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61.
It has been shown previously that cryopreservation, using an ice‐free cryopreservation method with the cryoprotectant formulation VS83, beneficially modulated immune reactions in vivo and in vitro when compared with conventionally frozen tissues. In this study, we assessed the impact of a VS83 post‐treatment of previously conventionally frozen human tissue on responses of human immune cells in vitro. Tissue punches of treated and non‐treated (control) aortic heart valve tissue (leaflets and associated aortic root) were co‐cultured for 7 days with peripheral blood mononuclear cells or enriched CD14+ monocytes. Effects on cellular activation markers, cytokine secretion and immune cell proliferation were analysed by flow cytometry. Flow cytometry studies showed that VS83 treatment of aortic root tissue promoted activation and differentiation of CD14+ monocytes, inducing both up‐regulation of CD16 and down‐regulation of CD14. Significantly enhanced expression levels for the C‐C chemokine receptor (CCR)7 and the human leukocyte antigen (HLA)‐DR on monocytes co‐cultured with VS83‐treated aortic root tissue were measured, while the interleukin (IL)‐6 and monocyte chemoattractant protein (MCP)‐1 release was suppressed. However, the levels of interferon (IFN)γ and tumour necrosis factor (TNF)α remained undetectable, indicating that complete activation into pro‐inflammatory macrophages did not occur. Similar, but non‐significant, changes occurred with VS83‐treated leaflets. Additionally, in co‐cultures with T cells, proliferation and cytokine secretion responses were minimal. In conclusion, post‐treatment of conventionally cryopreserved human heart valve tissue with the VS83 formulation induces changes in the activation and differentiation characteristics of human monocytes, and thereby may influence long‐term performance following implantation. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
62.
Objective: To independently validate the predictive value of the intensive care requirement score (IRS) in unselected poisoned patients.

Design: Retrospective chart review.

Patients and methods: Five hundred and seventeen out of 585 admissions for acute intoxications could be analyzed. Eleven were excluded for a condition already requiring intensive care unit (ICU) support at admission (e.g., preclinical intubation). A further 57 admissions were excluded due to missing data. The IRS was calculated using a point-scoring system including age, Glasgow Coma Scale, heart rate, type of intoxication, and preexisting conditions. It was then compared to a composite endpoint indicating an ICU requirement (death in hospital, vasopressors, need for ventilation). The endpoint and the point-scoring system were identical to the original publication of the score.

Results and conclusion: Twenty-three out of 517 patients had a complicated clinical course as defined by meeting the endpoint definition. Twenty-one out of 23 complicated courses had a positive IRS (defined as greater or equal 6 points), as compared to 255/494 patients with an uncomplicated clinical course (p?相似文献   
63.

Aim

This study evaluated the influence of rivaroxaban 20 mg once daily on international normalized ratio (INR) during the co-administration period when switching from rivaroxaban to warfarin.

Methods

We developed a calibrated coagulation model that was qualified with phase I clinical data. Prothrombin time and INR values were simulated by use of phospholipid concentrations that matched Neoplastin Plus® and Innovin® reagents. To simulate the combined effects of rivaroxaban and warfarin on INR during switching, warfarin initiation was simulated by adjusting the magnitude of the warfarin effect to reach the desired target INRs over the course of 21 days. The warfarin effect values (obtained every 6 h) and the desired rivaroxaban plasma concentrations were used. Nomograms were generated from rivaroxaban induced increases in INR.

Results

The simulation had good prediction quality. Rivaroxaban induced increases in the total INR from the warfarin attributed INR were seen, which increased with rivaroxaban plasma concentration. When the warfarin only INR was 2.0–3.0, the INR contribution of rivaroxaban with Neoplastin Plus® was 0.5–1.2, decreasing to 0.3–0.6 with Innovin® at median trough rivaroxaban plasma concentrations (38 μg l−1).

