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PubMedDate not supplied

Components of Type A, hostility, and anger-in: relationship to angiographic findings.

Previous research has linked the Type A coronary-prone behavior pattern to angiographically documented severity of coronary atherosclerosis (CAD). The present study sought through component scoring of the Type A Structured Interview (SI) to determine what elements of the multidimensional Type A pattern are related to coronary disease severity in a selected group of patients with minimal or severe CAD. Multivariate analyses controlling for the major risk factors showed no relationship between global Type A and extent of disease. Of all attributes measured, only Potential for Hostility and Anger-In were significantly and positively associated with the disease severity, including angina symptoms and number of myocardial infarctions. Further analysis revealed that Potential for Hostility and Anger-In were interactive in their association, such that Potential for Hostility was associated with disease endpoints only for patients who were high on the Anger-In dimension. These findings support previous research in suggesting that anger and hostility may be the critical aspects of the Type A pattern in predisposing individuals to risk of CAD.

Anger↗
PubMed1985

Immunoelectron microscopic study on the cross-reactivity of antibodies to adult T-cell leukemia-associated antigens in human and monkey sera.

The cross-reactivity of antibodies to adult T-cell leukemia (ATL)-associated antigens (ATLA) in human and monkey sera was investigated by indirect immunoperoxidase and immunoferritin methods using a human cell line (MT-2) carrying a type C virus (HTLV), two monkey cell lines (Si-1 and Si-3) carrying HTLV, and a monkey cell line (Si-2) carrying a type C virus isolated from an anti-ATLA-positive monkey. Anti-ATLA-positive but not-negative human and monkey sera gave positive immunoperoxidase reaction with all four virus-positive cell lines when studied by light microscopy. Electron microscopic findings revealed ferritin or peroxidase labeling of virus particles and plasma membranes of these four cell lines with antibody-positive but not-negative human and monkey sera. These results clearly indicate the cross-reactivity of anti-ATLA antibodies in human and monkey sera at light and electron microscopic levels, and the presence of antigenic determinants common to the surface of type C virus particles of human and monkey origin.

Animals↗
PubMed1982

Propranolol medication among coronary patients: relationship to type A behavior and cardiovascular response.

The present correlational study compared behavioral and psychophysiological characteristics of coronary patients who were either medicated or not medicated with the beta-adrenergic blocking drug propranolol. Eighty-eight patients were given a structured Type A interview (SI) and a history quiz while heart rate and blood pressure were monitored. Data were analyzed controlling for age, sex, extent of coronary artery disease, and history of angina. Results indicated that patients taking propranolol (n = 65) were significantly lower in intensity of Type A behavior than patients not taking propranolol (n = 23). No effects were obtained for patients medicated or not medicated with diuretics, nitrates, or other CNS active drugs. Propranolol patients also showed lesser heart rate and rate-pressure product responses to the interview, but did not differ in blood pressure responses. Components of Type A which were lower in propranolol patients included speech stylistics (loud/explosive, rapid/accelerated, potential for hostility). Content of responses to the SI and scores on the Jenkins Activity Survey did not differ between the groups. An explanation for these results is offered in terms of the effects of propranolol on peripheral sympathetic responses, and evidence for a physiological substrate for Type A behavior. A conceptualization of the Type A pattern in terms of cognitive and physiological components is advanced, and implications for clinical intervention are discussed.

Adult↗
PubMed2004

Developments in the synthesis of LiF:Mg,Cu,Na,Si TL material.

A procedure for synthesis of the highly sensitive pellet-type LiF:Mg,Cu,Na,Si thermoluminescent (TL) detector has been newly developed. It was found that the optimum concentrations of dopants for a pellet-type LiF:Mg,Cu,Na,Si TL detector were found to be Mg: 0.2 mol %, Cu: 0.05 mol %, Na: 0.9 mol%, and Si: 0.9 mol%. The TL sensitivity of this new detector was about 30 times higher than that of the TLD-100 by light integration measurements. Reusability study of the detector was carried out for 10 cycles. The results show that the coefficients of variation for each detector separately did not exceed 0.016, and that for all 10 detectors collectively was 0.0054.

