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101.
DAA‐based antiviral treatment of patients with chronic hepatitis C in the pre‐ and postkidney transplantation setting 下载免费PDF全文
Sandra Beinhardt Ramona Al Zoairy Peter Ferenci Karin Kozbial Clarissa Freissmuth Rafael Stern Albert Friedrich Stättermayer Rudolf Stauber Michael Strasser Heinz Zoller Bruno Watschinger Alice Schmidt Michael Trauner Harald Hofer Andreas Maieron 《Transplant international》2016,29(9):999-1007
DAA‐based regimens for chronic hepatitis C infection encourage treatment of “difficult‐to‐treat” cohorts. This study investigated efficacy and safety of DAA‐based regimens in HCV patients on dialysis or postkidney or liver/kidney transplantation. Twenty‐five patients treated with DAA combinations were evaluated: 10 were on dialysis (eight: hemodialysis, two: peritoneal dialysis), eight were kidney transplant recipients, and seven were liver/kidney transplant recipients. Except for one patient treated with daclatasvir ([DCV]/60 mg/QD)/simeprevir ([SMV]/150 mg/QD), the others received sofosbuvir‐based regimens ([SOF];400 mg/QD) combined with SMV:eight, DCV:13 or either ledipasvir ([LDV]90 mg/QD), ribavirin ([RBV];weight based) or pegylated interferon/RBV. HCV‐RNA was determined by Abbott RealTime (LLOQ]:12 IU/ml) or Roche AmpliPrep/COBAS TaqMan assay (LLOQ:15 IU/ml); treatment response evaluated every 4 weeks, at the end of treatment, and 4 and 12 weeks thereafter. Twenty‐four (96%) patients achieved SVR 12/24 (ITT‐analysis). Mean treatment duration was 15.1 ± 5.1 weeks (±SD), and two patients terminated prematurely – both reached SVR12. Six patients were hospitalized due to complications of underlying disease. One patient achieved SVR24 but was re‐infected (week 27). Kidney function remained stable; serum creatinine increased in only one patient – SOF was reduced to 400 mg/48 h. Treatment with DAA combinations in renally impaired HCV patients is highly effective and well tolerated. These findings call for further controlled trials and data from real‐life cohorts. 相似文献
102.
Osteonecrosis of jaw in patient with hormone-refractory prostate cancer treated with zoledronic acid
Intravenous bisphosphonates are widely used in the management of metastatic bone disease, as well as osteoporosis. Recent published reports have documented a possible link between treatment with intravenous bisphosphonates and osteonecrosis of the jaw. We report a case of osteonecrosis of the jaw in 1 patient with prostate cancer receiving both chemotherapy and intravenous zoledronic acid (Zometa). Bisphosphonates have been demonstrated to alter the normal bone microenvironment and appear to have direct effects on tumors as well. These changes may contribute to the development of osteonecrosis of the jaw, particularly after tooth extractions or other invasive dental procedures. 相似文献
103.
Marlon R Schneider Bettina Mayer‐Roenne Maik Dahlhoff Verena Proell Karin Weber Eckhard Wolf Reinhold G Erben 《Journal of bone and mineral research》2009,24(3):455-467
Signaling through the epidermal growth factor receptor (EGFR) by ligands such as epidermal growth factor (EGF), transforming growth factor α (TGFA), and amphiregulin (AREG) has been reported to have effects on skeletal growth. The role of betacellulin (BTC), another EGFR ligand, in skeletal development and bone metabolism is unknown. In previous experiments, transgenic mice overexpressing BTC ubiquitously under the control of the chicken β‐actin promoter (BTC‐tg) exhibited stunted growth and disproportionately sized long bones. In this study, we performed a detailed phenotypic analysis of BTC‐tg mice at 3, 6, and 9 wk of age. Osteoblastic cells from transgenic mice showed strong expression of BTC as determined by Western blots and by immunohistochemistry on bone sections. In femurs of male and female BTC‐tg mice, we found reduced longitudinal bone growth and a pronounced increase in total volumetric BMD. The increased femoral BMD was mainly caused by augmented endocortical bone apposition and subsequent cortical bone thickening. In contrast, vertebral BMD was reduced in BTC‐tg mice of both sexes. An overall similar phenotype was found in 6‐mo‐old BTC‐tg mice. The increase in cortical bone mass in the appendicular skeleton of BTC‐tg mice was largely blocked when they were crossed into the EgfrWa5 background characterized by a dominant negative EGFR. Our study showed that overexpression of BTC results in an EGFR‐dependent upregulation of cortical bone mass in the appendicular skeleton of mice, uncovering a potential novel anabolic pathway for cortical bone. 相似文献
104.
