Emerging therapeutic approaches for peritoneal metastases from gastrointestinal cancers

Peritoneal metastases from gastrointestinal malignancies present difficult management decisions, with options consisting primarily of systemic chemotherapy or major surgery with or without hyperthermic intraperitoneal chemotherapy. Current research is investigating expanding therapeutic modalities, and the aim of this review is to provide an overview of the existing and emerging therapies for the peritoneal metastases from gastrointestinal cancers, primarily through the recent literature (2015 and newer). These include the current data with systemic therapy and cytoreduction with hyperthermic intraperitoneal or pressurized intraperitoneal aerosol chemotherapy, as well as novel promising modalities under investigation, including dominating oncolytic viral therapy and adoptive cellular, biologic, and bacteria therapy, or nanotechnology. The novel diverse strategies, although preliminary and preclinical in murine models, individually and collectively contribute to the treatment of peritoneal metastases, offering hope for improved outcomes and quality of life. We foresee that these evolving treatment approaches will facilitate the transfer of knowledge and data among studies and advance discovery of new drugs and optimized treatments for patients with peritoneal metastases.

Hypertrophic Cardiomyopathy versus Storage Diseases with Myocardial Involvement

One of the main causes of heart failure is cardiomyopathies. Among them, the most common is hypertrophic cardiomyopathy (HCM), characterized by thickening of the left ventricular muscle. This article focuses on HCM and other cardiomyopathies with myocardial hypertrophy, including Fabry disease, Pompe disease, and Danon disease. The genetics and pathogenesis of these diseases are described, as well as current and experimental treatment options, such as pharmacological intervention and the potential of gene therapies. Although genetic approaches are promising and have the potential to become the best treatments for these diseases, further research is needed to evaluate their efficacy and safety. This article describes current knowledge and advances in the treatment of the aforementioned cardiomyopathies.

COVID-19 knowledge among Ukrainian refugees in Poland

Background

The constantly growing refugee population may constitute public health threat in Poland in the context of COVID-19 pandemic. This study objective was to investigate COVID-19 knowledge among Ukrainian refugees in Poland.

Methods

This cross-sectional study was carried out between March-April 2022 among Ukrainian refugees registering in Zielona Góra, Poland. An anonymous, self-administered questionnaire was used which included 10 questions related to COVID-19 knowledge. Each correct answer was given 1 point.

Results

Response rate was 96.0%, 190 Ukrainians responded (mean age 37.8±15.7 years; 42.1% males); 52.1% were living in the cities >50,000 inhabitants; 61.6% reported high SES; 39% higher education; 44.2% were married. The mean knowledge score was 3.47 (SD ± 2.2), 15.8% collected >50% points. The knowledge level was higher among those with higher SES (p < 0.0001) and higher education (p = 0.003); 31.7% stated that SARS-CoV-2 is an animal-human transmitted disease (more with high SES, p = 0.004), 55.0% considered COVID-19 as highly contagious disease (more living in bigger cities, p = 0.04), 26.3% reported that SARS-CoV-2 infection ensures lifetime immunity (more unmarried, p = 0.02); 24.7% correctly stated that compared with 18- to 30-year-olds COVID-19 mortality rate is about 10 times higher in those who are >65 years (more with higher education and high SES; p < 0.05, p = 0.01 respectively), 44.4% - that COVID-19 treatments are now available (more with high SES and higher education; p = 0.03 both). Regarding prevention, 37.0% reported that FFP3 is the most protective type of mask, 43.3% that vaccines effectively protect against COVID-19 (more with high SES; p = 0.006, p < 0.001 respectively).

Conclusions

COVID-19 knowledge among Ukrainian refugees in Poland was far unsatisfactory, in particular among those with lower education and lower SES. Educational campaigns are urgently needed to effectively raise the knowledge level in this vulnerable group to better control the pandemic.

Key messages

• This study results may be used by public health experts to expand educational campaigns targeting Ukrainian refugees in Poland.

• COVID-19 education oriented to Ukrainian refugees in Poland should specifically address deficits of knowledge identified in this study.

Should targeted temperature management be used in cardiogenic shock patients? Systematic review and meta-analysis

BACKGROUND

Therapeutic hypothermia, or targeted temperature management (TTM), is a strategy of reducing the core body temperature of survivors of sudden cardiac arrest, cardiogenic shock (CS) or stroke. Therefore, a systematic literature review and meta-analysis were performed to tackle the question about whether the implementation of TTM is actually beneficial for patients with CS.

METHODS

Study was designed as a systematic review and meta-analysis. PubMed, Cochrane Library, Web of Science and Scopus were searched from these databases inception to July 17, 2022. Eligible studies were those comparing TTM and non-TTM treatment in CS patients. Data were pooled with the Mantel-Haenszel method.

