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PubMed1984

Effect of metal chelators on excretion and tissue levels of essential trace elements.

The influence of one, three, and six doses of ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), and triethylenetetramine (TETA) on the urinary excretion of Ca, Cu, Fe, and Zn, and on their levels in liver, kidneys, heart, and serum in rats, was investigated to ascertain their suitability in amelioration of metal intoxication. While excretion of all the essential trace metals examined was enhanced significantly, the tissue and serum levels of some of them either increased or decreased after administration of the chelators. The results suggest depletion of some of the endogenous trace metals from the body and their intertissue redistribution following treatment with these chelating agents.

Animals↗

PubMed1998

In vitro mineral availability from digested tea: a rich dietary source of managanese.

Tea is potentially a rich source of some dietary metals and approximately 70 l are drunk per capita per year in the UK. In particular, tea may be an important source of Mn, since leaf tea contains 350-900 micrograms g-1 of this essential element. However, the leaching and bioavailability of Mn from tea have been little studied, so a recently developed in vitro assay was applied to compare the bioavailability of Mn from tea infusions with that of other major and trace essential elements. Analysis of tea infusions before digestion showed that 1.0 l contained 115% of the average daily dietary intake of Mn but < 6% of all other minerals. Samples of these infusions were incubated with human gastric juice (37 degrees C, 1 h) and some were then adjusted to pH 6.5 to simulate intestinal pH. All were centrifuged through ultrafilters with molecular mass cut-offs of 3, 10 and 30 kDa. The percentages of ultrafilterable (< 3 kDa) elements following simulated gastrointestinal digestion were (n = 3; mean +/- s) Ca 47.7 +/- 10.7, Cu 45.3 (n = 1), Fe < 5, Mg 66.4 +/- 1.6, Mn 39.8 +/- 11.4, K 40.3 +/- 2.2, Na 100.0 +/- 5.3 and Zn 33.7 +/- 1.1. Hence the ultrafilterability of elements showed the general trend M+ > M2+ > M3+, which is probably the inverse of the order of their strengths of binding to tea polyphenols. However, Mn was the only element found in significant dietary amounts in tea, and under simulated intestinal conditions was still 40% bioavailable.

Biological Availability↗

PubMed1995

A developmentally regulated chromosomal origin of replication uses essential transcription elements.

Only one of the two chromosomes in the asymmetric Caulobacter predivisional cell initiates replication in the progeny cells. Transcription from a strong promoter within the origin occurs uniquely from the replication-competent chromosome at the stalked pole of the predivisional cell. This regulated promoter has an unusual sequence organization, and transcription from this promoter is essential for regulated (cell type-specific) replication. Our analysis defines a new class of bacterial origins and suggests a coupling between transcription and replication that is consistent with the phylogenetic relationship of Caulobacter to the ancestral mitochondrion.

Base Sequence↗

PubMed2005

The American Board of Radiology Maintenance of Certification (MOC) Program in Radiologic Physics.

Maintenance of Certification (MOC) recognizes that in addition to medical knowledge, several essential elements involved in delivering quality care must be developed and maintained throughout one's career. The MOC process is designed to facilitate and document the professional development of each diplomate of The American Board of Radiology (ABR) through its focus on the essential elements of quality care in Diagnostic Radiology and its subspecialties, and in the specialties of Radiation Oncology and Radiologic Physics. The initial elements of the ABR-MOC have been developed in accord with guidelines of The American Board of Medical Specialties. All diplomates with a ten-year, time-limited primary certificate in Diagnostic Radiologic Physics, Therapeutic Radiologic Physics, or Medical Nuclear Physics who wish to maintain certification must successfully complete the requirements of the appropriate ABR-MOC program for their specialty. Holders of multiple certificates must meet ABR-MOC requirements specific to the certificates held. Diplomates with lifelong certificates are not required to participate in the MOC, but are strongly encouraged to do so. MOC is based on documentation of individual participation in the four components of MOC: (1) professional standing, (2) lifelong learning and self-assessment, (3) cognitive expertise, and (4) performance in practice. Within these components, MOC addresses six competencies: medical knowledge, patient care, interpersonal and communication skills, professionalism, practice-based learning and improvement, and systems-based practice.

