PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Essential elements”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 847 records · Page 47Linked to original sources

On the development and classification of diagnoses.

Nurses, as noted earlier, always have and are now using the five steps of the diagnosis process. This utilization is a valuable and essential element of a profession. On the other hand, conceptual analysis of the process suggests that all ten steps are necessary conditions for a natural history of nursing. Such a natural history would constitute a taxonomy of nursing diagnoses and would identify and codify essential concerns and associated nomenclatures which have been agreed upon by members of the profession. In turn, such an agreement would lead to a common universe of discourse for the clinicians, the students, the teachers, the administrators, and the researchers in nursing. A workable taxonomy would provide potential points of reference, purpose, and direction and would facilitate communication and collaboration in nursing practice, nursing education, and nursing research. Such a taxonomy would constitute a systematic ordering of the unique body of knowledge of nursing and would provide a foundation of level-one theory. On this basis could be built higher-level theories that are grounded in observable phenomena. This development, in turn, would create a bridge across the knowledge-practice gap and would allow more effective application of scientific knowledge to specific clinical patient-care and nursing problems. A workable taxonomy of nursing diagnoses would articulate areas of unique concern to nurses and nursing and would allow more unequivocal communication of the focus, limits, and nature of the realm of nursing to other professions, third-party payers, governmental agencies, and the public. Without the development of such a framework, nursing research will continue to flounder, nursing education will continue to lack articulation of ordered body of knowledge of nursing concerns and related cognitive and other competencies, and nursing practice will continue to drift toward the use of medical terminology and to focus on dependent and technical nursing functions and the extension of the role of the nurse in the domain of medicine. In short, the lack of a sound taxonomy of nursing diagnoses endangers the realm of independent functions of nursing--its care, comfort, and compassion for the person who suffers from illness, and its focus on increased patient self-help ability, self-determination, and health promotion.

Classification↗

A new U6 small nuclear ribonucleoprotein-specific protein conserved between cis- and trans-splicing systems.

Spliceosomal U6 small nuclear RNA (snRNA) plays a central role in the pre-mRNA splicing mechanism and is highly conserved throughout evolution. Previously, a sequence element essential for both capping and cytoplasmic-nuclear transport of U6 snRNA was mapped in the 5'-terminal domain of U6 snRNA. We have identified a protein in cytoplasmic extracts of mammalian and Trypanosoma brucei cells that binds specifically to this U6 snRNA element. Competition studies with mutant and heterologous RNAs demonstrated the conserved binding specificity of the mammalian and trypanosomal proteins. The in vitro capping analysis of mutant U6 snRNAs indicated that protein binding is required but not sufficient for capping of U6 snRNA by a gamma-monomethyl phosphate. Through RNA affinity purification of mammalian small nuclear ribonucleoproteins (snRNPs), we detected this protein also in nuclear extract as a new specific component of the U6 snRNP but surprisingly not of the U4/U6 or the U4/U5/U6 multi-snRNP. These results suggest that the U6-specific protein is involved in U6 snRNA maturation and transport and may therefore be functionally related to the Sm proteins of the other spliceosomal snRNPs.

Animals↗

[Myocardial infarct promoting type A behavior--an attempt to modify stress-inducing behavior].

To change some crucial elements of coronary-prone behaviour in cardiac patients is considered an important task of behaviour medicine, to reduce physico-chemical and, in particular, psychosocial "risk factors". The experimental study presented had examined whether the type A behaviour pattern, defined as the essential element of coronary-prone behaviour for its latent provocation of stress reactions, can be positively modified through behaviour therapy-focussed treatment within a clinical setting. A total of 91 persons, i.e. 49 recent-MI patients from an inpatient rehabilitation programme and 42 clients of a smoker counselling centre, were examined to identify type A or type B behaviour patterns (Rosenman u. Friedman, 1964). Of 39 type A post-MI patients, 13 (randomly selected) subjects were included in the "trial group" (VG), and participated, within a 4-8 week inpatient rehabilitation programme, in psychological training of stress management, relaxation, and self-control techniques; 3 patients denied participation; the remaining 23 type A post-MI patients, and the 20 type A smoker counselling clients, served as control group KG (A) and KG (B), who did not receive psychological training. Psychological and physiological parameters were assessed at the beginning (t1), the end (t2), as well as 3 and 6 months (t3 and t4) following completion of the psychological training. The results obtained confirm that the MI group includes significantly more type A persons (80 percent) than the cardiologically inconspicious control group of smokers (48 percent). Analysis of the data obtained at the various measurement points show that, as opposed to KG (A) and KG (B), significant improvements have in fact occurred in the trial group, such as reduced mental and psychovegetative stress reactions, which persisted even 3 months after programme completion.(ABSTRACT TRUNCATED AT 250 WORDS)

