtained from normally fed or fasted (48 h) ewes during the breeding and nonbreeding seasons. In addition, a specific ovine super leptin antagonist (SLAN-3) was used to assess the interactions between leptin and ghrelin and/or orexin-A. Pituitary glands from 16 ovariectomized Polish Longwool ewes that had received estradiol-releasing subcutaneous implants were collected in the breeding (November; n = 8) and nonbreeding (May; n = 8) seasons. The AP explants were incubated for 240 min in a gas-liquid interface and treated with leptin (50 ng/mL), ghrelin (100 ng/mL), orexin-A (100 ng/mL), and SLAN-3 (500 ng/mL) with orexin-A or ghrelin. Treatments with leptin and SLAN-3 + orexin-A increased (P < 0.05) LH concentrations in the cultures of AP explants from fasted animals in the breeding season. Orexin-A increased (P < 0.05) LH secretion by AP explants from both fasted and fed animals in the breeding season. Ghrelin stimulated (P < 0.05) GH secretion by AP explants collected from fasted animals in nonbreeding season and from normally fed ewes in both seasons. Leptin decreased (P < 0.05) GH secretion by AP explants collected from fasted ewes in both seasons and from nonfasted ewes in the breeding season. However, the treatment with SLAN-3 + ghrelin resulted in greater (P < 0.05) GH concentrations compared with leptin treatment of AP explants from fasted ewes in the breeding season and from normally fed ewes in nonbreeding season. In summary, leptin, orexin-A, and ghrelin exerted direct effects on AP secretory function in an ex situ model and both the reproductive season and nutritional status of the animals impinged on the direct effects of the peptides on LH and GH release. Specifically, orexin-A was more potent than leptin in directly stimulating LH secretion in cycling ewes, whereas ghrelin and leptin generally had opposing effects on the secretory function of somatotrophs in sheep.

Development, validation and high-throughput analysis of sequence markers in nonmodel species

DNA sequences derived from multiple regions of the nuclear genome are essential for historical inferences in the fields of phylogeography and phylogenetics. The appropriate markers should be single-copy, variable, easy to amplify from multiple samples and easy to sequence using high-throughput technologies. This may be difficult to achieve for species lacking sequenced genomes and particularly challenging for species possessing large genomes, which consist mostly of repetitive sequences. Here, we present a cost-effective, broadly applicable framework for designing, validating and high-throughput sequencing of multiple markers in nonmodel species without sequenced genomes. We demonstrate its utility in two closely related species of newts, representatives of urodeles, a vertebrate group characterized by large genomes. We show that over 80 markers, c. 600 bp each, developed mainly from 3' untranslated transcript regions (3'UTR) may be effectively multiplexed and sequenced. Data are further processed using standard, freely available bioinformatic tools, producing phase-resolved sequences. The approach does not require barcoded PCR primers, and the cost of library preparation is independent of the number of markers investigated. We hope that this approach will be of broad interest for researchers working at the interface of population genetics and phylogenetics, exploring deep intraspecific genetic structure, species boundaries and phylogeographies of closely related species.

Consumption of unpasteurized milk and its effects on atopy and asthma in children and adult inhabitants in rural Poland

BACKGROUND

Consumption of unpasteurized cow's milk has been identified as a possible protective factor for atopy and asthma. Most studies have been conducted among children and in farming populations. We investigated the effects of consumption of unpasteurized milk in early life on atopy, asthma, and rhinitis in village and town inhabitants in a region of Poland and assessed whether any protective effects of milk consumption differed according to place of residence and farming status.

METHODS

We surveyed the inhabitants (aged >5 years) of a small town and seven nearby villages in southwest Poland (n = 1700, response rate 88%). Participants (or their parents for those <16 years of age) completed a questionnaire on farm exposures and symptoms of asthma and rhinitis. In particular, information was collected on unpasteurized milk consumption in early life. Atopy was assessed using skin prick tests.

