Cold stress effects on organelle ultrastructure in polar Caryophyllaceae species

Abstract: This study investigated leaf mesophyll cells of Caryophyllaceae plants growing in polar regions – Cerastium alpinum and Silene involucrata from the Hornsund region of Spitsbergen island (Svalbard Archipelago, Arctic), and Colobanthus quitensis from the Ad− miralty Bay region on King George Island (South Shetland Islands, West Antarctic). Ultra− structural changes were analyzed in mesophyll protoplasts of plants growing in natural Arctic and Antarctic habitats and plants grown in a greenhouse, including plants exposed to short−term cold stress under semi−controlled conditions. Cell organelles of plants growing in natural polar habitats and greenhouse−grown plants were characterized by significant mor− phological plasticity.Chloroplasts of plants studied in this work formed variously shaped pro− trusions and invaginations that visibly increased the contact area between adjacent cell com− partments and reduced the distance between organelles. S. involucrata plants grown under greenhouse conditions, tested by us in this work, were characterized by highly dynamic cell nuclei with single or multiple invaginations of the nuclear membrane and the presence of channels and cisternae filled with cytoplasm and organelles. Crystalline inclusion proteins were observed in the cell nuclei of C. quitensis between nuclear membranes and in the direct proximity of heterochromatin. Our study revealed significant conformational dynamics of organelles, manifested by variations in the optical density of matrices, membranes and envelopes, in particular in C. quitensis, which could suggest that the analyzed Caryophyllaceae taxa are well adapted to severe climate and changing conditions in polar regions

Radiation-induced DNA damage and repair in human γδ and αβ T-lymphocytes analysed by the alkaline comet assay

It has been shown by a number of authors that the radiosensitivity of peripheral blood mononuclear cells (PBMC) is higher in cancer patients compared to healthy donors, which is interpreted as a sign of genomic instability. PBMC are composed of different cell subpopulations which are differently radiosensitive and the difference between cancer patients and healthy donors could also be due to different composition of their PBMC pools. Gamma-delta T-lymphocytes play an important role in immunosurveillance and are promising cells for immunotherapy. Their abundance is frequently reduced in cancer patients so should their sensitivity to radiation be lower than that of other T-lymphocytes, this could, at least partly explain the low radiosensitivity of PBMC from healthy individuals compared to cancer patients. The present investigation was carried out to test this. Using the alkaline comet assay we analysed the level of DNA damage and repair in isolated γδ T-lymphocytes, pan T-lymphocytes and in total PBMC exposed in vitro to gamma radiation. We found no difference in the level of DNA damage and the capacity of DNA repair between the T cell populations. This is the first study that addresses the question of sensitivity to radiation of gamma-delta T-cells

Liposome-based DNA carriers may induce cellular stress response and change gene expression pattern in transfected cells

<p>Abstract</p> <p>Background</p> <p>During functional studies on the rat stress-inducible <it>Hspa1b </it>(<it>hsp70.1</it>) gene we noticed that some liposome-based DNA carriers, which are used for transfection, induce its promoter activity. This observation concerned commercial liposome formulations (LA), Lipofectin and Lipofectamine 2000. This work was aimed to understand better the mechanism of this phenomenon and its potential biological and practical consequences.</p> <p>Results</p> <p>We found that a reporter gene driven by <it>Hspa1b </it>promoter is activated both in the case of transient transfections and in the stably transfected cells treated with LA. Using several deletion clones containing different fragments of <it>Hspa1b </it>promoter, we found that the regulatory elements responsible for most efficient LA-driven inducibility were located between nucleotides -269 and +85, relative to the transcription start site. Further studies showed that the induction mechanism was independent of the classical HSE-HSF interaction that is responsible for gene activation during heat stress. Using DNA microarrays we also detected significant activation of the endogenous <it>Hspa1b </it>gene in cells treated with Lipofectamine 2000. Several other stress genes were also induced, along with numerous genes involved in cellular metabolism, cell cycle control and pro-apoptotic pathways.</p> <p>Conclusions</p> <p>Our observations suggest that i) some cationic liposomes may not be suitable for functional studies on <it>hsp </it>promoters, ii) lipofection may cause unintended changes in global gene expression in the transfected cells.</p