Copper↗
PubMed1994

Standardized microtiter assay for determination of syncytium-inducing phenotypes of clinical human immunodeficiency virus type 1 isolates.

A standardized assay in 96-well microtiter plates for syncytium-inducing (SI) human immunodeficiency virus type 1 phenotype detection using MT-2 cells has been developed. SI variants were found in 67% of the patients with advanced human immunodeficiency virus disease. The occurrence of the SI phenotype increased with lower CD4+ counts. There was no association between p24 antigenemia and the SI phenotype.

Blood Preservation↗
PubMed2002

Transcriptional regulation of the type I myosin heavy chain promoter in inactive rat soleus.

Chronic muscle inactivity with spinal cord isolation (SI) decreases expression of slow type I myosin heavy chain (MHC) while increasing expression of the faster MHC isoforms, primarily IIx. The purpose of this study was to determine whether type I MHC downregulation in the soleus muscle of SI rats is regulated transcriptionally and to identify cis-acting elements or regions of the rat type I MHC gene promoter involved in this response. One week of SI significantly decreased in vivo activity of the -3500-, -408-, -299-, -215-, and -171-bp type I MHC promoters. The activity of all tested deletions of the type I MHC promoter, relative to the human skeletal alpha-actin promoter, were significantly reduced in the SI soleus, except activity of the -171-bp promoter, which increased. Mutation of the betae3 element (-214/-190 bp) in the -215- and -408-bp promoters and deletion of this element (-171-bp promoter) attenuated type I downregulation with SI. Gel mobility shift assays demonstrated a decrease in transcription enhancer factor-1 binding to the betae3 element with SI, despite an increase in total binding to this region. These results demonstrate that type I MHC downregulation with SI is transcriptionally regulated and suggest that interactions between transcription enhancer factor-1 and the betae3 element are likely involved in this response.

Animals↗
PubMed1984

Psychophysiology of type A behavior pattern: a critical analysis.

Based on an analysis of 45 studies recently reported in the literature and data from a psychophysiological investigation, the hypothesized physiological mechanisms underlying Type A behavior and the methods used to determine Type A behavior (e.g., Structured Interview, SI, and the Jenkins Activity Survey, JAS) are tested. After determining behavior type with both the SI and JAS, subjects (N = 58 physical-education students) participated in a laboratory/field experiment with two replications consisting of the following conditions: (1) rest, (2) mental arithmetic, (3) reaction time test, (4) preparing and giving a speech, (5) Cold Pressor Test, (6) bicycle ergometric exercise, and (7) 1000 m run. Blood pressure, heart rate, stroke volume, cardiac output, ventricular ejection time, pulse volume amplitude, pulse transit time, pulse wave velocity, electrodermal activity, respiratory volume, oxygen uptake, and uric catecholamine levels were measured. Results of the analysis of the literature indicate that, with the exception of change scores on systolic blood pressure, mean differences on the physiological measures exhibited by Type A and B men are primarily not significant. The Structured Interview shows only a modest inter-rater reliability. The Jenkins Activity Survey demonstrates relatively low stability upon retest and fails to show sufficient internal consistency. Correlations between these measures are low. No consistent differences on physiological measures could be found in our subjects based on behavior type (according to SI or JAS criteria), although the challenging conditions were selected to elicit Type A behavior. Four our data, differences between Types A and B were also not found for systolic blood pressure, regardless of which behavioral assessment method was employed.

Adult↗
PubMed2001

Evaluation of Surface Enthalpy of Porous Aluminosilicates of the MCM-41 Type Using Immersional Calorimetry: Effect of the Pore Size and Framework Si:Al Ratio.

