Search results for "Models"
showing 10 items of 8211 documents
Determination of renal tissue ibandronate levels in rats with normal and mildly impaired renal function
2013
After entering the blood, bisphosphonates are immediately bound to bone or excreted unchanged by the kidney. During renal excretion about 0.5% of administrated dosage remains in kidney tissue. The renal tissue level of bisphosphonates (RTL) decreases over time and remains at about 0.15% after 3weeks, but the influence of renal insufficiency (RI) is unclear.We investigated the influence of mild to moderate RI on RTL of ibandronate (IBD). First a method for determination of RTL was implemented and validated. We measured RTL in rats with normal renal function (SHAM) and after unilateral nephrectomy (UNX). In each case one SHAM and one UNX groups received one or alternatively 9 times every 3wee…
A decade of trials of interferon-alpha for chronic hepatitis C. A meta-regression analysis
2003
The most relevant randomized controlled trials of interferon-alpha (IFN) for naive patients with chronic hepatitis C (CHC) published in a decade, just before appearance of pegylated IFN trials in 2000, were included in this paper. Its purpose is to review the relationship between sustained biochemical response in active versus control group versus usual clinical variables as IFN regimens, cirrhosis, genotype and versus less frequently addressed variables as funding, methodological quality or location of principal author. Meta-analysis estimates of global treatment effect varied according to trial design: group 1=IFN versus placebo/no treatment, 32 RCTs, 2499 pts, OR 9.5 (6.3-14.2); group 2a…
A score model for the continuous grading of early allograft dysfunction severity
2014
Early allograft dysfunction (EAD) dramatically influences graft and patient outcomes. A lack of consensus on an EAD definition hinders comparisons of liver transplant outcomes and management of recipients among and within centers. We sought to develop a model for the quantitative assessment of early allograft function [Model for Early Allograft Function Scoring (MEAF)] after transplantation. A retrospective study including 1026 consecutive liver transplants was performed for MEAF score development. Multivariate data analysis was used to select a small number of postoperative variables that adequately describe EAD. Then, the distribution of these variables was mathematically modeled to assig…
Liver specific deletion of CYLDexon7/8 induces severe biliary damage, fibrosis and increases hepatocarcinogenesis in mice
2012
Background & Aims CYLD is a tumor suppressor gene that is mutated in familial cylindromatosis, an autosomal dominant predisposition to tumors of skin appendages. Reduced CYLD expression has been observed in other tumor entities, including hepatocellular carcinoma. In the present study, we analyzed the role of CYLD in liver homeostasis and hepatocarcinogenesis in vivo . Methods Mice with liver-specific deletion of CYLDexon7/8 ( CYLD FF xAlbCre ) were generated. Liver tissues were histologically analyzed and oval cell activation was investigated. Hepatocarcinogenesis was induced by diethylnitrosamine/phenobarbital (DEN/PB). Microarray expression profiling of livers was performed in untreated …
Treatment of early childhood medulloblastoma by postoperative chemotherapy alone.
2005
The prognosis for young children with medulloblastoma is poor, and survivors are at high risk for cognitive deficits. We conducted a trial of the treatment of this brain tumor by intensive postoperative chemotherapy alone.After surgery, children received three cycles of intravenous chemotherapy (cyclophosphamide, vincristine, methotrexate, carboplatin, and etoposide) and intraventricular methotrexate. Treatment was terminated if a complete remission was achieved. Leukoencephalopathy and cognitive deficits were evaluated.Forty-three children were treated according to protocol. In children who had complete resection (17 patients), residual tumor (14), and macroscopic metastases (12), the five…
Signaling through BMPR-IA regulates quiescence and long-term activity of neural stem cells in the adult hippocampus.
2010
SummaryNeural stem cells (NSCs) in the adult hippocampus divide infrequently, and the molecules that modulate their quiescence are largely unknown. Here, we show that bone morphogenetic protein (BMP) signaling is active in hippocampal NSCs, downstream of BMPR-IA. BMPs reversibly diminish proliferation of cultured NSCs while maintaining their undifferentiated state. In vivo, acute blockade of BMP signaling in the hippocampus by intracerebral infusion of Noggin first recruits quiescent NSCs into the cycle and increases neurogenesis; subsequently, it leads to decreased stem cell division and depletion of precursors and newborn neurons. Consistently, selective ablation of Bmpr1a in hippocampal …
Tomographic left ventricular volume determination in the presence of aneurysm by three-dimensional echocardiographic imaging. I: Asymmetric model hea…
1996
To improve the accuracy of measurements of left ventricular volume in the presence of an aneurysm, we used three-dimensional echocardiographic imaging to analyze the shape of left ventricles in 23 asymmetric model hearts with eccentric aneurysms of different sizes, shapes, and localizations. A standard 3.75 MHz ultrasound probe with a rotation motor device was used to obtain a three-dimensional data set. By rotating the probe stepwise 1 degree, 180 radial ultrasound pictures were digitized. On the basis of the three-dimensional data set, the following parameters were determined and compared with the dimensions of the model hearts obtained by direct measurement: total left ventricular volume…
Haemoperfusion: a useful therapy for a severely poisoned patient?
1986
Although it is many years since a haemodialysis and haemoperfusion over uncoated and later coated charcoal columns have been used for the treatment of intoxicated patients, the clinical efficacy of these extracorporeal techniques in the treatment of severely poisoned patients remains a matter of debate. Some of the reasons for this controversy may be the indiscriminate use of haemoperfusion in any form of intoxication, the lack of well-controlled studies and the wrong interpretation of the high haemoperfusion clearance values sometimes obtained. Simple pharmacokinetic principles are applied to this type of treatment and some practical guidelines as to how and when haemoperfusion should be …
Precapillary Servo Control of Blood Pressure and Postcapillary Adjustment of Flow to Tissue Metabolic Status
1996
Background There are several shortcomings in current understanding of how the microvasculature maintains tissue homeostasis. Presently unresolved issues include (1) integration of the potentially conflicting needs for capillary perfusion and hydrostatic pressure regulation, (2) an understanding of signal transmission pathways for conveying information about tissue energetic status from undersupplied tissue sites to the arterioles, (3) accounting for the experimentally observed interrelations between precapillary and postcapillary resistances, and (4) an explanation of how precise local adjustment of perfusion to metabolic demands is achieved. Methods and Results A novel conceptualization o…
The Stretch-Shortening Cycle
2006
Neuromuscular fatigue has traditionally been examined using isolated forms of either isometric, concentric or eccentric actions. However, none of these actions are naturally occurring in human (or animal) ground locomotion. The basic muscle function is defined as the stretch-shortening cycle (SSC), where the preactivated muscle is first stretched (eccentric action) and then followed by the shortening (concentric) action. As the SSC taxes the skeletal muscles very strongly mechanically, its influence on the reflex activation becomes apparent and very different from the isolated forms of muscle actions mentioned above. The ground contact phases of running, jumping and hopping etc. are example…