Olbrzymie uszko lewego przedsionka

Aneurysmal left atrial appendage (LAA) is a rare congenital anomaly. It may result in supraventricular arrhythmias and embolic complications. We present a case of a 33 year-old female in whom echocardiography showed a giant LAA (6 x 3 cm), confirmed by computed tomography. Key words: left atrial appendage, aneurysm, dilation Kardiol Pol 2011; 69, 1: 83-8

Charakterystyka modeli in vitro do badań nad rakiem jajnika

W leczeniu onkologicznym coraz większą rolę odgrywają leki celowane molekularnie. W terapii raka jajnika najbardziej obiecujące wyniki daje zastosowanie leków z grupy inhibitorów polimerazy poliADP-rybozy (PARP). Badania kliniczne ostatnich lat wykazały, że inhibitory PARP stosowane w terapii podtrzymującej wydłużają czas wolny od progresji o wiele miesięcy. To zachęca do poszukiwania kolejnych leków celowanych i stwarza nadzieję, że rak jajnika może się stać chorobą przewlekłą, o wieloletnim przebiegu.Problemem w badaniach nad rakiem jajnika jest heterogenność choroby. Ostatnie badania wskazują, że różne typy histologiczne mogą mieć odrębne pochodzenie tkankowe. Według współczesnej wiedzy określenie „rak jajnika” jest sztucznym pojęciem, obejmującym różne inwazyjne raki zlokalizowane w obrębie miednicy. Badania genetyczne i immunofenotypowe wskazują, że niskozróżnicowany rak surowiczy, najczęstszy i najgorzej rokujący typ histologiczny, w większości przypadków wywodzi się z nabłonka jajowodu, raki endometrioidalne i jasnokomórkowe wywodzą się zaś prawdopodobnie z endometrium. Dlatego w badaniach podstawowych i przedklinicznych nad rakiem jajnika potrzebne są dobrze scharakteryzowane modele odpowiadające poszczególnym typom histologicznym.W niniejszej pracy omówiono najczęściej wykorzystywane linie komórkowe stosowane w badaniach in vitro. Opracowanie ma na celu podsumowanie zalet i ograniczeń różnych modeli, obejmujących hodowle pierwotne i stabilne linie komórkowe, model hodowli dwu- i trójwymiarowej itp. W szczególności autorzy chcą zwrócić uwagę badaczy, że najczęściej stosowane linie komórkowe SKOV3 i A2780 nie są właściwym modelem do badań nad niskozróżnicowanym rakiem surowiczym

Związek zmian regionalnego odkształcenia podłużnego miokardium z odpowiedzią na terapię resynchronizującą serca u pacjentów z dysfunkcją skurczową lewej komory i blokiem lewej odnogi pęczka Hisa