RESULTS

Consumption of unpasteurized milk in the first year of life was inversely associated with atopy and asthma both among town and village inhabitants - town: adjusted odds ratio (aOR) for atopy 0.46 [95% confidence interval (CI) 0.37-0.52] asthma 0.51 (0.32-0.74); villages: atopy 0.59 (0.44-0.70) and asthma 0.59 (0.42-0.74). For atopy, the protective effect was more clearly seen among nonfarmers (0.42; 0.34-0.46) than in farmers (0.82; 0.54-1.11). For doctor-diagnosed hay fever and current rhinitis symptoms, the protective effect was only observed among town inhabitants and/or nonfarmers.

CONCLUSIONS

Early-life exposure to unpasteurized milk may protect against atopy, asthma, and related conditions, independently of place of residence and farming status, and in both children and adults.

Influence of selected factors on survival after liver retransplantation

OBJECTIVE

The aim of this study was to examine the survival of adult liver retransplant recipients depending on selected factors: time from the primary transplantation, cold ischemia time, indications for retransplantation, patient age and United Network for Organ Sharing (UNOS) status.

PATIENTS AND METHODS

Between December 1989 and March 2011, we performed 43 orthotopic liver retransplantations (re-OLTs) among patients aged 20-62 years including 24 women and 19 men. The cold ischemia time was 250-820 minutes. UNOS status before re-OLT: UNOS 1 (n=19; 44%) UNOS 2A (n=15; 35%), and UNOS 2B (n=4; 9%). The time from OLT to re-OLT was 1-2, 146 days. The indications for re-OLT were arterial thrombosis (n=14; 33%), anastomotic biliary complication (n=3; 7%), recurrence of the original disease (n=9; 21%), hepatic vein thrombosis (n=1; 2%), primary nonfunction (PNF) dysfunction (n=2; [5%] /6 [14%]), de novo hepatitis C cirrhosis (n=2; 5%) and other etiologies (n=6; 14%).

RESULTS

The 6-year survival among the primary OLT group was 80% compared with 58% among the re-OLT group (P=.0001). One-year survivals in the re-OLT group according to UNOS status 1, 2A, and 2B were 47%, 60%, and 75%, respectively (P=.475). There was a low negative correlation between survival time and time between OLT and re-OLT. There was a low positive correlation between survival time and cold ischemia time. There was a low negative correlation between survival time and patient age.

CONCLUSIONS

There was a significant difference in survival between OLT and re-OLT. There was a correlation between survival time and time to re-OLTx; a shorter time corresponded to longer survival. There was a poor correlation between survival time and patient age. UNOS status before re-OLT and indication for re-OLTx influenced survival.

Prediction of graft loss and death in patients with primary sclerosing cholangitis

BACKGROUND

The prognosis of patients with primary sclerosing cholangitis (PSC) can be accurately determined using the Mayo Clinic Score (MRS), a mathematical model which predicts patient survival. The purpose of our study was to determine the risk of graft loss and/or death among patients who were listed or transplanted because of PSC.

PATIENTS AND METHODS

We analyzed the data of 52 patients, who were placed on the transplant list due to PSC between January 2000 and November 2008 and either did or did not undergo liver transplantation (OLT). The primary end point (EP1) of the study was the patient death for any cause. The secondary end point (EP2) was recurrence of PSC or appearance of CCC or death related to the primary liver disease after OLT (PSC recurrence). The observation time was 60 months. According to the calculated MRS, patients were divided into 3 groups: group A (MRS < 0.56); group B (0.56 < or = MRS < 1.56), and group C (MRS > 1.56). The analysis was performed using the LIFETEST and PHREG Procedures of the SAS System.

RESULTS

The risk of EP1 occurrence was 2.0 per 1 point of MRS (P < .0006). The risk of EP2 was 2.1 per 1 point of MRS (P < .001). Groups B and C compared with group A showed risks of death of: 0.79 (P = NS) and 6.59 (P < .08), respectively. The percentage of 5-year patient survival rate were 94%, 94%, and 45% according to groups A, B, and C, respectively.