Certification↗

PubMed1995

Therapeutic communities for addictions: a theoretical framework.

Adaptation of therapeutic communities (TCs) for new clients and in different settings has resulted in a diversity of programs with unique treatment protocols and different planned duration of stays. The extent to which the various adaptations retain the essential elements of the TC model is not known, and moreover, casts questions about the general effectiveness of the therapeutic community modality. This paper outlines a theoretical framework of the addiction TC to advance research and guide training, practice, and program development. The essential elements of the TC are organized into four areas: its perspective, treatment approach, program model, and the treatment process. Some implications of a TC theory, model, and method are discussed in terms of research, treatment, and policy issues.

Goals↗

PubMed1996

[Overview--suppression effect of essential trace elements on arteriosclerotic development and it's mechanism].

It is known that the peroxidation of LDL is a trigger for developing arteriosclerosis. The oxidized LDL is produced by either oxidative stress or a few oxidant. Selenium decreased in serum and some organs of stroke-prone spontaneously hypertensive rats (SHRSP), which is a cofactor of glutamine peroxidase. Serum magnesium decreased in patients with diabetes mellitus, with ischemic heart disease, with essential hypertension and with cerebral vascular lesions. Calcium to magnesium ratio was higher in some organs of SHRSP as compared to Wistar Kyoto rats (WKY). These changes accelerated vascular lesions in SHRSP.

Animals↗

PubMed1998

Choice, isolation, and preparation of cells for bioartificial vascular grafts.

Preparation of cells and tissues for bioartificial vascular grafts is discussed from the viewpoint of tissue engineering. In general, a neointima is not formed on vascular prostheses except at the anastomotic sites. Graft surfaces do not heal and are covered with fresh thrombi for a long period of time after implantation. The delayed healing is, so to speak, an intractable ulcer of the vascular wall. To overcome this problem, we have developed a tissue fragment transplantation method. We consider that neointima formation of vascular prostheses after implantation is a product of tissue engineering in vivo. Therefore, 3 essential elements for tissue engineering, i.e., cells, extracellular matrices, and cytokines, are required for neointima formation. Synthetic vascular prostheses lack one or more of these elements. In this study we demonstrated a standard healing process of fabric vascular prostheses and an antithrombogenic polymer graft using animal models. Then we showed the tissue fragment transplantation method using venous tissues, adipose tissues, and bone marrow. This method provided the 3 essential elements to the prostheses. To allow these elements to be actively engaged in neointima formation, we treated cells and tissues as clumps without enzymatic digestion. We also took advantage of the in vivo environment. With the results we demonstrate our way of thinking in relation to bioartificial vascular grafts.

Adipose Tissue↗

PubMedDate not supplied

Major and trace elements in spruce needles by NAA.

Concentrations of 23 elements in needles of Norway spruce (P. abies) have been determined at 47 sites. It is shown that a thorough removal of the aerosols sitting on the needles surface is necessary in order to get the inherent needle concentrations. Neutron activation was used to determine concentrations from 10(-9) to 10(-2) g/g. Irradiation and counting conditions are given. The essential elements, Ca, Cl, Cu, Fe, K, Mg, Mn, P, Zn, and the nonessential elements, Al, As, Ba, Br, Co, Cs, Hg, La, Na, Rb, Sb, Sc, Sr, and V, could be determined. The concentrations of most elements are about a factor of 6 smaller than the mean concentrations in land plants. Analytical reproducibility was much better than the variation among individual trees, and the variation within sites is smaller than among sites. In general, essential elements have smaller variations than nonessential elements. For some elements, variations between sites are owing to differences in the soil pH or the emission situation.

Neutron Activation Analysis↗

PubMed1999

Concentrations of essential trace elements in maternal serum and the effect on birth weight and newborn body mass index in sub-arctic and arctic populations of Norway and Russia.