RESULTS

Thirty-day mortality was reported in 3 studies. Polled analysis of 30-day mortality was 44.2% for TTM group and 48.9% for non-TTM group (risk ratio: 0.90; 95% confidence interval: 0.75 to 1.08; p = 0.27). Other mortality follow-up periods showed also no statistically significant differences (p > 0.05). The occurrence of adverse events in the studied groups also did not show statistically significant differences between TTM and non-TTM groups (p > 0.05 for myocardial infarction, stent thrombosis, sepsis, pneumonia, stroke or bleeding events).

CONCLUSIONS

The present analysis shows no significant benefit of TTM in patients with CS. Moreover, no statistically significant increase of the incidence of adverse effects was found. However, further randomized studies with higher sample size and greater validity are needed to determine if TTM is worth implementing in CS patients.

The soluble ST2 levels in patients with depression and comorbid heart failure

Introduction

Depression in HF has become a major issue as the burden of HF has continued to increase, and many studies have suggested poorer outcomes in HF patients reporting depression. The prevalence of major depression in HF is about 20–40 %, which is 4–5 % higher than in the normal population. Soluble ST2 is involved in multiple pathogenetic pathways including cardiac strain, inflammation, and myocardial necrosis with remodeling.

Objectives

The purpose of study was to assess the predictive effect of soluble ST2 (sST2) and depressive symptoms in patients with ischemic HF

Methods

It this observational cross-sectional trial 129 patients with ischemic HF FC II-IV by New York Heart Association and depression were investigated. The diagnosis was verified by laboratory and instrumental methods according to European Society of Cardiology recommendations (2016). Depressive symptoms were evaluated by the Hospital Anxiety and Depression Scale. The ST2 level in blood serum was detected by ELISA method. Statistical analyses were performed using the Statistica 12 (StatSoft, Tulsa, OK, USA).

Results

The prevalence of depression increases with NYHA functional class. With decreasing ejection fraction of left ventricle, levels of sST2 were gradually increased (P for trend < 0.001), as well as the prevalence of depressive symptoms (P for trend < 0.01). Multivariate Cox regression analysis demonstrated that depressive symptoms and elevation of sST2 were both independent predictors of all-cause mortality and HF-related hospitalization.

Conclusions

The serum levels of sST2 and depressive symptoms were independent and additive predictors of all-cause mortality and heart failure-related hospitalization in patients with ischemic HF.

Disclosure

No significant relationships.

Wearing masks in public spaces in Poland during SARS-Cov-2 epidemic: an observational study

Background

Face masks can all be effective means of controlling SARS-CoV-2 transmission. In Poland, obligatory wearing of masks in public spaces was introduced on April 10th, 2020.

Objective

To assess use of masks in public spaces in Poland during the third wave of SARS-Cov-2 epidemic.

Methods

A non-participatory covert observational study was conducted during the 3rd wave, on three dates (20.03/27.03/03.04.2021) at public spaces in 12 provinces with different SARS-Cov-2 infection risks according to the R number. Ten consecutive individuals were observed by each of 91 medical students, using a structured checklist.

Results

Among 3283 observed individuals, the female/male ratios were 1.1/1.1/0.9 on the three dates. Around three quarters were using masks: 76.2% (858/1126) on date 1, 76.3% (867/1137) on date 2; and 79.7% (813/1020) on date 3. Medical masks predominated on all dates (52.4%-50.5%-55.8%), followed by cloth (34.6%-37.6%-33.0%). Location in a closed space (OR = 3.47-2.64-2.84) was associated with higher usage. Participants in sports were about two-three times less likely to use masks (OR = 0.52-0.58-0.34) as compared to other activities. The proportion using masks correctly was as follows: 62.6% (537/858); 63.1% (547/867); 57.7% (469/813) respectively; significant between-gender difference was observed regarding date 1 (date 1: 306/458, 66.8% females vs 231/400, 57.8% males; p = 0.006, date 2: 284/459, 61.9% females vs 263/408, 64.5% males; p = 0.43, and date 3: 232/408, 56.9% females vs 237/405, 58.5% males; p = 0.63). Uncovered noses (55.5%-59.5%) and masks around the neck (18.1%-24.7%) were the most frequent incorrect practices.

Conclusions

The results show an essential difference between governmental regulations and how the general public responds to the SARS-Cov-2 pandemic in the context of mask usage. Medical masks were predominantly used in public spaces, however, almost every third individual wore masks incorrectly.

Key messages

Knowledge translation with the use of adequate communication channels, would be helpful to increase compliance and correct usage. This message can be used to target specific practices when developing public health campaigns which should be then rigorously evaluated for their effectiveness.

Spice related catatonia and its treatment: The case study

Introduction

Synthetic Cannabinoids were recognized as drugs of abuse since 2008, they are sold under various names (Kush, K2, Spice).

Objectives

The Patient N., 17 years old male was admitted to the hospital with a first-time psychotic episode. He is fond of extreme sports (ski jumping, gymnastic and acrobatic elements).

