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PubMed1996

Virginia Henderson and her timeless writings.

This paper provides a reflection on the written works of Miss Virginia Avenel Henderson. Miss Henderson is a nurse, a scientist, an artist and a quintessential human being--all traits which informed her written output. Nursing practice, research and education were all subjects of her extensive chronicle. The four-volume Nursing Studies Index is her contribution to nursing research. The Index was sandwiched between two revisions of Principles and Practice of Nursing (5th and 6th eds), the placement of which caused the Index to focus on practice and the Principles (6th ed.) to be based on research. The sixth edition of Principles, written with Gladys Nite and 17 contributors, is considered the most important single professional document written in the twentieth century. The book synthesizes nursing practice, education, theory and research in an age when many nurses are challenged by the seeming incongruity in these essential professional functions.

Abstracting and Indexing↗
PubMed1995

Genetic map of Salmonella typhimurium, edition VIII.

We present edition VIII of the genetic map of Salmonella typhimurium LT2. We list a total of 1,159 genes, 1,080 of which have been located on the circular chromosome and 29 of which are on pSLT, the 90-kb plasmid usually found in LT2 lines. The remaining 50 genes are not yet mapped. The coordinate system used in this edition is neither minutes of transfer time in conjugation crosses nor units representing "phage lengths" of DNA of the transducing phage P22, as used in earlier editions, but centisomes and kilobases based on physical analysis of the lengths of DNA segments between genes. Some of these lengths have been determined by digestion of DNA by rare-cutting endonucleases and separation of fragments by pulsed-field gel electrophoresis. Other lengths have been determined by analysis of DNA sequences in GenBank. We have constructed StySeq1, which incorporates all Salmonella DNA sequence data known to us. StySeq1 comprises over 548 kb of nonredundant chromosomal genomic sequences, representing 11.4% of the chromosome, which is estimated to be just over 4,800 kb in length. Most of these sequences were assigned locations on the chromosome, in some cases by analogy with mapped Escherichia coli sequences.

Chromosome Mapping↗
PubMed1999

Need for a standard report and future directions in pancreatic resections for cancer.

The ability to compare treatment results is essential for the proper evaluation of treatment protocols. Especially in the case of exocrine pancreatic cancer different classifications and documentation systems hinder the comparison between institutions and do not allow multicenter analysis across the world. This might explain the vastly different results of similar therapeutical trials and studies. In the classifications used at present, the features included, as well as terminology and description, vary greatly. First attempts to stage pancreatic malignancies according to UICC criteria were mentioned in the 1987 edition. These rules were predominantly based on the suggestions of the AJCC Cancer of the Pancreas Task Force of 1981 and have since not been changed. In Japan a different staging system has emerged and was first published by the Japanese Pancreatic Society (JPS) in 1986: General Rules for Surgical and Pathological Studies on Cancer of the Pancreas. The major difference between the two classifications concerns the evaluation of local tumor growth and the extent of lymph node involvement. Unfortunately most attempts to 'restage' Western patients postoperatively according to the JPS criteria, or vice versa, in order to compare treatment results have not added to a clearer understanding. Much in contrary, the results were frequently confusing since not comparable data were nevertheless retrospectively compared. Thus, a uniform standard report is needed, leading to prospective data acquisition and biometric analysis of outcome. The report should serve as a standard format for worldwide data acquisition and documentation and thereby become the common language to describe diagnosis, treatment, pathology and outcome of pancreatic cancer patients undergoing surgical therapy. It should enable: (1) inter-institutional data exchange from different staging systems; (2) comparisons between institutions on an international basis; (3) quality management in clinical practice and studies, and (4) reliable insight into tumor biology and differences in growth patterns.

Forms and Records Control↗
PubMed1997

Convergent and criterion-related validity of the Behavior Assessment System for Children-Parent Rating Scale.

Examined aspects of the validity of the Behavior Assessment System for Children (BASC; Reynolds & Kamphaus, 1992) Parent Rating Scale (BASC-PRS) in 156 children with cross-setting disruptive behavior. The BASC-PRS is a recently published multidimensional measure composed of conceptually derived scales created for use in conjunction with psychiatric and educational classification systems. Convergent validity was assessed through correlations of BASC-PRS scale scores with scale scores on the Child Behavior Checklist/4-18 (CBCL/4-18; Achenbach, 1991b). Criterion-related validity was evaluated as the ability of BASC-PRS and CBCL/4-18 scales to predict membership in diagnostic groupings (no diagnosis, attention deficit hyperactivity disorder [ADHD] only, and ADHD with a comorbid externalizing disorder) derived via structured interviews based on the third, revised edition of the Diagnostic and Statistical Manual of Mental Disorders (American Psychiatric Association, 1987). Results showed the validity of the BASC-PRS to be comparable to that of the CBCL/4-18. Given its conceptually derived scales, the BASC-PRS may prove to be a useful-tool for assessing childhood disruptive behavior.

