Transient Anions in Radiobiology and Radiotherapy: From Gaseous Biomolecules to Condensed Organic and Biomolecular Solids

This chapter focuses on the fundamental processes that govern interactions of low‐energy (1–30 eV) electrons with biological systems. These interactions have been investigated in the gas phase and within complex arrangements in the condensed phase. They often lead to the formation of transient molecular anions (TMAs), and their decay by autoionization or dissociation accompanied by bond dissociation. The damage caused to biomolecules via TMAs is emphasized in all sections. Such damage, which depends on a large number of factors, including electron energy, molecular environment, and type of biomolecule, and its physical and chemical interactions with radiosensitizing agents are extensively discussed. A majority of recent findings resulting from experimental and theoretical endeavors are presented. They encompass broad research areas to elucidate important roles of TMAs in irradiated biological systems, from the molecular level to nanoscale cellular dimensions. Fundamental aspects of TMA formation are stressed in this chapter, but many practical applications in a variety of radiation‐related fields such as radiobiology and radiotherapy are addressed

Rola biopsji nerek w rozpoznawaniu przewlekłych chorób nerek

Biopsja nerki pełni istotną rolę w diagnostyce zarówno ostrych nefropatii, jak i przewlekłych. Charakter zmian morfologicznych pomaga w ustaleniu i klasyfikacji procesów chorobowych, jest także źródłem informacji przydatnych w podejmowaniu decyzji terapeutycznych i ustalaniu rokowania chorego. W niniejszym artykule przedstawiono wskazania do biopsji nerki, a także podstawowe informacje dotyczące opracowania materiału i rodzaju badań diagnostycznych angażowanych w opracowanie i interpretację zmian mikroskopowych. Należy podkreślić, że rozpoznanie patologii nerkowej w obrazie mikroskopowym jest badaniem interpretacyjnym, wymagającym - poza właściwym warsztatem histopatologicznym - także pełnej charakterystyki klinicznej bioptowanego pacjenta

Analysis of the ergonomics of e-commerce websites

The following paper includes research about ergonomics of e-commerce web applications. Main purpose of experiment was to compare existing application of Morele.net shop and developed prototype of application using eyetracking examination and survey. The study carried out on a group of 40 students provided heat maps, scan paths, number of fixations and saccades, times to the first fixation in area of interest, task completion times, assessments of both applications in the form of WUP indicators. Based on the qualitative and quantitative analysis, conclusions were drawn confirming the hypothesis put forward in the work that there is an impact of ergonomic placement of navigation elements on the accessibility and usability of the application, as well as the time of performing tasks in it

Acoustic characterization of atmospheric-pressure dielectric barrier discharge plasma jets

In this work, we report the acoustic measurements performed on an atmospheric-pressure plasma jet (APPJ) ignited at various electrical conditions, and attempt to describe the origin of plasma-generated sound waves. The working principle of the APPJ source used for this investigation was based on a DC- pulsed dielectric barrier discharge in a helium flow. Our results indicated that the sound is generated in the plasma core in a glass tube between two cylindrical electrodes, rather than in the plasma jet that extends into the open atmosphere. We also explored the electrical conditions at which the sound level is below 85 dBA; that is, still within the safe level recommended by the National Institute for Occupational Safety and Health. Therefore, our findings can be used to advance our basic and applicable knowledge of APPJs

Peptydy angiotensynowe regulują aktywność angiogenną w hodowlach komórkowych szczurzych guzów przedniego płata przysadki

