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PubMed1995

Evaluation of a structured outpatient group education program for intensive insulin therapy.

OBJECTIVE: To determine the efficacy and safety of a structured diabetes teaching and treatment program (DTTP) in patients with insulin-dependent diabetes mellitus (IDDM) in an outpatient setting. RESEARCH DESIGN AND METHODS: All patients with IDDM who completed a structured 5-day outpatient DTTP were reevaluated after a mean follow-up of 3 years. A standardized interview was used to assess frequency of severe hypoglycemia, type of insulin treatment, self-monitoring, and other diabetes-related parameters. HbA1c was measured by high-performance liquid chromatography. RESULTS: Of 205 patients, 4 (2%) died during the observation period. HbA1c in the 201 surviving patients decreased significantly from 8.7 +/- 2.0 to 7.5 +/- 1.2% at follow-up (P < 0.001); frequency of severe hypoglycemia decreased from a mean of 0.46 to 0.13 per patient per year (P < 0.001). Hospital admission due to acute metabolic disturbances decreased from 4.5 +/- 11.1 to 1.4 +/- 6.7 days/patient-year (P < 0.001). At follow-up, intensive insulin therapy was carried out by 98% of the patients, and 80% of the patients reported three or more measurements of blood glucose per day. Diabetes-related knowledge had a positive (P < 0.01) and body mass index a negative (P < 0.02) influence on improving HbA1c assessed by multiple regression analysis. Severe hypoglycemia after DTTP was associated with a history of severe hypoglycemia before DTTP (P < 0.001) and the existence of overt diabetic nephropathy (P < 0.05). CONCLUSIONS: A structured outpatient DTTP as used in this study is able to improve overall metabolic control and decrease the frequency of severe hypoglycemia in patients with IDDM.

Adult↗
PubMed2002

Critical effect of the N2 amino group on structure, dynamics, and elasticity of DNA polypurine tracts.

Unrestrained 5-20-ns explicit-solvent molecular dynamics simulations using the Cornell et al. force field have been carried out for d[GCG(N)11GCG]2 (N, purine base) considering guanine*cytosine (G*C), adenine*thymine (A*T), inosine*5-methyl-cytosine (I*mC), and 2-amino-adenine*thymine (D*T) basepairs. The simulations unambiguously show that the structure and elasticity of N-tracts is primarily determined by the presence of the amino group in the minor groove. Simulated A-, I-, and AI-tracts show almost identical structures, with high propeller twist and minor groove narrowing. G- and D-tracts have small propeller twisting and are partly shifted toward the A-form. The elastic properties also differ between the two groups. The sequence-dependent electrostatic component of base stacking seems to play a minor role. Our conclusions are entirely consistent with available experimental data. Nevertheless, the propeller twist and helical twist in the simulated A-tract appear to be underestimated compared to crystallographic studies. To obtain further insight into the possible force field deficiencies, additional multiple simulations have been made for d(A)10, systematically comparing four major force fields currently used in DNA simulations and utilizing B and A-DNA forms as the starting structure. This comparison shows that the conclusions of the present work are not influenced by the force field choice.

Base Pairing↗
PubMed1989

[Evaluation by two-dimensional and doppler echocardiography of the results of percutaneous mitral valvuloplasty].

The purpose of this study was to determine the value of two-dimensional echocardiography and doppler ultrasound in the evaluation of the results and mechanism of percutaneous mitral valvuloplasty. The study involved 200 patients (77 p. 100 female) of mean age 43 +/- 15 years (range 13 to 79 years), most of whom were in NYHA class III or IV. The patients were divided into three groups according to the severity of the anatomical lesions. Group I patients (n = 58) had flexible valves and only minor alterations of the subvalvular structures; group II patients (n = 75) had flexible valves but deeply altered subvalvular structures; group III patients (n = 67) had calcified valves. Following valvuloplasty, the mean transmitral doppler gradient fell from 16 to 5 mmHg (p less than 0.0001) and the mitral valve area, as measured by two-dimensional echocardiography, increased from 1 to 1.9 cm2 (p less than 0.00001); the corresponding values at doppler measurement were 1 and 2 cm2 respectively. In patients successfully dilated, two-dimensional echocardiography showed that the mechanism involved was complete opening of one or both commissures. Before dilatation, 68 patients (34 p. 100) had an usually small degree of mitral regurgitation. After dilatation, grade 3/4 mitral regurgitation was observed in 9 patients (4.5 p. 100). The quality of the results obtained depended on the anatomical lesions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1988

