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61.
Jessica A. Hartmann Marieke Wichers Claudia Menne-Lothmann Ingrid Kramer Wolfgang Viechtbauer Frenk Peeters Koen R. J. Schruers Alex L. van Bemmel Inez Myin-Germeys Philippe Delespaul Jim van Os Claudia J. P. Simons 《PloS one》2015,10(6)
Objectives
Positive affect (PA) plays a crucial role in the development, course, and recovery of depression. Recently, we showed that a therapeutic application of the experience sampling method (ESM), consisting of feedback focusing on PA in daily life, was associated with a decrease in depressive symptoms. The present study investigated whether the experience of PA increased during the course of this intervention.Design
Multicentre parallel randomized controlled trial. An electronic random sequence generator was used to allocate treatments.Settings
University, two local mental health care institutions, one local hospital.Participants
102 pharmacologically treated outpatients with a DSM-IV diagnosis of major depressive disorder, randomized over three treatment arms.Intervention
Six weeks of ESM self-monitoring combined with weekly PA-focused feedback sessions (experimental group); six weeks of ESM self-monitoring combined with six weekly sessions without feedback (pseudo-experimental group); or treatment as usual (control group).Main outcome
The interaction between treatment allocation and time in predicting positive and negative affect (NA) was investigated in multilevel regression models.Results
102 patients were randomized (mean age 48.0, SD 10.2) of which 81 finished the entire study protocol. All 102 patients were included in the analyses. The experimental group did not show a significant larger increase in momentary PA during or shortly after the intervention compared to the pseudo-experimental or control groups (χ2 (2) =0.33, p=.846). The pseudo-experimental group showed a larger decrease in NA compared to the control group (χ2 (1) =6.29, p=.012).Conclusion
PA-focused feedback did not significantly impact daily life PA during or shortly after the intervention. As the previously reported reduction in depressive symptoms associated with the feedback unveiled itself only after weeks, it is conceivable that the effects on daily life PA also evolve slowly and therefore were not captured by the experience sampling procedure immediately after treatment.Trial Registration
Trialregister.nl/trialreg/index.asp. NTR1974 相似文献62.
Holst J Watson S Lord MS Eamegdool SS Bax DV Nivison-Smith LB Kondyurin A Ma L Oberhauser AF Weiss AS Rasko JE 《Nature biotechnology》2010,28(10):1123-1128
Surprisingly little is known about the effects of the physical microenvironment on hemopoietic stem and progenitor cells. To explore the physical effects of matrix elasticity on well-characterized primitive hemopoietic cells, we made use of a uniquely elastic biomaterial, tropoelastin. Culturing mouse or human hemopoietic cells on a tropoelastin substrate led to a two- to threefold expansion of undifferentiated cells, including progenitors and mouse stem cells. Treatment with cytokines in the presence of tropoelastin had an additive effect on this expansion. These biological effects required substrate elasticity, as neither truncated nor cross-linked tropoelastin reproduced the phenomenon, and inhibition of mechanotransduction abrogated the effects. Our data suggest that substrate elasticity and tensegrity are important mechanisms influencing hemopoietic stem and progenitor cell subsets and could be exploited to facilitate cell culture. 相似文献
63.
Max Haring Rechien Bader Marieke Louwers Anne Schwabe Roel van Driel Maike Stam 《The Plant journal : for cell and molecular biology》2010,63(3):366-378
Paramutation is the transfer of epigenetic information between alleles that leads to a heritable change in expression of one of these alleles. Paramutation at the tissue‐specifically expressed maize (Zea mays) b1 locus involves the low‐expressing B′ and high‐expressing B‐I allele. Combined in the same nucleus, B′ heritably changes B‐I into B′. A hepta‐repeat located 100‐kb upstream of the b1 coding region is required for paramutation and for high b1 expression. The role of epigenetic modifications in paramutation is currently not well understood. In this study, we show that the B′ hepta‐repeat is DNA‐hypermethylated in all tissues analyzed. Importantly, combining B′ and B‐I in one nucleus results in de novo methylation of the B‐I repeats early in plant development. These findings indicate a role for hepta‐repeat DNA methylation in the establishment and maintenance of the silenced B′ state. In contrast, nucleosome occupancy, H3 acetylation, and H3K9 and H3K27 methylation are mainly involved in tissue‐specific regulation of the hepta‐repeat. Nucleosome depletion and H3 acetylation are tissue‐specifically regulated at the B‐I hepta‐repeat and associated with enhancement of b1 expression. H3K9 and H3K27 methylation are tissue‐specifically localized at the B′ hepta‐repeat and reinforce the silenced B′ chromatin state. The B′ coding region is H3K27 dimethylated in all tissues analyzed, indicating a role in the maintenance of the silenced B′ state. Taken together, these findings provide insight into the mechanisms underlying paramutation and tissue‐specific regulation of b1 at the level of chromatin structure. 相似文献
64.
