212 research outputs found
The impact of decision aids to enhance shared decision making for diabetes (the DAD study): protocol of a cluster randomized trial
Background. Shared decision making contributes to high quality healthcare by promoting a patientcentered approach. Patient involvement in selecting the components of a diabetes medication program that best match the patient's values and preferences may also enhance medication adherence and improve outcomes. Decision aids are tools designed to involve patients in shared decision making, but their adoption in practice has been limited. In this study, we propose to obtain a preliminary estimate of the impact of patient decision aids vs. usual care on measures of patient involvement in decision making, diabetes care processes, medication adherence, glycemic and cardiovascular risk factor control, and resource utilization. In addition, we propose to identify, describe, and explain factors that promote or inhibit the routine embedding of decision aids in practice. Methods. We will be conducting a mixed-methods study comprised of a cluster-randomized, practical, multicentered trial enrolling clinicians and their patients (n = 240) with type 2 diabetes from rural and suburban primary care practices (n = 8), with an embedded qualitative study to examine factors that influence the incorporation of decision aids into routine practice. The intervention will consist of the use of a decision aid (Statin Choice and Aspirin Choice, or Diabetes Medication Choice) during the clinical encounter. The qualitative study will include analysis of video recordings of clinical encounters and in-depth, semi-structured interviews with participating patients, clinicians, and clinic support staff, in both trial arms. Discussion. Upon completion of this trial, we will have new knowledge about the effectiveness of diabetes decision aids in these practices. We will also better understand the factors that promote or inhibit the successful implementation and normalization of medication choice decision aids in the care of chronic patients in primary care practices
Molecular architecture of the Nup84–Nup145C–Sec13 edge element in the nuclear pore complex lattice
Nuclear pore complexes (NPCs) facilitate all nucleocytoplasmic transport. These massive protein assemblies are modular, with a stable structural scaffold supporting more dynamically attached components. The scaffold is made from multiple copies of the heptameric Y complex and the heteromeric Nic96 complex. We previously showed that members of these core subcomplexes specifically share an ACE1 fold with Sec31 of the COPII vesicle coat, and we proposed a lattice model for the NPC based on this commonality. Here we present the crystal structure of the heterotrimeric 134-kDa complex of Nup84–Nup145C–Sec13 of the Y complex. The heterotypic ACE1 interaction of Nup84 and Nup145C is analogous to the homotypic ACE1 interaction of Sec31 that forms COPII lattice edge elements and is inconsistent with the alternative 'fence-like' NPC model. We construct a molecular model of the Y complex and compare the architectural principles of COPII and NPC lattices.National Institutes of Health (U.S.) (Grant GM77537)Pew Charitable Trusts (Scholar Award
Apoptosis of Purified CD4+ T Cell Subsets Is Dominated by Cytokine Deprivation and Absence of Other Cells in New Onset Diabetic NOD Mice
BACKGROUND: Regulatory T cells (Treg) play a significant role in immune homeostasis and self-tolerance. Excessive sensitivity of isolated Treg to apoptosis has been demonstrated in NOD mice and humans suffering of type 1 diabetes, suggesting a possible role in the immune dysfunction that underlies autoimmune insulitis. In this study the sensitivity to apoptosis was measured in T cells from new onset diabetic NOD females, comparing purified subsets to mixed cultures. PRINCIPAL FINDINGS: Apoptotic cells are short lived in vivo and death occurs primarily during isolation, manipulation and culture. Excessive susceptibility of CD25(+) T cells to spontaneous apoptosis is characteristic of isolated subsets, however disappears when death is measured in mixed splenocyte cultures. In variance, CD25(-) T cells display balanced sensitivity to apoptosis under both conditions. The isolation procedure removes soluble factors, IL-2 playing a significant role in sustaining Treg viability. In addition, pro- and anti-apoptotic signals are transduced by cell-to-cell interactions: CD3 and CD28 protect CD25(+) T cells from apoptosis, and in parallel sensitize naïve effector cells to apoptosis. Treg viability is modulated both by other T cells and other subsets within mixed splenocyte cultures. Variations in sensitivity to apoptosis are often hindered by fast proliferation of viable cells, therefore cycling rates are mandatory to adequate interpretation of cell death assays. CONCLUSIONS: The sensitivity of purified Treg to apoptosis is dominated by cytokine deprivation and absence of cell-to-cell interactions, and deviate significantly from measurements in mixed populations. Balanced sensitivity of naïve/effector and regulatory T cells to apoptosis in NOD mice argues against the concept that differential susceptibility affects disease evolution and progression
Substantial variation across geographic regions in the obesity prevalence among 6–8 years old Hungarian children (COSI Hungary 2016)
