203 research outputs found
Quality Management in Hospitals: Does it Contribute to High Quality of Care?
Health policy-makers all around the world are facing the problem of ever-increasing costs in health care. In additio
n, the demand for high quality care is greater than ever. Since there is no indication that these trends will stop in the near future, the policy-makers have to find methods to mitigate these problems. One possible solution is the development of efficient quality strategies, including external quality assessment and improvement systems that focus on clinical effectiveness, the implementation of evidence based practice, patient safety programs and clinical audit. The aim of this paper is to identify and summ arize research studies which investigate the impact of different quality strategies and quality improvement methods on healthcare activities and outcomes, and to determine if these are effective clinical methods or not. For this reason, a systematic search was carried out in various databases. The literature suggests that having an external quality assessment system does contribute to better health care. However, most of the studies focus on
accreditation alone, and only three relatively low sample studies compare accreditation with ISO certification. Related to clinical-effectiveness, limited relevant results were found. Health policy-makers should consider different quality models as valid methods to provide high quality of care in hospitals, but they should also be aware that the clinical effectiveness of these has not yet been proven. More outcome-oriented, high sample studies should be carried out which compare one technique to another and find out if some of them could be implemented simultaneously
Biochemistry and Molecular Biology of Protein Phosphatase 1 in Drosophila melanogaster
Protein phosphatase 1 (PP1) activity was detected with exogenous and endogenous substrates in Drosophila extract. The catalytic subunit of PP1 was purified to apparent homogeneity. The physicochemical and biochemical properties of the preparation were very similar to those of rabbit PP1. One PP1 catalytic subunit was cloned from a Drosophila cDNA library with the aid of a rabbit PP1 cDNA and oligonucleotide probes. Subsequently, three additional genes encoding for highly similar PP1 isoforms in Drosophila were identified and cloned. It was found that the primary structure of PP1 had been very well conserved during evolution.
One of the isoforms, called PP1(87B), was predominantly expressed during all developmental stages of the insect. Several mutations affecting the PP1(87B) gene were characterized. Based on the phenotype of different mutant alleles, it was concluded that PP1(87B) was involved in viability, mitosis, interphase chromatin condensation and learning. Our results demonstrate that PP1(87B) has several functions which cannot be complemented by other PP1 isoforms of Drosophila
A protein foszfatáz Z szerepének felderítése a patogén gombák jelátviteli folyamataiban = Investigation of the function of protein phosphatase Z in the signal transduction of pathogenic fungi
A protein foszfatáz Z C. albicans ortológját kódoló gén, a CaPPZ1 klónozása és szekvenálása segítségével alátámasztottuk a humán patogén nagyfokú genetikai polimorfizmusát. Legalább 4 CaPPZ1 allélt azonosítottunk, és egy találtunk egy olyan hipervariábilis gén régiót, ami alkalmasnak bizonyult klinikai C. albicans izolátumok genotipizálása. In vitro mutagenézissel azonosítottuk a foszfatáz enzim aktivitását, illetve stabilitását biztosító aminosav oldalláncokat. Molekuláris genetikai módszerekkel bebizonyítottuk, hogy a CaPPZ1 szerepet játszik a gomba kation homeosztázisában, sejtfal bioszintézisében és membrán potenciáljának meghatározásában, valamint fontos a hifa növekedésben, és a patogén gomba fertőzőképességében. Megállapítottuk, hogy az A. fumigatus és az A. nidulans PPZ ortológok szerkezete konzerválódott, és a phzA, illetve a ppzA géntermékekről igazoltuk, hogy funkcionálisan helyettesítik a hiányzó PPZ enzimeket S. cerevisiae és S. pombe mutánsokban. Ennek ellenére a ppzA gén inaktiválása