D Williamson I J McLennan A Bax M P Gamcsik J D Glickson 《Journal of biomolecular structure & dynamics》1990,8(2):375-398
Two-dimensional NMR experiments--one bond 1H-13C correlation spectroscopy and heteronuclear multiple bond correlation spectroscopy, both performed in the reverse detection mode--have been employed to unambiguously assign all of the 13C resonances of the antibiotic bleomycin and its zinc(II) complex. Previous 1H resonance assignments of bleomycin (Chen et al. (1977) Biochemistry 16, 2731-2738) were confirmed on the basis of homonuclear Hartmann-Hahn and homonuclear COSY experiments. The 13C assignments differ substantially from those previously obtained by other investigators (Naganawa et al., (1977) J. Antibiot. 30, 388-396; Dabrowiak et al., (1978) Biochemistry 17, 4090-4096) but are in agreement with those reported by Akkerman et al. (1988) (Magn. Reson. Chem. 26, 793-802). The more recent study employed similar two-dimensional correlation experiments (performed in the direct detection mode) in conjunction with attached proton tests. Their study often required model compound data to identify carbonyls adjacent to aliphatic moieties. Previous 13C NMR studies of the structure, pH titration, and molecular dynamics of bleomycin and its zinc complex have been reinterpreted in terms of the revised assignments. 相似文献
65.
V Sklenár J Kypr A Bax G Zon M Vorlícková 《International journal of biological macromolecules》1989,11(5):273-277
DNA fragments d(TATATATA) and d(TATATA) were studied in low-salt aqueous solutions and found to coexist in more than one conformer. 1H-n.m.r. demonstrates that single-stranded and double-stranded states are involved in the conformational coexistence. Circular dichroism spectroscopy indicates a global B-DNA stacking of bases in the fragments. 31P-n.m.r. resonances of the TpA and ApT phosphodiester bonds are substantially separated in the spectra of both d(TATATATA) and d(TATATA) duplexes to suggest an alternating architecture of their backbones. In fact, the oligonucleotide duplexes are much more alternating than the corresponding polynucleotide under the same solution conditions. The alternating character of the d(TATATATA) double helix is further enhanced in molar caesium fluoride solutions. The oligonucleotide isomerization into X-DNA is, however, accompanied by gel formation, which makes high resolution n.m.r. measurements impossible. 相似文献
66.
Vossen M Edelstein J Majzoub RK Maldonado C Perez-Abadia G Voor MJ Orhun H Tecimer T Francois C Kon M Barker JH 《Plastic and reconstructive surgery》2005,115(2):529-538
Although vascularized bone and joint allotransplantation is a promising new treatment option for reconstructing large bone defects, the need for immunosuppressive agents to prevent rejection in these procedures poses a major problem. This problem stems from the fact that several of these agents can cause harmful side effects, such as alterations in bone quality and healing. Therefore, the purpose of this study was to determine what effect the commonly used immunosuppressant regimen cyclosporine A-based combination therapy has on bone quality and healing. In 10 pigs, vascularized bone allografts with skin and muscle components (osteomyocutaneous free flaps) were transplanted from size-matched donor animals. Recipient animals received oral cyclosporine A/mycophenolate mofetil/prednisone therapy for 90 days. Bone quality was studied before and after transplantation by measuring the bone's acoustic velocity and density and calculating the bone's elastic coefficient. Bone healing was assessed using radiographic analysis. Four animals were lost as a result of graft rejection or immunosuppression-related complications before the 90-day endpoint of the study. Although bone specimens taken from the six animals that completed the 90-day protocol had histological signs of rejection, they all seemed to have normal bone healing. Posttransplant bone density values were significantly decreased (p < 0.05) (1544.7 +/- 47.5 kg/m3) as compared with pretransplant values (1722.7 +/- 44.1 kg/m3). Results of the acoustic velocity and elastic coefficients measurements showed a significant decrease (p < 0.05) in posttransplant values (from 3503.0 +/- 165.1 meters/sec to 2963.0 +/- 54.6 meters/sec and from 21.6 +/- 2.2 GPa to 13.6 +/- 0.5 GPa, respectively), indicating diminished bone quality. The findings indicate that cyclosporine A/mycophenolate mofetil/prednisone combination therapy is ineffective in preventing bone rejection, that it decreases bone quality, and that it is associated with systemic toxicity, suggesting that this immunosuppressive regimen at the doses used in this study is not ideal for vascularized bone allotransplantation procedures. 相似文献
67.