Holger F. Boehm Felix Eckstein Caecilia Wunderer Volker Kuhn Eva-Maria Lochmueller Karin Schreiber Dirk Mueller Ernst J. Rummeny Thomas M. Link 《Journal of clinical densitometry》2005,8(4):488-494
We tested the hypothesis that bone mineral density (BMD) and bone mineral content (BMC) in proximal human femur specimens in the upper neck region of interest (ROI) and femoral neck axis length (FNAL) provide a significantly better prediction of femoral bone strength than standard ROIs in vitro. BMD and BMC were measured in 110 proximal femur specimens using a standard dual-energy X-ray absorptiometry (DXA) scanner. The analysis included a new ROI in the upper neck as well as the standard ROIs. FNAL was obtained from the scan images. The specimens' failure-load was measured in a mechanical loading device, simulating a fall on the greater trochanter. For the standard ROIs, correlations between failure-load and BMD ranged from R2 = 0.64 (shaft ROI) to R2 = 0.70, p < 0.001 (femoral neck). Prediction of strength by BMD did not significantly differ from those of BMC (R2 ranging from 0.65 to 0.75, p < 0.001). In the upper neck ROI, for both BMD and BMC correlations with failure-load were higher (R2 = 0.76 and 0.81, respectively; p < 0.001). A lower, yet still significant, correlation was found between FNAL and bone strength (R2 = 0.23, p < 0.001). Normalization of failure-load with respect to FNAL did not significantly increase the correlations with densitometric measures. This study provides in vitro evidence indicating that among the ROIs of the proximal femur the newly defined upper neck ROI provides the best prediction of bone strength. Only a weak association was observed between failure load and FNAL. 相似文献
105.
Results of gastric bypass plus resection of the distal excluded gastric segment in patients with morbid obesity 总被引:7,自引:0,他引:7
Attila?CsendesEmail author Patricio?Burdiles Karin?Papapietro Juan?Carlos?Diaz Fernando?Maluenda Ana?Burgos Jorge?Rojas 《Journal of gastrointestinal surgery》2005,9(1):121-131
Surgical treatment is the procedure of choice for morbidly obese patients. Gastric bypass with a long limb Roux-en-Y anastomosis
is the "gold standard" technique for these patients. We sought to determine the early and late results of open gastric bypass
with resection of the distal excluded stomach in patients with morbid obesity. We included in this prospective study 400 patients
who were seen from September 1999 through August 2003 (311 women and 89 men; mean age, 38.5 years). The mean body mass index
of the patients was 46 kg/m2. All underwent 95% distal gastrectomy, with resection of the bypassed stomach, leaving a small
gastric pouch of 15 to 20 ml. An end-to-side gastrojejunostomy was performed with circular stapler No. 25. The length of the
Roux-en-Y loop was 125 to 150 cm. In all patients, a biopsy was taken from the liver and routine cholecystectomy was performed.
Follow-up was as long as 36 months. A barium study was performed in all patients at 5 days after surgery. Mortality and postoperative
morbidity rates were 0.5% and 4.75%, respectively, mainly due to anastomotic leak in 10 patients (2.5%). Hospital length of
stay was 7 days for 95% of the patients. Follow-up data for longer than 12 months were available in 184 patients. There was
excess body weight loss of 70% at 24 and 36 months, and there was an inverse correlation among preoperative body mass index
and the loss of weight. Anemia was present in 10%, and incisional hernia was present in 10.2%. At 1 year after surgery, the
BAROS index demonstrated very good or excellent index in 96.6% of the patients. Gastric bypass with resection of the distal
excluded segment has results very similar to those of gastric bypass alone but eliminates the potential risks of gastric bypass
such as anastomotic ulcer, gastrogastric fistula, postoperative bleeding due to peptic ulcer and gastritis, and the eventual
future development of gastric cancer. It is also possible to perform via laparoscopy, as we started to do recently. 相似文献
106.