nem járt a várt fenotípusok változásokkal A. nidulansban, viszont érzékenységet okozott oxidálószer kezeléssel szemben. A genetikailag távol álló C. albicans és S. cerevisiae PPZ mutánsokkal történő összehasonlítás alapján arra a következtetésre jutottunk, hogy az PPZ enzimek részt vesznek a gombák oxidatív stressz válaszának modulálásában. Ily módon egy régóta ismert foszfatáz új funkcióját sikerült azonosítanunk. | By cloning and sequencing of the protein phosphatase Z (PPZ) coding CaPPZ1 gene we confirmed the high level of genetic polymorphism of the human pathogen C. albicans. We identified four different alleles of the gene and found a hypervariable DNA segment that was suitable for genotyping of clinical C. albicans isolates. With in vitro mutagenesis we pinpointed the amino acid residues that are important in the activity / stability of the phosphatase. With the aid of molecular genetics we revealed that CaPPZ1 was important in the cation homeostasis, cell wall integrity and membrane potential determination of the fungus. In addition to these general PPZ roles, we also found that CaPPZ1 was involved in the germ tube formation and in the virulence of the pathogen. By extending these results we predicted that the structures of the PPZ ortholog proteins were well conserved in A. fumigatus and A. nidulans, and demonstrated that the corresponding phzA and ppzA phosphatases behaved as the functional replacements of the yeast enzymes in S. cerevisiae and S. pombe deletion mutants. However, the inactivation of the PPZA gene did not result in the expected phenotypes in A. nidulans, but caused sensitivity to oxidative agents. By the comparison with the genetically distantly related C. albicans and S. cereveisiae PPZ mutants we proved that all of these PPZ phosphatases acted in the oxidative stress mediation of fungi. Thus, we identified a novel function for a long known enzyme family
Protein foszfatáz gének genetikai és molekuláris biológiai vizsgálata Drosophila melanogaster-ben = Genetic and molecular biological characterization of protein phosphatase genes in Drosophila melanogaster
A Drosophila melanogaster protein foszfatáz génjeinek tanulmányozásához genomikus adatbázis kutatás alapján több gént választottunk ki, amelyekre a közelben található P-elemek remobilizálásával mutációkat indukáltunk. Az indukált mutációk genetikai és molekuláris vizsgálatával következtettünk a gének funkciójára. Megállapítottuk, hogy a CG9238 gén mutációja sejtletalitást eredményez, és a glikogén-anyagcserét gátolja. A CG9238 genetikai kölcsönhatásban van az ovoD génnel. Kimutattuk, hogy a CG15031 gén terméke, amit PPYR1-nek neveztünk el, a PPY protein foszfatázzal stabil fehérje-fehérje komplexet alkot. A PPYR1-nek két izoformája van, amelyek expressziója eltérő szövetspecifitást mutat. A maternális eredetű izoforma a petekamrákban és a korai embriókban található, míg a zigótikus fehérje csak a herékben fordul elő. A PPYR1 eredendően rendezetlen szerkezetét és RNS-kötő képességét in vitro kísérletekben igazoltuk. A protein foszfatázokkal együtt a jelátviteli utakban résztvevő más géneket is megvizsgáltunk. Kimutattuk a Myo31DF szerepét a bal-jobb aszimmetria kialakulásában. Meghatároztuk egy 26S proteaszóma alegység lokalizációját és igazoltuk sejtmagba történő vándorlását. Megállapítottuk, hogy a filamin-240 fehérje gátolja a lamellociták differenciálódását. Kísérleteink igazolták a klasszikus és molekuláris genetikai módszerek együttes alkalmazásának előnyeit az ecetmuslica funkcionális genomikai kutatásában. | Based on genomic database searches we selected several Drosophila melanogaster protein phosphatase genes which have adjacent P-element insertion in order to induce loss of function mutations by the remobilization of the P-elements. Genetic and molecular biological approaches were used to study the functions of selected genes. We found that mutations in CG9238 gene result in cell autonomous lethality and the inhibition of glycogen metabolism. CG9238 interacts genetically with the ovoD gene. We discovered that the gene product of CG15031 (termed PPYR1) forms a stable protein-protein