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101.
Wolfgang G. Kreyling Uwe Holzwarth Nadine Haberl Ján Kozempel Alexander Wenk Stephanie Hirn 《Nanotoxicology》2017,11(4):454-464
The biokinetics of a size-selected fraction (70?nm median size) of commercially available and 48V-radiolabeled [48V]TiO2 nanoparticles has been investigated in healthy adult female Wistar-Kyoto rats at retention time-points of 1?h, 4?h, 24?h, 7?d and 28?d after intratracheal instillation of a single dose of an aqueous [48V]TiO2-nanoparticle suspension. A completely balanced quantitative biodistribution in all organs and tissues was obtained by applying typical [48V]TiO2-nanoparticle doses in the range of 40–240?μg·kg?1 bodyweight and making use of the high sensitivity of the radiotracer technique. The [48V]TiO2-nanoparticle content was corrected for residual blood retained in organs and tissues after exsanguination and for 48V-ions not bound to TiO2-nanoparticles. About 4% of the initial peripheral lung dose passed through the air-blood-barrier after 1?h and were retained mainly in the carcass (4%); 0.3% after 28?d. Highest organ fractions of [48V]TiO2-nanoparticles present in liver and kidneys remained constant (0.03%). [48V]TiO2-nanoparticles which entered across the gut epithelium following fast and long-term clearance from the lungs via larynx increased from 5 to 20% of all translocated/absorbed [48V]TiO2-nanoparticles. This contribution may account for 1/5 of the nanoparticle retention in some organs. After normalizing the fractions of retained [48V]TiO2-nanoparticles to the fraction that reached systemic circulation, the biodistribution was compared with the biodistributions determined after IV-injection (Part 1) and gavage (GAV) (Part 2). The biokinetics patterns after IT-instillation and GAV were similar but both were distinctly different from the pattern after intravenous injection disproving the latter to be a suitable surrogate of the former applications. Considering that chronic occupational inhalation of relatively biopersistent TiO2-particles (including nanoparticles) and accumulation in secondary organs may pose long-term health risks, this issue should be scrutinized more comprehensively. 相似文献
102.
Otte Marie-Luise Schmitgen Mike M. Kubera Katharina M. Wolf Nadine D. Fritze Stefan Geiger Lena S. Tost Heike Seidl Ulrich W. Meyer-Lindenberg Andreas Hirjak Dusan Wolf Robert C. 《European archives of psychiatry and clinical neuroscience》2022,272(6):985-995
European Archives of Psychiatry and Clinical Neuroscience - Insight into illness in schizophrenia (SZ) patients has a major impact on treatment adherence and outcome. Previous studies have linked... 相似文献
103.
Caroline Jouan Violaine Emonard Philippe Ruggeri Laurent Debelle Nadine Hincourt Sophie Lorquet 《Gynecological endocrinology》2016,32(10):807-810
The optimal method to prepare endometrium before frozen embryo transfer (FET) is not yet established. We retrospectively studied 4496 FET and detailed pregnancy and miscarriage rates in three groups of patients according to the endometrium preparation they have followed before their successive FET: clomifene citrate (CC, group 1), artificial cycle (AC, group 2) or switch between CC and AC (group 3). The overall pregnancy rates per transfer were 24.3, 20.8 and 17.3% while the miscarriage rates reached 23.2, 29.8 and 42.5%, respectively. Group 1 experienced the highest ongoing pregnancy rate (18.6%), the lowest being observed in group 3 (10.0%, p?0.001). Here we propose several alternatives to improve our AC protocol (group 2) that seemed less effective than CC (group 1) and we consider the use of a gonadotrophin-stimulated treatment for patients with the lowest reproductive outcomes (group 3). 相似文献
104.
Audrey Auclair Julie Martin Marjorie Bastien Nadine Bonneville Laurent Biertho Simon Marceau Frédéric-Simon Hould Simon Biron Stéfane Lebel Odette Lescelleur Jean-Pierre Després Paul Poirier 《Obesity surgery》2016,26(8):1717-1727
Background
Severe obesity is often characterized by ectopic fat deposition, which is related to development of type 2 diabetes (T2D). Thus, resolution of T2D may not be linearly associated with weight loss. The importance of ectopic fat reduction after bariatric surgery and T2D resolution is uncertain.Objective
The aim of this pilot study is to compare body composition and body fat distribution in severely obese patients with or without T2D after biliopancreatic diversion with duodenal switch (BPD-DS) surgery in relation to diabetes resolution.Methods
Sixty-two severely obese patients were evaluated at baseline, 6, and 12 months. Of these, 40 patients underwent BPD-DS surgery. Anthropometric measurements and abdominal and mid-thigh computed tomography scans were performed at each visit.Results
Before BPD-DS surgery, obese patients with T2D had higher weight as well as greater ectopic fat deposition in the abdomen and mid-thigh level than obese patients without T2D (p?<?0.05). Resolution of T2D was 65 and 90 % at 6 and 12 months, respectively. No difference in body composition changes at 6 and 12 months could be found between patients without T2D, patients with T2D resolution, and patients who remained T2D. Resolution of T2D was associated with a greater absolute loss of visceral adipose tissue (VAT) in comparison to patients without T2D (?1175?±?570 cm3 vs. ?729?±?394 cm3 at 6 months and ?1647?±?816 cm3 vs. ?1103?±?422 cm3 at 12 months; all p?≤?0.05).Conclusion
Ectopic fat mobilization, particularly the absolute loss of VAT, may play a major role in T2D resolution following BPD-DS surgery, regardless of the amount of weight loss.105.
