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PubMed2005

The "Essential Levels of Care" in Italy: when being explicit serves the devolution of powers.

The definition of an explicit health benefit package in Italy has gained importance because of devolution of powers from the national level to the regions. The set of services to be guaranteed by the public sector are defined at national level, while regions are accountable for their provision. This contribution discusses the entitlements and the decision criteria adopted by Italian policy-making bodies. Entitlements to services are clearly defined for few sectors (mainly outpatient specialist care); for hospital care the benefit catalogue is vague. The definition of the health benefit package in Italy is an essential element of the relationship between the central government and the regions. It is argued that adequate monitoring systems and accountability procedures are still needed to make the essential levels of care an effective pivotal element of the Italian National Health Service.

Financing, Government↗

PubMed2004

Arsenic and other elements in hair, nails, and skin-scales of arsenic victims in West Bengal, India.

For the first time, biological tissues (hair, nails, and skin-scales) of arsenic victims from an arsenic affected area of West Bengal (WB), India were analyzed for trace elements. Analysis was carried out by inductively coupled plasma-mass spectrometry (ICP-MS) for 10 elements (As, Se, Hg, Zn, Pb, Ni, Cd, Mn, Cu, and Fe). A microwave digester was used for digestion of the tissue samples. To validate the method, certified reference materials--human hair (GBW 07601) and bovine muscle (CRM 8414)--were analyzed for all elements. The W test was used to study the normal/log normal distribution for each element in the tissue samples. For hair (n=44) and nails (n=33), all elements show log-normal distribution. For skin-scale samples (n=11), data are not sufficient to provide the information about the trend. Geometric mean, standard error, and range for each element were presented and compared with literature values for other populations. This study reveals the higher levels of toxic elements As, Mn, Pb, and Ni in the tissue samples compared with available values in the literature. The elevated levels of these toxic metals in the tissues may be due to exposure of these elements through drinking water and food. The correlations of Mn and Ni with other essential elements, e.g. Fe, Cu, Zn, suggest that Mn and Ni may substitute for those elements in hair, nails, and skin-scales. However, correlation represents the relation between two elements only and does not take into consideration of the presence of other elements. Principle component analysis was applied to explain the behavior among the elements present in hair and nails. This study reveals that in the arsenic-affected areas of WB, the concentrations of other toxic elements in drinking water and foodstuff should be monitored to evaluate the arsenic poisoning.

Arsenic↗

PubMed1990

Trace minerals in the nutrition of children.

Trace elements perform important functions in growth and development. However, little information exists about their dietary requirements during the demanding period of infancy. Opportunities to add to knowledge of the physiologic significance and dietary adequacy of trace elements in human nutrition are provided by recent analytic advances. Specific, sensitive, and reliable methods for the detection of trace element imbalances are sorely needed. Although several factors influence the dietary needs of these essential elements, the basis for establishing dietary needs in infants is hindered by the death of studies that have assessed their bioavailability in this age group. Thus until it has been conclusively shown otherwise, the physiologic response to human milk is used as the standard for infant feeding practices. This review is limited primarily to the physiologic significance and bioavailability of zinc, copper, manganese, molybdenum, chromium, fluoride, and selenium. The space devoted to each trace element is not meant to represent the element's importance but, rather, to reflect some of the present understanding of its metabolism and utilization.

Biological Availability↗

PubMed2001

Screening in Austria: the cases of mammography, PSA testing, and routine use of ultrasound in pregnancy.

