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71.
Direct estimation of biofilm density on different pipe material coupons using a specific DNA-probe 总被引:3,自引:0,他引:3
Chang YC Le Puil M Biggerstaff J Randall AA Schulte A Taylor JS 《Molecular and cellular probes》2003,17(5):237-243
A variety of approaches to quantify biomass in biofilms without disruption due to detachment have been developed over the years. One basic approach is the combination of advanced microscopy with molecular staining. However, many stains (e.g. 4',6-diamino-2-phenylindole, acridine orange or live-dead stains) can be non-specific when corrosion products, precipitates, and pipe material are present. In addition, some pipe materials cause high background when using epifluorescent microscopy. The new refinement discussed in this presentation used fluorescence spectroscopy to obtain the spectra from four common distribution system pipe materials: PVC, 'concrete' lined cast iron, cast iron, and galvanized steel. The emission maximum for all four materials was between 500 and 550 nm, but emissions radically decreased around 575-600 nm. A molecular probe, BO-PRO-3 (Molecular Probes, Inc., Eugene, OR, USA) was identified which has an emission intensity maximum at 599 nm (red), with emission intensity 200 times greater when it is bound to DNA. The BO-PRO-3 has greatly reduced non-specific staining and background problems. In the preliminary experiment, using diluted waste water, a significant exponential relationship was found between stained surface area/total area ratio and fixed biofilm inventory measurements from scraping heterotrophic plate counts (SHPC) on R2A medium. In addition, the biofilm inventory on different pipe material coupons from pilot distribution systems was also correlated to the stained surface area fraction and SHPC. 相似文献
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Tobias L. Schulte Florian Ringel Markus Quante Sven O. Eicker Cathleen Muche-Borowski Ralph Kothe 《European spine journal》2016,25(8):2359-2367
Surgery for isthmic and degenerative spondylolisthesis (SL) in adults is carried out very frequently in everyday practice. However, it is still unclear whether the results of surgery are better than those of conservative treatment and whether decompression alone or instrumented fusion with decompression should be recommended. In addition, the role of reduction is unclear. Four clinically relevant key questions were addressed in this study: (1) Is surgery more successful than conservative treatment in relation to pain and function in adult patients with isthmic SL? (2) Is surgery more successful than conservative treatment in relation to pain and function in adult patients with degenerative SL? (3) Is instrumented fusion with decompression more successful in relation to pain and function than decompression alone in adult patients with degenerative SL and spinal canal stenosis? (4) Is instrumented fusion with reduction more successful in relation to pain and function than instrumented fusion without reduction in adult patients with isthmic or degenerative SL? A systematic PubMed search was carried out to identify randomized and nonrandomized controlled trials on these topics. Papers were analyzed systematically in a search for the best evidence. A total of 18 studies was identified and analyzed: two for question 1, eight for question 2, four for question 3, and four for question 4. Surgery appears to be better than conservative treatment in adults with isthmic SL (poor evidence) and also in adults with degenerative SL (good evidence). Instrumented fusion with decompression appears to be more successful than decompression alone in adults with degenerative SL and spinal stenosis (poor evidence). Reduction and instrumented fusion does not appear to be more successful than instrumented fusion without reduction in adults with isthmic or degenerative SL (moderate evidence). 相似文献
74.