Methods

The patient was fully examined.

Results

Then he was taken to the admission department. About a week before admission he fell, injuring his leg and head. After that he did not sleep, became excited, aggressive, “said strange things”. During the admission patient showed disorganized behavior, agitation, paranoid ideation, beliefs that others were inserting thoughts into his head (“thought insertion”) and that his thoughts could be read by others (“thought broadcasting”), imperative “voices”, bizarre delusional thoughts. The UDT showed positive K2 analysis. The patient was prescribed Diazepam, Zuclopenthixol, Valproic acid. No improvement observed. Haloperidol was prescribed next day. Then Haloperodol was changed to Quetiapine, and after 10 days of treatment no improvement was observed. The patient started to show catatonia symptoms such as elective mutism, mild rigidity, signs of cog-wheeling or clasp-knife rigidity. He experienced anxiety, fear, did not take care of himself. Every day he started to be aggressive, impulsive, started to experience auditory hallucinations. Due to that fact it was decided to prescribe Haloperidol, Chlorpromazine, Phenazepame, Diphenhydramine.That treatment improved behavior.

Conclusions

Thus, the intensive treatment with antipsychotic medications in combination with benzodiazepines and diphenhydramine is much more preferable for the management of the cases of oneiroid catatonia due to the usage of Spice.

Effect of vortioxetine on proinflammatory cytokine levels in patients with heart failure and comorbid depression

Introduction

Several studies have shown impaired cytokine status in both patients with depression and chronic heart failure (HF).

Objectives

to study the effect of vortioxetine on the level of pro-inflammatory cytokines: interleukin -1β (IL-1β) and interleukin - 6 (IL-6).

Methods

there were examined 80 patients with HF with reduced ejection fraction (HFrEF) of ischemic genesis with functional class (FC) II-III (NYHA), 37 patients were without depression, 43 - with mild or moderate depressive disorders. Those with mild or moderate depressive disorders were divided into 2 subgroups: 21 patients received psychotherapy, 22 patients, in addition to psychotherapy, were prescribed vortioxetine at a dose of 10 mg / day in the morning after meals. The control group consisted of 20 healthy individuals. The level of cytokines in the blood was determined by ELISA method.

Results

Patients with CHF have an increase in levels of pro-inflammatory cytokines. Thus, the concentration in the serum of IL-1β was 2.3 times higher than the same indicator in the control group: (56.45 ± 4.17) pg / ml, against (24.71 ± 4.21) pg / ml p <0.001). Depression caused an additional increase in the levels of IL-1β by 13.5% (p <0.05) and IL-6 - by 17.3% (p <0.01). Additional administration of vortioxetine caused a more rapid decrease in blood levels of both IL-1β (HR 0.87 [95% CI 0.72-0.97; p = 0.034]) and IL-6 (HR 0.81 [95% CI 0.68-0.93; p = 0.029]).

Conclusions

Thus, vortioxetine causes a decrease in the concentration of pro-inflammatory cytokines IL-1β and IL-6 in patients with HF and comorbid depression.

Disclosure

No significant relationships.

Truncated Gaussian-Bessel beams for short-pulse processing of small-aspect-ratio micro-channels in dielectrics

In order to control the length of micro-channels ablated at the surface of dielectrics, we use annular filtering apertures for tailoring the depth of focus of micrometric Gaussian-Bessel beams. We identify experimentally and numerically the appropriate beam truncation that promotes a smooth axial distribution of intensity with a small elongation, suitable for processing micro-channels of small aspect ratio. Single-shot channel fabrication is demonstrated on the front surface of a fused silica sample, with sub-micron diameter, high-quality opening, and depth of few micrometers, using 1 ps low-energy (< 0.45 µJ) pulse. Finally, we realize 10 × 10 matrices of densely packed channels with aspect ratio ~5 and a spatial period down to 1.5 μm, as a prospective demonstration of direct laser fabrication of 2D photonic-crystal structures.

Abstract P6-02-02: Uridine diphosphate glucose dehydrogenase is required for hyaluronic acid production and breast cancer invasion

This abstract was withdrawn by the authors.

Isomorphic coalescence of aster cores formed in vitro from microtubules and kinesin motors

We report fluorescence microscopy studies of the formation of aster-like structures emerging from a cellular element-based active system and a novel analysis of the aster condensation. The system consists of rhodamine labeled microtubules which are dynamically coupled by functionalized kinesin motor proteins cross-linked via streptavidin-coated quantum dots (QDs). The aster-shaped objects contain core structures. The cores are aggregates of the QD-motor protein complexes, and result from the dynamic condensation of sub-clusters that are connected to each other randomly. The structural specificity of the aster core reflects a configuration of the initial connectivity between sub-clusters. Detailed image analysis allows us to extract a novel correlation between the condensation speed and the sub-cluster separation. The size of the core is scaled down during the condensation process, following a power law dependence on the distance between sub-clusters. The exponent of the power law is close to two, as expected from a geometric model. This single exponent common to all the contractile lines implies that there exists a time regime during which an isomorphic contraction of the aster core continues during the condensation process. We analyze the observed contraction by using a model system with potential applicability in a wide range of emergent phenomena in randomly coupled active networks, which are prevalent in the cellular environment.