BACKGROUND: This project is part of an assessment of the impact of environmental factors on human health in the Kola Peninsula of Russia and the neighboring arctic area of Norway. Pregnant women and their newborns were studied to explore a relationship between maternal status of essential metals and birth weight. METHODS: Life-style information and serum specimens were collected from at least 50 consecutive mother-infant pairs from hospital delivery departments in three Russian and three Norwegian communities (N=151 and 167, respectively). Pregnancy outcomes were verified by consulting medical records. Copper, selenium and zinc in serum were determined by atomic absorption spectrometry and ferritin by an automated analyzer method. RESULTS: Mean birth weight and child's body mass index (BMIC) were significantly lower in the Russian group (p<0.001), with or without adjustment for gestational age. Copper, iron (as ferritin) and selenium serum concentrations were in the normal range, while zinc levels in both countries were mostly below the lower limit (10.8 micromol/L) of reported reference intervals. A positive correlation between zinc and birth weight or BMIC was only observed for concentrations exceeding 10.8 micromol/L. Analysis by quartiles showed that maternal urinary creatinine and birth weight were negatively correlated (p=0.001). The influence of the different elements on BMIC, grouped by quartiles, was significantly positive only for selenium (p=0.03) and ferritin (p=0.02), while there was no significant relationship for copper or zinc. Adjustment of birth weight and BMIC for gestational age did not alter substantially the various associations indicated. CONCLUSIONS: With the exception of zinc, the mineral status of delivering women in arctic and sub-arctic regions of Norway and western Russia appears to be adequate. The significantly lower BMIC for the Russian group suggests the likely occurrence of nutritional deficiencies during pregnancy in Russia. However, the significant contribution of a country factor in the predictive model implies that the maternal serum trace-element concentrations explored in this study are incomplete indicators of fetal undernourishment.

Adult↗

PubMed1995

A cluster of basic amino acids within an alpha-helix is essential for alpha-subunit recognition by the glycoprotein hormone N-acetylgalactosaminyltransferase.

The glycoprotein hormone N-acetylgalactosaminyltransferase is responsible for synthesis of Asn-linked oligosaccharides terminating with GalNAc-4-SO4 on lutropin, thyrotropin, and the uncombined glycoprotein hormone alpha subunit. We previously established that a recognition determinant for the N-acetylgalactosaminyltransferase is contained within a 22-amino acid glycopeptide fragment of the alpha subunit. We proposed that the tripeptide Pro-Leu-Arg is an essential element of the recognition determinant. Using site-directed mutagenesis we have examined the role of individual amino acids in recognition by the glycoprotein hormone N-acetylgalactosaminyltransferase. Within the sequence Pro40-Leu41-Arg42-Ser43-Lys44-Lys45, Lys44, and Lys45, as well as Arg42 of the tripeptide, are essential for recognition. Substitution of the Leu41 with other amino acids can either increase or decrease the rate of GalNAc transfer over an 8-fold range, suggesting that the middle amino acid of the tripeptide plays a modulatory role in recognition. The critical Leu41-Arg42 and Lys44-Lys45 residues are present on the same surface of an alpha-helix, which projects from the surface of the alpha subunit. Our results indicate that an essential element of the recognition determinant consists of a cluster of basic residues and that neutral but not negatively charged residues are tolerated within this cluster.

Acetylgalactosamine↗

PubMed1983

Quick-blot: selective mRNA or DNA immobilization from whole cells.

Quick-blot, a method for selectively immobilizing either mRNA or DNA on nitrocellulose, is described in detail. Essential elements of the procedure for immobilizing DNA include tissue lysis, proteinase K treatment, solubilization of nucleic acids in hot 12.2 molal NaI, passage through a nitrocellulose filter, and acetylation of residual protein with acetic anhydride. Advantages include speed, quantitative recovery, low background, and elimination of the usual baking step. Essential elements of the procedure for selectively immobilizing mRNA include dissolving cells in Brij-35 and desoxycholate, proteinase K treatment, solubilizing nucleic acids in room temperature 12.2 molal NaI, filtration through nitrocellulose, and acetylation of residual protein. Advantages include selective immobilization of mRNA but not tRNA, rRNA, or DNA, and the maintenance of biological activity of the immobilized mRNA. Control experiments to optimize the procedures and examples of their application are shown.