CONCLUSION

The risk of death in patients with MRS > 1.56 was 6.59-fold higher than those with MRS < 0.56. MRS > 1.56 significantly decreased 5 year survival among patients with primary sclerosing cholangitis.

Impact of tumor characteristic on the outcome of liver transplantation in patients with hepatocellular carcinoma

INTRODUCTION

Orthotopic liver transplantation (OLT) is a well-established treatment for cirrhotic patients with hepatocellular carcinoma (HCC) who meet the Milan criteria. The aim of this study was to identify predictors of survival among 65 patients with HCC in cirrhotic livers who underwent liver transplantation (OLT).

METHODS

From January 2001 to December 2008, we performed 655 OLT in 615 patients. HCC was diagnosed in 58 patients before OLT and in 65 by histological examination of the explanted livers; 74% of the patients met Milan criteria by histological examination.

RESULTS

The median follow-up was 27 months (range = 1-96). We analyzed patient age and gender, etiology of liver disease, Child score at transplantation, rejection episodes, tumor number/size, vascular invasion, and differentiation grade. There was no significant difference in survival among patients grouped according to the Model for End-stage Liver Disease staging system for HCC. The 5-year survival of patients with low differentiated (G3) HCC was significantly worse than that of those with moderately differentiated (G2) or well-differentiated (G1) HCC: 50%, 81%, and 86% respectively, (P < .01). Patients with microvascular invasion displayed a worse 5-year survival than those without vascular invasion (42% vs 80%; P < .01).

CONCLUSIONS

The analysis indicated that the histological grade of the tumors and evidences of microscopic vascular invasion were the most useful predictive factors for overall survival among patients with cirrhosis after liver transplantation for HCC.

Early expression of hepatocyte growth factor, interleukin-6, and transforming growth factor-beta1 and -beta2 in symptomatic infection in patients who have undergone liver transplantation

INTRODUCTION

Early septic complications may be a deciding factor for successful recovery among patients who have undergone orthotopic liver transplantation. Therefore, monitoring liver function parameters plays an important role in postoperative treatment to achieve an early diagnosis of postsurgical complications. We ought to measure standard liver function parameters and the expression levels for selected cytokines among patients exhibiting symptoms of infection after orthotopic liver transplantation.

MATERIALS AND METHODS

The study was performed on 30 patients who were divided into two groups: SI-0 consisted of patients free of infection, and SI-1, those who had symptoms of infection. We determined standard liver function parameters and expression of hepatocyte growth factor (HGF), interleukin (IL)-6, transforming growth factor (TGF)-beta1, and TGF-beta2.

RESULTS

There were no significant differences in standard liver function parameters between the two groups of patients. There were no significant differences in the levels of expression for the cytokines in question between the two groups of patients.

CONCLUSIONS

Although standard liver function parameters provide diagnostically valuable information on the patient's condition, they cannot be used to determine the extent of systemic infection among patients showing signs of infection after liver transplantation. Determining gene expression levels in circulating lymphocytes is a sensitive method to monitor patients' condition after liver transplantation. The expression levels of HGF, IL-6, TGF-beta1, and TGF-beta2 in circulating lymphocytes were not sufficiently specific to diagnose transitory postsurgical complications such as symptomatic infection.

Influence of mechanical hippotherapy on skin temperature responses in lower limbs in children with cerebral palsy

Therapeutic horse riding is often employed for disabled children. The aim of the present paper was to determine the influence of exercise in a mechanical saddle, imitating horse's walk, on the skin temperature responses in lower limbs in children with cerebral palsy. Sixteen children, aged 14-16, were enrolled into the study. Skin surface temperature was assessed with thermography, using an infrared thermovision camera, AGEMA 550, before and directly after 20 +/-5 min of exercise. The findings demonstrate that mechanical hippotherapy provides an exercise stimulus that is capable of inducing a visible change in skin temperature of paralyzed limbs. The change, however, is one of a decrease in skin temperature, which points to acute vasoconstrictive effects of exercise and to decreased skin blood flow. The results, therefore, do not support the use of mechanical hippotherapy in children suffering from cerebral palsy, with a hope to stimulate blood circulation to spastically altered limb muscles and thereby to improve physical disability, at least in a short-term exercise paradigm.

