41 research outputs found
The level of basic knowledge and skills of first aid for students in the eighth grade of primary school
Author: Jaroslav Pejchal, DiS. Institution: Charles University in Prague, Faculty of Medicine in Hradec Králové, Institute of Social Medicine, Department of Nursing Title of Thesis: The level of basic knowledge and skills of first aid for students in the eighth grade of primary school Thesis supervisor: Prof. PhDr. Jiří Mareš, CSc. Page of number: 116 Number of attachments: 5 Year bachelor thesis defense: 2015 Key words: adolescents, first aid, resuscitation, bleeding, coma, shock, trauma, Research My bachelor's thesis deals with the first aid and its knowledge or lack of it among pupils of the 8th form of the basic school. Selected chapters from the first aid and contact of pupils with them during their education and free time activities are described in theoretical part of my thesis. The research part of the thesis tries to find out how effective are first aid lectures for the 8th graders. Whether they can improve pupil's knowledge and skills in first aid or not. 60 pupils of 8th form from one basic school formed the research set. Results from the post-test questionnaire showed improvement in 10 score questions but deterioration in another 6. Concerning difference between sexes, females performed better (8 improvements against 5 deteriorations and 3 without changes) than males (7 improvements..
Mitotic and apoptotic activity in colorectal neoplasia
Abstract Background Colorectal cancer (CRC) is third most commonly diagnosed cancer worldwide. The aim of the prospective study was to evaluate mitosis and apoptosis of epithelial cells at each stage of colorectal neoplasia. Methods A total of 61 persons were enrolled into the study: 18 patients with non-advanced colorectal adenoma (non-a-A), 13 patients with advanced colorectal adenoma (a-A), 13 patients with CRC and 17 controls: individuals with normal findings on colonoscopy. Biopsy samples were taken from pathology (patients) and healthy mucosa (patients and healthy controls). Samples were formalin-fixed paraffin-embedded and stained with haematoxylin-eosin. Mitotic and apoptotic activity were evaluated in lower and upper part of the crypts and in the superficial compartment. Apoptotic activity was also assessed using detection of activated caspase-3. Results In controls, mitotic activity was present in lower part of crypts, accompanied with low apoptotic activity. Mitotic and apoptotic activity decreased (to almost zero) in upper part of crypts. In superficial compartment, increase in apoptotic activity was observed. Transformation of healthy mucosa into non-a-A was associated with significant increase of mitotic activity in lower and upper part of the crypts and with significant increase of apoptotic activity in all three compartments; p < 0.05. Transformation of non-a-A into a-A did not lead to any further significant increase in apoptotic activity, but was related to significant increase in mitotic activity in upper part of crypts and superficial compartment. A significant decrease in apoptotic activity was detected in all three comparments of CRC samples compared to a-A; p < 0.05. No differences in mitotic and apoptotic activity between biopsies in healthy controls and biopsy samples from healthy mucosa in patients with colorectal neoplasia were observed. Detection of activated caspase-3 confirmed the above findings in apoptotic activity. Conclusions Significant dysregulation of mitosis and apoptosis during the progression of colorectal neoplasia, corresponding with histology, was confirmed. In patients with sporadic colorectal neoplasia, healthy mucosa does not display different mitotic and apoptotic activity compared to mucosa in healthy controls and therefore adequate endoscopic/surgical removal of colorectal neoplasia is sufficient
13C and 119Sn NMR spectra of some monophenyltin(IV) compounds
The 13C and 119Sn NMR spectra of some monophenyltin(IV) compounds in solution of non-coordinating (CDCl3) and coordinating ((CD3)2SO) solvents have been studied. From the values of δ(119Sn), 1J(119Sn, 13C) and additional 13C NMR parameters the coordination numbers of the central tin atom and the shapes of coordination polyhedra around the tin atom have been evaluated
Ataxia-telangiectasia Mutated Kinase (ATM) as a Central Regulator of Radiation-induced DNA Damage Response
Ataxia-telangiectasia mutated kinase (ATM) is a DNA damage-inducible protein kinase, which phosphorylates plethora of substrates participating in DNA damage response. ATM significance for the cell faith is undeniable, since it regulates DNA repair, cell-cycle progress, and apoptosis. Here we describe its main signalling targets and discuss its importance in DNA repair as well as novel findings linked to this key regulatory enzyme in the terms of ionizing radiationinduced DNA damage