Cells↗

PubMed1988

Systemic lupus erythematosus activity. An operational definition.

Improved diagnosis and treatment have reduced mortality from SLE and present us with an opportunity to consider SLE in finer distinctions than alive or dead. Although much has been learned about SLE without a gold standard of disease activity or a universally agreed-upon definition of SLE activity, standardization of one or more measures would greatly enhance our ability to compare results from different centers and to communicate more precisely. It is unlikely that any of the existing measures or any ones to be developed will completely satisfy everyone's needs but it is pointless to proliferate new ones without testing their metric properties. Some differences in concept are desirable, particularly for investigators who have specialized interests or insights, but each should meet criteria of reliability and validity and have explicit definitions of terms, rules for their ascertainment, and the time period covered. Moreover, agreement on minimum essential elements of any SLE activity measure and their operational definitions would be a boon. SLE activity is one dimension in the disease pathway of lupus and implies a continuous phenomena that is potentially reversible. Organ damage, another point in the path of causation, connotes irreversible disease. We recommend that minimum essential elements be based on their frequency of occurrence, biological sensibleness, and the likelihood that degrees of activity can be rated reliably to show a change in a clinical state. The rating should be independent of whether a therapy is employed. Since activity is always considered with severity, the two dimensions could be recognized in the scale. Severity can be used to expand a scale's gradations if a symptom or sign is present. Severity could be rated by the need to treat with immunosuppressive agents, the need to follow the patient more closely, or the functional or prognostic consequences of the manifestation. For every organ system clinical judgment should be used to decide whether and how the scale should be constructed. For instance, in skin manifestations one could construct a scale by describing the extent of the lesion over the body and whether the lesion has potential for scarring, i.e., involving the dermis. However, the presence of, rather than the number of, cytoid bodies might be the only thing that is clinically important in rating the eye.(ABSTRACT TRUNCATED AT 400 WORDS)

Diagnosis-Related Groups↗

PubMed2005

A 2,000-year record of mercury and ancient civilizations in seal hairs from King George Island, West Antarctica.

The concentrations of total mercury (Hg(T)) and three bio-essential elements (phosphor, potassium, sodium) were analyzed in Antarctic seal hairs from a lake core spanning the past 2,000 years and collected from King George Island (63 degrees 23'S, 57 degrees 00'W), West Antarctica. The Hg(T) concentration shows a significant fluctuation while the levels of the three bio-essential elements remain almost constant. The rise and fall of the Hg(T) concentration in the seal hairs are found to be closely coincided with ancient activities of gold and silver mining using Hg-amalgamation process around the world, especially in the Southern Hemisphere. Briefly, Hg(T) levels are high during five episodes of extensive gold and silver mining activities--Rome Empire and China Han Dynasty (approximately 18-300 A.D.), Maya period and China Tang (750-900 A.D.), Incas civilization and Christian Kingdom (1200-1500 A.D.), New world (1650-1800 A.D.), and modern industry period (1840 A.D.-present); they are low during four time periods of reduced gold and silver mining activities--the China Han and Rome fall (since 300 A.D.), Maya fall and Wartime period in China (1050-1250 A.D.), Pizarro coming (ca. 1532 A.D.) and Independence War of South America (1800-1830 A.D.). Two profiles of Hg(T) in other two lake cores, one affected by seal excrements and the other by penguin droppings, from the same region are similar to the one in seal hairs. The Hg concentration profile in the seal hairs is significantly correlated with the one in a peat bog of Southern Chile near King George Island. Since Hg is existent mainly at the form of methyl-mercury in seal hairs, this correlation supports a relationship and link between atmospheric mercury concentration and methyl-mercury production. Comparing with samples from American and European continents, the Antarctic seal hairs provide an archive of total mercury concentration in surface seawater of the South Ocean less affected by regional human activities, and this archive may provide a good reference for assessing the global Hg emissions, depositions and recycling in the past thousand years.