OBJECTIVE: To study cases of screening in Austria to learn about national strategies to handle the health policy challenge of early detection of widespread diseases and about the outcome of those strategies. The article describes three healthcare interventions (mammography, PSA testing, and routine use of ultrasound in pregnancy) and the instruments of Austrian health policy that are used-with or without explicit intention-to enforce or to control the widespread use of (early) diagnoses. METHODS: Data and information collection on healthcare services, their accessibility, rate of use, expert consensus, and official regulations. For all three case studies, expert interviews were carried out with main actors. RESULTS: Risk-group screening is not a priority in Austrian federal health policy. Although health promotion and prevention is a national task, examinations for early detection of specific diseases (i.e., carcinoma) are left to the health insurance funds, which delegate the decision to offer early diagnoses to their contracted physicians. In this opportunistic screening, general practitioners or specialists are encouraged by their health insurance funds or motivated by professional guidelines to offer certain examinations. CONCLUSIONS: Screening is a coordinated effort to acquire a grasp of a common disease at an early stage in a specified population. To achieve this objective, a culture of coordination and centralization has to be implemented. The collection of data is an essential element in coordination of decentralized medical interventions as much as quality control is an essential task in looking at and comparing the outcome of interventions. In the three case studies, neither of these two essential criteria were met. Evaluations and scientific evidence on the effectiveness of interventions were not used.

Adult↗

PubMed2003

Characterization of Saccharomyces cerevisiae Ras1p and chimaeric constructs of Ras proteins reveals the hypervariable region and farnesylation as critical elements in the adenylyl cyclase signaling pathway.

Ras1p and Ras2p, from Saccharomyces cerevisiae, are GTP-binding proteins that are essential elements in the signaling cascade leading to the activation of adenylyl cyclase. To overcome proteolytic activities that have hampered biochemical studies of Ras1p so far, its gene was genetically modified after which full-length Ras1p could be obtained. The interaction of farnesylated and unprenylated Ras1p with guanine nucleotides, guanine nucleotide exchange factors, GTPase activating proteins, and adenylyl cyclase was compared to Ras2p and human Ha-Ras interactions. Farnesylation of Ras proteins was demonstrated to be a prerequisite for membrane-bound guanine nucleotide exchange factor dependent formation of Ras-GTP complexes, and for efficient Ras-mediated adenylyl cyclase activation. To relate observed functional deviations with sequence differences between Ras1p and Ras2p, which reside almost exclusively within the hypervariable region, truncated versions and chimaeras of the Ras proteins were made. The characteristics of these constructs point to the presence of the hypervariable region of yeast Ras proteins for an efficient activation of adenylyl cyclase. The importance of the latter was confirmed as inhibition of the activation of adenylyl cyclase by an isolated farnesylated hypervariable region of Ras2p could be shown. This strongly suggests that the hypervariable region of Ras proteins can interact directly with adenylyl cyclase.

Adenylyl Cyclase Inhibitors↗

PubMed1990

RNA-polymerase specificity of transcription of Arabidopsis U snRNA genes determined by promoter element spacing.

Although most eukaryotic genes known to be transcribed by RNA polymerase III have intragenic promoter elements, some are similar to genes transcribed by RNA polymerase II in that they have upstream promoters (reviewed in refs 1-4). Transcription of the vertebrate U6 and 7SK RNA genes by RNA polymerase III depends exclusively upon upstream signals, some of which are indistinguishable from the elements essential for polymerase II-specific genes. In the plant Arabidopsis thaliana the promoter elements for the U6 and U2 small nuclear RNA genes, transcribed by RNA polymerases III and II respectively, are identical, comprising a -30 TATA box and an upstream element specific for small nuclear RNA genes. The distance between these elements differs, however. Here we report evidence that this separation is crucial in determining whether the genes are transcribed by polymerase II or III.

Base Sequence↗

PubMed2005

Identification of cis-elements that regulate gene expression during initiation of axillary bud outgrowth in Arabidopsis.

Growth regulation associated with dormancy is an essential element in plant life cycles. To reveal regulatory mechanisms of bud outgrowth, we analyzed transcriptomes of axillary shoots before and after main stem decapitation in Arabidopsis (Arabidopsis thaliana). We searched for any enriched motifs among the upstream regions of up-regulated and down-regulated genes after decapitation. The promoters of down-regulated genes were enriched for TTATCC motifs that resemble the sugar-repressive element, whereas the promoters of up-regulated genes were enriched for GGCCCAWW and AAACCCTA, designated Up1 and Up2, respectively. Transgenic plants harboring a reporter gene driven by a tandem repeat of the elements were produced to analyze their function in vivo. Sugar-repressive element-mediated gene expression was down-regulated by the application of sugars but was unaffected after decapitation. In contrast, expression driven by the repeat containing both Up1 and Up2 was up-regulated after decapitation, although the Up1 or Up2 repeat alone failed to induce reporter gene expression in axillary shoots. In addition, disruption of both Up1 and Up2 elements in a ribosomal protein gene abolished the decapitation-induced expression. Ontological analysis demonstrated that up-regulated genes with Up elements were disproportionately predicted to function in protein synthesis and cell cycle. Up1 is similar to an element known to be a potential target for TCP (TEOSINTE BRANCHED1, CYCLOIDEA, PCFs family) transcription factor(s), which regulate expression of cell cycle-related and ribosomal protein genes. Our data indicate that Up1-mediated transcription of protein synthesis and cell cycle genes is an important regulatory step during the initiation of axillary shoot outgrowth induced by decapitation.

