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We have previously demonstrated in H295R adrenocortical cells that the Ca

We have previously demonstrated in H295R adrenocortical cells that the Ca2+-dependent production of mitochondrial cAMP (mt-cAMP) by the matrix soluble adenylyl cyclase (sAC; encoded by ADCY10) is associated with enhanced aldosterone production. Here, we examined whether mitochondrial sAC and mt-cAMP fine tune mitochondrial Ca2+ metabolism to support steroidogenesis. Reduction of mt-cAMP formation resulted in decelerated mitochondrial Ca2+ accumulation in intact cells during K+-induced Ca2+ signalling and also in permeabilized cells exposed to elevated perimitochondrial [Ca2+]. By contrast, treatment with the membrane-permeable cAMP analogue 8-Br-cAMP, inhibition of phosphodiesterase 2 and overexpression of sAC in the mitochondrial matrix all intensified Ca2+ uptake into the organelle. Identical mt-cAMP dependence of mitochondrial Ca2+ uptake was also observed in HeLa cells. Importantly, the enhancing effect of mt-cAMP on Ca2+ uptake was independent from both the mitochondrial membrane potential and Ca2+ efflux, but was reduced by Epac1 (also known as RAPGEF3) blockade both in intact and in permeabilized cells. Finally, overexpression of sAC in the mitochondrial matrix potentiated aldosterone production implying that the observed positive feedback mechanism of mt-cAMP on mitochondrial Ca2+ accumulation may have a role in the rapid initiation of steroidogenesis.This article has an associated First Person interview with the first author of the paper.

Introduction: Clinical practice requires knowledge of health professionals for the application of problem solving of different tasks in various clinical settings. Therefore, a set of reliable measurement tools is required to assess various components of the professional knowledge including factual knowledge, skills and competence as outcomes of nursing education and training. Traditional questionnaires and test methods do not allow the measurement of these characteristics properly, as these tools typically provide overall scores without relevant insight into areas in which nurses perform well, and those where their knowledge and/or skills should be improved substantially. Aim: The aim of this nationwide survey conducted among nurses between November 2014 and February 2015 was to determine how the teaching/training objectives have been achieved in the nurses’ transfusion practice. The authors attempted to exceed the capabilities of classical test theory and acquire a detailed picture about what the nurses know about transfusion therapy and how they are involved and behave in routine clinical practice. Method: The knowledge and skills of 657 participants were assessed using a validated instrument consisting of a set of questions covering every aspects of transfusion therapy. The answers to these items were evaluated on a binary (good or bad) scale. Recorded answers of the participants were analysed using hierarchical cluster analysis and item response theory tools such as the one-parametric Rasch model suitable for dichotomous data. Data analysis was performed with the SPSS program and the ltm module of the R statistical program. Results: The paper presents the distribution of correct and incorrect answers to various questions about transfusion therapy along with the corresponding logit values and odds ratios, respectively. The characteristic curves of each item were determined on the basis of the number of correct answers that have been recorded. These curves highlight which questions were answered easily and which items were found harder to answer by the nurses who participated in the survey. In addition to the separate analysis of individual questions, a set of response patterns is also presented which shows how frequently the nurses responded correctly to different combinations (sub-sets) of questions. On the whole, nurses exhibited medium level performance in terms of knowledge and skills required for efficient and safe transfusion practice. Conclusions: Objective and reliable measurement of the level of acquired knowledge is a key requirement in nursing education. This paper, which demonstrates the use of cluster analysis and item response theory for the assessment of transfusion-related knowledge of nurses, focuses on this issue for the first time in nursing research. The results of this survey have revealed substantial limitations and deficiencies both in knowledge and skills of nurses which need to be addressed by training in order to improve the efficiency and safety of transfusion therapy. Orv. Hetil., 2015, 156(37), 1497–1508.

Absztrakt Bevezetes: Nemzetkozi szakirodalmi adatok egyertelműen bizonyitjak, hogy a transzfuzios terapiaban folyamatosan nő az apolok szerepe, amelyet kizarolag komoly szakmai ismeretek es keszsegek birtokaban tolthetnek be. Celkitűzes: A szerzők a transzfuzios terapia gyakorlatanak, az apolok transzfuzios terapiaval, valamint sajat kompetenciaik meghatarozasaval kapcsolatos ismereteinek orszagos szintű felterkepezeset tűztek ki celul. Tovabbi celjuk a hasonlosagok es kulonbozősegek feltarasa volt a kutatas idejen hatalyos Transzfuzios Szabalyzat (2008) előirasainak betartasara vonatkozoan. Modszer: A 2014. november 19. es 2015. februar 20. kozotti intervallumban vegzett orszagos reprezentativ felmereshez sajat keszitesű kerdőivet alkalmaztak. Az adatgyűjtest papir- es webalapu anonim, onkitoltős, standardizalt korulmenyek kozott, retegzett mintaveteli technikaval vegeztek. A vizsgalt mintaba (n = 657 fő) olyan apolokat vontak be, akik felnőtt fekvőbeteg-osztalyon, valtozo rendszeresseggel vettek reszt transzfuzios terapiaban. A keresztmetszeti kutatas adatait első lepesben leiro statisztikai eljarasok segitsegevel dolgoztak fel. Eredmenyek: Megallapitottak, hogy a vizsgalt minta transzfuziologiaval kapcsolatos ismeretei erősen hianyosak (50,72%), az apolasi funkciokat csak az apolok fele (52,3%) rendszerezte helyesen, es jelentős kulonbsegek voltak a transzfuzios terapia gyakorlatara vonatkozoan is. A vizsgalt intezmenyek tulnyomo tobbsege rendelkezett sajat protokollal, de a betegosztalyok mindossze 23,9%-an dolgozott megbizott transzfuzios felelős apolo. Kovetkeztetesek: A szerzők a feltart problemak megoldasat az apolok szakmai felelőssegenek noveleseben, az apolas vezetőinek a jelenleginel nagyobb mertekű felugyeleteben, a megfelelő transzfuziologiai kepzes es rendszeres tovabbkepzes biztositasaban latjak. Orv. Hetil., 2015, 156(34), 1383–1392.