Abstract Background There have been previous representative nutritional status surveys conducted in Hungary, but this is the first one that examines overweight and obesity prevalence according to the level of urbanization and in different geographic regions among 6–8-year-old children. We also assessed whether these variations were different by sex. Methods This survey was part of the fourth data collection round of World Health Organization (WHO) Childhood Obesity Surveillance Initiative which took place during the academic year 2016/2017. The representative sample was determined by two-stage cluster sampling. A total of 5332 children (48.4% boys; age 7.54 ± 0.64 years) were measured from all seven geographic regions including urban (at least 500 inhabitants per square kilometer; n = 1598), semi-urban (100 to 500 inhabitants per square kilometer; n = 1932) and rural (less than 100 inhabitants per square kilometer; n = 1802) areas. Results Using the WHO reference, prevalence of overweight and obesity within the whole sample were 14.2, and 12.7%, respectively. According to the International Obesity Task Force (IOTF) reference, rates were 12.6 and 8.6%. Northern Hungary and Southern Transdanubia were the regions with the highest obesity prevalence of 11.0 and 12.0%, while Central Hungary was the one with the lowest obesity rate (6.1%). The prevalence of overweight and obesity tended to be higher in rural areas (13.0 and 9.8%) than in urban areas (11.9 and 7.0%). Concerning differences in sex, girls had higher obesity risk in rural areas (OR = 2.0) but boys did not. Odds ratios were 2.0–3.4 in different regions for obesity compared to Central Hungary, but only among boys. Conclusions Overweight and obesity are emerging problems in Hungary. Remarkable differences were observed in the prevalence of obesity by geographic regions. These variations can only be partly explained by geographic characteristics. Trial registration Study protocol was approved by the Scientific and Research Ethics Committee of the Medical Research Council (61158–2/2016/EKU)
Activity and expression of progesterone metabolizing 5α-reductase, 20α-hydroxysteroid oxidoreductase and 3α(β)-hydroxysteroid oxidoreductases in tumorigenic (MCF-7, MDA-MB-231, T-47D) and nontumorigenic (MCF-10A) human breast cancer cells
BACKGROUND: Recent observations indicate that human tumorous breast tissue metabolizes progesterone differently than nontumorous breast tissue. Specifically, 5α-reduced metabolites (5α-pregnanes, shown to stimulate cell proliferation and detachment) are produced at a significantly higher rate in tumorous tissue, indicating increased 5α-reductase (5αR) activity. Conversely, the activities of 3α-hydroxysteroid oxidoreductase (3α-HSO) and 20α-HSO enzymes appeared to be higher in normal tissues. The elevated conversion to 5α-pregnanes occurred regardless of estrogen (ER) or progesterone (PR) receptor levels. To gain insight into these differences, the activities and expression of these progesterone converting enzymes were investigated in a nontumorigenic cell line, MCF-10A (ER- and PR-negative), and the three tumorigenic cell lines, MDA-MB-231 (ER- and PR-negative), MCF-7 and T-47D (ER- and PR-positive). METHODS: For the enzyme activity studies, either whole cells were incubated with [(14)C]progesterone for 2, 4, 8, and 24 hours, or the microsomal/cytosolic fraction was incubated for 15–60 minutes with [(3)H]progesterone, and the metabolites were identified and quantified. Semi-quantitative RT-PCR was employed to determine the relative levels of expression of 5αR type1 (SRD5A1), 5αR type 2 (SRD5A2), 20α-HSO (AKR1C1), 3α-HSO type 2 (AKR1C3), 3α-HSO type 3 (AKR1C2) and 3β-HSO (HSD3B1/HSD3B2) in the four cell lines using 18S rRNA as an internal control. RESULTS: The relative 5α-reductase activity, when considered as a ratio of 5α-pregnanes/4-pregnenes, was 4.21 (± 0.49) for MCF-7 cells, 6.24 (± 1.14) for MDA-MB-231 cells, 4.62 (± 0.43) for T-47D cells and 0.65 (± 0.07) for MCF-10A cells, constituting approximately 6.5-fold, 9.6-fold and 7.1 fold higher conversion to 5α-pregnanes in the tumorigenic cells, respectively, than in the nontumorigenic MCF-10A cells. Conversely, the 20α-HSO and 3α-HSO activities were significantly higher (p < 0.001) in MCF-10A cells than in the other three cell types. In the MCF-10A cells, 20α-HSO activity was 8-14-fold higher and the 3α-HSO activity was 2.5-5.4-fold higher than in the other three cell types. The values of 5αR:20α-HSO ratios were 16.9 – 32.6-fold greater and the 5αR:3α-HSO ratios were 5.2 – 10.5-fold greater in MCF-7, MDA-MB-231 and T-47D cells than in MCF-10A cells. RT-PCR showed significantly higher expression of 5αR1 (p < 0.001), and lower expression of 20α-HSO (p < 0.001), 3α-HSO2 (p < 0.001), 3α-HSO3 (p < 0.001) in MCF-7, MDA-MB-231 and T-47D cells than in MCF-10A cells. CONCLUSION: The findings provide the first evidence that the 5αR activity (leading to the conversion of progesterone to the cancer promoting 5α-pregnanes) is significantly higher in the tumorigenic MCF-7, MDA-MB-231 and T-47D breast cell lines than in the nontumorigenic MCF-10A cell line. The higher 5αR activity coincides with significantly greater expression of 5αR1. On the other hand, the activities of 20α-HSO and 3α-HSO are higher in the MCF-10A cells than in MCF-7, MDA-MB-231 and T-47D cells; these differences in activity correlate with significantly higher expression of 20α-HSO, 3α-HSO2 and 3α-HSO3 in MCF-10A cells. Changes in progesterone metabolizing enzyme expression (resulting in enzyme activity changes) may be responsible for stimulating breast cancer by increased production of tumor-promoting 5α-pregnanes and decreased production of anti-cancer 20α – and 3α-4-pregnenes
Combined loss of the BH3-only proteins Bim and Bmf restores B-cell development and function in TACI-Ig transgenic mice.