Arabidopsis↗

PubMed2002

[Maturation, separation and social integration. Some developmental psychology aspects of childhood sports].

The unfolding of motorical and social experiences with one's own body is a core element of ego-development and identity in childhood and adolescence. This paper describes essential elements of this process in different age stages. Especially in adolescence, the maturational and separational development are determined by the complex interaction between integration into the peer group and separation from adults, between search for appreciation and oppositional tendencies. On the one hand sport plays an important role for many adolescents during this process. On the other hand adolescent conflicts have a great impact on practising sport. These considerations are illustrated by two case vignettes.

Adolescent↗

PubMed2003

[Hepcidin--a peptide regulating the quantity and distribution of iron in the body in healthy and disease states].

Iron is an essential element and its amount and balance must be precisely regulated. Iron intestinal absorption is essential for the iron balance; however, the precise mechanism of its regulation remains unknown. Antimicrobial peptide hepcidin, produced in the liver, is considered as a key regulator of iron absorption and kinetics in the organism. Its expression increases in response to the iron overload. Hepcidin decreases iron absorption in the duodenum and causes its sequestration in macrophages. Apart from the iron, inflammation increases hepcidin expression in the liver, and hepcidin is considered to be acute phase protein. Hepcidin is not only the physiological regulator of iron kinetics but is supposed to be a part of the pathogenetic mechanism of anaemia accompanying chronic diseases and its relationship to the hereditary hemochromatosis is also studied.

Acute-Phase Proteins↗

PubMed2001

In vitro activity of ceftizoxime and ceftazidime in presence of essential and trace elements.

The research work comprises of the study of the changes in antimicrobial activity of ceftizoxime and ceftazidime after interaction with essential and trace elements. The minimum inhibitory concentration (MIC) was observed and thereafter compared with the standard MIC's of the respective drug by agar dilution method against both Gram positive and Gram-negative organisms so as to evaluate changes in antimicrobiological activity of the standard cephalosporins after metal interactions. It was observed that these metal elements that are essential for our body, either present within the body or coadminstered with vitamins markedly influence the MIC's of antibiotics by producing synergism or antagonism.

Journal Article↗

PubMed2003

Regulation of cytosolic phosphoenolpyruvate carboxykinase gene expression in adipocytes.

Cytosolic phosphoenolpyruvate carboxykinase (EC 4.1.1.32; PEPCK-C) catalyzes the critical regulated step in adipocyte glyceroneogenesis. Numerous studies have shown that hormones and nutrients regulate PEPCK-C at the transcriptional level. We identified two upstream cis-acting DNA elements, gAF1/PCK1 and PCK2, that control adipocyte specific transcription of the PEPCK-C gene (Pck1). Both elements are direct repeat hexanucleotides separated by 1 bp (DR1 elements; variations of the sequence AGGTCAnAGGTCA). PCK2 is located 1 kbp upstream and is the essential element of an adipocyte specific enhancer. It is a peroxisome proliferator activated receptor gamma response element (PPRE) and directs the activation of the PEPCK-C gene during adipogenesis. In addition, it is a thiazolidinedione response element in mature adipocytes. In contrast, gAF1/PCK1, centered 445 bp upstream, is a pleiotropic element that mediates tissue specific glucocorticoid action-repression in adipocytes and induction in hepatocytes. It is a negative response element for PPARgamma, RXRalpha, COUP-TFII, and several unidentified proteins in some cell types, and a positive element for COUP-TFI and HNF4 in other cells type. The purpose of this presentation is to review the discovery and characterization of these two elements in adipocytes and describe how our work has contributed to understanding the mechanisms that control adipocyte glyceroneogenesis.