Structural aspects of blood group glycosphingolipids in the gastrointestinal tract.

The epithelial cells of the gastrointestinal tract from different species show a very variable expression of blood group active glycosphingolipids. The core saccharide sequences are typical for the species as, for example, type 1 chains (Gal beta 1----3GlcNAc) are found in the small intestine of man, rat, and pig and type 2 chains (Gal beta 1----4GlcNAc) are found in the small intestine of dog, rabbit, and cat. The mouse is atypical with the ganglioseries as the major core saccharide of the small intestine. Blood group A determinants can be found in the small intestine of man, rat, dog, rabbit, and cat, and the blood group B determinant in man and rabbit. Studies on the blood group active glycosphingolipids along the gastrointestinal tract of rat have revealed a complex distribution. The glandular cells of the stomach and epithelial cells of the large intestine express blood group B active glycosphingolipids. The cores of these are the ganglioseries, and the isogloboseries in the stomach and the lacto- (type 1) and neolactoseries (type 2) in the large intestine. The type 2 component is only expressed as a difucosyl and the type 1 as a monofucosyl compound. The epithelial cells of the small intestine are devoid of blood group B glycolipids, but express blood group H structures of which some has a branched core saccharide. One rat strain is lacking blood group A structures in the small intestine, but another is converting the H precursors to blood group A compounds. Both these strains always express blood group A structures in the large intestine. The expression of blood group A glycosphingolipids in the small intestine is inherited as a dominant trait.

Animals↗
PubMed2005

Generation and validation of a shielding library based on ENDF/B-VI.8.

For various shielding and reactor pressure vessel dosimetry applications, a pseudo-problem-independent neutron-photon coupled MATXS-format library, based on the last release of ENDF/B-VI, has been generated as a part of the update program for KASHIL-E6, which was based on ENDF/B-VI.5. It has a VITAMIN-B6 neutron and photon energy group structures, i.e. 199 groups for the neutron and 42 groups for the photon. The neutron and photon weighting functions and the Legendre orders of scattering are the same as in KASHIL-E6. The library has been validated through some benchmarks: the PCA-REPLICA and NESDIP-2 experiments for the light-water reactor (LWR) pressure vessel facility benchmark, the Winfrith Iron 88 experiment for the validation of the iron data and the Winfrith Graphite experiment for the validation of the graphite data. These calculations were performed by the TRANSX/DANTSYS code system. In addition, the substitutions of the JENDL-3.3 and JEFF-3.0 data for Fe, Cr, Cu and Ni, which are very important nuclides for shielding analyses, were investigated to estimate the effects on the benchmark calculation results.

Algorithms↗
PubMed1973

Some bacteriophages active against Rhizobium trifolii strain W19.

Fourteen soil bacteriophages active against Rhizobium trifolii W19 have been studied which fall into four structural groups. Group 1 phages have contractile tails. Some particles show double base plates to which at least three spikes are attached, and fibers are attached to the base plates. Group 2 phages also have contractile tails. At least five spikes are attached to the base plate, and there are spherical bodies adjacent to the tail, at the ends of fibers attached to the tail base. Group 3 phages have contractile tails, but are larger than phages of groups 1 and 2. The end of the tail has a complex structure. Group 4 phages have long, noncontractile tails. Phages c and I of group 1 and phages a and e of group 2 were chosen for further study. Single-step growth curves were plotted, and absorption constants were measured. The classification into groups was confirmed by using antiserum inactivation. Susceptibility of phage-resistant mutants of R. trifolii W19 to these bacteriophages was determined.