Arousal↗

Transcription signals in embryonic Xenopus laevis U1 RNA genes.

A genomic clone of the most abundant U1 RNA genes from Xenopus laevis was isolated from erythrocyte DNA and sequenced. Two different U1 RNA genes, U1A and U1B, are encoded in an HindIII 1.5-kb fragment and both are expressed after microinjection in Xenopus oocytes. Deletions and site-directed mutagenesis of the clones revealed two promoter elements in the U1B gene; one, located 250-220 nucleotides upstream from the 5' terminus of mature U1 RNA, functions as an activator, yielding a 10-fold promotion of transcription; the other, located 60-50 nucleotides upstream of the cap site, functions as an essential element for promotion of transcription. The U1A gene contained only the latter element in the cloned fragment. Homologous sequences can be identified in several U RNA genes of X. laevis.

Animals↗

Elements of successful restraint and seclusion reduction programs and their application in a large, urban, state psychiatric hospital.

In recent years, there has been a strong desire on the part of inpatient psychiatric programs to reduce the use of seclusion and mechanical restraint. There is a consensus among those who have published descriptions of successfully implemented restraint and seclusion reduction programs that the essential elements of such programs are high level administrative endorsement, participation by recipients of mental health services, culture change, training, data analysis, and individualized treatment. This article describes these elements and their application in a successful restraint reduction program at Creedmoor Psychiatric Center, a large, urban, state-operated psychiatric hospital that reduced its combined restraint and seclusion rate by 67% over a period of 2 years.

Journal Article↗

A U-snRNA gene-specific upstream element and a -30 'TATA box' are required for transcription of the U2 snRNA gene of Arabidopsis thaliana.

The U2 and U5 snRNA genes of Arabidopsis thaliana contain in their promoter regions two elements with conserved sequence and position. To test the significance of this conservation we have made a construction in which the promoter of the U2 RNA gene is replaced by the synthetic 98 bp long sequence containing the two conserved elements: an upstream sequence element, GTCCCACATCG (USE, pos. -78 to -68), and a TATA-like sequence TATAAATA (-33 to -26), positioned approximately three helical turns apart, as in the wild-type promoter. This synthetic promoter efficiently drove transcription of the U2 gene in transfected protoplasts of Nicotiana plumbaginifolia. The importance of the individual elements and of their position within the promoter was investigated. Deletion of the USE, change of its orientation, and some single point mutations all decreased transcription 10- to 20-fold, and replacement of the TATA-like element by an unrelated sequence inactivated the promoter. Mutants in which the spacing between the USE and TATAAATA was changed were less active but no correlation was observed between promoter activity and insertion of either odd or even numbers of half helical turns. Insertion of a spacer between TATAAATA and the cap site resulted in accumulation of U2 RNA with an extended 5' end, indicating that the TATAAATA element is responsible for selection of the initiation site. The data indicate that the promoters of RNA polymerase II-specific U-snRNA genes in higher plants differ from their animal counter-parts and also from plant mRNA gene promoters. They contain two essential elements, an USE, an element found only in U-snRNA genes, and a TATA element which is indistinguishable from the TATA boxes of mRNA-coding genes.

Base Sequence↗

Specificity of damage recognition and catalysis of DNA repair.