Marieke J. Bloemink Aileen F. Knowles Michael A. Geeves Sanford I. Bernstein 《Journal of molecular biology》2009,389(4):707-1122
We investigated the biochemical and biophysical properties of one of the four alternative regions within the Drosophila myosin catalytic domain: the relay domain encoded by exon 9. This domain of the myosin head transmits conformational changes in the nucleotide-binding pocket to the converter domain, which is crucial to coupling catalytic activity with mechanical movement of the lever arm. To study the function of this region, we used chimeric myosins (IFI-9b and EMB-9a), which were generated by exchange of the exon 9-encoded domains between the native embryonic body wall (EMB) and indirect flight muscle isoforms (IFI). Kinetic measurements show that exchange of the exon 9-encoded region alters the kinetic properties of the myosin S1 head. This is reflected in reduced values for ATP-induced actomyosin dissociation rate constant (K1k+2) and ADP affinity (KAD), measured for the chimeric constructs IFI-9b and EMB-9a, compared to wild-type IFI and EMB values. Homology models indicate that, in addition to affecting the communication pathway between the nucleotide-binding pocket and the converter domain, exchange of the relay domains between IFI and EMB affects the communication pathway between the nucleotide-binding pocket and the actin-binding site in the lower 50-kDa domain (loop 2). These results suggest an important role of the relay domain in the regulation of actomyosin cross-bridge kinetics. 相似文献
68.
J L Hopkins R Betageri K A Cohen M J Emmanuel C R Joseph P M Bax P V Pallai M T Skoog 《Journal of biochemical and biophysical methods》1991,23(2):107-113
The 3C protease encoded by human rhinovirus type 2 catalyzes with equal efficiency cleavage of a peptide substrate with or without a fluorescein label attached to the amino acid at the P7' position. Substrates Ac-MEALFQGPLQYKDL-NH2 and MEALFQGPLQYKE(fluorescein)L are hydrolyzed with values of Vmax/KM of 970 M-1 s-1 and 1100 M-1 s-1, respectively. With the labeled substrate, HPLC achieves separation of substrate and product in 2.5 min. Separation in as little as 12 s is feasible. Fluorescein was derivatized so that it could be incorporated into peptides using automated solid-phase peptide synthesis. 相似文献
69.
Summary A simple E.COSY type technique is described for measurement of two-bond JCOH coupling constants in proteins that are uniformly enriched with13C. The method has been used to measure2JCOH for 132 residues in the proteins calmodulin and staphylococcal nuclease having non-overlapping H–C correlations. Measured2JCOH coupling constants fall in the 0 to –9.5 Hz range. A separate experiment, measuring the accuracy of these values, indicates a root-mean-square error of 1 Hz. Comparison of the J couplings with the dihedral back bone angles from crystallographic studies confirms a weak but statistically significant correlation between the dihedral angle and the magnitude of2JCOH, but also indicates that parameters other than have a significant effect on the value of the coupling. 相似文献
70.
Alex van Belkum Ren Bax Piet J. C. van der Straaten Wim G. V. Quint Etel Veringa 《Journal of microbiological methods》1994,20(4):235-247
Staphylococcus aureus isolates (n = 126), collected during two different periods from patients hospitalised in pediatric wards, were analysed using polymerase chain reaction (PCR) mediated genotyping. These isolates were compared with 29 isolates from individuals attending the out-patient clinic of the same hospital and 13 isolates from pediatric hospital personnel. Within a group of 99 isolates gathered from 48 individuals during surveillance period I, 22 distinct genotypes were identified by application of two PCR assays. Among the 58 isolates collected in surveillance period II from pediatric and out-clinic patients, 25 genotypes were detected by a single PCR assay only. Based on these results it was demonstrated that patients can be colonised with multiple strains that may persist in a certain anatomical location for prolonged periods of time. It is shown that persistence of a S. aureus strain in a pediatric ward can be deduced from the PCR genotyping studies. As such PCR can be used for longitudinal monitoring of bacterial infections in hospital departments, analysis of patient-to-patient and personnel-to-patient transmission and for detection of genetic variation in general in S. aureus. Also, isolate-specific DNA probes can be generated for S. aureus by PCR genotyping. The probes can be used for the recognition of re-emerging S. aureus epidemics. 相似文献