Differential effect of BMP4 on NIH/3T3 and C2C12 cells: implications for endochondral bone formation. 总被引:4,自引:0,他引:4
Guangheng Li Hairong Peng Karin Corsi Arvydas Usas Anne Olshanski Johnny Huard 《Journal of bone and mineral research》2005,20(9):1611-1623
After intramuscular implantation, BMP4-expressing NIH/3T3 fibroblasts and BMP4-expressing C2C12 myoblasts can promote ectopic cartilage and bone formation. Fibroblasts tend to undergo chondrogenesis, whereas myoblasts primarily undergo osteogenesis. These results suggest that endochondral bone formation may involve different cell types, a finding that could have major implications for the tissue engineering of bone and cartilage. INTRODUCTION: The delivery of BMP4 through cell-based gene therapy can trigger ectopic endochondral bone formation in skeletal muscle. We hypothesized that, when stimulated with or transduced to express BMP4, different types of cells residing within skeletal muscle might participate in different stages of endochondral bone formation. MATERIALS AND METHODS: We compared the responses of a fibroblast cell line (NIH/3T3), a myoblast cell line (C2C12), primary fibroblasts, and primary myoblasts to BMP4 stimulation in vitro. We then transduced the four cell populations to express BMP4 and compared their ability to promote ectopic endochondral bone formation in skeletal muscle. RESULTS: Under the influence of BMP4 in vitro and in vivo, NIH/3T3 cells differentiated toward both chondrogenic and osteogenic lineages, whereas most C2C12 cells underwent primarily osteogenic differentiation. NIH/3T3 cells genetically modified to express BMP4 induced delayed but more robust cartilage formation than did genetically modified C2C12 cells, which promoted rapid ossification. These differences in terms of the timing and amount of cartilage and bone formation persisted even after we introduced a retrovirus encoding dominant negative Runx2 (DNRunx2) into the C2C12 cells, which interferes with the function of Runx2. Superior osteogenic potential was also displayed by the primary myoblasts in vitro and in vivo compared with the primary fibroblasts. The different proliferation abilities and differentiation potentials exhibited by these cells when influenced by BMP4 may at least partially explain the differing roles that BMP4-expressing myogenic cells and BMP4-expressing fibroblastic cells play in endochondral bone formation. CONCLUSIONS: Our findings suggest that the process of endochondral bone formation in skeletal muscle after delivery of BMP4 involves different cell types, including fibroblastic cells, which are more involved in the chondrogenic phases, and myoblastic cells, which are primarily involved in osteogenesis. These findings could have important implications for the development of tissue engineering applications focused on bone and cartilage repair. 相似文献
107.
Markus Rothenburger Karin Drebber Tonny D T Tjan Christoph Schmidt Christof Schmid Thomas Wichter Hans Heinrich Scheld Michael Deiwick 《European journal of cardio-thoracic surgery》2003,23(5):703-9; discussion 709
OBJECTIVE: Aortic valve replacement for aortic valve stenosis (AS) and regurgitation (AR) in patients with severe left ventricular (LV) dysfunction contains an increased risk. Few data are available on the outcome of such patients. METHODS: Fifty-five consecutive patients with severe LV dysfunction (ejection fraction, EF; <30%) and aortic valve replacement for AS (n=35) or AR (n=20) were investigated between 1994 and 2001. EF was 25+/-5%, mean transvalvular gradient 26+/-6mmHg (AS), aortic valve area 0.66+/-0.18cm(2) (AS), cardiac index (CI) 2.4+/-0.9l/min/m(2), enddiastolic LV diameter (LVEDD) 64+/-8mm and endsystolic LV diameters (LVESD) was 55+/-3mm. Ninety percent of patients were in New York Heart Association (NYHA) functional class III/IV at admission to the hospital. Concomitant coronary artery bypass grafts (CABG) were performed in 14 patients. Follow-up examinations including chest X-ray, echocardiography, exercise testing, were performed among survivors. RESULTS: The survival rates for AS were: 1-year 76%, 2-year 68.8%, 5-year 64.2%; for AR: 1-year 94.4%, 2-year 86.5%, 5-year 74.2%. NYHA functional class improved from 90% in class III/IV to 45 (AR group) and 24% (AS group) at follow-up (P<0.02). The LVEDD decreased to 54+/-8mm after 1 year. The EF improved to 38+/-4 (AR group) and 40+/-5% (AS group) at follow-up. CONCLUSIONS: Despite severe LV dysfunction, increased 1-year mortality especially in the AS group, aortic valve replacement was associated with improved functional status, symptoms and EF in both groups and in most patients. We, therefore, conclude that aortic valve replacement in patients with severe LV dysfunction can be performed with acceptable risk. 相似文献
108.