Adsorption↗
PubMed2003

The effects of metacognitive training versus worked-out examples on students' mathematical reasoning.

BACKGROUND: The present study is rooted in a cognitive-metacognitive approach. The study examines two ways to structure group interaction: one is based on worked-out examples (WE) and the other on metacognitive training (MT). Both methods were implemented in cooperative settings, and both guided students to focus on the problem's essential parts and on appropriate problem-solving strategies. AIMS: The aim of the present study is twofold: (a) to investigate the effects of metacognitive training versus worked-out examples on students' mathematical reasoning and mathematical communication; and (b) to compare the long-term effects of the two methods on students' mathematical achievement. SAMPLE: The study was conducted in two academic years. Participants for the first year of the study were 122 eighth-grade Israeli students who studied algebra in five heterogeneous classrooms with no tracking. In addition, problem-solving behaviours of eight groups (N = 32) were videotaped and analysed. A year later, when these participants were ninth graders, they were re-examined using the same test as the one administered in eighth grade. METHOD: Three measures were used to assess students' mathematical achievement: a pretest, an immediate post-test, and a delayed post-test. ANOVA was carried out on the post-test scores with respect to the following criteria: verbal explanations, algebraic representations and algebraic solution. In addition, chi-square and Mann-Whitney procedures were used to analyse cooperative, cognitive, and metacognitive behaviours. RESULTS: Within cooperative settings, students who were exposed to metacognitive training outperformed students who were exposed to worked-out examples on both the immediate and delayed post-tests. In particular, the differences between the two conditions were observed on students' ability to explain their mathematical reasoning during the discourse and in writing. Lower achievers gained more under the MT than under WE condition. CONCLUSIONS: The findings indicate that the kind of task and the way group interaction is structured are two important variables in implementing cooperative learning, each of which is likely to have different effects on mathematical communication and achievement outcomes.

Adolescent↗
PubMedDate not supplied

The role of community organizations in the transformation of the health services delivery system in the Montreal metropolitan area.

In 1995 the Montreal Regional Health and Social Services Board began a major process of change to its health care system. This transformation places particular emphasis on primary health care and increases the role of local community services centres (CLSCs) and community organizations (COs). In order to understand this process as experienced by COs, the present exploratory study was conducted during the summer and fall of 1996. We targeted 12 COs, 4 CLSCs, the Quebec Federation of CLSCs, and the Montreal CLSC Working Group. Semi-structured group interviews and CO documents were used as sources of information. Most participants believe in the need for change but feel that the strategies and implementation have been mismanaged. COs are feeling the pressure to professionalize and specialize current and future services. The "social economy" appears to be gaining momentum in the health sector.

Community Health Services↗
PubMed2003

Bottom-up control of carabid beetle communities in early successional wetlands: mediated by vegetation structure or plant diversity?

Two hypotheses of bottom-up control that predict that the species richness of Carabidae will depend either on the taxonomic diversity of plants ("taxonomic diversity hypothesis") or on the structural heterogeneity of the vegetation ("structural heterogeneity hypothesis") were tested. Plant species were classified into nine plant structural groups through cluster analysis of morphological traits (e.g. total height) at 30 early successional temporary wetlands in the east-German agricultural landscape. In a linear regression analysis, the heterogeneity of vegetation structures explained 55% of the variation in carabid beetle diversity. According to a partial correlation analysis, plant taxonomic diversity did not have a significant effect, consistent with the "structural heterogeneity hypothesis," and contradicting previous studies which concluded that plant taxonomic diversity would be the most important factor in early successional habitats. An experimental study was used to test hypotheses on the processes underlying this bottom-up control by vegetation structure: the "hunting efficiency hypothesis," the "enemy-free space hypothesis," and the "microhabitat specialization hypothesis." The composition of plant structural groups in 15 vegetation plots (1 m(2)) was manipulated, creating a gradient from dense vegetation to open plots. Subsequent pitfall catches revealed significant differences in the activity-abundances of the carabid species. Large species preferred dense vegetation plots, consistent with the enemy-free space hypothesis that large species are more vulnerable to predation on the open plots and prefer dense vegetation to escape from natural enemies. The results indicate that bottom-up control is not mediated only by plant taxonomic or functional group diversity and that vegetation structures may be more important than previously suggested.