Enhancing spiritual well-being among suicidal African American female survivors of intimate partner violence 总被引:1,自引:0,他引:1
Arnette NC Mascaro N Santana MC Davis S Kaslow NJ 《Journal of clinical psychology》2007,63(10):909-924
Spirituality has been identified as one component of a culturally competent therapeutic intervention for African American women. The present study was designed to investigate the ability of factors, such as level of hopelessness and the use of positive religious coping strategies, to predict spiritual well-being over time. Seventy-four low-income African American women were administered self-report questionnaires measuring hopelessness, use of religious coping strategies, and two domains of spiritual well-being. Path analysis indicated that hopelessness, existential well-being, religious well-being, and positive religious coping are correlated with one another. Further, lower levels of hopelessness predict increases in existential well-being over time; higher levels of positive religious coping predict increases in religious well-being over time. Results were consistent with the study hypotheses and highlight the need to attend to predictors of spiritual well-being when implementing culturally relevant interventions with abused, suicidal African American women. Therapeutic strategies for reducing hopelessness and enhancing positive religious coping to improve spiritual and existential well-being are presented; such strategies will ensure the interventions are more culturally competent. 相似文献
106.
Nitrate sensing and metabolism modulate motility, biofilm formation, and virulence in Pseudomonas aeruginosa 下载免费PDF全文
Infection by the bacterial opportunist Pseudomonas aeruginosa frequently assumes the form of a biofilm, requiring motility for biofilm formation and dispersal and an ability to grow in nutrient- and oxygen-limited environments. Anaerobic growth by P. aeruginosa is accomplished through the denitrification enzyme pathway that catalyzes the sequential reduction of nitrate to nitrogen gas. Mutants mutated in the two-component nitrate sensor-response regulator and in membrane nitrate reductase displayed altered motility and biofilm formation compared to wild-type P. aeruginosa PAO1. Analysis of additional nitrate dissimilation mutants demonstrated a second level of regulation in P. aeruginosa motility that is independent of nitrate sensor-response regulator function and is associated with nitric oxide production. Because motility and biofilm formation are important for P. aeruginosa pathogenicity, we examined the virulence of selected regulatory and structural gene mutants in the surrogate model host Caenorhabditis elegans. Interestingly, the membrane nitrate reductase mutant was avirulent in C. elegans, while nitrate sensor-response regulator mutants were fully virulent. The data demonstrate that nitrate sensing, response regulation, and metabolism are linked directly to factors important in P. aeruginosa pathogenesis. 相似文献
107.
Here we report for the first time that MCS-18, a novel natural product isolated from Helleborus purpurascens, is able to inhibit the expression of typical molecules of mature dendritic cells (DC) such as CD80, CD86, and especially of CD83 subsequently leading to a clear and dose-dependent inhibition of the DC-mediated T-cell stimulation. Furthermore, MCS-18 impeded the formation of the typical DC/T-cell clusters, which are essential to induce potent immune responses. Interestingly, MCS-18 also inhibited CCR7 expression on DC which subsequently lead to a dose-dependent block of the CCL19-mediated DC migration. MCS-18 not only inhibited the DC-mediated T-cell stimulation but also the anti-CD3/anti-CD28-mediated T-cell stimulation. Strikingly, MCS-18 also strongly reduced the paralysis associated with the experimental autoimmune encephalomyelitis (EAE), which is a murine model for human multiple sclerosis, in a prophylactic as well as in a "real" therapeutic setting. Even when the EAE was induced for a second time, the MCS-18-treated animals were still protected, suggesting that MCS-18 induces a long-lasting suppressive effect. In addition, and very important for the potential practical application in humans, MCS-18 was also active when administered orally. MCS-18 treatment almost completely reduced leukocyte infiltration in the brain and in the spinal cord. In conclusion, using in vitro as well in vivo assays we were able to show that MCS-18 exerts a strong immunosuppressive activity with remarkable potential for the therapy of diseases characterized by a pathologically over-activated immune system. 相似文献
108.
Schönherr N Meyer E Roos A Schmidt A Wollmann HA Eggermann T 《Journal of medical genetics》2007,44(1):59-63
Silver-Russell syndrome (SRS) is a heterogeneous disorder characterised by severe intrauterine and postnatal growth retardation, limb and body asymmetry, a typical facial appearance and less common dysmorphisms. Recently, epimutations and maternal duplications affecting the short arm of chromosome 11 have been shown to have a crucial role in the aetiology of the disease. Disturbances in the same genomic region cause the overgrowth disorder Beckwith-Wiedemann syndrome (BWS). In BWS, mutations in the telomeric as well as in the centromeric imprinting centres (ICR1 and ICR2) in 11p15 can be observed. In SRS, methylation defects in the imprinted region in 11p15 were considered to be restricted to the telomeric ICR1. They can be detected in about 30% of patients. This article reports on the first patient with SRS with a cryptic duplication restricted to the centromeric ICR2 domain in 11p15. The maternally inherited duplication in this patient included a region of 0.76-1 Mbp and affected the genes regulated by the ICR2, among them CDKN1C and LIT1. This study provides evidence for a role for this imprinting centre in the aetiology of SRS and shows that SRS presents a picture genetically opposite to that of BWS. 相似文献
109.
110.
Wentzell Nadine Haug Ulrike Schink Tania Engel Susanne Liebentraut Judith Linder Roland Onken Marlies Schaefer Christof Dathe Katarina 《Bundesgesundheitsblatt, Gesundheitsforschung, Gesundheitsschutz》2018,61(8):1022-1029
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Aufgrund des teratogenen Potenzials von Valproat wurden die Empfehlungen zur Risikoaufklärung und Verordnung bei... 相似文献