Evaluation of the Escherichia coli HK82 and BS87 strains as tools for AlkB studies

Within a decade the family of AlkB dioxygenases has been extensively studied as a one-protein DNA/RNA repair system in Escherichia coli but also as a group of proteins of much wider functions in eukaryotes. Two strains, HK82 and BS87, are the most commonly used E. coli strains for the alkB gene mutations. The aim of this study was to assess the usefulness of these alkB mutants in different aspects of research on AlkB dioxygenases that function not only in alkylated DNA repair but also in other metabolic processes in cells. Using of HK82 and BS87 strains, we found the following differences among these alkB(-) derivatives: (i) HK82 has shown more than 10-fold higher MMS-induced mutagenesis in comparison to BS87; (ii) different specificity of Arg(+) revertants; (iii) increased induction of SOS and Ada responses in HK82; (iv) the genome of HK82, in comparison to AB1157 and BS87, contains additional mutations: nalA, sbcC, and nuoC. We hypothesize that in HK82 these mutations, together with the non-functional AlkB protein, may result in much higher contents of ssDNA, thus higher in comparison to BS87 MMS-induced mutagenesis. In the light of our findings, we strongly recommend using BS87 strain in AlkB research as HK82, bearing several additional mutations in its genome, is not an exact derivative of the AB1157 strain, and shows additional features that may disturb proper interpretation of obtained results.

Popular species of edible mushrooms as a good source of zinc to be released to artificial digestive juices

Because fruiting bodies of edible mushrooms accumulate elements very effectively, in this study for the first time we aimed at determining the degree of the release of zinc(II) ions to artificial digestive juices imitating the human gastrointestinal tract from freeze-dried popular edible mushroom fruiting bodies, such as Agaricus bisporus, Boletus badius and Cantharellus cibarius. For the analysis, anodic stripping voltammetry method was used. The amount of zinc released to artificial saliva within 1 minute ranged from 0.03 to 1.14 mg/100 g d.w. In gastric juice, the amounts were higher and ranged from 0.75 to 2.07 mg/100 g d.w. depending on the incubation time. After incubation of the freeze-dried edible mushroom fruiting bodies for 1 minute in artificial saliva, 15 in artificial gastric juice and then 150 minutes in artificial intestinal juice, it was found that the concentration of the released zinc in artificial intestinal juice was the highest and amounted to 6.44 mg/100 g d.w. The total average amount of zinc released from Boletus badius was the highest and this was estimated at 4.13 mg/100 g d.w. For the remaining two investigated species of A. bisporus and C. cibarius, the total amounts of zinc released into artificial digestive juices were only slightly lower and were estimated at 2.23 and 3.29 mg/100 g d.w. on average, respectively. It was demonstrated for the first time that mushrooms release zinc to artificial digestive juices imitating conditions in the human digestive tract and are a good source of this element.

The influence of sounds on posture control

PURPOSE

It is still not clear which parameters of sound are the most significant for body reactions and whether the way of sound reception plays a role in body control. The purpose of this study was to determine the influence of frequency, spectrum and loudness of sounds on posture control in healthy women and men.

METHODS

The study subjects were 29 young adults who were submitted to a 60-second standing test in the bipedal stance on the force platform (AMTI). During the tests, 3 sinusoidal sounds with various timing and 2 musical sounds (guitar and piano) of the frequency 225 Hz, 1000 Hz and 4000 Hz were applied through headphones. The centre of pressure (COP) amplitude was registered. The sway area and COP mean velocity were computed.

RESULTS

It was found that high frequency sounds contributed to a significant decrease of sway area values. No significant influence of low frequency sounds on posture control was observed. The influence of the sound spectrum (timbre) on posture control is limited; only the crescendo spectrum improves the body stability in the bipedal stance and not the music spectrum as guitar and piano. The loudness of sound, although extremely high, is not the cause of postural control changing in relation to lower loudness. No effect of gender was found in terms of body stability under different sound conditions.

CONCLUSION

Based on the results, it can be argued that, in general, in a bipedal stance in terms of stability high sound frequency improves posture control, whereas sound spectrum and intensity show a limited impact.