Animals↗

PubMed1987

Basic considerations in assessing and preventing occupational infections in personnel working with nonhuman primates.

Transmission of zoonotic infections of nonhuman primates to human contacts is a documented occupational hazard. Although the list of naturally occurring and experimentally induced infections of nonhuman primates is extensive the risks of transmission may substantially be reduced by the use of good animal care practices, appropriate protective measures and devices, and suitable animal facilities. The essential elements of good animal care practices include high levels of personal hygiene; minimizing the creation of potentially infectious aerosols and droplets; use of personal protective clothing, devices, and vaccines; a system for reporting, evaluating, and treatment of occupational exposures and infections; and animal facilities appropriate for the species being used and the activities conducted. These essential elements are described and discussed in the context of published voluntary codes of practice--notably "Biosafety in Microbiological and Biomedical Laboratories."

Aerosols↗

PubMed2001

Report of the American Foundation for Urologic Disease (AFUD) Thought Leader Panel for evaluation and treatment of priapism.

PURPOSE: Patients with priapism often develop permanent erectile dysfunction and personal sexual distress. This report is intended to help educate the public by reviewing the varied definitions and classifications of priapism and limited literature reports of pathophysiology, diagnosis and treatment outcomes of priapism. The AUA priapism guidelines committee is responsible for creating consensus as to appropriate individual patient management of priapism by physicians. MATERIALS AND METHODS: A multidisciplinary panel, consisting of 19 thought leaders in priapism, was convened by the Sexual Function Health Council of the American Foundation for Urologic Disease to address pertinent issues concerning the role of the urologist, primary care providers and other health care professionals in the education of the public regarding management of men with priapism. The panel utilized a modified Delphi method and built upon the peer review literature on priapism. RESULTS: The Thought Leader Panel recommended adoption of the definition of priapism as a pathological condition of a penile erection that persists beyond or is unrelated to sexual stimulation. Priapism is stressed to be an important medical condition that requires evaluation and may require emergency management. The classification system is categorized into ischemic and non-ischemic priapism. Essential elements of the ischemic classification are the inclusion of: (i) clinical characteristics of pain and rigidity; (ii) diagnostic characteristics of absence of cavernosal arterial blood flow; (iii) pathophysiological characteristics of a closed compartment syndrome; (iv) a time limit of 4 h prior to emergent medical care; and (v) a description of the potential consequences of delayed treatment. Essential elements of the non-ischemic classification are the inclusion of: (i) clinical characteristics of absence of pain and presence of partial rigidity; (ii) diagnostic and pathophysiological characteristics of unregulated cavernosal arterial inflow; and (iii) the need for evaluation but emphasizing the lack of a medical emergency. The panel recommended adoption of a rational management algorithm for the assessment and treatment of priapism where the cornerstone of initial assessment includes a careful clinical history, a focused physical examination and selected laboratory and/or radiologic tests. The panel recommended that specific criteria and clinical profiles requiring specialist referral should be identified. The panel further recommended that patient (and partner) needs and education concerning priapism should be addressed prior to therapeutic intervention, however only in the case of chronic management or post acute presentation evaluation should this delay intervention. Treatment goals to be discussed include management of the priapism with concomitant prevention of permanent and irreversible erectile dysfunction and associated psychosocial consequences. The panel recommended that when specific therapies for priapism are required, a step-care treatment approach based upon reversibility and invasiveness should be followed. CONCLUSIONS: The Thought Leader Panel calls for research to expand our understanding of the prevalence and diagnosis of priapism and education to create awareness among the public of the potential urgency of this condition. Critical areas to be addressed include the multiple pathophysiologies of priapism as well as multi-institutional trials to objectively assess safety and efficacy in the various treatment modalities.