Attention Deficit Disorder with Hyperactivity↗
PubMed1992

Structure of a receptor-binding fragment from human luteinizing hormone beta-subunit determined by [1H]- and [15N]nuclear magnetic resonance spectroscopy.

The structure of the glycoprotein hormones (LH, CG, FSH, and TSH) and their mechanism of receptor recognition are problems of long-standing interest and speculation. Here we describe the two-dimensional [1H]nuclear magnetic resonance ([1H]NMR) analysis of a linear peptide model for the intercysteine sequence (38-57) from the beta-subunit of human (h) LH. This sequence contains functional determinants for receptor binding and postreceptor activation and is predicted by computer-based modeling to fold as a compact minidomain containing a central amphipathic helix. To test this prediction, an Arg-extended disulfide-free (38-57) analog of enhanced solubility was prepared for complementary circular-dichroic and two-dimensional NMR studies. The linear peptide retains ovarian membrane receptor-binding activity. Although the peptide is not highly structured in aqueous solution, circular-dichroic analysis shows partial alpha-helix formation in a lipophilic medium (50% trifluoroethanol). Complete sequential assignment is obtained in 50% trifluoroethanol based on homonuclear and [15N]edited heteronuclear NMR methods. alpha-Helix-related (i,i + 3) connectivities are observed by nuclear-Overhauser effect spectroscopy that define an amphipathic alpha-helical segment (residues 41-48). Additional long range nuclear-Overhauser effects are observed in the C-terminal region that are consistent with beta-turns involving one or more proline residues; these may serve to reverse the direction of the peptide chain. A nuclear-Overhauser effect contact is identified between residues 38 and 55 at opposite ends of the linear sequence, suggesting that a loop configuration is significantly populated in this solvent system. These results, taken together, characterize elements of ordered structure in the 38-57 peptide, which appear to be distinguishing features of hLH (and the homologous region of hCG). We propose that the structure of this peptide provides a model for the structure of the corresponding region of native hLH in the hormone-receptor complex.

Amino Acid Sequence↗
PubMed1993

["Tang-ye Bencao" excavated from the Asakura family site].

Burnt fragments of a medical manuscript were excavated from the Asakura family site in 1985. From the study of the characters seen on the fragments, the following conclusions have been drawn: 1) The fragments are parts of a manuscript of the "Tang-ye Bencao", a book of materia medica written by Wang Haogut in the Yuan dynasty of China. 2) There is a high possibility that this manuscript of the "Tang-ye Bencao" was a faithful copy based on the "Dongyuan Shishu" edition published by the Xiongshi Meiyintang in 1508, during the Ming dynasty of China. 3) For all of the 36 fragments on which characters could be seen, a corresponding part of the Xiongshi edition could be found, and every character has been deciphered correctly. Assumptions were made about the characters and the corresponding parts of the Xiongshi edition for those fragments which could not be torn off. 4) For the latter part of the Muromachi period in Japanese history, a relationship was found between the acceptance of Chinese medicine through a group of books of the Xiongshi edition, the cultures of the Asakura family and the commercial town Sakai, and the activities of some intellectuals.

China↗
PubMed2002

[The meaning of the sixth edition of "Organon der Heilkunst"].

Like any artist, the paractitioner of the healing art should exactly know his tools, i.e. his medicines and the directions for their application. In addition, he should be able to rely on their genuineness. Regarding the tool "Organon", considerable uncertainty has been expressed by some physicians about the authenticity of Hahnemann's instructions for preparing and applying Q-potencies, as described in the sixth edition of the Organon of Medicine published by Richard Haehl in 1921. Since 1992, however, the first text-critical edition of the sixth edition of the Organonis available. Unlike Haehl's edition this one is exclusively based on Hahnemann's original manuscript and precisely transcribing all its handwriting, vouches for its authenticity. Hence there is no reason left to ignore Hahnemanns instructions concerning Q-potencies. This paper presents the history of the reception of Q-potencies as well as their prerequisites and evolution up to Hahnemann's final modifications of his earlier directions. As it turns out, these late instructions of Hahnemann do not mean complete change of all his previous opinions. Rather they are the logical completion of a course followed by him for ten years already. Q-potencies were Hahnemann's solution of the following therapeutic dilemma: on the one side physicians are inclined to repeat the dose of a high potency as often as possible in order to accelerate the process of healing; on the other side they should refrain from repeating the dose to avoid violent aggravations of the state of the patient.