Surface properties of porous aluminosilicates of the MCM-41 type have been tested by immersional calorimetry. Two series of materials, referred to as SiAlxCn, where x is the Si : Al mole ratio and n the chain length of the surfactant template, having (1) x=32 and n=8, 12, 14, 16, 18 and (2) n=14 and x=8, 32, infinity, were used. The results of thermogravimetric analysis on these samples served to evaluate the surface density of hydroxyl groups. This parameter is rather sensitive to the pore size than to the aluminium content in the solid matrix. Based on the experimentally measured enthalpies of immersion in n-heptane, water, and formamide per unit BET specific surface area, estimates could be made of the apolar, Lewis acid, and Lewis base contributions to the total surface enthalpy of MCM-41 materials. The samples studied have a predominant surface acidic character, which is markedly enhanced by incorporating aluminium into the silica matrix. Surface acidity is also modified by changes in the porous structure, although the trends are less noticeable here. Nevertheless, the total surface enthalpy of MCM-41 aluminosilicates appears to be small in comparison with typical inorganic oxides, such as silica or alumina. Copyright 2001 Academic Press.

Journal Article↗
PubMed2002

Sucrase is an intramolecular chaperone located at the C-terminal end of the sucrase-isomaltase enzyme complex.

The sucrase-isomaltase enzyme complex (pro-SI) is a type II integral membrane glycoprotein of the intestinal brush border membrane. Its synthesis commences with the isomaltase (IM) subunit and ends with sucrase (SUC). Both domains reveal striking structural similarities, suggesting a pseudo-dimeric assembly of a correctly folded and an enzymatically active pro-SI. The impact of each domain on the folding and function of pro-SI has been analyzed by individual expression and coexpression of the individual subunits. SUC acquires correct folding, enzymatic activity and transport competence and is secreted into the external milieu independent of the presence of IM. By contrast, IM persists as a mannose-rich polypeptide that interacts with the endoplasmic reticulum resident molecular chaperone calnexin. This interaction is disrupted when SUC is coexpressed with IM, indicating that SUC competes with calnexin for binding of IM. The interaction between SUC and the membrane-anchored IM leads to maturation of IM and blocks the secretion of SUC into the external milieu. We conclude that SUC plays a role as an intramolecular chaperone in the context of the pro-SI protein. To our knowledge all intramolecular chaperones so far identified are located at the N-terminal end. SUC is therefore the first C-terminally located intramolecular chaperone in mammalian cells.

Amino Acid Substitution↗
PubMed2004

CXCR4-dependent infection of CD8+, but not CD4+, lymphocytes by a primary human immunodeficiency virus type 1 isolate.

We recently isolated from an infant an X4-syncytium-inducing (SI) human immunodeficiency virus type 1 (HIV-1) variant (92US143-T8) that was able to infect CD8+ lymphocytes independently of CD4. Although it was CD4 independent, the 92US143-T8 isolate also maintained the ability to infect CD4+ cells. In the present study, we investigated the role of CXCR4 in the infection of CD4+ and CD8+ cells by this primary isolate. The expression of CXCR4 was down modulated in CD8+ lymphocytes after infection with the 93US143-T8 isolate. Infection of CD8+ lymphocytes by the 93US143-T8 isolate was prevented by treatment with AMD3100, a specific antagonist for CXCR4, indicating CXCR4-dependent infection. Interestingly, AMD3100 treatment had no inhibitory role in the infection of purified CD4+ lymphocytes by the same isolate. Furthermore, AMD3100 treatment failed to prevent infection of known CD4+ CXCR4+ T-cell lines (MT-2 and CEM) by the 93US143-T8 isolate. In fact, virus replication in the CD4+ cells was often enhanced in the presence of AMD3100. Viruses produced from the infected CD4+ cells in the presence of AMD3100 maintained an unchanged envelope genotype and an SI phenotype. For the first time, these results provide evidence of CXCR4-dependent infection of CD8+ lymphocytes by a primary HIV-1 isolate. This study also shows a different mode of infection for the CD4+ and CD8+ lymphocytes by the same HIV-1 variant. Finally, our findings suggest that a more careful evaluation is necessary before the random use of AMD3100 as a new entry inhibitor in patients harboring SI HIV-1 strains.