Adipocytes↗

PubMed1979

Trace elements in soils and crops.

To demonstrate the total amounts to be expected in soils, the ranges of contents of some 60 trace elements in ten representative Scottish arable surface soils are compared with ranges in soil-forming rocks and with crustal averages. It is, however, the amounts potentially available to plants rather than the total contents that are biologically significant. In temperate climates, trace element mobilization is greatest when weathering takes place under conditions of impeded pedological drainage, leading to the formation of gleyed soils. Mobilized trace elements occur in arable surface soils largely in adsorbed and chelated forms, which are available to plants to a greater or smaller extent depending on the prevailing soil parameters and on the element in question. Different species take up different amounts of trace elements: the proportions in the various plant parts vary with the element and the stage of growth. Information is required about the mobilization and uptake of many elements about which little is at present known but which may affect the functions of essential elements through inter-element interactions. Systematic soil surveys in which soils are mapped by associations related to parent material, with their series related to genetic soil types, provide a useful countrywide guide to trace element status.

Agriculture↗

PubMed1994

Behavior therapy for obsessive compulsive disorder.

Exposure in vivo and ritual or response prevention are the essential elements of behavior therapy for obsessive compulsive disorder. Naturalistic behavior therapy helped a fortunate few before the effective elements of behavior therapy were identified and systematically applied. Homework exposure and response prevention are essential and therapist accompaniment is seldom necessary. Homework sessions are planned by patient and clinician and written records facilitate treatment modifications during homework sessions. About a quarter of patients refuse behavior therapy, but 90% of the remainder achieve worthwhile gains with exposure and response prevention. Limited availability of behavior therapy is a substantial public health problem.

Behavior Therapy↗

PubMed1984

[Molecular interactions of membrane proteins and erythrocyte deformability].

The structural and functional properties of the erythrocytic membrane constitute one of the essential elements of the red cell deformability. They intervene not only in the flexibility of the membrane, but also in the surface/volume relation and, through transmembrane exchanges, in the internal viscosity of the red cells. These properties depend essentially on the molecular composition of the elements which constitute the membrane, and on their interactions. The shape of the red cell and the flexibility of its membrane depend, to a great extent, on the membrane skeleton, whose main components are spectrin, actin, and protein 4.1. The spectrin basic molecule is a heterodimer, but there occur interactions between dimers in vitro as well as in vivo, which lead to the formation of tetrameric and oligomeric structures of higher complexity. Disturbances of these interactions, such as have been observed in pathological cases, lead to an instability of the membrane, a loss of membrane fragments, and a decrease in the surface/volume relation, with, as a consequence, a reduced deformability. The stability of the membrane skeleton also depends on the interactions between spectrin and protein 4.1. These interactions occur through a binding site on the beta chain of spectrin apparently close to actin and calmodulin binding sites. Other interactions occur between the hydrophobic segment of spectrin and membrane lipids. The cytoskeleton is bound to the transmembrane proteins: by ankyrin to the internal segment of protein band 3, and by protein 4.1 to a glycoprotein named glycoconnectin. There seems to exist other, more direct, lower affinity bindings between the cytoskeleton on the one hand, and band 3 and glycophorin transmembrane proteins on the other hand, whose lateral mobilities are modified when the structure of the skeleton is perturbed. The membrane proteins, which are in contact with the cytosol, interact with the cytosolic proteins, in particular with certain enzymes involved in anaerobic glycolysis and with hemoglobin. The Hb-membrane interactions are complex and involve different binding types with various affinities, as through band 3 protein, phospholipids, and glycophorin. These bindings are particularly important in the case of certain abnormal hemoglobins such as S and C. If the existence of molecular interactions inside the membrane and their sites are fairly well known, the mechanisms which control or influence such interactions remain unknown.(ABSTRACT TRUNCATED AT 400 WORDS)

Actins↗

PubMed2001

Cadmium distribution and toxicity in tissues of small rodents.

