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Atraumatic Pulsatile Leukocyte Circulation for Long‐Term In Vitro Dynamic Culture and Adhesion Assays 下载免费PDF全文
Low flow rate pumping of cell suspensions finds current applications in bioreactors for short‐term dynamic cell culture and adhesion assays. The aim of this study was to develop an atraumatic pump and hemodynamically adapted test circuit to allow operating periods of at least several hours. A computer‐controlled mini‐pump (MP) was constructed based on non‐occlusive local compression of an elastic tube with commercial bi‐leaflet valves directing the pulsatile flow into a compliant circuit. Cell damage and activation in the system were tested with whole blood in comparison with a set with a conventional peristaltic pump (PP). Activation of circulating THP‐1 monocytes was tested by measuring the expression of CD54 (ICAM‐1). Additionally, monocyte‐endothelial interactions were monitored using a parallel‐plate flow chamber with an artificial stenosis. The system required a priming volume of only 20 mL, delivering a peak pulsatile flow of up to 35 mL/min. After 8 h, blood hemolysis was significantly lower for MP with 11 ± 3 mg/dL compared with PP with 100 ± 16 mg/dL. CD142 (tissue factor) expression on blood monocytes was 50% lower for MP. With MP, THP‐1 cells could be pumped for extended periods (17 h), with no enhanced expression of CD54 permitting the long‐term co‐culture of THP‐1 with endothelial cells and the analysis of flow pattern effects on cell adhesion. A low‐damage assay setup was developed, which allows the pulsatile flow of THP‐1 cells and investigation of their interaction with other cells or surfaces for extended periods of time. 相似文献
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Anik Chevrier Ahou S. M. Kouao Genevieve Picard Mark B. Hurtig Michael D. Buschmann 《Journal of orthopaedic research》2015,33(1):63-70
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Vincenzo?Pavone Anna?MeleEmail author Daniela?Carlino Giorgina?Specchia Francesco?Gaudio Tommasina?Perrone Patrizio?Mazza Giulia?Palazzo Attilio?Guarini Giacomo?Loseto Prete?Eleonora Nicola?Cascavilla Potito?Scalzulli Angela?Melpignano Giovanni?Quintana Nicola?Di Renzo Giuseppe?Tarantini Silvana?Capalbo 《Annals of hematology》2018,97(10):1817-1824
Brentuximab vedotin (BV) shows a high overall response rate (ORR) in relapsed/refractory (R/R) Hodgkin lymphoma (HL) after autologous transplant (ASCT). The aim of this multicenter study, conducted in nine Hematology Departments of Rete Ematologica Pugliese, was to retrospectively evaluate the efficacy and safety of BV as salvage therapy and as bridge regimen to ASCT or allogeneic transplant (alloSCT) in R/R HL patients. Seventy patients received BV. Forty-five patients (64%) were treated with BV as bridge to transplant:16 (23%) patients as bridge to ASCT and 29 (41%) as bridge to alloSCT. Twenty-five patients (36%), not eligible for transplant, received BV as salvage treatment. The ORR was 59% (CR 26%). The ORR in transplant naïve patients was 75% (CR 31%). In patients treated with BV as bridge to alloSCT, the ORR was 62% (CR 24%). In a multivariate analysis, the ORR was lower in refractory patients (p?<?0.005). The 2y-OS was 70%. The median PFS was 17 months. Ten of the 16 (63%) naïve-transplant patients received ASCT, with 50% in CR before ASCT. In the 29 patients treated with BV as bridge to alloSCT, 28 (97%) proceeded to alloSCT with 25% in CR prior to alloSCT. The most common adverse events were peripheral neuropathy (50%), neutropenia (29%) and anemia (12%). These data suggest that BV is well tolerated and very effective in R/R HL, producing a substantial level of CR. BV may also be a key therapeutic agent to achieve good disease control before transplant, improving post- transplant outcomes, also in refractory and heavily pretreated patients, without significant overlapping toxicities with prior therapies. 相似文献
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Cyp7b, a novel brain cytochrome P450, catalyzes the synthesis of neurosteroids 7α-hydroxy dehydroepiandrosterone and 7α-hydroxy pregnenolone 下载免费PDF全文
Ken A. Rose Genevieve Stapleton Karin Dott Marie Paule Kieny Ruth Best Margrit Schwarz David W. Russell Ingemar Bjrkhem Jonathan Seckl Richard Lathe 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(10):4925-4930
Steroids produced locally in brain (neurosteroids), including dehydroepiandrosterone (DHEA), influence cognition and behavior. We previously described a novel cytochrome P450, Cyp7b, strongly expressed in rat and mouse brain, particularly in hippocampus. Cyp7b is most similar to steroidogenic P450s and potentially could play a role in neurosteroid metabolism. To examine the catalytic activity of the enzyme mouse Cyp7b cDNA was introduced into a vaccinia virus vector. Extracts from cells infected with the recombinant showed NADPH-dependent conversion of DHEA (Km, 13.6 μM) and pregnenolone (Km, 4.0 μM) to slower migrating forms on thin layer chromatography. The expressed enzyme was less active against 25-hydroxycholesterol, 17β-estradiol and 5α-androstane-3β,17β-diol, with low to undetectable activity against progesterone, corticosterone, and testosterone. On gas chromatography and mass spectrometry of the Cyp7b metabolite of DHEA the retention time and fragmentation patterns were identical to those obtained with authentic 7α-hydroxy DHEA. The reaction product also comigrated on thin layer chromatography with 7α-hydroxy DHEA but not with 7β-hydroxy DHEA; when [7α-3H]pregnenolone was incubated with Cyp7b extracts the extent of release of radioactivity into the medium suggested that hydroxylation was preferentially at the 7α position. Brain extracts also efficiently liberated tritium from [7α-3H]pregnenolone and converted DHEA to a product with a chromatographic mobility indistinguishable from 7α-hydroxy DHEA. We conclude that Cyp7b is a 7α-hydroxylase participating in the synthesis, in brain, of neurosteroids 7α-hydroxy DHEA, and 7α-hydroxy pregnenolone. 相似文献
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Nancy Cardinez Leif E. Lovblom Johnny-Wei Bai Evan Lewis Alon Abraham Daniel Scarr Julie A. Lovshin Yuliya Lytvyn Genevieve Boulet Mohammed A. Farooqi Andrej Orszag Alanna Weisman Hillary A. Keenan Michael H. Brent Narinder Paul Vera Bril David Z. Cherney Bruce A. Perkins 《Journal of diabetes and its complications》2018,32(7):660-664