complex with the PPY protein phosphatase. PPYR1 has two different isoforms which exhibit different tissue specific expression patterns. The maternal isoform was detected in the egg chambers and early embryos, while the zygotic protein was located exclusively in the testes. The intrinsically unstructured nature and RNA binding capacity of PPYR1 was shown by in vitro experiments. In addition to the phosphatases we studied several genes which also play important roles in signal transduction. We proved the function of Myo31DF in the determination of left-right asymmetry. The localization of a 26S proteasome subunit was determined and its nuclear translocation was demonstrated. We described the inhibition of lamellocyte differentiation by filamine-240. Collectively, our results indicate the power of the combination of classical and molecular genetic approaches in the functional genetic studies of fruit flies
A foszfoprotein foszfatáz (PPP) enzimcsalád funkciójának vizsgálata Arabidopsis thalianaban = Functional study of the PPP family of phosphoprotein phosphatases in Arabidopsis thaliana
A szerin/treonin-specifikus foszfoprotein foszfatázok (PPP-k) minden eukariótában megtalálhatók, szabályozó szerepük azonban növényekben alig ismert. Az Arabidopsis genom 26 PPP katalitikus alegységet kódol, PP1- és PP2A-típusú, újtípusú és ismétlődő kelch motívumot tartalmazó foszfatázokat. Az Arabidopsis PPP-k funkciójának tanulmányozása céljából azonosítottuk a PP6At1(AtFyPP1), PP7, BSL3 és TOPP1(PP1) foszfatáz génekben T-DNS inszerciót hordozó mutánsokat. A pp6at1 mutáns csírázási és növekedési tesztekben hiperszenzitív volt nagy koncentrációjú sóra, ozmotikumokra és abszcizinsavra (ABA). Gyengült prolinfelhalmozó képessége és csökkent benne a prolin bioszintézisét reguláló, stressz-és ABA-indukált P5CS1 gén expressziója. A fentiek alapján a PP6At1 a környezeti stresszekre adott metabolikus válaszokat szabályozza. A pp7 mutáns hipokotilmegnyúlása kék fényben fokozott volt, vörös vagy fehér fényben nem. Úgy tűnik, hogy a PP7 a kék fény jelátvitelének fontos eleme. A BSL3, TOPP1 génekben, valamint a PP2A enzim PP2A-2 katalitikus alegységének és egy B" regulátor alegységének génjében levő inszerciókra (GABI-Kat vonalak) homozigóta növényeknek nem volt észlelhető fenotípusa. A PP2A hőstabil inhibitor fehérjékkel asszociálódhat. Azonosítottuk a SET Arabidopsis homológját (AtSET), amely a PP2A hatékony inhibitora. A rekombináns AtSET gátolja a hiszton H3 Ser-10 oldalláncának defoszforilációját, így szerepe lehet a transzkripció szabályozásában. | Serine/threonine specific phosphoprotein phosphatases (PPPs) are ubiquitous enzymes in all eukaryotes, but their regulatory functions are largely unknown in plants. The Arabidopsis genome encodes 26 catalytic subunits of PPPs related to PP1, PP2A, novel PPPs, and phosphatases with kelch-repeats. To study the function of Arabidopsis PPPs, we have identified T-DNA insertion mutants in the genes encoding PP6At1(AtFyPP1), PP7, BSL3, and TOPP1(PP1) phosphatases. The pp6at1 mutant was hypersensitive to high salt, osmotics and abscizic acid (ABA) as defined by germination and plant growth assays. Moreover, its impaired proline accumulation and reduced expression of the stress and ABA-induced P5CS1 gene, which controls proline biosynthesis, suggest that PP6At1 controls metabolic responses to environmental stress. The pp7 mutant showed increased hypocotyl elongation upon blue light irradiation, but not under red, or white light. Thus, PP7 appears to be an important factor in blue light signalling. Homozygous plants for the insertions in BSL3, TOPP1 and in genes encoding the PP2A-2 catalytic and a B" regulatory subunit of PP2A (GABI-Kat lines) had no observable phenotype. PP2A can be associated with heat stable inhibitory proteins.We identified the Arabidopsis homolog of SET (AtSET), which is a potent inhibitor of PP2A. Recombinant AtSet inhibits the dephosphorylation of Ser-10 in histone H3 and might be involved in the regulation of transcription
Molecular cloning and chromosomal localization of a novel Drosophila protein phosphatase