Highly sensitive thermal conductivity measurements of suspended membranes (SiN and diamond) using a 3ω-Völklein method

A suspended system for measuring the thermal properties of membranes is presented. The sensitive thermal measurement is based on the 3ω dynamic method coupled to a Völklein geometry. The device obtained using micro-machining processes allows the measurement of the in-plane thermal conductivity of a membrane with a sensitivity of less than 10 nW/K (+∕-5 × 10(-3) Wm(-1) K(-1) at room temperature) and a very high resolution (ΔK/K = 10(-3)). A transducer (heater/thermometer) centered on the membrane is used to create an oscillation of the heat flux and to measure the temperature oscillation at the third harmonic using a Wheatstone bridge set-up. Power as low as 0.1 nW has been measured at room temperature. The method has been applied to measure thermal properties of low stress silicon nitride and polycrystalline diamond membranes with thickness ranging from 100 nm to 400 nm. The thermal conductivity measured on the polycrystalline diamond membrane support a significant grain size effect on the thermal transport.

Detection of Increased Amounts of Cell-Free Fetal DNA with Short PCR Amplicons

Aim: A digital PCR approach has recently been suggested to detect greater amounts of cell-free fetal DNA in maternal plasma than conventional real-time quantitative PCR (qPCR). Because the digital qPCR approach uses shorter PCR amplicons than the real-time qPCR assay, we investigated whether a real-time qPCR assay appropriately modified for such short amplicons would improve the detection of cell-free fetal DNA.

Method: We developed a novel universal-template (UT) real-time qPCR assay that was specific for the DYS14 sequence on Y chromosome and had a short amplicon size of 50 bp. We examined this “short” assay with 50 maternal plasma samples and compared the results with those for a conventional real-time qPCR assay of the same locus but with a longer amplicon (84 bp).

Results: Qualitatively, both assays detected male cell-free fetal DNA with the same specificity and detection capability. Quantitatively, however, the new UT real-time qPCR assay for shorter amplicons detected, on average, almost 1.6-fold more cell-free fetal DNA than the conventional real-time qPCR assay with longer amplicons.

Conclusions: The use of short PCR amplicons improves the detection of cell-free fetal DNA. This feature may prove useful in attempts to detect cell-free fetal DNA under conditions in which the amount of template is low, such as in samples obtained early in pregnancy.

Clinical evaluation of proinflammatory cytokine inhibitors (sTNFR I, sTNFR II, IL-1 ra), anti-inflammatory cytokines (IL-10, IL-13) and activation of neutrophils after burn-induced inflammation

The study was aimed at evaluating the involvement of sTNFR I, sTNFR II, IL-1 ra, IL-10, IL-13 and reactive oxygen species (ROS) in systemic inflammatory response syndrome (SIRS) development in severely burned children and at assessing the prognostic value of the immunological markers studied. The study comprised 37 patients (17 burned children and 20 controls). Serum levels of the markers determined by means of ELISA and respiratory burst of neutrophils as well as p55 and p75 tumour necrosis factor-alpha (TNF-alpha) receptor expression using flow cytometry were evaluated twice. The burned children presented significantly higher levels of IL-10 and cytokine inhibitors within the first 6-24 h after injury compared with controls (P < 0.05). The decreased oxygen metabolism of neutrophils and increased TNF-alpha receptor expression were found on admission. Moreover, a significant decrease in initially high sTNFR I, sTNFR II, IL-1 ra, IL-10, IL-13 concentrations (P < 0.05) and reduced expression of TNF-alpha receptors (P < 0.05) were observed after burn therapy, whereas ROS generation evidently augmented (P < 0.05). Four of our children who developed hypovolaemic shock revealed a significantly lower ROS generation and higher concentrations of soluble TNF-alpha receptors and IL-1 ra together with IL-10, IL-13 compared with children with good outcome (P < 0.05). Our results revealed the involvement of both ROS, soluble TNF-alpha receptors and IL-1 ra in the development of SIRS in burned children; their monitoring allows for an assessment of the systemic inflammatory reaction activity. The neutrophil BURSTTEST and IL-1 ra might have been clinically helpful markers of SIRS prognosis.

Heat shock response in gastrointestinal tract

Heat shock response is one of the defense mechanisms common to eukaryotic and prokaryotic cells. The highly conserved and ubiquitous heat shock proteins (HSPs) are essential for cell survival during stress. Stress tolerance, i.e., adaptation of cells to stress conditions, is a characteristic feature of heat shock response. The lumen of the gastrointestinal tract is an external environment to the body. Epithelium of the digestive tract is exposed to various stress factors inducing the heat shock response, e.g., bacteria and their toxins, food borne chemical compounds, drugs and diet deficiencies. Other factors like plant lecitins, glutamine or short fatty acids are mild stressors and can modulate the heat shock response in cells. All these factors are presumed to influence the normal microflora that is an integral part of the digestive tract. This review is focused on the induction/modulation of heat shock proteins expression in the epithelium of the gastrointestinal tract by various factors, on the protective role of HSPs and mechanisms leading to stress protection inside the gut. Heat shock response is one of the key mechanisms of maintenance of gastrointestinal tract homeostasis. It is involved in pathogenic bacteria adaptation to life in the digestive tract, especially in colony formation and in their role in infectious processes.