Books↗
PubMedDate not supplied

[Effectiveness of a modified Madde-type mastectomy in patients with breast cancer of I-II stage].

Effectiveness of mastectomy with two breast muscles preserved and total lymphdissection (Malden surgical operation) in I-II stage breast cancer patients has been studied. The control group has been operated using classical mastectomy after Golsted and its modified variant named after Peity. The degree of the disease dissemination was confirmed pathohistologicaly based on the 5-th edition of TNM system. It was established that the 5 year survival period among patients with primary tumor size getting pT1-2 doesn't depend on a volume of a surgical operation but correlates with the number of regional lymph nodes metastasis (pN1). It has totaled 85.3-87.2 % among pT1 pNO MO breast cancer patients, 73.5%--pT2 pNo MO, 63.7-69.3%--pT1-2pN1Mo. 81% of patients who had 1-3 regional lymph nodes metastasis is still alive after the 5 year survival period--57.2%, of those who had 4-9 regional metastasis overpassed this 5 year survival period and 10 or over regional metastasis survive only about 19%.

Axilla↗
PubMed1989

[The history of German-language publications of Freud].

The present state of the German editions of Freud is described and documented as the result of a historical development taking place in three phases: the history of editions as history of persecution. Based on her longstanding personal experience as editor of Freud, the author relates the third phase (since 1960).

Austria↗
PubMed1993

Structure of the complex between pyridoxal 5'-phosphate and the tyrosine 225 to phenylalanine mutant of Escherichia coli aspartate aminotransferase determined by isotope-edited classical Raman difference spectroscopy.

The azomethine (Schiff base) linkage between the epsilon-amino group of active-site lysine 258 and the carbonyl moiety of enzyme-bound pyridoxal 5'-phosphate (PLP) normally exhibits absorbance maxima at ca. 360 (high-pH form) or ca. 430 nm (low-pH form). However, the absorbance maximum is shifted from 358 to 386 nm, a value which is similar to that of free PLP (lambda max = 388 nm), in a mutant form of Escherichia coli aspartate aminotransferase (AATase) in which tyrosine 225, which normally donates a hydrogen bond to the phenolate function of PLP, has been replaced with phenylalanine (Y225F). This spectral shift suggested that PLP binds to Y225F as the free aldehyde. The following evidence from isotope-edited classical Raman spectroscopy proves conclusively that the near-UV spectrum is anomalous and that PLP is bound to Y225F as a Schiff base: (1) A strong cofactor peak at 1630 cm-1 in the holoenzyme-minus-apoenzyme difference spectrum of the unprotonated form of Y225F is red-shifted by 18 cm-1 in enzyme labeled with 15N at lysine 258 and other positions. (2) This isotope-induced red shift is similar to that observed in the unprotonated form of the model Schiff base, PLP-valine. (3) The Raman spectrum of Y225F is unchanged in H(2)18O, while peaks at ca. 1670 cm-1 in the spectrum of free PLP or in that of a mutant of AATase in which Lys-258 is replaced with Ala, are red-shifted by ca. 30 cm-1 in H(2)18O.(ABSTRACT TRUNCATED AT 250 WORDS)

Aspartate Aminotransferases↗
PubMed2005

Effects of conserved RNA secondary structures on hepatitis delta virus genotype I RNA editing, replication, and virus production.

RNA editing of the hepatitis delta virus (HDV) antigenome at the amber/W site by the host RNA adenosine deaminase ADAR1 is a critical step in the HDV replication cycle. Editing is required for production of the viral protein hepatitis delta antigen long form (HDAg-L), which is necessary for viral particle production but can inhibit HDV RNA replication. The RNA secondary structural features in ADAR1 substrates are not completely defined, but base pairing in the 20-nucleotide (nt) region 3' of editing sites is thought to be important. The 25-nt region 3' of the HDV amber/W site in HDV genotype I RNA consists of a conserved secondary structure that is mostly base paired but also has asymmetric internal loops and single-base bulges. To understand the effect of this 3' region on the HDV replication cycle, mutations that either increase or decrease base pairing in this region were created and the effects of these changes on amber/W site editing, RNA replication, and virus production were studied. Increased base pairing, particularly in the region 15 to 25 nt 3' of the editing site, significantly increased editing; disruption of base pairing in this region had little effect. Increased editing resulted in a dramatic inhibition of HDV RNA synthesis, mostly due to excess HDAg-L production. Although virus production at early times was unaffected by this reduced RNA replication, at later times it was significantly reduced. Therefore, it appears that the conserved RNA secondary structure around the HDV genotype I amber/W site has been selected not for the highest editing efficiency but for optimal viral replication and secretion.