The aim of the present paper is to discuss the accumulation and distribution of cadmium (Cd) in the various tissues of animals, the interactions of cadmium with other elements, and the damage to tissues caused by this metal. Cadmium is not physiologically or biochemically essential to an organism. It is absorbed via the gastrointestinal tract and lungs and accumulated in various tissues, mainly the kidneys and liver. The distribution of cadmium between various tissues depends on many endogenous and exogenous factors. Cadmium is bound to a low-molecular-weight protein, metallothionein (MT), and to high-molecular-weight proteins. This metal has a great affinity to thiol groups. Cadmium binds also to O- and N-containing ligands. The distribution of cadmium between organs differs markedly depending on the chemical form of administered Cd and the duration of exposure. Acute exposure results in a different distribution pattern throughout the body than does chronic exposure. Long-term exposure to high doses of cadmium may cause biochemical and functional changes in some critical organs. Cadmium can influence the absorption and distribution of essential elements and can replace them in enzymes. Metallothionein and glutathione play important roles in the transport of metals and in detoxification processes. Reported findings are mainly the results of experiments on laboratory animals. The lack of data concerning the localization of cadmium in various tissues of wild species is noticeable and there is a great need for such data.

Animals↗

PubMed2005

Nuclear lamins: building blocks of nuclear structure and function.

The cell nucleus is surrounded by a complex membranous envelope which separates the nucleoplasm from the cytoplasm. Unlike the cytoplasm, the nucleoplasm is not subdivided into membrane-bound compartments, which allows for the efficient segregation of a wide range of complex metabolic activities. In the absence of such membrane compartmentalization, the nucleus is faced with the daunting task of efficiently segregating and interconnecting an enormous array of critically important functions. These include the assembly of the large multi-component complexes or 'factories' involved in DNA replication and transcription. These structures are dynamic as they are assembled and disassembled both spatially and temporally at different times, implying the existence of an infrastructure or nucleoskeleton responsible for establishing and maintaining a complex nuclear architecture. There is increasing evidence that the nuclear lamins are essential elements of this nuclear infrastructure, and that their proper assembly and organization are required for numerous essential nuclear functions. Our goal has been to determine the roles of the nuclear lamins in vital nuclear processes including DNA replication and transcription. The hypothesis directing our investigations is that the lamins form a 3D network that courses throughout the nucleoplasm providing an infrastructure for the assembly and distribution of numerous multicomponent complexes involved in a wide range of nuclear functions.

Animals↗

PubMed1995

[Initiation of DNA replication in Streptomyces; organizational comparison of the oriC region in prokaryotic organisms].

DnaA protein and its binding sequence (DnaA-box) are two elements essential for the initiation of chromosomal replication in Escherichia coli and other bacteria. Recently these two elements have been found to be conserved in four Gram-positive bacteria (Bacillus subtilis, Micrococcus luteus, Mycoplasma capricolum and Streptomyces lividans). The structures of eubacterial DnaA-box regions and their locations on the chromosome and than functional aspects od DnaA protein have been compared.

Bacteria↗

PubMed1994

Recycling of trace elements required for humans in CELSS.

Recycle of complete nourishment necessary for human should be constructed in CELSS (Controlled Ecological Life Support Systems). Essential elements necessary for human support are categorized as major elements, semi-major elements and trace elements. Recently, trace elements have been identified from considerations of local diseases, food additive problems, pollution problems and adult diseases, consisting of Fe, Zn, Cu, Se, Co, F, Si, Mn, Cr, I, As, Mo, Ni, V, Sn, Li, Br, Cd, Pb, B. A review of the biogeochemical history of the earth's biosphere and the physiological nature of humans and plants explains some of the requirements. A possible route for intake of trace elements is considered that trace elements are dissolved in some chemical form in water, absorbed by plants through their roots and then transfered to human as foods. There may be a possibility that living things absorb some trace elements from atmosphere. Management and recycling of trace elements in CELSS is discussed.

Biological Evolution↗