Enzymatic Degradation of Organophosphorus Pesticides and Nerve Agents by EC: 3.1.8.2
The organophosphorus substances, including pesticides and nerve agents (NAs), represent highly toxic compounds. Standard decontamination procedures place a heavy burden on the environment. Given their continued utilization or existence, considerable efforts are being made to develop environmentally friendly methods of decontamination and medical countermeasures against their intoxication. Enzymes can offer both environmental and medical applications. One of the most promising enzymes cleaving organophosphorus compounds is the enzyme with enzyme commission number (EC): 3.1.8.2, called diisopropyl fluorophosphatase (DFPase) or organophosphorus acid anhydrolase from Loligo Vulgaris or Alteromonas sp. JD6.5, respectively. Structure, mechanisms of action and substrate profiles are described for both enzymes. Wild-type (WT) enzymes have a catalytic activity against organophosphorus compounds, including G-type nerve agents. Their stereochemical preference aims their activity towards less toxic enantiomers of the chiral phosphorus center found in most chemical warfare agents. Site-direct mutagenesis has systematically improved the active site of the enzyme. These efforts have resulted in the improvement of catalytic activity and have led to the identification of variants that are more effective at detoxifying both G-type and V-type nerve agents. Some of these variants have become part of commercially available decontamination mixtures
In vivo study of radioprotective effect of NO-synthase inhibitors and acetyl-L-carnitine
In vivo study of radiprotective effect of NO-synthase inhibitors and acetyl-L-carnitine This study investigated the protective effect of two nitric oxide synthase inhibitors N(omega)-Nitro-Larginine methyl ester (L-NAME, 100 mg/kg i.p.) and aminoguanidine (AG, 400 mg/kg i.p.), and an antioxidant acetyl-L-carnitine (ALC, 250 mg/kg i.p., once daily for five days) against radiation-induced damage in Wistar rats. Blood samples were collected 6 hrs after whole-body irradiation with 8 Gy. Plasma concentrations of nitrite+nitrate (NOx) and malondialdehyde (MDA) were measured by highperformance liquid chromatography. A single injection of L-NAME one hour before exposure effectively prevented the radiation-induced elevation of plasma NOx and it reduced 2.6-fold the risk for death during the subsequent 30-day period. Pretreatment with ALC prevented the radiation-induced increase in plasma MDA and it had similar effect on mortality as L-NAME did. Presumably due to its short half-life, the partially iNOS-selective inhibitor and antioxidant AG given in a single dose before exposure did not attenuate MDA and NOx and it failed to significantly improve the 30-day survival. In conclusion, pretreatment with both the nonspecific NOS inhibitor L-NAME and the antioxidant ALC markedly reduce mortality to radiation sickness in rats. The radioprotective effect may be directly related to effective attenuation of the radiation-induced elevation of NO production by L-NAME and of oxidative stress by ALC. Key words: acetyl-L-carnitine; aminoguanidine; ionizing radiation; N(omega)-Nitro-L-arginine methyl este
Elektrochemická detekce 8-hydroxyguaninu s použitím uhlíkových tištěných elektrod modifikovaných vícestěnnými uhlíkovými naotrubičkami s karboxy skupinami
The paper presents the findings of an optimization and validation results of electrochemical detection of 8-hydroxyguanine, a major marker of oxidative stress, using disposable screen-printed carbon electrode (SPCE) modified with carboxy-functionalized multi-walled carbon nanotubes (MWCNTs-COOH). Several types of bare and modified SPCEs were tested and modification with MWCNTs-COOH was found superior in terms of measured current response, level of background currents, and sensitivity in oxidation of 8-hydroxyguanine. The effect of pH and composition of supporting electrolyte on current response and peak potential were also evaluated. Validation parameters were calculated for optimum pH 7 of 0.01moldm(-3) phosphate buffer. The sensor showed the highest sensitivity of 0.0625 mu A dm(3) mu mol(-1) within the linear range 0.3-12 mu moldm(-3) with a limit of detection as low as 0.57 mu moldm(-3). Extended linear range 0.3-240 mu moldm(-3) is feasible with a sensitivity of 0.0523 mu A dm(3) mu mol(-1). Intra-day and inter-day assays within 3days were performed to verify the repeatability of modified screen-printed carbon sensors. Finally, the sensor was utilized for electrochemical monitoring of stability of 8-hydroxyguanine when stored in room