A common feature of DNA repair enzymes is their ability to recognize the damage independently of sequence in which they are found. The presence of a flipped out base inserted into the protein in several DNA-enzyme complexes suggests a contribution to enzyme specificity. Molecular simulations of damaged DNA indicate that the damage produces changes in DNA structure and changes the dynamics of DNA bending. The reduced bending force constant can be used by the enzyme to induce DNA bending and facilitate base flipping. We show that a thymine dimer (TD) containing DNA requires less energy to bend, lowering the barrier for base flipping. On the other hand, bending in DNA with U-G mismatch is affected only by a small amount and flipping is not enhanced significantly. T4 endonuclease V (endoV), which recognizes TD, utilizes the reduced barrier for flipping as a specific recognition element. In uracil DNA glycosylase (UDG), which recognizes U-G mismatches, base flipping is not enhanced and recognition is encoded in a highly specific binding pocket for the flipped base. Simulations of UDG and endoV in complex with damaged DNA provide insight into the essential elements of the catalytic mechanism. Calculations of pKas of active site residues in endoV and endoV-DNA complex show that the pKa, of the N-terminus is reduced from 8.01 to 6.52 while that of Glu-23 increases from 1.52 to 7.82. Thus, the key catalytic residues are in their neutral form. The simulations also show that Glu-23 is also H-bonded to O4' of the 5'-TD enhancing the nucleophilic attack on Cl and that Arg-26 enhances the hydrolysis by electrostatic stabilization but does not participate in proton transfer. In the enzyme-substrate complex of UDG, the role of electrostatic stabilization is played by His-268, whose pKa increases to 7.1 from 4.9 in the free enzyme. The pKa of Asp-145, the other important catalytic residue, remains around 4.2 in the free enzyme and in the complex. Thus, it can not act as a proton acceptor. In the complex the 3'-phosphate of uracil is stabilized next to Asp-145 by two bridging water molecules. Such a configuration activates one water molecule to act as a proton acceptor to produce a stabilizing hydronium ion and the other as a proton donor to produce the nucleophilic hydroxide. It appears that DNA glycosylases share commonalties in recognition of damage but differ in their catalytic mechanisms.

Base Pair Mismatch↗

Regulation of splicing is responsible for the expression of the muscle-specific 2a isoform of the sarco/endoplasmic-reticulum Ca(2+)-ATPase.

Tissue-specific alternative processing of sarco/endoplasmic reticulum Ca(2+)-ATPase 2 (SERCA2) transcripts generates functionally different Ca2+ pump isoforms in muscle compared with non-muscle tissues. In non-muscle cells, the SERCA2 pre-mRNA can be polyadenylated at a site located between the donor and acceptor splice site of an intron which is only removed in muscle tissues. To define the cis-active elements involved in differential processing, we constructed a minigene (pCM beta SERCA2) containing the 3' end of the SERCA2 gene. When stably transfected into a myogenic cell line, minigene transcripts were differentially processed depending on the differentiation state of the cells. This proves that the essential elements required for regulated processing are present in the construct. Furthermore, co-transfection of the pCM beta SERCA2 minigene and a myogenin expression vector in a fibroblast cell line induced muscle-specific splicing of transcripts from pCM beta SERCA2. This shows that trans-acting factor(s) responsible for muscle-specific processing can be induced by one of the important regulatory genes of muscle differentiation. Inactivation of the non-muscle poly(A) site did not induce splicing in non-muscle cells. This excludes a simple competition model between splicing and polyadenylation, but it is consistent with splicing being very inefficient in non-muscle cells. Moreover, splicing could be induced in non-muscle cells by optimizing the muscle-specific donor splice site and/or by shortening the intron length. We therefore propose that expression of the muscle-specific SERCA2a isoform is the result of activation of an otherwise inefficient splicing process.

Animals↗

Do the levels of selected metals differ significantly between the roots of carious and non-carious teeth?