AbstractA 1.0 kilobase cDNA coding for the complete amino acid sequence of a putative protein phosphatase (314 amino acid residues, molecular mass 36 kDa) has been isolated from a Drosophila head cDNA library. The cDNA hybridises to a single site on the right arm of the second chromosome at cytological position 55A1–3. The deduced sequence of the protein, designated protein phosphatase-Y, is homologous to the catalytic subunits of Drosophila and rabbit protein phosphatase- 1α (64 and 59% identity, respectively) and rabbit protein phosphatase-2A (39% identity). These and other comparisons demonstrate that this novel enzyme is not the Drosophila counterpart of mammalian protein phosphatases 1, 2A, 2B, 2C or X
Separation of 1–23-kb complementary DNA strands by urea–agarose gel electrophoresis
Double-stranded (ds), as well as denatured, single-stranded (ss) DNA samples can be analyzed on urea–agarose gels. Here we report that after denaturation by heat in the presence of 8 M urea, the two strands of the same ds DNA fragment of ∼1–20-kb size migrate differently in 1 M urea containing agarose gels. The two strands are readily distinguished on Southern blots by ss-specific probes. The different migration of the two strands could be attributed to their different, base composition-dependent conformation impinging on the electrophoretic mobility of the ss molecules. This phenomenon can be exploited for the efficient preparation of strand-specific probes and for the separation of the complementary DNA strands for subsequent analysis, offering a new tool for various cell biological research areas
Analysis of Two Putative Candida albicans Phosphopantothenoylcysteine Decarboxylase / Protein Phosphatase Z Regulatory Subunits Reveals an Unexpected Distribution of Functional Roles
Analysis of Two Putative Candida albicans Phosphopantothenoylcysteine Decarboxylase / Protein Phosphatase Z Regulatory Subunits Reveals an Unexpected Distribution of Functional Roles
Protein phosphatase Z (Ppz) is a fungus specific enzyme that regulates cell wall integrity, cation homeostasis and oxidative stress response. Work on Saccharomyces cerevisiae has shown that the enzyme is inhibited by Hal3/Vhs3 moonlighting proteins that together with Cab3 constitute the essential phosphopantothenoylcysteine decarboxylase (PPCDC) enzyme. In Candida albicans CaPpz1 is also involved in the morphological changes and infectiveness of this opportunistic human pathogen. To reveal the CaPpz1 regulatory context we searched the C. albicans database and identified two genes that, based on the structure of their S. cerevisiae counterparts, were termed CaHal3 and CaCab3. By pull down analysis and phosphatase assays we demonstrated that both of the bacterially expressed recombinant proteins were able to bind and inhibit CaPpz1 as well as its C-terminal catalytic domain (CaPpz1-Cter) with comparable efficiency. The binding and inhibition were always more pronounced with CaPpz1-Cter, indicating a protective effect against inhibition by the N-terminal domain in the full length protein. The functions of the C. albicans proteins were tested by their overexpression in S. cerevisiae. Contrary to expectations we found that only CaCab3 and not CaHal3 rescued the phenotypic traits that are related to phosphatase inhibition by ScHal3, such as tolerance to LiCl or hygromycin B, requirement for external K+ concentrations, or growth in a MAP kinase deficient slt2 background. On the other hand, both of the Candida proteins turned out to be essential PPCDC components and behaved as their S. cerevisiae counterparts: expression of CaCab3 and CaHal3 rescued the cab3 and hal3 vhs3 S. cerevisiae mutations, respectively. Thus, both CaHal3 and CaCab3 retained the PPCDC related functions and have the potential for CaPpz1 inhibition in vitro. The fact that only CaCab3 exhibits its phosphatase regulatory potential in vivo suggests that in C. albicans CaCab3, but not CaHal3, acts as a moonlighting protein
Investigation of the conditions affecting the joining of Hungarian hospitals to an accreditation programme: a crosssectional study
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