Thermoresponsive polymers as promising new materials for local radiotherapy

We describe a novel thermoresponsive polymeric drug delivery system based on poly(N-isopropylacrylamide) with isotopically labellable end groups [l-tyrosinamide or diethylenetriaminepentaacetic acid (DTPA)] designed for local radiotherapy. The polymers are readily soluble in isotonic aqueous sodium chloride at room temperature and the phase separation is complete at body temperature as proved by DSC measurements. Sufficent binding capacity for radionuclides and chemical stability are demonstrated on 125I and 90Y-labelled polymers.

Genotoxicity of streptozotocin in normal and cancer cells and its modulation by free radical scavengers

Streptozotocin (STZ) is an antibiotic which can be used to induce diabetes in experimental animals in order to have an insight into pathogenesis of this disease. To use STZ as a diabetogenic substance, its molecular mode of action should be elucidated. Using the alkaline comet assay, we showed that STZ at concentrations in the range 0.01-100 micromol/L induced DNA damage in normal human lymphocytes and HeLa cancer cells in a dose-dependent manner. Lymphocytes were able to remove damage to their DNA within a 30-min repair incubation, whereas HeLa cells completed the repair in 60 min. Vitamins C and E at 10 and 50 micromol/L diminished the extent of DNA damage induced by 50 micromol/L STZ. Pretreatment of the lymphocytes with the nitrone spin trap, alpha-(4-pyridil-1-oxide)-N-tert-butylnitrone (POBN) or ebselen, which mimics glutathione peroxidase, or pyrrolidine dithiocarbamate (PDTC) reduced the extent of DNA damage evoked by STZ. The cells exposed to STZ and treated with endonuclease III (Endo III), formamidopyrimidine-DNA glycosylase (Fpg) and 3-methyladenine-DNA glycosylase II (AlkA), the enzymes recognizing oxidized and alkylated bases, displayed greater extent of DNA damage than those not treated with these enzymes. These results suggest that free radicals may be involved in the formation of DNA lesions induced by streptozotocin. The drug can also alkylate DNA bases. This broad range of DNA damage induced by STZ indicates that the drug may seriously affect genomic stability in normal and pathological cells.

Small-angle neutron scattering and differential scanning calorimetry study of associative behaviour of branched poly(ethylene oxide)/poly(propylene oxide) copolymer in aqueous solution

Tetronic RED 9040, a reverse-type [poly(propylene oxide) as terminal blocks] octablock star copolymer with four poly(ethylene oxide)/poly(propylene oxide) arms attached to the ethylenediamine core was studied in D2O at concentrations between 1 and 60 g dL−1in the temperature range from 283 to 353 K. Depending on concentration and temperature, various structures (unimers, random network, micelles, micellar aggregates, micellar networks) were indicated by small-angle neutron scattering (SANS). Some structure characteristics of unimers, micelles and micellar networks have been determined by fitting model scattering functions to the SANS data. A competition between the increasing association number and dehydration of the micelles is suggested as a possible explanation of the observed non-monotonic temperature dependence of the structure parameters of concentrated systems. A partial phase diagram was suggested on the basis of SANS and differential scanning calorimetry (DSC) data and visual inspection of the solutions.

Involvement of the cgtA gene function in stimulation of DNA repair in Escherichia coli and Vibrio harveyi

CgtA is a member of the Obg/Gtp1 subfamily of small GTP-binding proteins. CgtA homologues have been found in various prokaryotic and eukaryotic organisms, ranging from bacteria to humans. Nevertheless, despite the fact that cgtA is an essential gene in most bacterial species, its function in the regulation of cellular processes is largely unknown. Here it has been demonstrated that in two bacterial species, Escherichia coli and Vibrio harveyi, the cgtA gene product enhances survival of cells after UV irradiation. Expression of the cgtA gene was found to be enhanced after UV irradiation of both E. coli and V. harveyi. Moderate overexpression of cgtA resulted in higher UV resistance of E. coli wild-type and dnaQ strains, but not in uvrA, uvrB, umuC and recA mutant hosts. Overexpression of the E. coli recA gene in the V. harveyi cgtA mutant, which is very sensitive to UV light, restored the level of survival of UV-irradiated cells to the levels observed for wild-type bacteria. Moreover, the basal level of the RecA protein was lower in a temperature-sensitive cgtA mutant of E. coli than in the cgtA(+) strain, and contrary to wild-type bacteria, no significant increase in recA gene expression was observed after UV irradiation of this cgtA mutant. Finally, stimulation of uvrB gene transcription under these conditions was impaired in the V. harveyi cgtA mutant. All these results strongly suggest that the cgtA gene product is involved in DNA repair processes, most probably by stimulation of recA gene expression and resultant activation of RecA-dependent DNA repair pathways.