Since the metals deposited in teeth during formation and mineralization processes are to a large extent retained, human teeth receive a considerable attention as the indicators of the heavy metal exposure. The use of permanent teeth is limited because the extraction of healthy permanent teeth just for this purpose is hardly acceptable. As the issue of the loss of elements from a carious lesion in the coronal part of a tooth remains controversial, the valuable material could only be the root of carious and fractured permanent teeth. However, to ensure the validity of the results, it should be ascertained that the levels of certain toxic and essential elements do not differ significantly between the roots of non-carious and carious teeth, and therefore this is the aim of this project. The levels of cadmium, chromium, copper, iron, manganese, lead, zinc, potassium, sodium, calcium and magnesium were determined in the roots of 344 permanent teeth (189 carious and 155 caries-free teeth) from the residents of Ruda Slaska, Poland, aged 18 to 34. No statistically significant difference between the concentration of these metals in the roots of non-carious and carious teeth was found. This finding applies to both the general population and after the grouping by donor's gender and tooth type. The concentration of lead, iron, calcium and manganese in the roots of non-carious and carious teeth exhibited dependence upon tooth type, as well as the concentration of potassium in the roots of carious teeth. Since the mineral composition of the roots of permanent teeth is similar for the non-carious, as well as the carious teeth, they can be indiscriminately selected for the tests required by a research project, as they will produce the comparable results. However, in the case of lead, iron, calcium, potassium and manganese, the comparison should be made after grouping by tooth type.

Adult↗

Shamanism as a healing paradigm for complementary therapy.

Any healing process--whether recovery from infection, physical trauma, or psychological distress--must entail the stimulation and direction of the body's own restorative functions. In former times these functions were called the vis mediatrix naturae. Arguably best articulated within traditional Chinese medicine (e.g. Reid 1993), many complementary therapies have identified this principle. The immune system is implicated in the operation of these healing processes, and immune system functions are modulated by both internal and external variables. External variables include the nature of the infection or trauma. Internal variables include the meaning of the illness to the patient or the patient's imagery surrounding the illness. It follows that any modulation of internal variables that increases immune function will therefore be highly beneficial in the healing process. Sometimes such modulation happens spontaneously, when it may be referred to as the placebo effect, or a good bedside manner, or spontaneous remission. Sometimes such modulation may be brought about intentionally either by the patient or by a therapist or healer. One body of technique for such modulation is shamanism, which pays particular attention to bridging the internal world of the patient to the external world where the problem originates. Shamanic practice is specifically focused on this healing task, and has its own toolkit of techniques for the modification of consciousness, the manipulation of imagery and meaning, and the generation of a healing milieu and therapeutic images from its mythic content. Early concerns about the mental health of shamanic practitioners are now thoroughly resolved (e.g. Stephen & Suryani 2000). Indeed, the relevance of shamanism to positive mental health is currently being explored (e.g. Money 1994, Singh 1999). Its relevance to social work (Voss et al. 1999) and to the near death experience (Green 1998) are also subjects of academic inquiry. The shamanic corpus exemplifies a healing paradigm that may also be used to understand the essential elements of healing, which underpin some established complementary therapies and some other healing modalities such as spiritual healing,'psychic' healing, spontaneous remission, and the placebo effect. The comparatively recent psychoneuroimmunological perspective appears to be congruent with and also to validate ancient shamanic healing technique. Both may share essential principles with complementary therapies and illuminate their essential healing processes.

Female↗

Down-regulation of early sea urchin histone H2A gene relies on cis regulative sequences located in the 5' and 3' regions and including the enhancer blocker sns.

The tandem repeated sea urchin alpha-histone genes are developmentally regulated by gene-specific promoter elements. Coordinate transcription of the five genes begins after meiotic maturation of the oocyte, continues through cleavage, and reaches its maximum at morula stage, after which these genes are shut off and maintained in a silenced state for the life cycle of the animal. Although cis regulative sequences affecting the timing and the level of expression of these genes have been characterized, much less is known about the mechanism of their repression. Here we report the results of a functional analysis that allowed the identification of the sequence elements needed for the silencing of the alpha-H2A gene at gastrula stage. We found that important negative regulative sequences are located in the 462 bp sns 5 fragment located in the 3' region. Remarkably, sns 5 contains the sns enhancer blocking element and the most 3' H2A codons. In addition, we made the striking observation that inhibition of the anti-enhancer activity of sns, by titration of the binding proteins in microinjected embryos, also affected the capability of sns 5 to down-regulate transgene expression at gastrula stage. A further sequence element essential for repression of the H2A gene was identified upstream of the enhancer, in the 5' region, and contains four GAGA repeats. Altogether these findings suggest that down-regulation of the alpha-H2A gene occurs by the functional interaction of the 5' and 3' cis sequence elements. These results demonstrate the involvement of a genomic insulator in the silencing of gene expression.

