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131.
Idiopathic pulmonary fibrosis is characterized by a progressive scarring and stiffening of the peripheral lung tissue that decreases lung function. Over the course of the disease, the lung microvasculature undergoes extensive remodeling. There is increased angiogenesis around fibrotic foci and an absence of microvessels within the foci. To elucidate how the anti-fibrotic drug nintedanib acts on vascular remodeling, we used an in vitro model of perfusable microvessels made with primary endothelial cells and primary lung fibroblasts in a microfluidic chip. The microvasculature model allowed us to study the impact of nintedanib on permeability, vascularized area, and cell–cell interactions. The anti-vasculogenic impact of nintedanib was visible at the minimal concentrations of 10 nM, showing a significant increase in vessel permeability. Furthermore, nintedanib decreased microvessel density, diameter, and influenced fibroblast organization around endothelial microvessels. These results show that nintedanib acts on the endothelial network formation and endothelial–perivascular interactions. Advanced in vitro microvasculature models may thus serve to pinpoint the mechanistic effect of anti-fibrotic drugs on the microvascular remodeling in 3D and refine findings from animal studies.  相似文献   
132.
Rapid screening of methicillin‐resistant Staphylococcus aureus (MRSA) colonization prior to hospital admittance is important to reduce nosocomial infections and health care costs. Molecular detection of mecA and S. aureus specific target genes has become widely established for this purpose. However, there are still limitations in potential for high‐throughput screening in the methods described. We have compared the time aspects and workload of four different DNA preparation platforms, resulting in an automated and simple MRSA screening method which combines two liquid handling systems and a simple lysis buffer. We have further transferred our in‐house dual real‐time PCR to a fast‐PCR protocol, reducing the time and labour spent on these samples to a minimum.  相似文献   
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Statement of problem

Polymeric material for 3-dimensional printing can be used to fabricate occlusal devices. However, information about fracture resistance and wear is scarce.

Purpose

The purpose of this in vitro study was to investigate the fracture resistance and 2-body wear of 3-dimensional–printed (3DP) (FotoDent splint; Dreve Dentamid GmbH), milled polymethylmethacrylate (CAM) (Temp Basic; Transpa 95H16, Zirkonzahn GmbH), and conventionally fabricated polymethylmethacrylate (CAST) (Castdon; Dreve Dentamid GmbH) occlusal devices.

Material and Methods

A total of 96 occlusal devices were prepared according to the 3 different manufacturing techniques 3DP, CAM, and CAST (n=32). For each manufacturing technique, specimens were further divided into initial fracture resistance tests (n=16) and artificial aging in the mastication simulator (50 N, 37°C) with 2-body wear followed by fracture resistance tests (n=16). The fracture resistance was determined using a universal testing machine (1 mm/min). The wear was measured after 20?000 and 120?000 mastication cycles with the replica technique, mapped with a laser scanner, and quantified in R software. Data were analyzed using a 2-way ANOVA followed by a 1-way ANOVA with Scheffé or Games-Howell post hoc tests, repeated measures ANOVA with corrected Greenhouse-Geisser P values, and the Levene, Mann-Whitney, and paired t tests (α=.05).

Results

CAM presented higher initial fracture resistance than 3DP or CAST (P<.001). After mastication simulation, CAM followed by 3DP showed higher fracture resistance than CAST (P<.001). Mastication simulation decreased the fracture resistance for CAM and CAST (P<.001) but not for 3DP (P=.78). Three-dimensional–printed occlusal devices showed the highest material volume loss, followed by CAM and the lowest in CAST (P<.001).