Wstęp: Angiogeneza to niezbędny etap w procesie formowania i progresji guzów litych. VEGF należy do kluczowych cytokin proangiogennych, syntetyzowanych przez komórki wielu badanych dotychczas guzów, włączając różne typy gruczolaków przysadki. Angiotensyna II należy do czynników regulujących ekspresję VEGF w różnych tkankach, zarówno w warunkach fizjologii, jak i patologii. Co więcej, udowodniono związek układu renina-angiotensyna (układu RA) z indukowanym estrogenami wzrostem naczyń w procesie formowania doświadczalnego guza prolaktynowego przysadki u szczura. Celem pracy było zbadanie wpływu peptydów angiotensynowych (ang II, ang III i ang IV) na wydzielanie VEGF w dwóch hodowlach komórkowych gruczolaka przysadki: w ciągłej hodowli linii guza laktosomatotropowego GH3 oraz w pierwotnej hodowli indukowanego dietylstilbestrolem (DES) guza prolaktynowego szczura. Materiał i metody: Komórki GH3 oraz komórki prolactinoma hodowano odpowiednio w mediach F-10 i F-12, a następnie rozsiewano do studzienek 24-dołkowych płytek hodowlanych (105 komórek GH3 na studzienkę i 106 komórek gruczolaka na studzienkę). Po 12 godzinach preinkubacji komórki inkubowano przez 24 godziny w obecności ang II, ang III lub ang IV w stężeniach 10&#8211;12, 10&#8211;10, 10&#8211;8 lub 10&#8211;6M lub, w przypadku komórek GH3, w obecności ang II (10&#8211;10M) w połączeniu ze specyficznym antagonistą receptora AT1 losartanem lub receptora AT2 - PD123319 w stężeniach 10&#8211;8 lub 10&#8211;7M. Stężenie VEGF w medium hodowlanym oznaczano, wykorzystując metodę ELISA. Analizy statystycznej dokonywano przy użyciu testu t-Studenta oraz na podstawie analizy wariancji (ANOVA), dla poziomu istotności p < 0.05. Wyniki: Inkubacja komórek GH3 lub komórek pierwotnej hodowli guza prolaktynowego w obecności ang II, ang III lub ang IV w stężeniach 10&#8211;12 - 10&#8211;8M prowadziła do wzrostu stężeń VEGF w medium hodowlanym. Przeciwnie, po ekspozycji komórek GH3 na działanie ang III lub ang IV w stężeniach 10&#8211;6M dochodziło do zahamowania wydzielania cytokiny, a krzywa korelacji Persona wykazała dodatkowo tendencję do hamowania wydzielania VEGF w pierwotnej hodowli prolactinoma przez ang II w stężeniach przekraczających 10&#8211;6M. Pobudzający wpływ ang II na sekrecję VEGF przez komórki GH3 znoszony był zarówno przez losartan, jak i PD123319. Wnioski: Ang II, ang III i ang IV wpływają na wydzielanie VEGF przez komórki GH3 oraz komórki gruczolaka prolaktynowego szczura. Zarówno receptory AT1, jak i AT2 pośredniczą w proangiogennym efekcie ang II w hodowli GH3. Mechanizm obserwowanego, hamującego oddziaływania peptydów angiotensynowych na sekrecję VEGF pozostaje niewyjaśniony.Introduction: Angiogenesis has been shown to be necessary for the development and progression of solid tumours. VEGF is one of the crucial pro-angiogenic cytokines produced by the cells of many of the tumours examined, including various types of anterior pituitary adenomas. Angiotensin II (Ang II) is known to regulate the expression of VEGF in a variety of tissues both in the physiological and pathological conditions. Moreover, an association of the renin-angiotensin system (RAS) with oestrogen-induced vascular changes during the development of rat pituitary PRL-secreting adenoma has already been demonstrated. The aim of the study was to determine the in vitro effects of angiotensin peptides (Ang II, Ang III and Ang IV) on the secretion of VEGF in two anterior pituitary adenoma cell cultures: the culture of the rat pituitary lactosomatotrope tumour cell line (GH3) and the primary culture of rat PRL-secreting tumour induced by diethylstilbestrol (DES). Material and methods: GH3 and prolactinoma cells were cultured in an F10 and an F-12 medium respectively and then placed into 24 multiwell plates (105 of GH3 cells/well and 106 of rat prolactinoma cells/well). After 12 hours of preincubation the cells underwent 24-hour treatment with Ang II, Ang III or Ang IV at final concentrations of 10&#8211;12, 10&#8211;10, 10&#8211;8 or 10&#8211;6M and, in the case of the GH3 cells, combined treatment with Ang II (10&#8211;10M) and specific AT1 or AT2 receptor antagonist (losartan or PD123319 respectively at a concentration of 10&#8211;8 or 10&#8211;7 M). The concentration of VEGF in the supernatant collected was determined using specific ELISA assay kits. Statistical evaluation was performed using Student&#8217;s test and analysis of variance (ANOVA). Differences were considered significant if p < 0.05. Results: The incubation of both GH3 cells and rat adenoma cells with Ang II, Ang III or Ang IV at concentrations of 10&#8211;12 &#8211;10&#8211;8M resulted in a significant increase in VEGF concentration in the culture medium. Exposure of GH3 cells to Ang III or Ang IV at concentrations of 10-6M led to a significant inhibition of cytokine release, and Pearson&#8217;s correlation curve showed a tendency for Ang II at concentrations of more than 10&#8211;6M to inhibit VEGF secretion in primary prolactinoma cell culture. The stimulatory influence of Ang II on VEGF secretion in GH3 cell culture was negated by losartan or by PD123319 in both concentrations tested. Conclusions: Ang II, Ang III and Ang IV affect the secretion of VEGF in cultures of the rat lactosomatotrope GH3 cell line and primary rat prolactinoma cells. Both AT1 and AT2 receptors mediate the stimulatory action of Ang II on the cytokine release in GH3 cell culture. The mechanism of the observed anti-angiogenic effects of angiotensin peptides remains unexplained