Animals↗

[Patient's consent to central venous catheterization].

The need to obtain a patient's consent for his health care is a principle set out in the Italian Constitution, which safeguards a person's right to health. Articles 13 and 32.2 confirm a person's freedom and the right to make free decisions about one's medical treatment. Nobody must be obliged to any medical procedure, unless as by law enacted. The obligation to inform patients is important during the contractual phase: consent is an essential element in the professional contract governing the relationship between a physician and a patient. The former is obligated to inform the latter about his medical intervention clearly and precisely, to enable the patient to decide freely whether to undergo a medical procedure. At this point, it is also essential to obtain a patient's consent for those treatments that although they are carried out in a correct and careful way, could damage a person's physical integrity. The failure to obtain consent could give rise to a burden of responsibility on behalf of the clinician. A central venous catheterization in hemodialysis (HD) is a common procedure performed during routine nephrological treatments. Our signed informed consent form prior to introducing a central venous catheter is thought to satisfy requirements provided for in current regulations to give correct information.

Catheterization, Central Venous↗

[Determination of eight trace elements in the flowers of Hylocereus undatus by FAAS].

The effects of different sample digestives for the flowers of Hylocereus undatus are compared. Eight trace elements in the flowers of Hylocereus undatus were determined by flame atomic absorption spectrophotometer. The result shows that the RSD and recovery are better if the flowers of Hylocereus undatus was digested with HNO3-HClO4 (5:1) mixed acid, and the flowers of Hylocereus undatus contains many essential elements among which the contents of Fe, Mn and Zn are higher than those of Ni and Cu. Co and Cd were not determined, but Pb was determined. The experimental results showed that the detection limits were all smaller than 0.086 microg x mL(-1), the RSDs (n = 8) all smaller than 8.37%, and the addition standard recovery (ASR) (n = 8) was 79.69%-118.6% for all elements.

Cactaceae↗

Regulation of polymerase II transcription by 7SK snRNA: two distinct RNA elements direct P-TEFb and HEXIM1 binding.

The positive transcription elongation factor b (P-TEFb), a complex of Cdk9 and cyclin T1/T2, stimulates transcription by phosphorylating RNA polymerase II. The 7SK small nuclear RNA, in cooperation with HEXIM1 protein, functions as a general polymerase II transcription regulator by sequestering P-TEFb into a large kinase-inactive 7SK/HEXIM1/P-TEFb complex. Here, determination and characterization of the functionally essential elements of human 7SK snRNA directing HEXIM1 and P-TEFb binding led to a new model for the assembly of the 7SK/HEXIM1/P-TEFb regulatory complex. We demonstrate that two structurally and functionally distinct protein binding elements located in the 5'- and 3'-terminal hairpins of 7SK support the in vivo recruitment of HEXIM1 and P-TEFb. Consistently, a minimal regulatory RNA composed of the 5' and 3' hairpins of 7SK can modulate polymerase II transcription in HeLa cells. HEXIM1 binds independently and specifically to the G24-C48/G60-C87 distal segment of the 5' hairpin of 7SK. Binding of HEXIM1 is a prerequisite for association of P-TEFb with the G302-C324 apical region of the 3' hairpin of 7SK that is highly reminiscent of the human immunodeficiency virus transactivation-responsive RNA.

3' Flanking Region↗

Training elements at different levels in the strategies for control of schistosomiasis.

Recently acquired comprehensive knowledge concerning the epidemiology of schistosomiasis has provided the background for the establishment of schistosomiasis control strategies. However, the planning, implementation, and maintenance of such control programmes requires sufficient numbers of well trained personnel at the local, district and central levels. Training of health personnel as well as motivation of the community are fundamental and essential elements in any schistosomiasis control programme. The training elements and approaches are discussed.

Allied Health Personnel↗

The importance of trace element speciation in biomedical science.