Terminal differentiation of B cells depends on two interconnected survival pathways, elicited by the B-cell receptor (BCR) and the BAFF receptor (BAFF-R), respectively. Loss of either signaling pathway arrests B-cell development. Although BCR-dependent survival depends mainly on the activation of the v-AKT murine thymoma viral oncogene homolog 1 (AKT)/PI3-kinase network, BAFF/BAFF-R-mediated survival engages non-canonical NF-κB signaling as well as MAPK/extracellular-signal regulated kinase and AKT/PI3-kinase modules to allow proper B-cell development. Plasma cell survival, however, is independent of BAFF-R and regulated by APRIL that signals NF-κB activation via alternative receptors, that is, transmembrane activator and CAML interactor (TACI) or B-cell maturation (BCMA). All these complex signaling events are believed to secure survival by increased expression of anti-apoptotic B-cell lymphoma 2 (Bcl2) family proteins in developing and mature B cells. Curiously, how lack of BAFF- or APRIL-mediated signaling triggers B-cell apoptosis remains largely unexplored. Here, we show that two pro-apoptotic members of the 'Bcl2 homology domain 3-only' subgroup of the Bcl2 family, Bcl2 interacting mediator of cell death (Bim) and Bcl2 modifying factor (Bmf), mediate apoptosis in the context of TACI-Ig overexpression that effectively neutralizes BAFF as well as APRIL. Surprisingly, although Bcl2 overexpression triggers B-cell hyperplasia exceeding the one observed in Bim(-/-)Bmf(-/-) mice, Bcl2 transgenic B cells remain susceptible to the effects of TACI-Ig expression in vivo, leading to ameliorated pathology in Vav-Bcl2 transgenic mice. Together, our findings shed new light on the molecular machinery restricting B-cell survival during development, normal homeostasis and under pathological conditions. Our data further suggest that Bcl2 antagonists might improve the potency of BAFF/APRIL-depletion strategies in B-cell-driven pathologies
Notch-induced T cell development requires phosphoinositide-dependent kinase 1
Phosphoinositide-dependent kinase l (PDK1) phosphorylates and activates multiple AGC serine kinases, including protein kinase B (PKB), p70Ribosomal S6 kinase (S6K) and p90Ribosomal S6 kinase (RSK). PDK1 is required for thymocyte differentiation and proliferation, and herein, we explore the molecular basis for these essential functions of PDK1 in T lymphocyte development. A key finding is that PDK1 is required for the expression of key nutrient receptors in T cell progenitors: CD71 the transferrin receptor and CD98 a subunit of L-amino acid transporters. PDK1 is also essential for Notch-mediated trophic and proliferative responses in thymocytes. A PDK1 mutant PDK1 L155E, which supports activation of PKB but no other AGC kinases, can restore CD71 and CD98 expression in pre-T cells and restore thymocyte differentiation. However, PDK1 L155E is insufficient for thymocyte proliferation. The role of PDK1 in thymus development thus extends beyond its ability to regulate PKB. In addition, PDK1 phosphorylation of AGC kinases such as S6K and RSK is also necessary for thymocyte development
Recommended from our members
Missed, not missing: Phylogenomic evidence for the existence of Avian FoxP3
The Forkhead box transcription factor FoxP3 is pivotal to the development and function of regulatory T cells (Tregs), which make a major contribution to peripheral tolerance. FoxP3 is believed to perform a regulatory role in all the vertebrate species in which it has been detected. The prevailing view is that FoxP3 is absent in birds and that avian Tregs rely on alternative developmental and suppressive pathways. Prompted by the automated annotation of foxp3 in the ground tit (Parus humilis) genome, we have questioned this assumption. Our analysis of all available avian genomes has revealed that the foxp3 locus is missing, incomplete or of poor quality in the relevant genomic assemblies for nearly all avian species. Nevertheless, in two species, the peregrine falcon (Falco peregrinus) and the saker falcon (F. cherrug), there is compelling evidence for the existence of exons showing synteny with foxp3 in the ground tit. A broader phylogenomic analysis has shown that FoxP3 sequences from these three species are similar to crocodilian sequences, the closest living relatives of birds. In both birds and crocodilians, we have also identified a highly proline-enriched region at the N terminus of FoxP3, a region previously identified only in mammals
- …