Conclusions

The data indicate that measuring warfarin induced changes in INR are best performed at trough rivaroxaban concentrations (24 h after rivaroxaban dosing) during the co-administration period when switching from rivaroxaban to warfarin. Furthermore, Innovin® is preferable to Neoplastin Plus® because of its substantially lower sensitivity to rivaroxaban, thereby reducing the influence of rivaroxaban on the measured INR.  相似文献   
64.
Cocaine users consistently develop working memory (WM) impairments but the mediating molecular mechanisms are unknown so far. Recent evidence suggests that the serotonin (5-HT) system is altered by chronic cocaine use, while also being involved in WM processing. Thus, we investigated the effects of genetic variations impacting 5-HT activity and of peripheral 5-HT transporter (5-HTT) mRNA expression on WM performance in cocaine users and stimulant naive controls. Two hundred twenty participants (126 cocaine users, 94 controls) were assessed with visuospatial, spatial, and verbal WM tasks, genotyped for the length polymorphism in the promoter region of the 5-HTT (5-HTTLPR), the variable number of tandem repeats in the second intron of the 5-HTT (VNTR In2), two single-nucleotide polymorphisms (rs4570625 and rs1386497) in the tryptophan hydroxylase-2 (TPH2) gene and quantified for peripheral 5-HTT mRNA expression in whole-blood samples. Several significant gene × environment interactions between 5-HT genotypes and cocaine use on WM emerged: in cocaine users, the long/long (5-HTTLPR), 9+10/9+10 (VNTR In2) and C/C (TPH2 rs1386497) genotypes were risk alleles for WM impairments, whereas in healthy controls these polymorphisms were associated with improved WM performance. Analogously, high 5-HTT mRNA levels were associated with worse executive WM performance in cocaine users but with increased performance in controls. These gene × environment interactions suggest that the 5-HT system has an important role in the development of cognitive deficits in chronic cocaine users. Hence, pharmacological compounds targeting 5-HT neurotransmission might be promising for the treatment of cognitive deficits in cocaine dependence.  相似文献   
65.
Trait anxiety is a risk factor for the development and maintenance of affective disorders, and insights into the underlying brain mechanisms are vital for improving treatment and prevention strategies. Translational studies in non-human primates, where targeted neurochemical and genetic manipulations can be made, are critical in view of their close neuroanatomical similarity to humans in brain regions implicated in trait anxiety. Thus, we characterised the serotonergic and regional brain volume correlates of trait-like anxiety in the marmoset monkey. Low- and high-anxious animals were identified by behavioral responses to a human intruder (HI) that are known to be sensitive to anxiolytic drug treatment. Extracellular serotonin levels within the amygdala were measured with in vivo microdialysis, at baseline and in response to challenge with the selective serotonin reuptake inhibitor, citalopram. Regional brain volume was assessed by structural magnetic resonance imaging. Anxious individuals showed persistent, long-term fearful responses to both a HI and a model snake, alongside sustained attention (vigilance) to novel cues in a context associated with unpredictable threat. Neurally, high-anxious marmosets showed reduced amygdala serotonin levels, and smaller volumes in a closely connected prefrontal region, the dorsal anterior cingulate cortex. These findings highlight behavioral and neural similarities between trait-like anxiety in marmosets and humans, and set the stage for further investigation of the processes contributing to vulnerability and resilience to affective disorders.  相似文献   
66.
Against the background of increasing numbers of resistant microorganisms, the fast and cost-efficient detection of microbial resistance is an important clinical requirement for optimal therapeutic intervention. Current routine assays take at least 5 h, but in most cases an overnight incubation is necessary to identify resistant isolates. The usage of matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) profiling in combination with growth media containing isotopically labeled amino acids facilitates the detection of resistant microorganisms after 3 h or less directly from the profile spectrum. Growing microorganisms incorporate isotopically labeled amino acids, increasing protein masses and thereby leading to mass shifts of their corresponding peaks in the profile spectra. In the presence of antibiotics, only resistant microorganisms are able to grow and to incorporate the labeled amino acids. This leads to a difference in the mass spectra of susceptible and resistant isolates, allowing their differentiation. In the presented study, we demonstrated the applicability of this novel approach for the detection of methicillin-resistant Staphylococcus aureus and tested different bioinformatics approaches for automated data interpretation.  相似文献   
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Der Freie Zahnarzt -  相似文献   
70.
ObjectivesThis study aimed at 1) adapting the well-established Speech Handicap Index (SHI) to German, 2) testing the suitability of the instrument for assessing speech-related quality of life, 3) comparing it to the German Voice-Handicap-Index (VHI), in order to support treatment of oral cancer patients who experience posttreatment speech difficulties that affect their quality of life.Material and methodsParticipants completed a web-based survey that employed a 2 (experienced problem: speech/articulation-related vs. voice-related) x 2 (SHI vs. VHI) between-subject experimental design, enabling it to distinguish between the experiences of voice and intelligibility impairments, and to determine the discriminatory ability of the two instruments.ResultsThe German SHI reliably assessed speech intelligibility and articulation-related Quality of life. While voice impairments were equally well assessed by both, VHI: M 2.48, SD 0.65; SHI: M 2.52, SD 0.63; only the latter appropriately registered intelligibility handicap in speech impairments (VHI: M 2.05, SD 0.70; SHI: 2.68, SD 0.73). The responsivity of the SHI in capturing the experienced handicap was significantly greater in the speech/articulation-impairment condition (p = .001).ConclusionThe German SHI is a reliable and responsive measure for speech intelligibility and articulation-related quality of life that should be chosen in preference to the VHI.  相似文献   
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