According to IUPAC terminology, trace element speciation reflects differences in chemical composition at multiple levels from nuclear and electronic structure to macromolecular complexation. In the medical sciences, all levels of composition are important in various circumstances, and each can affect the bioavailability, distribution, physiological function, toxicity, diagnostic utility, and therapeutic potential of an element. Here we discuss, with specific examples, three biological principles in the intimate relation between speciation and biological behavior: i) the kinetics of interconversion of species determines distribution within the organism, ii) speciation governs transport across various biological barriers, and iii) speciation can limit potentially undesirable interactions between physiologically essential elements. We will also describe differences in the speciation of iron in states of iron overload, to illustrate how speciation analysis can provide insight into cellular processes in human disease.

Alkylation↗

A simple signal element mediates transcription termination and mRNA 3' end formation in the DEG1 gene of Saccharomyces cerevisiae.

DEG1 is a weakly transcribed gene of Saccharomyces cerevisiae, closely associated with CEN6. We mapped its major poly(A) site only 24 nucleotides (nt) downstream of the stop codon, and only 26 nt upstream of the CDEI centromere element. The deletion of this 50 nt stretch completely abolishes formation of the mRNA 3' end. A shorter deletion of a 16 nt sequence in the 3'-untranslated region has the same effect on transcription termination and 3'-maturation function. A TATATA sequence within this 16 nt region is essential for both functions, while a TGTATA sequence has a weak compensating activity in 3' end maturation if the TATATA stretch is deleted. We assume that the 3' end formation signals of the DEG1 gene have this simple structure: a single essential element (TATATA, whether alone or with the few surrounding nucleotides), probably, but not necessarily, cooperating with the sequence at the poly(A) site. This simple structure differs from the emerging model for 3' end-processing signals in that (i) it is shorter: 24 nt long at the most, while the model suggests 39 nt; (ii) there is no element located downstream of the TATATA signal to position the poly(A) site; and (iii) unlike the other naturally occurring signals studied, no cooperation among multiple TATATA-like elements is observed. We found that the same TATATA sequence also directs transcription termination, irrespective of promoter strength, and presumably without the cooperation of a downstream polymerase II pausing site. Taken together, these findings support the hypothesis that the DEG1 3' end-forming signals are more condensed than in other yeast genes, probably because of their proximity to CEN6.

Base Sequence↗

p21(Cip1) and p27(Kip1) regulate cell cycle reentry after hypoxic stress but are not necessary for hypoxia-induced arrest.

We investigated the role of the cyclin-dependent kinase inhibitors p21(Cip1) and p27(Kip1) in cell cycle regulation during hypoxia and reoxygenation. While moderate hypoxia (1 or 0.1% oxygen) does not significantly impair bromodeoxyuridine incorporation, at very low oxygen tensions (0.01% oxygen) DNA replication is rapidly shut down in immortalized mouse embryo fibroblasts. This S-phase arrest is intact in fibroblasts lacking the cyclin kinase inhibitors p21(Cip1) and p27(Kip1), indicating that these molecules are not essential elements of the arrest pathway. Hypoxia-induced arrest is accompanied by dephosphorylation of pRb and inhibition of cyclin-dependent kinase 2, which results in part from inhibitory phosphorylation. Interestingly, cells lacking the retinoblastoma tumor suppressor protein also display arrest under hypoxia, suggesting that pRb is not an essential mediator of this response. Upon reoxygenation, DNA synthesis resumes by 3.5 h and reaches aerobic levels by 6 h. Cells lacking p21, however, resume DNA synthesis more rapidly upon reoxygenation than wild-type cells, suggesting that this inhibitor may play a role in preventing premature reentry into the cell cycle upon cessation of the hypoxic stress. While p27 null cells did not exhibit rapid reentry into the cell cycle, cells lacking both p21 and p27 entered S phase even more aggressively than those lacking p21 alone, revealing a possible secondary role for p27 in this response. Cdk2 activity is also restored more rapidly in the double-knockout cells when returned to normoxia. These studies reveal that restoration of DNA synthesis after hypoxic stress, but not the S phase arrest itself, is regulated by p21 and p27.

Animals↗