The most frequent form of hereditary blindness, autosomal dominant optic atrophy (ADOA), is caused by the mutation of the mitochondrial protein Opa1 and the ensuing degeneration of retinal ganglion cells. Previously we found that knockdown of OPA1 enhanced mitochondrial Ca2+ uptake (Fulop et al., 2011). Therefore we studied mitochondrial Ca2+ metabolism in fibroblasts obtained from members of an ADOA family. Gene sequencing revealed heterozygosity for a splice site mutation (c. 984+1G>A) in intron 9 of the OPA1 gene. ADOA cells showed a higher rate of apoptosis than control cells and their mitochondria displayed increased fragmentation when forced to oxidative metabolism. The ophthalmological parameters critical fusion frequency and ganglion cell–inner plexiform layer thickness were inversely correlated to the evoked mitochondrial Ca2+ signals. The present data indicate that enhanced mitochondrial Ca2+ uptake is a pathogenetic factor in the progress of ADOA.

We have previously described that silencing of the mitochondrial protein OPA1 enhances mitochondrial Ca(2+) signaling and aldosterone production in H295R adrenocortical cells. Since extramitochondrial OPA1 (emOPA1) was reported to facilitate cAMP-induced lipolysis, we hypothesized that emOPA1, via the enhanced hydrolysis of cholesterol esters, augments aldosterone production in H295R cells. A few OPA1 immunopositive spots were detected in ∼40% of the cells. In cell fractionation studies OPA1/COX IV (mitochondrial marker) ratio in the post-mitochondrial fractions was an order of magnitude higher than that in the mitochondrial fraction. The ratio of long to short OPA1 isoforms was lower in post-mitochondrial than in mitochondrial fractions. Knockdown of OPA1 failed to reduce db-cAMP-induced phosphorylation of hormone-sensitive lipase (HSL), Ca(2+) signaling and aldosterone secretion. In conclusion, OPA1 could be detected in the post-mitochondrial fractions, nevertheless, OPA1 did not interfere with the cAMP - PKA - HSL mediated activation of aldosterone secretion.

Mitochondrial Ca(2+) signal activates metabolism by boosting pyridine nucleotide reduction and ATP synthesis or, if Ca(2+) sequestration is supraphysiological, may even lead to apoptosis. Although the molecular background of mitochondrial Ca(2+) uptake has recently been elucidated, the regulation of Ca(2+) handling is still not properly clarified. In human adrenocortical H295R cells we found a regulatory mechanism involving p38 MAPK and novel-type PKC isoforms. Upon stimulation with angiotensin II (AII) these kinases are activated typically prior to the release of Ca(2+) and - most probably by reducing the Ca(2+) permeation through the outer mitochondrial membrane - attenuate mitochondrial Ca(2+) uptake in a feed-forward manner. The biologic significance of the kinase-mediated reduction of mitochondrial Ca(2+) signal is also reflected by the attenuation of AII-mediated aldosterone secretion. As another feed-forward mechanism, we found in HEK-293T and H295R cells that Ca(2+) signal evoked either by IP(3) or by voltage-gated influx is accompanied by a concomitant cytosolic Mg(2+) signal. In permeabilized HEK-293T cells Mg(2+) was found to be a potent inhibitor of mitochondrial Ca(2+) uptake in the physiologic [Mg(2+)] and [Ca(2+)] range. Thus, these inhibitory mechanisms may serve not only as protection against mitochondrial Ca(2+) overload and subsequent apoptosis but also have the potential to substantially alter physiological responses.

Forage sorghum species, comprising grain and silage sorghum (S orghum bicolor) and sudangrass (Sorghum sudanense ), are considered the most drought-tolerant field crops in Hungary (Siklósiné Rajki, 1997). Several features, such as its tropical origin, deep voluminous roots, and thick waxy leaves and stem, enable the plants to survive periods with insufficient rainfall (Wall and Ross, 1970). Owing to its large roots, the crop shows wide adaptability to soils with moderate or low fertility. Though sorghum is used mainly for forage in Hungary, it is a very important source of bioenergy in other countries. Hungary lies in the northern part of the European sorghum belt, so the emphasis in the breeding programme is to develop early or mid-early forage sorghum hybrids adapted to Hungarian climatic conditions and soil properties, to introduce them into commercial production and to make them available for farmers.