Humans↗

PubMed1994

A sequence related to a DNA recognition element is essential for the inhibition by nucleotides of proton transport through the mitochondrial uncoupling protein.

The uncoupling protein (UCP) is uniquely expressed in brown adipose tissue, which is a thermogenic organ of mammals. The UCP uncouples mitochondrial respiration from ATP production by introducing a proton conducting pathway through the mitochondrial inner membrane. The activity of the UCP is regulated: nucleotide binding to the UCP inhibits proton conductance whereas free fatty acids increase it. The similarities between the UCP, the ADP/ATP carrier and the DNA recognition element found in the DNA binding domain of the estrogen receptor suggested that these proteins could share common features in their respective interactions with free nucleotides or DNA, and thus defined a putative 'nucleotide recognition element' in the UCP. This article provides demonstration of the validity of this hypothesis. The putative nucleotide recognition element corresponding to the amino acids 261-269 of the UCP was gradually destroyed, and these mutant proteins were expressed in yeast. Flow cytometry, measuring the mitochondrial membrane potential in vivo, showed increased uncoupling activities of these mutant proteins, and was corroborated with studies with isolated mitochondria. The deletion of the three amino acids Phe267, Lys268 and Gly269, resulted in a mutant where proton leak could be activated by fatty acids but not inhibited by nucleotides.

Amino Acid Sequence↗

PubMed1986

Transport and distribution of copper injected into an albumin-deficient (analbuminemic) rat.

Copper (Cu) concentrations in blood, liver, kidney, spleen and pancreas of an albumin-deficient (Nagase analbuminemic) rat (NAR) were compared with those of a control (Sprague-Dawley) rat (SDR). Cu concentrations were significantly higher in the blood and significantly lower in the liver of the NAR strain than those of the SDR strain in female control (saline-injected) groups at 8 weeks old. Female NAR and SDR 8-week-old rats were injected i.p. with Cu at a single dose of 2.0 mg/kg body wt and killed 18 hr later. Concentrations of Cu and other essential elements in the blood, liver, kidney, spleen and pancreas were determined simultaneously by inductively coupled plasma-atomic emission spectrometry. Cu concentration in the liver was significantly lower in the NAR than in the SDR strain suggesting a role for albumin as a carrier protein of free Cu ions in the blood. The effects of Cu loading on other essential elements (Zn, Fe, Ca, Mg, P) were also compared between the NAR and SDR strains.

Animals↗

PubMed2003

Copper, zinc, and selenium in human blood and urine after injection of sodium 2,3-dimercaptopropane-1-sulfonate: a study on subjects with dental amalgam.

This study investigated the effects of a single dose of intravenously administered sodium 2,3-dimercaptopropane-1-sulfonate (DMPS) on the essential elements copper, zinc, and selenium in human blood and urine. The possible role of dental amalgam was also addressed. Eighty individuals, divided in four groups according to the presence or absence of dental amalgam fillings and symptoms self-related to such fillings, were given DMPS (2 mg/kg body wt) and 500 mL Ringer's acetate intravenously. Urine and blood were collected prior to the injection, and thereafter at intervals over a 24-h period. Cu, Zn, and Se concentrations were determined by atomic absorption spectrometry methods. A statistically significant increase in the concentrations of Cu and Zn in urine was observed 30 and 120 min after the DMPS injection compared to the preinjection concentrations. The concentrations of Se were not affected. The cumulated excretion over 24 h after DMPS injection constitutes only from 0.1% to 0.7% of the body content of these elements. There was no effect of different amalgam statuses on Cu and Zn excretion. We found a temporary decrease (4-7%) in the concentrations of Cu, Zn, and Se in blood 15 and 30 min after DMPS, but this seems to be the result of dilution factors. Administration of a single dose of DMPS does not affect the body stores of the essential elements Cu, Zn, and Se.

Adult↗