X-ray induced damage in DNA monitored by X-ray photoelectron spectroscopy

In this work, the chemical changes in calf thymus DNA samples were analyzed by X-ray photoelectron spectroscopy XPS. The DNA samples were irradiated for over 5 h and spectra were taken repeatedly every 30 min. In this approach the X-ray beam both damages and probes the samples. In most cases, XPS spectra have complex shapes due to contributions of C, N, and O atoms bonded at several different sites. We show that from a comparative analysis of the modification in XPS line shapes of the C 1s, O 1s, N 1s, and P 2p peaks, one can gain insight into a number of reaction pathways leading to radiation damage to DNA

Resonance electron interaction with five-membered heterocyclic compounds: Vibrational Feshbach resonances and hydrogen-atom stripping

Low-energy (0–15 eV) resonance electron attachment to a series of five-membered heterocyclic rings (isoxazole, imidazole, pyrazole, pyrrole, 1-methyl-, and 2-methylimidazole) is studied under gas-phase conditions by means of electron transmission spectroscopy and dissociative electron attachment spectroscopy (DEAS). Experimental spectral features are assigned on the basis of Hartree-Fock and density functional theory calculations. Sharp features, with a width of less than 0.1 eV, observed in the electron transmission spectra of imidazole, pyrazole, and pyrrole close to 0.45 eV, i.e., well below the energy of their lowest-lying π∗ shape resonances detected at 1.90, 1.87, and 2.33 eV, respectively, are associated with formation of negative ion states bound by long-range electron-molecule interactions. Effective range theory calculations which include both dipolar and polarization interactions support this interpretation. In addition to the general observation of cleavage of the N–H bond at incident electron energies close to 2 eV, elimination of as many as three hydrogen atoms from the molecular negative ions is detected at higher energies by DEAS with the only exception of methylated imidazoles. This complex process is associated with ring opening and formation of diatomic hydrogen as one of the neutral fragments, as indicated by the calculations to satisfy the energetic requirements. The present results are of importance for understanding the basic mechanisms of damages caused in living tissues by high-energy radiations

The effect of a cold atmospheric pressure plasma jet on DNA

In this study, we have investigated the interaction of a ‘cold’ Atmospheric Pressure Plasma Jet (APPJ) with dry plasmid DNA. The plasmid DNA is observed to be very sensitive to short-term exposures to low energy electrons, ions and excited neutral species as well as to UV light, which are all components of the APPJ fed by helium. In order to determine the mechanisms that lead to strand breaks in the DNA, the APPJ exposure was carried out over a range of operating conditions

Slowly progressive chronic kidney disease caused by tubulointerstitial nephritis in a patient with primary biliary cholangitis

Tubulointerstitial nephritis is a rare complication of primary biliary cholangitis. The most typical presentation is progressive renal disease, and a substantial number of patients have renal tubular acidosis and mild proteinuria. Treatment with steroids is effective, but there are no precise recommendations concerning doses and the duration of therapy. This article presents a case of a 41-year-old woman with primary biliary cholangitis and slowly progressive chronic kidney disease. Renal tubular acidosis and very high urinary β2 microglobulin excretion but no albuminuria were observed. A kidney biopsy revealed a diffuse interstitial inflammatory infiltrate in both cortex and medulla, dominated by T lymphocytes and macrophages, less numerous B lymphocytes, neutrophils, and eosinophils. After initiation of steroids, a rapid 10-fold decrease in β2 microglobulin urine excretion and a mild decrease in serum creatinine were observed. This case shows how mildly symptomatic tubulointerstitial nephritis is in a patient with primary biliary cholangitis. The authors emphasize the importance and crucial role of kidney biopsy