Agriculture↗
PubMed1981

Lipid-tail group dependent structure of the fd gene 8 protein.

Using circular dichroism several laboratories have shown that the fd coat protein can assume three distinct conformations depending on the conditions. We have reinvestigated these three conformations using laser Raman spectroscopy and the quantitative estimates of alpha-helix by Raman agree fairly well with the earlier estimates obtained by CD. In addition, we have studied in more detail the conditions governing the 3 conformations. To our surprise, the nature f the lipid tail group seems to be the determining factor for two of the conformations. A lipid tail group dependence of protein structure is without precedent and has potential consequences for the assembly of filamentous phages as well as for the structure and function of cell membranes.

Circular Dichroism↗
PubMed2006

Diversity in in-group bias: structural factors, situational features, and social functions.

Four experiments addressed the different forms and functions of in-group bias in different contexts. The authors proposed 2 functions: an identity-expressive function and an instrumental function (or promotion of positive social change). The authors manipulated status differentials, the stability of these differences, and the communication context (intra- vs. intergroup) and measured in-group bias and both functions. As predicted, identity expression via in-group bias on symbolic measures was most important for stable, high-status groups. By contrast, material in-group bias for instrumental motives was most prevalent in unstable, low-status groups but only when communicating with in-group members. This latter effect illustrates the strategic adaptation of group behavior to audience (i.e., displaying in-group bias may provoke the out-group and be counterproductive in instrumental terms). Stable, low-status groups displayed more extreme forms of in-group bias for instrumental reasons regardless of communication context (i.e., they had nothing to lose). Results are discussed in terms of a contextual-functional approach to in-group bias.

Adult↗
PubMed1999

Treatment of hospitalized patients with complicated gram-positive skin and skin structure infections: two randomized, multicentre studies of quinupristin/dalfopristin versus cefazolin, oxacillin or vancomycin. Synercid Skin and Skin Structure Infection Group.

Quinupristin/dalfopristin (Synercid), the first injectable streptogramin antibiotic available for the treatment of complicated gram-positive skin and skin structure infections, was compared with standard comparators (cefazolin, oxacillin or vancomycin) in one USA and one international trial. These two randomized, open-label trials of virtually identical design enrolled a total of 893 patients (450 quinupristin/dalfopristin, 443 comparator). The majority of patients had erysipelas, traumatic wound infection or clean surgical wound infection. Staphylococcus aureus was the most frequently isolated pathogen in both treatment groups and polymicrobial infection was more common in the quinupristin/dalfopristin group than in the comparator group. The clinical success rate (cure plus improvement) in the clinically evaluable population was equivalent between the two treatment groups (68.2% quinupristin/dalfopristin, 70.7% comparator; 95% CI, -10.1, 5.1) despite a shorter mean duration of treatment for quinupristin/dalfopristin patients. In the bacteriologically evaluable population, by-patient and by-pathogen bacteriological eradication rates were somewhat lower for quinupristin/dalfopristin (65.8% and 66.6%, respectively) than for the comparator regimens (72.7% and 77.7%, respectively). The lower bacteriological response rates in the quinupristin/dalfopristin group were, in part, due to a higher rate of polymicrobial infections and a higher incidence of patients classified as clinical failure, a category which included premature discontinuation of treatment because of local venous adverse events. The bacteriological eradication rate for quinupristin/dalfopristin was higher in monomicrobial infections than in polymicrobial infections (72.6% versus 63.3%, respectively), whereas the corresponding rate for the comparator regimens was lower for monomicrobial infections than polymicrobial infections (70.8% versus 83.1%). This finding was not unexpected, since the spectrum of quinupristin/dalfopristin is focused on gram-positive pathogens and additional antibiotics to treat gram-negative bacteria were not required per protocol. The systemic tolerability of both treatment regimens was qualitatively similar. A higher rate of drug-related venous adverse events was reported for quinupristin/dalfopristin (66.2%) than for the comparator regimen (28.4%). Premature discontinuation of study drug was primarily due to adverse clinical events for quinupristin/dalfopristin (19.1%), whereas the most common reason for discontinuation among those receiving the comparator regimens was treatment failure (11.5%). Quinupristin/dalfopristin is an effective alternative for the treatment of hospitalized patients with complicated skin and skin structure infections due to quinupristin/ dalfopristin-susceptible gram-positive organisms, including methicillin- and erythromycin-resistant S. aureus.