Abdominopelvic washings (APW) performed during gynecologic surgeries have become a common specimen evaluated by cytopathologists. Their role in staging of female genital tract tumors has changed significantly since they were first described, and continue to evolve. The ability of these washings to detect microscopic disease, even in the absence of gross disease, warrants the critical role that these washings play in the staging of certain female gynecologic tract tumors, allowing for optimal staging and subsequent treatment of the patient. Irrespective of the underlying pathology, the gamut of cytomorphologic findings that may be observed in APW is extensive, and ranges from benign lesions that may act as mimickers of malignancy, to both common and rare malignancies. This review discusses the changing role of APW in the staging of gynecologic tumors, and highlights the salient cytomorphologic features of these lesions, with emphasis in their correct identification, including cautionary notes to avoid over or misinterpretation. Diagn. Cytopathol. 2016;44:1039–1057. © 2016 Wiley Periodicals, Inc. 相似文献
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SJ Smith CV Rahman PA Clarke AA Ritchie TW Gould JH Ward KM Shakesheff RG Grundy R Rahman 《Annals of the Royal College of Surgeons of England》2014,96(7):495-501
Introduction
The median survival of patients with glioblastoma multiforme (astrocytoma grade 4) remains less than 18 months despite radical surgery, radiotherapy and systemic chemotherapy. Surgical implantation of chemotherapy eluting wafers into the resection cavity has been shown to improve length of survival but the current licensed therapy has several drawbacks. This paper investigates in vivo efficacy of a novel drug eluting paste in glioblastoma.Methods
Poly(lactic-co-glycolic acid)/poly(ethylene glycol) (PLGA/PEG) self-sintering paste was loaded with the chemotherapeutic agent etoposide and delivered surgically into partially resected tumours in a flank murine glioblastoma xenograft model.Results
Surgical delivery of the paste was successful and practical, with no toxicity or surgical morbidity to the animals. The paste was retained in the tumour cavity, and preliminary results suggest a useful antitumour and antiangiogenic effect, particularly at higher doses. Bioluminescent imaging was not affected significantly by the presence of the paste in the tumour.Conclusions
Chemotherapy loaded PLGA/PEG paste seems to be a promising technology capable of delivering active drugs into partially resected tumours. The preliminary results of this study suggest efficacy with no toxicity and will lead to larger scale efficacy studies in orthotopic glioblastoma models. 相似文献78.
Bernd Jergas Kirsten Schulte Laura Bindila Beat Lutz Eberhard Schlicker 《Naunyn-Schmiedeberg's archives of pharmacology》2014,387(7):621-628
The cannabinoid CB1 receptors on the noradrenergic neurons in guinea pig hippocampal slices show an endogenous endocannabinoid tone. This conclusion is based on rimonabant, the facilitatory effect of which on noradrenaline release might be due to its inverse CB1 receptor agonism and/or the interruption of a tonic inhibition elicited by endocannabinoids. To examine the latter mechanism, a neutral antagonist would be suitable. Therefore, we studied whether O-2050 is a neutral CB1 receptor antagonist in the guinea pig hippocampus and whether it mimics the facilitatory effect of rimonabant. CB1 receptor affinity of O-2050 was quantified in cerebrocortical membranes, using 3H-rimonabant binding. Its CB1 receptor potency and effect on 3H-noradrenaline release were determined in superfused hippocampal slices. Its intrinsic activity at CB1 receptors was studied in hippocampal membranes, using 35S-GTPγS binding. Endocannabinoid levels in hippocampus were determined by liquid chromatography-multiple reaction monitoring. O-2050 was about ten times less potent than rimonabant in its CB1 receptor affinity, potency and facilitatory effect on noradrenaline release. Although not affecting 35S-GTPγS binding by itself, O-2050 shifted the concentration-response curve of a CB1 receptor agonist to the right but that of rimonabant to the left. Levels of anandamide and 2-arachidonoyl glycerol in guinea pig hippocampus closely resembled those in mouse hippocampus. In conclusion, our results with O-2050 confirm that the CB1 receptors on noradrenergic neurons of the guinea pig hippocampus show an endogenous tone. To differentiate between the two mechanisms leading to an endogenous tone, O-2050 is not superior to rimonabant since O-2050 may increase the inverse agonistic effect of endocannabinoids. 相似文献
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B. C. Whitelaw J. K. Prague O. G. Mustafa K.‐M. Schulte P. A. Hopkins J. A. Gilbert A. M. McGregor S. J. B. Aylwin 《Clinical endocrinology》2014,80(1):13-22
Phaeochromocytoma crisis is an endocrine emergency associated with significant mortality. There is little published guidance on the management of phaeochromocytoma crisis. This clinical practice update summarizes the relevant published literature, including a detailed review of cases published in the past 5 years, and a proposed classification system. We review the recommended management of phaeochromocytoma crisis including the use of alpha‐blockade, which is strongly associated with survival of a crisis. Mechanical circulatory supportive therapy (including intra‐aortic balloon pump or extra‐corporeal membrane oxygenation) is strongly recommended for patients with sustained hypotension. Surgical intervention should be deferred until medical stabilization is achieved. 相似文献