Introduction. Strain and strain rate (SR) are techniques, which provide local information on myocardial deformation. The aim of the study was to assess the usefulness of strain and SR measurement in cardiac resynchronization therapy (CRT) response in chronic heart failure (CHF) patients. Materials and methods. The study included 35 CHF patients with QRS complex duration ≥ 120ms with LBBB morphology. Biochemical and clinical parameters were assessed before and after six months of CRT. TTE classical and tissue Doppler echocardiography parameters (longitudinal peak systolic strain — LPS and SR for basal segment of intraventricular septum and lateral wall) were evaluated. Results. Twenty-two patients (62.8%) benefited from CRT (the responders) and revealed improvement in septal and lateral LPS in the 6-month observation [-7.1 (-5.2– -11.1) vs -12.1 (-8.7– -14)%, p = 0.002; - 10.4 (-6.1– -17.6) vs - 13.8 (-8.9 – -17.8)%, p = 0.03; respectively]. Six months after CRT, the responders were characterised by higher increase in septal LPS comparing to the nonresponders (-4.6 ± 6.1 vs -2.4 ± 3.9%, p = 0.045). Septal LPS changes correlated positively with baseline cardiopulmonary exercise testing (CPET) parameters: peak oxygen uptake (r = 0.6, p = 0.004), peak carbon dioxide excretion (r = 0.62, p = 0.002) and negatively with VE/VCO2 slope (r = -0.5, p = 0.037). Conclusions. LV regional LPS appears to be a good parameter reflecting the improvement of clinical status in patients treated with CRT. The responders had better improvement of septal LPS, therefore positive response to this therapy may be related to the improvement of septal contractility.Streszczenie Wstęp Odkształcenie miokardium i tempo tego odkształcania (strain i strain rate - SR) to metody w tkankowej echokardiografii doplerowskiej wnoszące informacje o regionalnej kurczliwości mieśnia. Celem badania była ocena przydatności pomiarów strain i SR w ocenie odpowiedzi na terapię resynchronizującą (CRT) u chorych z przewlekłą niewydolnością serca (CHF). Materiały i Metody Do badania wlączono 35 pacjentów z CHF i czasem trwania zespołów QRS ≥120ms i morfologią LBBB. Parametry biochemiczne i kliniczne były oceniane przed implantacją i 6 miesięcy po wszczepieniu CRT. Analizie poddano wybrane parametry z badania echokardiograficznego przezklatkowego i metodą Dopplera tkankowego – odkształcenie podłużne miokardium na szczycie skurczu – (longitudinal peak systolic strain – LPS) i tempo odkształcania (strain rate – SR) mierzone dla segmentu przypodstawnego przegrody międzykomorowej i ściany bocznej lewej komory. Wyniki 22 pacjentów (62.8%) odniosło korzyść z CRT i wykazało poprawę w zakresie wartości przegrodowego i bocznego LPS w obserwacji 6-miesięcznej [odpowiednio: - 7,1 (-5,2 - - 11,1) vs – 12,1 (-8,7 - -14)%, p=0,002; - 10,4 (-6,1 - -17,6) vs – 13,8 (-8,9 – -17,8)%, p=0,03]. Osoby odnoszące korzyść z CRT po 6 miesiącach wykazywały większy wzrost przegrodowego LPS w stosunku do nonresponderów (-4.6±6.1 vs -2.4±3.9%, p= 0.045). Zmiany LPS w obrębie przegrody pozytywnie korelowały z wyjściowymi parametrami uzyskanymi w badaniu ergospirometrycznym: szczytowym pochłanianiem tlenu (r=0.6, p=0.004), szczytowym wydalaniem dwutlenku węgla (r=0.62, p= 0.002) oraz negatywnie z VE/VCO2 slope (r= -0.5, p=0.037). Wnioski Regionalne odkształcenie podłużne wybranych segmentów lewej komory jest parametrem odzwierciedlającym poprawę stanu klinicznego pacjentów leczonych terapią resynchronizującą. Chorzy odnoszący korzyść z terapii resynchronizującej wykazują lepszą poprawę przegrodowego LPS, w związku z tym pozytywna odpowiedź na terapię może mieć związek z poprawą kurczliwości w obrębie przegrody międzykomorowej

Biodegradation of Chloroxylenol by Cunninghamella elegans IM 1785/21GP and Trametes versicolor IM 373: Insight into Ecotoxicity and Metabolic Pathways

Chloroxylenol (PCMX) is applied as a preservative and disinfectant in personal care products, currently recommended for use to inactivate the SARS-CoV-2 virus. Its intensive application leads to the release of PCMX into the environment, which can have a harmful impact on aquatic and soil biotas. The aim of this study was to assess the mechanism of chloroxylenol biodegradation by the fungal strains Cunninghamella elegans IM 1785/21GP and Trametes versicolor IM 373, and investigate the ecotoxicity of emerging by-products. The residues of PCMX and formed metabolites were analysed using GC-MS. The elimination of PCMX in the cultures of tested microorganisms was above 70%. Five fungal by-products were detected for the first time. Identified intermediates were performed by dechlorination, hydroxylation, and oxidation reactions catalysed by cytochrome P450 enzymes and laccase. A real-time quantitative PCR analysis confirmed an increase in CYP450 genes expression in C. elegans cells. In the case of T. versicolor, spectrophotometric measurement of the oxidation of 2,20-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) showed a significant rise in laccase activity during PCMX elimination. Furthermore, with the use of bioindicators from different ecosystems (Daphtoxkit F and Phytotoxkit), it was revealed that the biodegradation process of PCMX had a detoxifying nature