Adenosine Deaminase↗
PubMed1995

Alternative mRNA splicing and differential promoter utilization determine tissue-specific expression of the apolipoprotein B mRNA-editing protein (Apobec1) gene in mice. Structure and evolution of Apobec1 and related nucleoside/nucleotide deaminases.

Apolipoprotein (apo) B mRNA editing consists of a C-->U conversion involving the first base of the codon CAA, encoding Gln 2153, to UAA, a stop codon. Editing occurs in the intestine only in most mammals, and in both the liver and intestine in a few mammalian species including mouse. We have cloned the cDNA for the mouse apoB mRNA editing protein, apobec1. Expression of mouse apobec1 cDNA in HepG2 cells results in the editing of the intracellular apoB mRNA. The cDNA predicts a 229-amino acid protein showing 92, 66, and 70% identity to the rat, rabbit, and human proteins, respectively. Based on the estimated values of divergence of apobec1 sequences in terms of the numbers of synonymous and non-synonymous suhstitutions per site, we found that apobec1 is a fairly rapidly evolving protein. Sequence comparison among mammalian apobec1 sequences has permitted the identification of seven conserved regions that may be functionally important for editing activity. We present a phylogenetic tree relating apobec1 sequences to double-stranded RNA adenosine deaminase and other nucleotide/nucleoside deaminases. Northern blot analysis indicates that apobec1 mRNA exists in two different sizes, a approximately 2.2-kilobase (kb) form in small intestine and a approximately 2.4-kb form in liver, spleen, kidney, lung, muscle, and heart. To study the molecular basis for the different sized apobec1 mRNAs, we cloned the apobec1 gene and characterized its exon-intron organization together with the sequences expressed in the hepatic and intestinal mRNA. The mouse apobec1 gene contains 8 exons and spans approximately 25 kb, and is located in chromosome 6. The major hepatic mRNA contains all 8 exons, whereas the major small intestinal mRNA misses the first 3 exons and its transcription is initiated in exon 4. The intestinal mRNA also contains at its 5' end a unique 102-nucleotide piece that is absent in the liver mRNA. We also identified two alternatively spliced hepatic apobec1 mRNAs with different acceptor sites in exon 4. Transient expression studies using promoter-reporter gene constructs in HeLa, Hepa, and Caco-2 cells indicate that the 5'-flanking sequences of the liver mRNA (i.e. upstream of exon 1) have predominantly hepatic promoter activity and the 5'-flanking sequences of the major small intestine mRNA (i.e. upstream of exon 4) have preferential intestinal promoter activity.(ABSTRACT TRUNCATED AT 400 WORDS)

APOBEC-1 Deaminase↗
PubMed2004

Folate intake, serum folate, serum total homocysteine levels and methylenetetrahydrofolate reductase C677T polymorphism in young Japanese women.

Various factors influence folate status and requirements. To investigate the folate status in young Japanese women (n=340, 20-22 y), I determined the serum folate and total homocysteine (tHcy), and examined the influence of methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism on folate status in a subgroup of 252 of the women. I calculated folate consumption based on records of food intake weighed over 3 d using the standard Tables of Food Composition in Japan (5th revised edition) and the US Food Composition Table based on the USDA nutrient database excluding fortification. Serum folate and total homocysteine (tHcy) levels were determined by chemiluminescent-competitive protein binding assay and HPLC, respectively. The mean intake of folate was 323+/-133 and 196+/-71 microg/d, and 86.5% and 42.1% of the participants consumed more than the RDA of 200 microg of folate, according to the Japanese and US tables, respectively. The main sources of dietary folate were vegetables, green tea and bread. Serum folate levels were significantly correlated with folate intake (r=0.249, p<0.001). Serum tHcy levels were above 15 micromol/L in four participants. I found significant negative correlations between serum tHcy and folate intake (r=-0.175, p<0.05), and between serum tHcy and serum folate (r=-0.297, p<0.0001). The frequencies of the CC, CT and TT genotypes of the MTHFR gene were 32.9, 51.6 and 15.5%, respectively. Among individuals with the TT genotype, serum folate and tHcy levels were lower and higher, respectively, than in those with the other genotypes, regardless of folate intake above RDA. These data suggest that the current RDA of folate estimated based on foreign data might not be sufficient for Japanese and that this value might require reassessment.