CD4-Positive T-Lymphocytes↗
PubMed2001

Nb4Pd0.5ZSb2 (Z = Cr, Fe, Co, Ni, Si): the first ordered quaternary variants of the W5Si3-type structure.

A family of quaternary (or pseudoquaternary) antimonides Nb4Pd0.5ZSb2 (Z = Cr, Fe, Co, Ni, Si) containing up to three transition metals in an ordered arrangement has been prepared by reactions of the elements. These antimonides are isostructural, crystallizing as substitutional variants of the W5Si3-type structure (tetragonal, space group -I4/mcm, Z = 4) with unit cell parameters a = 10.4407(3) A and c = 5.0020(2) A for Nb4Pd0.5Cr0.28(3)Si0.72Sb2, a = 10.4825(6) A and c = 4.9543(3) A for Nb4Pd0.5FeSb2, a = 10.4603(5) A and c = 4.9457(3) A for Nb4Pd0.5CoSb2, a = 10.4332(7) A and c = 4.9649(3) A for Nb4Pd0.5Ni0.78(1)Sb2, and a = 10.3895(10) A and c = 4.9634(4) A for Nb4Pd0.5SiSb2. They are distinguished by the filling of interstitial Z atoms into the centers of Nb8 square antiprismatic clusters that are linked by PdSb4 tetrahedra. The Nb8 square antiprisms share opposite square faces to form one-dimensional chains along the c axis so that Z-Z bonding distances of approximately 2.5 A result. Extended Hückel band structure calculations were carried out to interpret the homo- and heteroatomic metal-metal interactions in the structure. The resistivity of one member, Nb4Pd0.5SiSb2, was measured, indicating metallic behavior.

Journal Article↗
PubMed2002

Framework engineering by anions and porous functionalities of Cu(II)/4,4'-bpy coordination polymers.

A combination of framework-builder (Cu(II) ion and 4,4'-bipyridine (4,4'-bpy) ligand) and framework-regulator (AF(6) type anions; A = Si, Ge, and P) provides a series of novel porous coordination polymers. The highly porous coordination polymers ([Cu(AF(6))(4,4'-bpy)(2)].8H(2)O)(n)(A = Si (1a.8H(2)O), Ge (2a.8H(2)O)) afford robust 3-dimensional (3-D), microporous networks (3-D Regular Grid) by using AF(6)(2-) anions. The channel size of these complexes is ca. 8 x 8 A(2) along the c-axis and 6 x 2 A(2) along the a- or b-axes. When compounds 1a.8H(2)O or 2a.8H(2)O were immersed in water, a conversion of 3-D networks (1a.8H(2)O or 2a.8H(2)O) to interpenetrated networks ([Cu(4,4'-bpy)(2)(H(2)O)(2)].AF(6))(n)(A = Si (1b) and Ge (2b)) (2-D Interpenetration) took place. This 2-D interpenetrated network 1b shows unique dynamic anion-exchange properties, which accompany drastic structural conversions. When a PF(6)(-) monoanion instead of AF(6)(2)(-) dianions was used as the framework-regulator with another co-counteranion (coexistent anions), porous coordination polymers with various types of frameworks, ([Cu(2)(4,4'-bpy)(5)(H(2)O)(4)].anions.2H(2)O.4EtOH)(n)(anions = 4PF(6)(-) (3.2H(2)O.4EtOH), 2PF(6)(-) + 2ClO(4)(-) (4.2H(2)O.4EtOH)) (2-D Double-Layer), ([Cu(2)(PF(6))(NO(3))(4,4'-bpy)(4)].2PF(6).2H(2)O)(n)(5.2PF(6).2H(2)O) (3-D Undulated Grid), ([Cu(PF(6))(4,4'-bpy)(2)(MeCN)].PF(6).2MeCN)(n)(6.2MeCN) (2-D Grid), and ([Cu(4,4'-bpy)(2)(H(2)O)(2)].PF(6).BF(4))(n) (7) (2-D Grid), were obtained, where the three modes of PF(6)(-) anions are observed. 5.2PF(6).2H(2)O has rare PF(6)(-) bridges. The PF(6)(-) and NO(3)(-) monoanions alternately link to the Cu(II) centers in the undulated 2-D sheets of [Cu(4,4'-bpy)(2)](n)() to form a 3-D porous network. The free PF(6)(-) anions are included in the channels. 6.2MeCN affords both free and terminal-bridged PF(6)(-) anions. 3.2H(2)O.4EtOH, 4.2H(2)O.4EtOH, and 7 bear free PF(6)(-) anions. All of the anions in 3.2H(2)O.4EtOH and 4.2H(2)O.4EtOH are freely located in the channels constructed from a host network. Interestingly, these Cu(II) frameworks are rationally controlled by counteranions and selectively converted to other frameworks.