Role of the cgtA gene function in DNA replication of extrachromosomal elements in Escherichia coli

The cgtA gene codes for a common GTP-binding protein whose homologues were found in all prokaryotic and eukaryotic organisms investigated so far. Although cgtA is an essential gene in most bacterial species, its precise functions in the regulation of cellular processes are largely unknown. In Escherichia coli, dysfunction or overexpression of the cgtA gene causes problems in various chromosomal functions, like synchronization of DNA replication initiation and partitioning of daughter chromosomes after a replication round. It is not know how the cgtA gene product regulates these processes. Here we investigated effects of cgtA dysfunction on replication of plasmid and phage replicons. We found that replication of some plasmids (e.g., ColE1-like) is not affected in the cgtA mutant. On the other hand, dysfunction of the cgtA gene caused a strong inhibition of lambda plasmid DNA replication. Bacteriophage lambda development was severely impaired in the cgtA mutant. Replication of other plasmid replicons (derivatives of F, R1, R6K, and RK2) was influenced by the cgtA mutation moderately. It seems that DNA synthesis per se is not affected by CgtA, and that this protein might control replication initiation indirectly, by regulation of function(s) or production of one or more replication factors. In fact, we found that level of the host-encoded replication protein DnaA is significantly decreased in the cgtA mutant. This indicates that CgtA is involved in the regulation of dnaA gene expression.

Clinical evaluation of patients with idiopathic juvenile osteoporosis

The aim of this study is to evaluate the occurrence of idiopathic juvenile osteoporosis by clinical, radiographic and biochemical methods in 7 patients aged 10 years to 18 years. The prevailing clinical symptoms included pain in the lower limbs and spine, gait disturbances and weak muscles; confirmed fractures were seen in four out of seven patients. In all patients, bone mineral density was determined by dual-energy X-ray absorptiometry and calcium-phosphorus metabolism assays were performed. Clinical evaluation of our patients revealed a wide variety of classic clinical symptoms, and also radiographic and biochemical features. In this complex evaluation, we can distinguish two types of disease occurrence, mild and acute.

[Selenium plasma concentration level in children with food allergy]

Selenium (Se) is an essential component of many mammalian enzymes and therefore plays an important role in different metabolic processes. Se deficiency occurs in inadequate diet consumption as well as in some digestive tract and allergic diseases. In this research we showed that Se plasma concentration levels in healthy children was 71.8 mg/l, whereas in those with food allergy 54.1 mg/l (with smaller intestinal villus atrophy) or 50.4 mg/l (with greater intestinal villus atrophy). Obtained results indicate that children with food allergy display higher risk of Se deficiency. Antioxidative and immunomodulatory action of Se, connecting with promising literature data of Se supplementation, promote us to state, that this trace element could be used for accessory food allergies treatment.

[Clinical observation of osteoporosis in adolescents]

The aim of the study was to evaluate the occurrence of clinical and biochemical symptoms of osteoporosis in 15 children aged from 10 to 18 years. In this group were 7 children with idiopathic juvenile osteoporosis, 2--with osteogenesis imperfecta and 6 children with secondary osteoporosis. The diagnosis of osteoporosis was based on the result of densitometric examination. The examination was performed with dual-energy X-ray absor-ptiometry (DEXA), with modality by Lunar. Anamnesis and clinical symptoms supported by X-ray examination of the painful region were used as a standard procedure. Biochemical examinations of calcium-phosphorus metabolism included ions and PTH concentrations in blood serum, and the activity of bone isoenzyme of AP. Besides, ions excretion and total hydroxyproline in 24 hrs collection of urine were assessed. The results of our investigations showed that in children with osteoporosis clinical and biochemical abnormalities were various. Pain in the lower limbs and weakening of muscle strength were the most frequently observed clinical symptoms. Among biochemical indices, urine excretion of hydroxyproline and increased concentration of isoenzyme of alkaline phosphatase were of the greatest practical significance.

[Influence of gluten free diet on bone mineral density (BMD) in children with celiac disease]