BACKGROUND: Many studies have demonstrated that either glutamate -methyl-d-aspartate (NMDA) receptor antagonists or opioid receptor agonists provide antinociception. Spinal coadministration of an NMDA receptor antagonist and morphine has an additive action for control of various pain states in animal models. The current study examined spinal coadministration of low doses of NMDA receptor antagonist, D-(-)-2-Amino-5-phosphonovalerate (D-APV), and mu-opioid receptor agonist, morphine sulfate (MS), in reducing visceral nociception using an acute bradykinin induced pancreatitis model in rats. METHODS: An intrathecal catheter was surgically inserted into the subarachnoid space for spinal drug administration in Sprague-Dawley rats. A laparotomy was performed for ligation and cannulation of the bile-pancreatic duct. Rats were pretreated intrathecally with artificial cerebrospinal fluid (aCSF), D-APV, MS, or combined administration of D-APV and MS. These treatments were given 30 min before noxious visceral stimulation with bradykinin injected through the bile-pancreatic catheter. Spontaneous behavioral activity tests, including cage crossing, rearing, and hind limb extension, were conducted before and after bradykinin injection into the bile-pancreatic duct to assess visceral nociception. RESULTS: Spinal pretreatment of D-APV or low doses of MS partially reduced visceral pain behaviors in this model. Pretreatments with combinations of low doses of MS (0.05-0.5 microg) and D-APV (1 microg) were maximally effective in returning all spontaneous behavioral activities to baseline. CONCLUSIONS: Spinal administration of combined doses of NMDA receptor antagonist, D-APV, and MS reversed three behavioral responses to induction of an acute pancreatitis model. These results suggest that in the clinical management of visceral pain, such as pancreatitis, restricted usage of glutamate antagonists might be useful as adjuvant potentiation at the onset of morphine therapy. 相似文献
109.
Roelen DL van den Boogaardt DE van Miert PP Koekkoek K Offringa R Claas FH 《Transplant immunology》2008,19(3-4):220-228
Dexamethason (DEX) treated DC display several features that establish them as candidates for specific allogeneic tolerance induction. We report the results of in vitro studies of polarization of the alloimmune T cell response with two types of differentially modulated human DC. Both DEX treated DC triggered by LPS for 6 h (DEX6-DC) and DEX treated DC triggered by LPS for 48 h (DEX48-DC) acquired low levels of costimulatory, adhesion, and MHC class II molecules compared with mature DC (mDC). In contrast to mDC, both DEX6-DC and DEX48-DC did not produce any IL-12. DEX6-DC were able to produce significant amounts of IL-10 whereas DEX48-DC did not actively produce IL-10. Conversely, the induction of IL-10 producing cells was significantly increased when PBL were stimulated with DEX48-DC compared with DEX6-DC. Both stimulation of PBL with DEX6-DC and DEX48-DC led to the induction of cell populations able to suppress the proliferative alloimmune response of primed T cells in a cell-cell contact independent and antigen-nonspecific manner. Tregs obtained after stimulation with DEX48-DC were also able to inhibit the IFN-gamma production of the effector cells and this effect could be blocked by anti-IL-10. Tregs induced by DEX6-DC produced similar amounts of IL-10, yet were not able to inhibit IFN-gamma production of the effector T cells, indicating a different mechanism. In summary, we show that differential modulation of DC results in the induction of different populations of regulatory T cells. 相似文献
110.
Angela J Keleher Richard L Theriault Karin M Gwyn Kelly K Hunt Carol B Stelling S Eva Singletary Frederick C Ames Thomas A Buchholz Aysegul A Sahin Henry M Kuerer 《Journal of the American College of Surgeons》2002,194(1):54-64
The management of PABC is very difficult. The incidence of PABC is low, but may be increasing because of the number of women who are becoming pregnant at a later age. More investigation is needed to understand whether the biology of PABC is different from that of breast cancer in nonpregnant women. One exciting area of further research is the potential relationship between mutations in known breast cancer susceptibility genes and breast cancer development during pregnancy. Diagnosis or PABC remains challenging because of the anatomic and physiologic changes that occur in the breast during pregnancy. Understanding the generic influences on PABC may help physicians in diagnosing this disease earlier, and understanding the tumor-receptor characteristics of PABC can help physicians deliver effective treatment. The various modalities available for treatment of PABC and their risks and benefits must be discussed openly with patients and their families. Abortion is not usually recommended. Modified radical mastectomy is the recommended treatment for PABC diagnosed during the first trimester. Neoadjuvant or adjuvant chemotherapy can be given with minimal risks to the fetus during the second or third trimester. Radiation therapy is contraindicated during pregnancy because of the potential for injury to the fetus. Breast conservation therapy, with radiation treatments given after delivery or after neoadjuvant chemotherapy, is an option for women with PABC diagnosed late in pregnancy. Once the appropriate treatment modality is chosen, its implementation must not be delayed because of the pregnancy. Most of the literature shows that women with PABC have the same survival stage for stage as nonpregnant women with breast cancer. But some studies suggest that the prognosis is worse for patients who present with advanced-stage PABC. Finally, recurrence and survival in most patients previously treated for breast cancer do not appear to be adversely affected by subsequent pregnancy. Above all, the patient with breast cancer diagnosed during pregnancy is best served by early and continued involvement of a multidisciplinary cancer treatment team. 相似文献