Journal Article↗
PubMed1999

Expression of cell cycle markers in colorectal carcinoma: superiority of cyclin A as an indicator of poor prognosis.

Our aim was to analyze the relationship between the proliferative activity of cancer cells, assessed using some cell cycle markers, and clinicopathological factors in colorectal carcinoma patients. Immunostaining for Ki-67 (pan-cell cycle marker), cyclin D1 (G1-phase marker) and cyclin A (S- to G2-phase marker), and in situ hybridization for histone H3 mRNA (S-phase marker) were carried out. Immunoreactivity was evaluated semiquantitatively using a scoring system to calculate a staining index (SI). The expression of cyclin D1, histone H3 mRNA and cyclin A correlated significantly with Ki-67 antigen expression. The SIs of Ki-67, cyclin A and histone H3 mRNA were significantly higher in patients > or = 65 years of age than in those < 65. The SIs of Ki-67 and cyclin D1 in poorly differentiated adenocarcinomas were significantly higher than in the other tumor types. Furthermore, the SI of cyclin D1 in carcinomas with lymph node metastasis was higher than in carcinomas without metastasis and was higher in advanced carcinomas than early carcinomas. The overall survival was significantly lower in patients with cyclin A overexpression than in those without. Multivariate analysis indicated that cyclin A overexpression is an independent prognostic factor in patients with colorectal adenocarcinoma. Our results indicate that cyclin D1 overexpression correlates with poor adenocarcinoma differentiation and tumor progression, and cyclin A overexpression is a superior indicator of poor prognosis compared with the other cell cycle markers tested.

Adult↗
PubMed2003

The structure and stability of Si60 and Ge60 cages: a computational study.

Structural studies of fullerene-like Si(60) and Ge(60) cages using ab initio methods were augmented by density functional tight-binding molecular dynamics (DFTB-MD) simulations of finite temperature effects. Neither the perfect I(h) symmetry nor the distorted T(h) structures are true minima. The energies of both are high relative to distorted, lower symmetry minima, C(i) and T, respectively, which still preserve C(60)-type connectivity. Both Si(60) and Ge(60) favor C(i) symmetry cages in which Si and Ge vertexes exhibit either near-trigonal or pyramidal geometries. These structural variations imply significant reactivity differences between different positions. The small magnetic shielding effects (NICS) indicate that aromaticity is not important in these systems. The inorganic fullerene cages have lower stabilities compared with their carbon analogs. Si(60) is stable towards spontaneous disintegration up to 700 K according to DFTB-MD simulations, and thus has potential for experimental observation. In contrast, Ge(60) preserves its cage structure only up to 200 K.

Journal Article↗
PubMed2001

A possible solvent effect of adenosine diphosphate influences the binding of 1,N6 ethenoadenosine diphosphate to myosin from skeletal muscle.