Adult↗
PubMed2006

The importance of RNA structure in RNA editing and a potential proofreading mechanism for correct guide RNA:pre-mRNA binary complex formation.

RNA editing in trypanosomes is a post-transcriptional process responsible for correcting the coding sequences of many mitochondrial mRNAs. Uridine bases are specifically added or deleted from mRNA by an enzymatic cascade in which a pre-edited mRNA is cleaved specifically, uridine bases are added or removed, and the corrected mRNA is ligated. The process is directed by RNA molecules, termed guide RNAs (gRNA). The ability of this class of small, non-coding RNA to function in RNA editing is essential for these organisms. Typically, gRNAs are transcribed independent of their cognate mRNA and anneal to form a binary RNA complex. An exception from this process is the cytochrome oxidase subunit II (COII) mRNA, which encodes its gRNA within its 3' untranslated region. This gRNA lacks the ability to function in trans. Using an in vitro editing assay, we find that improving thermodynamic stability to the anchor region through increased Watson-Crick base-pairing is sufficient to impart trans editing activity. We further show that a point mutation outside the known functional regions of a gRNA induces both a conformational rearrangement of the gRNA and causes a decrease in the rate of editing. Taken together, these results lead us to propose a model for a potential proofreading step in the formation of a gRNA:pre-edited mRNA binary complex. The mechanism relies on the thermodynamic stability supplied to the RNA complex through Watson-Crick base-pairing. Through mutations in the gRNA, we demonstrate the importance of gRNA structure to the RNA editing reaction.

3' Untranslated Regions↗
PubMed1996

RNA editing of larch mitochondrial tRNA(His) precursors is a prerequisite for processing.

Larch mitochondria contain a'native'tRNAHis which is absent from angiosperms. Sequence comparisons of genomic DNA and cDNA obtained from unprocessed primary transcripts of the larch mitochondrial gene trnH encoding this tRNA revealed three nucleotide discrepancies. These three nucleotide alterations, in the acceptor stem, D stem and anticodon stem respectively, are conversions of genomic cytidines to thymidines in the cDNA (uridines in the tRNA) and thus resemble the RNA editing events observed in nearly all plant mitochondrial mRNAs. Two cases of editing affecting mitochondrial tRNAs from angiosperms have already been described, but we present here the first example of such events in a gymnosperm mitochondrial tRNA. All three editing events correct mismatched C x A base pairs which appear when folding the gene sequence into the standard cloverleaf structure, thereby improving the secondary structure of the tRNA. When incubated with a heterologous potato mitochondrial processing extract, only the edited form of the larch mitochondrial tRNAHis precursor was efficiently processed in vitro. These data strongly suggest that editing of larch mitochondrial tRNAHis is a prerequisite for its processing.

Base Sequence↗
PubMed1992

RNA editing in the mitochondria of a conifer.

A 712-base portion of the mitochondrial gene coxI and the corresponding portion of the coxI transcript were amplified by PCR and by RT-PCR, respectively, from the gymnosperm western red cedar. Sequence comparison of amplified coxI DNA and mRNA revealed 26 C-to-U differences that are best explained by RNA editing of the type known to occur in angiosperms. This finding suggests that mitochondrial RNA-editing of the C-to-U type arose before the divergence of gymnosperms and angiosperms and can be considered a feature common to all higher plants.

Amino Acid Sequence↗
PubMed2004

Education-stratified base-rate information on discrepancy scores within and between the Wechsler Adult Intelligence Scale--Third Edition and the Wechsler Memory Scale--Third Edition.

The Wechsler Adult Intelligence Scale--Third Edition (WAIS-III; D. Wechsler, 1997a) and the Wechsler Memory Scale--Third Edition (WMS-III; D. Wechsler, 1997b) are 2 of the most frequently used measures in psychology and neuropsychology. To facilitate the diagnostic use of these measures in the clinical decision-making process, this article provides information on education-stratified, directional prevalence rates (i.e., base rates) of discrepancy scores between the major index scores for the WAIS-III, the WMS-III, and between the WAIS-III and WMS-III. To illustrate how such base-rate data can be clinically used, this article reviews the relative risk (i.e., odds ratio) of empirically defined "rare" cognitive deficits in 2 of the clinical samples presented in the WAIS-III--WMS-III Technical Manual (The Psychological Corporation, 1997).

Educational Status↗