temperature, in the refrigerator, or frozen and thawed. [GRAPHICS] .Práce předkládá výsledky optimalizace a validace elektrochemické detekce 8-hydroxyguaninu, hlavního markeru oxidativního stresu, s využitím jednorázové uhlíkové tištěné elektrody (SPCE) modifikované vícestěnnými uhlíkovými nanotrubičkami s karboxy skupinami (MWCNTs-COOH). Bylo testováno několik typů SPCE a modifikace s MWCNTs-COOH vykazovala nejlepší charakteristiky při elektrochemické detekci 8-hydroxyguaninu. Validace byla provedena v 0,01 M fosfátovém pufru při optimálním pH 7. Citlivost stanovení byla 0,0625 mu A dm(3) mu mol(-1), lineární rozsah 0,3 - 12 mu moldm(-3) a detekční limit 0,57 mu moldm(-3). Je možné použít rozšířený lineární rozsah 0,3 - 240 mu moldm(-3) s citlivostí 0,0523 mu A dm(3) mu mol(-1). Byly provedeny intra-day a inter-day analýzy v rozmezí tří dní k verifikaci opakovatelnosti modifikovaného SPCE senzoru. Závěrem byl senzor použit k elektrochemickému monitorování stability 8-hydroxyguaninu při skladování jeho roztoků při pokojové teplotě, v lednici a při zmražování a rozmrazování
Mechanismus alkylchlorformiátem zprostředkované esterifikace karboxylových kyselin ve vodném prostředí
The protection of carboxyl groups by esterification has been the most common method in macroscale and microscale chemistries. The esterification is usually conducted under anhydrous conditions, however, in biol. chem. and related fields, the reaction is of major concern in aqueous environments. Immediate esterification of the carboxyl in aqueous alc. media driven by an alkyl chloroformate and pyridine has been such a method which has found widespread use in many research and industrial laboratories Nevertheless, the reaction mechanism has not yet been investigated, to our knowledge, and is not well understood. Herein, we describe the reaction intermediates and demonstrate that the reaction proceeds via a continual formation of the N-acylpyridinium intermediate decomposed by several reaction channels to the final ester. The understanding of the mechanism could encourage novel laboratory applications of this important esterification method.Ochrana karboxylových skupin esterifikací je nejběžnější metodou v makroměřítku a mikroměřítku chemie. Esterifikace se obvykle provádí za bezvodých podmínek, avšak v chemické biologii a příbuzných oborech je hlavním problémem práce ve vodném prostředí. Metodou, která našla široké využití v mnoha výzkumných a průmyslových laboratoří je přímá esterifikace karboxylu v prostředí vodném alkoholu řízená alkyl-chlorformiátem a pyridinem. Nicméně reakční mechanismus nebyl dosud prozkoumán, pokud je nám známo, a není dobře pochopen. Zde popisujeme reakční meziprodukty a ukazujeme, že reakce probíhá prostřednictvím kontinuální tvorby N-acylpyridiniového meziproduktu, který se rozkládá několika reakčními kroky na konečný ester
Gamma-radiation-induced ATM-dependent signalling in human T-lymphocyte leukemic cells, MOLT-4
ATM kinase (ATM) is essential for activation of cell cycle check points and DNA repair in response to ionizing radiation (IR). In this work we studied the molecular mechanisms regulating DNA repair and cell death in human T-lymphocyte leukemic cells, MOLT-4. Apoptosis was evaluated by flow-cytometric detection of annexin V. Early apoptotic cells were determined as sub-G1 cells and late apoptotic cells were determined as APO2.7-positive ones. Proteins involved in ATM signalling pathway were analysed by Western-blotting. We observed a rapid (0.5 h) phosphorylation of ATM declining after 6 h after irradiation by all the doses studied (1.5, 3.0, and 7.5 Gy). Checkpoint kinase-2 (Chk-2) was also phosphorylated after 0.5 h but its phosphorylated form persisted 4, 2, and 1 h after the doses of 1.5, 3.0, and 7.5 Gy, respectively. The amount of p53 protein and its form phosphorylated on Ser-392 increased 1 h after irradiation (1-10 Gy). The lethal dose of 7.5 Gy caused an immediate induction and phosphorylation of p53 after 0.5 h post-irradiation. At the time of phosphorylation of p53, we found simultaneous phosphorylation of the oncoprotein Mdm2 on Ser-166. Neither ATM nor its downstream targets showed a dose-dependent response after 1 h when irradiated by the doses of 1-10 Gy. MOLT-4 cells were very sensitive to the effect of IR. Even low doses, such as 1.5 Gy, induced apoptosis 16 h after irradiation (evaluated according to the cleavage of nuclear lamin B to a 48-kDa fragment). IR-induced molecular signalling after exposure to all the tested doses was triggered by rapid phosphorylation of ATM and Chk-2. Subsequent induction of p53 protein and its phosphorylation was accompanied by concomitant phosphorylation of its negative regulator, oncoprotein Mdm2, and followed by induction of apoptosis