Conclusions

Three-dimensional–printed occlusal devices showed lower wear resistance and lower fracture resistance than those milled or conventionally fabricated. Therefore, only short-term application in the mouth is recommended. Further developments of occlusal device material for 3-dimensional printing are necessary.  相似文献   
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Cardiac involvement in systemic light chain amyloidosis (AL) is generally associated with a worse outcome, especially if other organs are also involved. We sought to determine whether concurrent cardiac and renal involvement were associated with a worse outcome than either organ alone. We identified 129 patients with AL, who received high‐dose chemotherapy followed by autologous hematopoietic stem cell transplantation (auto‐HCT) at our institution between 1997 and 2014. Ninety‐nine patients had either renal (group 1: n = 62, 62%), cardiac (group 2: n = 20, 20%), or both cardiac and renal (group 3: n = 17, 17%) involvement. The overall hematological response rate (CR+VGPR+PR) post‐auto‐HCT in groups 1, 2, and 3 was 69%, 74% and 82%, respectively (P = 0.62). Overall, organ response in groups 1, 2, and 3 was 39%, 42%, and 70%, respectively. The median PFS from auto‐HCT in groups 1, 2, and 3 was not reached (NR), 13.3 and 21 months, respectively (P = 0.02). The median OS in groups 1, 2, and 3 was 120, 46, and 60 months, respectively (P = 0.1). In conclusion, median PFS and OS in patients with concurrent cardiac and renal AL were comparable to patients with cardiac AL only, but worse than patients with renal AL.  相似文献   
138.
Background: Primary cutaneous CD30+ anaplastic large cell lymphomas (C‐ALCL) have indolent clinical behavior with an estimated 5‐year survival rate of 95%. The clinical features and disease courses of C‐ALCL identified in the lymphoma registry of Mannheim University hospital are described in the following. Patients and methods: All C‐ALCL patients identified in the database were analyzed in regard to clinical picture, histology, immunohistochemistry, molecular biology, staging, therapy, follow‐up, and outcome. Results: 14 C‐ALCL patients were identified. The mean age was 69 years and 57% were men. Solitary skin lesions in one anatomical region were seen in 12 patients upon initial diagnosis. Two patients presented with multiple lesions at different anatomical sites. In 2 patients there was specific lymph node involvement. In one C‐ALCL patient, follow‐up over 17 months revealed extracutaneous infiltration. Half of the patients relapsed and 36% had multiple episodes. The majority of our patients were treated with surgical excision followed by electron beam radiotherapy. The 5‐year survival rate was 93% in C‐ALCL. Conclusions: The clinical presentation of C‐ALCL varies. Staging procedures and a close clinical pathological correlation at initial diagnosis are essential. Due to a high rate of relapses and the possibility of developing extranodal manifestations over the course of the disease, close follow‐up is recommended.  相似文献   
139.
The reluctance of students in health professions to care for AIDS patients is partially based on the perceived risk of transmission of HIV from patient contact. We hypothesize that fear of contagion is due to lack of knowledge and deep‐rooted attitudes and emotions existing even in areas of low HIV seroprevalence. We tested this hypothesis on medical, nursing, and medical technology students. Using a questionnaire that yielded four scales, results showed only 58% of students were knowledgeable, 81% were fearful of contagion, 57% were homophobic, and 8% had death anxiety. Lack of knowledge was correlated with fear of contagion (p < .05), whereas homophobia was weakly associated (p = .08). We conclude that this perceived risk of infection is a result of lack of knowledge, disbelief of the facts, and the interplay of personal values and emotions. Alternative educational methods are needed to increase students’ knowledge and to encourage students to examine their personal feelings and attitudes.  相似文献   
140.
Prior findings in vitro of a TGF-β3 dependent mechanism induced by low dose-rate irradiation and resulting in increased radioresistance and removal of low dose hyper-radiosensitivity (HRS) was tested in an in vivo model. DBA/2 mice were given whole-body irradiation for 1 h at low dose-rates (LDR) of 0.3 or 0.03 Gy/h. Serum was harvested and added to RPMI (4% mouse serum and 6% bovine serum).This medium was transferred to reporter cells (T-47D breast cancer cells or T98G glioblastoma cells). The response to subsequent challenge irradiation of the reporter cells was measured by the colony assay. While serum from unirradiated control mice had no effect on the radiosensitivity in the reporter cells, serum from mice given 0.3 Gy/h or 0.03 Gy/h for 1 h removed HRS and also increased survival in response to doses up to 5 Gy. The effect lasted for at least 15 months after irradiation. TGF-β3 neutralizer added to the medium containing mouse serum inhibited the effect. Serum from mice given irradiation of 0.3 Gy/h for 1 h and subsequently treated with iNOS inhibitor 1400W did not affect radiosensitivity in reporter cells; neither did serum from the unirradiated progeny of mice given 1h LDR whole-body irradiation.  相似文献   
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