Skeletal muscle myosin displays two independent and equivalent binding sites for 1,N6 ethenoadenosine diphosphate, with a dissociation constant of 24.7 microM. MgADP, 10 to 40 microM, behaves as a pure competitive type inhibitor (K(SI)=8-9 microM) for the binding of 1,N6 ethenoadenosine diphosphate to skeletal muscle myosin. On the contrary, the inhibition by MgADP, 0.11-1.54 mM, is neither competitive nor non-competitive nor mixed, as is revealed by the analysis with the general kinetic equation (K.J. Laidler, P.S. Bunting, The Chemical Kinetics of Enzyme Action, 2nd ed., Clarendon, Oxford, 1973, p. 94). To explain our finding we propose that MgADP operates a complex type of inhibition, acting both directly as a competitor for myosin active sites, and indirectly by perturbing the regions of the solvent near to the protein.

Acrylamide↗
PubMedDate not supplied

Effects of hostility on platelet reactivity to psychological stress in coronary heart disease patients and in healthy controls.

Previous studies have demonstrated a potential relationship between psychological stress and platelet activation, which may serve as a link between stress and myocardial infarction (MI). However, the possibility that personality traits associated with coronary heart disease may affect platelet activation has not been adequately investigated. The effect of a laboratory stressor (Type A Structured Interview (SI) and speech task) on platelet activation was assessed in 14 stable post-MI patients and 15 age-matched healthy men, using a standardized method of measuring plasma beta-thromboglobulin (BTG) levels. BTG levels were increased after the stressor (average change = 2.0 ng/ml, p = .005). Increases in BTG with stress were related to higher SI ratings of Potential for Hostility (r = .53, p = .004) and Type A behavior (r = .43, p = .02) but not to Cook-Medley-rated hostility scores. Increases in norepinephrine levels and in diastolic blood pressure were nonsignificantly related to increases in BTG levels (ps < .10), whereas increases in epinephrine levels were unrelated. Despite ceasing aspirin and other platelet inhibitors for 10 days before testing, individuals taking platelet inhibitors before the study had less change in BTG with stress (p = .05). However, after statistical adjustment for this factor, SI ratings of Potential for Hostility were still strongly related to increases in BTG with stress (adjusted r = .56, p = .002). Contrary to expectations, healthy men tended to have greater change in BTG with stress than post-MI patients (p = .06). These results indicate that acute stress increases BTG levels and that hostility is related to greater platelet reactivity, independent of any long term effects of platelet inhibition.

Coronary Disease↗
PubMedDate not supplied

Additional value of magnetic resonance with spin echo T1-weighted imaging with fat suppression in characterization of soft tissue tumors.

OBJECTIVE: The aim of the study was to describe the signal intensity (SI) behavior of soft tissue tumors (STT) on spin echo (SE) T1 weighted images (WI) with fat suppression (FS) and to assess its additional value in tissue characterization. METHODS: MRI signal characteristics of 53 histological proven STT were discussed. Signal intensity behavior of STT could be classified in 4 types, representing specific tissues or tissue components. Type 1 was defined as low SI on both SE T1-WI and SE T1-WI with FS. Type 2 was defined as high SI on both sequences. Type 3 consisted of high SI on T1-WI and low SI on T1-WI with FS. Type 4 was defined as SI comparable with SI of normal muscle on T1-WI and SI higher than normal muscle on T1-WI with FS. The additional information concerning contrast enhancement is described. RESULTS: Type 1 SI behavior was noted in fibrous lesions, in hemosiderotic components, cysts, and myxoma. Type 2 was noted in lesions containing methemoglobin or melanin. Type 3 was specific for fatty tissue. Type 4 was noted in highly cellular parts and in lesions of vascular origin. The use of SE T1-WI with FS improved lesion conspicuity on T1-WI. CONCLUSIONS: E T1-WI with FS has additional value in the characterization of fibrous and hemosiderotic parts from cellular parts of lesions. It gives more confidence in characterization of neurogenic tumors and hemangioma's. Presence of methemoglobin and melanin are clearly discriminated from fatty tissue. Tumor conspicuity and inhomogeneity evaluation is improved. The use of SE T1-WI FS not only improves tumor conspicuity, but as tumor homogeneity and SI are important parameters in staging and characterization of STT, the use of SE T1-WI with FS will certainly be helpful. This may obviate the need for gadolinium administration.

Contrast Media↗