The basis function regression in pharmaceutical analysis. Theory and example of application

The BFR (Basis Function Regression) is an interesting alternative to common techniques (such as PCR or PLS) in chemometrics. It is based on projecting the spectral information onto some number of equally spaced spline bases, than obtaining integrals of resulted curves. Existing references show that in certain cases it can reduce almost twice the RMSEP values. As this technique is not so popular in chemometrics nor applied in pharmaceutical analysis, it is desirable to present its theoretical considerations and implementation (with example MATLAB/Octave code). As an illustrative example we present the chemometric model for content recognition of a tablet (12 possible compounds in binary or ternary combinations) from the UV spectrum of its methanolic extract. The BFR technique gave lowest prediction error and the estimators obtained have more meritorical meaning than in case of PCR, PLS and other techniques used for comparison. In our opinion this technique should be considered in any chemometric approach as it often shows better performance.

Clinical significance of lymphocytes hepatocyte growth factor mRNA expression in patients after liver transplantation

Hepatocyte growth factor (HGF) plays a key role in the regulation of liver regeneration after hepatocyte damage. Changes in HGF gene expression reflect the status of the regeneration process.

AIM

The aim of this study was to ascertain the clinical significance of the expression of HGF among liver transplant patients.

METHODS

Expression of the mRNA of HGF among peripheral blood lymphocytes were measured prior to as well as at 1, 2, 6, and 10 days after liver transplantation in a group of 30 liver recipients.

RESULTS

In first 24 hours after reperfusion, the patients with compromised graft function (group 1) showed persistently higher HGF gene expression after reperfusion compared with patients displaying well-functioning grafts (group 0; P = .0189). Between postoperative days 1 and 10, there was a rapid decrease in gene expression among group 0 compared with group 1 (P = .0155). The significant decrease observed in the both groups reached a certain plateau after 48 hours postoperatively. There was no statistical difference in aminotransaminase levels over the days after liver transplantation. The decreased mRNA HGF expression in lymphocytes preceded the decrease in aminotransferase levels.

CONCLUSIONS

HGF was more sensitive to predict early graft function than prothrombin time, aspartate aminotransferase, and alanine aminotransferase levels. The determination of HGF expression level in lymphocytes after liver transplantation may yield valuable information for evaluation of early graft function.

Primary lymphoma of the liver -- morphological and clinical analysis of 6 cases. Success of aggressive treatment

Histological, clinical and immunohistochemical analysis of 6 cases of primary liver lymphomas (PLL) are presented. PLL represents 4.3% of primary malignant liver tumors diagnosed in our department. The patients were relatively young people, who despite the presence of a large tumor, were in good general health status. There were no signs of scirrhosis, and cancer markers were normal. All lymphomas were CD20, CD79a, BAX positive, CD3, CD30, EMA, CD10, CD5, CD59, c-myc, Bcl2, EBV(LMP), CK negative. The proliferation index (Ki67) was high, ranging from 50-100%. In two cases positive staining for Bcl6 and in another one for cyclin D1 was obtained. The major histological type of the tumor was diffuse large B-cell lymphoma. Positive immunohistochemical results with BAX and the lack of Bcl2, c-myc and CD59 are associated with better prognosis. We have not confirmed the value of Bcl6 and CD10 stains as a predictor of poor outcome. Despite clinically advanced stage at the time of diagnosis, if treated appropriately, the primary lymphoma of the liver has relatively good prognosis (five of our patients are alive).