In children with celiac disease (CD) bone metabolism and mineralization are frequently disturbed. The present study aimed to assess the influence of gluten free diet (GFD) on bone mineral density (BMD) in 73 children with CD, mean age of 12.4 +/- 0.4 years and mean body mass index (BMI) 17.9 +/- 0.4 kg/m2 (mean +/- SEM). Diagnosis of CD was established according to ESPEGAN criteria. Compliance to the GFD was verified on the basis of interview and by estimation of antiendomysial antibodies (IgAEmA/IgGEmA) in blood serum. BMD was measured by dual energy X-ray absorptiometry (DEXA). Plasma calcium (Ca) and phosphorus (P) concentrations, alkaline phosphatase (AP) and its bone fraction (BAP) were estimated before BMD measurement. All children were divided into two groups. Group A consisted of 33 children where gluten free diet was strictly respected for 11.7 +/- 0.6 years. The second group (Group B) comprised 40 children without strictly respected GFD. Children who strictly followed GFD showed statistically higher BMI, AP-spine BMD and total body BMD in comparison with children without GFD (BMI 19 +/- 0.52 kg/m2 vs 17.3 +/- 0.4 kg/m2; p < 0.01, AP-spine BMD 0.951 +/- 0.04 g/cm2 vs 0.767 + 0.03 g/cm2; p < 0.005, Total Body BMD 1.013 +/- 0.02 g/cm2 vs 0.933 +/- 0.01 g/cm2; p < 0.05) respectively. No significant differences were found in plasma Ca, P, AP, BAP between both groups. A statistically significant positive correlation (p < 0.001) was found between duration of GFD and AP-spine BMD and total body BMD, respectively. A statistically significant positive correlation (p < 0.05) was also found between duration of GFD and BMI.

CONCLUSION

Long-term GFD significantly improves BMD and BMI in children with CD.

[AIDS syndrome in an eight-month-old infant]

The paper presents multiorgan manifestations of AIDS syndrome in an infant at the age of 8 months. The child was admitted to the Clinic with enteric disorder, anaemia, hepatosplenomegaly and pneumonia. The diagnosis of those anomalies and the treatment of pneumonia took much time. Infection with CMV was recognized but, despite the treatment and elimination of the virus, the child's condition did not improve and general emaciation progressed. The diagnosis of AIDS syndrome was based upon indicator illnesses: chronic recurrent pneumonia, cytomegaly and emaciation syndrome as well as upon the results of additional examinations, first of all including the presence of p24 antigen in the serum. In children with chronic diseases and manifesting non-specific multiorgan symptoms we should take into consideration AIDS syndrome in the differential diagnosis.

Modulation of interleukin-1beta and tumor necrosis factor alpha signaling by P2 purinergic receptors in human fetal astrocytes

In human astrocytes, interleukin-1beta (IL-1beta) is a potent inducer of genes associated with inflammation. In this study, we tested the hypothesis that in primary cultures of human fetal astrocytes signaling by the P2 purinergic nucleotide receptor pathway contributes to, or modulates, cytokine-mediated signal transduction. Calcium imaging studies indicated that most cells in culture responded to ATP, whereas only a subpopulation responded to UTP. Pretreatment of astrocytes with P2 receptor antagonists, including suramin and periodate oxidized ATP (oATP), resulted in a significant downregulation of IL-1beta-stimulated expression of nitric oxide, tumor necrosis factor (TNFalpha), and IL-6 at both the protein and mRNA levels, without affecting cell viability. In cells transiently transfected with reporter constructs, IL-1beta demonstrated more potent activation of the transcription factors nuclear factor -kappaB (NF-kappaB) and activator protein-1 (AP-1) than TNFalpha. However, pretreatment with oATP downregulated activation of NF-kappaB and AP-1 by IL-1beta or TNFalpha. Electromobility shift assays using oligonucleotides containing specific NF-kappaB binding sequences confirmed that pretreatment with oATP or apyrase attenuated cytokine-mediated induction of this transcription factor. From these data, we conclude that P2 receptor-mediated signaling intersects with that of IL-1beta and TNFalpha to regulate responses to cytokines in the CNS. Because inflammation, trauma, and stress all lead to the release of high levels of extracellular nucleotides, such as ATP and UTP, signaling via P2 receptors may provide a mechanism whereby cells can sense and respond to events occurring in the extracellular environment and can fine tune the transcription of genes involved in the inflammatory response.

Cutting edge: purinergic signaling regulates radical-mediated bacterial killing mechanisms in macrophages through a P2X7-independent mechanism

Signaling by extracellular nucleotides through P2 purinergic receptors affects diverse macrophage functions; however, its role in regulating antimicrobial radicals during bacterial infection has not been investigated. Mycobacterium tuberculosis-infected macrophages released ATP in a dose-dependent manner, which correlated with nitrite accumulation. P2 receptor inhibitors, including oxidized ATP, blocked NO synthase (NOSII) up-regulation and NO production induced by infection with M. tuberculosis or bacille Calmette-Guérin, or treatment with LPS or TNF-alpha. Oxidized ATP also inhibited oxygen radical production and activation of NF-kappaB and AP-1 in response to infection and inhibited NO-dependent killing of bacille Calmette-Guérin by macrophages. Experiments using macrophages derived from P2X7 gene-disrupted mice ruled out an essential role for P2X7 in NOSII regulation. These data demonstrate that P2 receptors regulate macrophage activation in response to bacteria and proinflammatory stimuli, and suggest that extracellular nucleotides released from infected macrophages may enhance production of oxygen radicals and NO at sites of infection.