Adolescent↗
PubMed1976

Human tryptophan transfer ribonucleic acid synthetase. Composition, function of thiol groups, and structure of thiol peptides.

Human tryptophanyl-tRNA synthetase resembles its counterpart in Escherichia coli in quaternary structure (alpha2), but differs in molecular weight, amino acid composition, the number of thiol groups, and the relationship of the thiol groups to enzyme activity. Nevertheless, one of the thiol groups resides in a heptapeptide sequence homologous to a heptapeptide sequence containing a thiol group in the E. coli enzyme. Each subunit of the enzyme has 6 half-cystine residues, and four thiol groups are readily titrated with 5,5'-dithiobis(2-nitrobenzoic acid). Titration of these four thiol groups inactivates the enzyme, and the inactivation is partially reversible by reduction with dithiothreitol. One thiol group reacts rapidly unless L-tryptophan, ATP, and Mg2+ are present together.

Adenosine Triphosphate↗
PubMed2006

Quantum chemical treatment of large nanotubes via use of line group symmetry: structural preferences of magnesium dichloride nanotubes.

Nanotubes with diameters in the magnitude of 10 nm can be treated by quantum chemical methods, made possible by utilization of line group symmetries. The methodology presented here is applied for magnesium dichloride nanotubes. The structural preferences of MgCl2 nanotubes are strongly dependent on the tube diameter. The rolled layer of a crystalline sheet becomes favorable above a diameter of 3.4 nm, below which alternative stable coordination modes dominate. Application of the methodology for other nanotubular compounds, including multiwalled nanotubes, is expected to be straightforward.

Journal Article↗
PubMed1994

Human enteric Caliciviridae: a new prevalent small round-structured virus group defined by RNA-dependent RNA polymerase and capsid diversity.

Sequence comparison of the RNA-dependent RNA polymerases of small round-structured viruses (SRSVs) from 10 recent U.K. outbreaks of gastroenteritis revealed significant genetic variation. Computer analyses indicated that these viruses can be divided into two discrete groups. SRSV group I contains the previously characterized antigenic type 1 Norwalk and type 3 Southampton viruses. The amino acid sequences of the RNA polymerase, capsid and ORF3 of these two viruses are relatively similar (about 92%, 69% and 72% amino acid identity, respectively). A representative member of group II SRSVs, Bristol virus, was subjected to a detailed genetic analysis. Bristol virus is a recent antigenic type 2 isolate from a U.K. hospital outbreak of gastroenteritis. Using a single clinical sample the 3'-terminal 3881 nucleotide cDNA sequence [excluding the poly(A) tail] of this virus was determined. Analysis of the sequence revealed significant differences from those of group I viruses with the RNA polymerase region, capsid and ORF3 showing only about 62%, 43% and 30% amino acid identity respectively with the equivalent proteins of the Norwalk and Southampton viruses. These data suggest that the morphologically identical SRSVs belong to at least two genetically distinct groups.

Amino Acid Sequence↗