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41.
Transforming growth factor-beta regulation of the insulin-like growth factor binding protein-4 protease system in cultured human osteoblasts. 总被引:5,自引:0,他引:5
Christopher O Ortiz Bing-Kun Chen Laurie K Bale Michael T Overgaard Claus Oxvig Cheryl A Conover 《Journal of bone and mineral research》2003,18(6):1066-1072
IGFBP-4 is an inhibitor of IGF-I in bone. We show that TGF-beta regulates IGFBP-4 and enhances IGF-I-stimulated growth of cultured human bone cells through increased expression of an IGFBP-4 protease, PAPP-A. This effect of TGF-beta on IGF-I bioavailability may promote local bone formation. Insulin-like growth factor binding protein (IGFBP-4) proteolysis is implicated in the regulation of local insulin-like growth factor (IGF)-I bioavailability during bone remodeling. The IGFBP-4 protease secreted by normal adult human osteoblastic (hOB) cells in culture is a novel metalloproteinase, pregnancy-associated plasma protein-A (PAPP-A). We have recently identified an inhibitor of PAPP-A, the precursor form of major basic protein (proMBP). Very little is known about the molecular regulation of this IGFBP-4 protease system. In the present study, we determined the effect of transforming growth factor (TGF)-beta and IGF-II, the two most abundant growth factors in human bone, on PAPP-A and proMBP expression in primary cultures of hOB cells. Treatment with TGF-beta resulted in time- and dose-dependent increases in PAPP-A mRNA expression, with a maximal 12-fold increase after 24 h of stimulation with 10 ng/ml TGF-beta. Increased PAPP-A levels in hOB cell-conditioned medium paralleled PAPP-A gene expression. In addition, TGF-beta completely suppressed proMBP expression. Treatment of hOB cells with IGF-II had no effect on PAPP-A or proMBP gene expression. However, IGFBP-4 proteolysis in cell-free assay was dependent on IGF-II, and there was increased IGF-II-dependent IGFBP-4 protease activity in conditioned medium from hOB cells that were treated with TGF-beta. IGF-I stimulation of hOB cell proliferation was markedly enhanced by pretreatment with TGF-beta and [Leu27]IGF-II, and this enhancement was prevented with protease-resistant IGFBP-4. In summary, TGF-beta regulates IGFBP-4 proteolysis in hOB cells through increased expression of the protease, PAPP-A, and decreased expression of the inhibitor, proMBP. However, functional activation of the IGFBP-4 protease system is dependent on IGF-II, which acts at a post-translational level. These data support a model whereby local TGF-beta and IGF-II in the bone microenvironment coordinately amplify IGF-I bioavailability through controlled IGFBP-4 proteolysis, which may be a means to promote bone formation. 相似文献
42.
Piñero A Canteras M Ortiz E Martínez-Barba E Parrilla P 《Annals of surgical oncology》2008,15(10):2874-2877
Background Lymph node involvement is a very important prognostic factor for cutaneous melanoma. In this paper we try to validate a nomogram
that was created at the Memorial Sloan–Kettering Cancer Center, New York, to predict the probability of metastases in the
sentinel nodes of patients with cutaneous melanoma.
Methods Values of the following variables were collected in 218 patients with cutaneous melanoma and sentinel lymph node: age, thickness,
level of Clark, location of the lesion, and ulceration or not, and the nomogram was applied to assess the probability of sentinel
node involvement in each patient. The discrimination of the nomogram was assessed by calculating the area under the receiver
operating characteristics (ROC) curve, and to assess the accuracy of the nomogram actual probabilities were plotted against
the nomogram-calculated predicted probability.
Results The overall predictive accuracy of the nomogram was 0.869 (95% confidence interval 0.813–0.925). Mean predicted probability
of sentinel node metastasis was highly correlated to the observed risk (r = 0.953; P < 0.012).
Conclusion The nomogram is a useful diagnostic tool that provides an adequate accurate prediction of the probability of sentinel lymph
node metastases in patients with cutaneous melanoma. 相似文献
43.
Ortiz CL Mendoza MM Sempere LN Sanz JS Torres AN Barraquer EL 《Annals of plastic surgery》2007,58(3):315-320
For the last decades, the latissimus dorsi skin-muscle flap has contributed to the efficient reconstruction of the loss of skin cover (especially in breast surgery) and in long-distance tissue defects. Unfortunately, the nonuse of such an important muscle as the latissimus dorsi for the patient, as well as the resulting thickness of the flap after reconstruction, has turned it into a second choice flap. However, this flap is still indicated in the reconstruction of areas which need a great amount of cutaneous and muscular tissue. The appearance of the perforator flaps and, specifically, thoracodorsal artery perforator (TDAP) flap, has meant a radical change in relation to lower morbidity of the donor site, thus highly ranking the use of these flaps in the reconstruction for similar defects. The aim of this publication is to present our experience with the pedicled TDAP flap in a series of 17 different cases. Of those, there were 14 cases of mammary reconstruction after sparing surgery, 2 cases of axillary reconstruction following severe recurrent hidradenitis, and a case of extensive substance loss in a patient's upper limb following a severe crush injury. 相似文献
44.
A. Valdivieso J. Bustamante J.G. Uriarte P. Ruiz I. Pijoan M.J. Suarez J. Ortiz de Urbina 《Transplantation proceedings》2010,42(2):660-662
Management of patients with hepatocellular carcinoma (HCC) recurrence after liver transplantation (OLT) is not well established. We conducted a retrospective analysis of our results in the treatment of HCC recurrence after OLT Patients. The 23 HCC recurrences developed after 182 OLT performed for HCC within Milan criteria, had an average follow-up of 60 months.
Results
The median time to recurrence was 23.4 months. Surgical resection of the recurrence was possible in 11 patients, but an R-0 resection was obtained in 8 patients. Four of these 8 patients developed another recurrence, with 3 succumbing due to tumor recurrence and 1 alive at 12 months with recurrence. The other 4 patients without recurrences, include 3 who are alive at 19, 31, and 86 months and 1 who died at 32.6 months due to hepatitis C recurrence. The 3 patients with palliative resections developed recurrences. Twelve patients were rejected for surgery: 8 were treated symptomatically, 2 with systemic chemotherapy, and 2 with everolimus and sorafenib. This last treatment was also prescribed for 2 patients after R-0 surgery who are alive at 19 and 31 months and for 1 patient after R-1 surgery who is alive at 19 months. Of 15 patients who died, 13 succumbed to HCC recurrence. The average survival from transplantation was 61.7 ± 37.5 and 48 ± 34.3 months for patients without and with recurrence, respectively (P < .001). The survival from the recurrence was significantly higher among patients with R-0 surgery: 32.3 ± 21.5 versus 11.9 ± 6.9 months (P = .006).Conclusions
HCC recurrence after OLT of patients within Milan criteria was low but had a great impact on survival. Few cases are amenable to R-0 resection, but when possible it was associated with a significantly increased survival, although with an high incidence of a new recurrence. There is a rationale for the use of sorafenib and mammalian target of rapamycin based immunosuppression, which warrants randomized studies. 相似文献45.
EH Gemmill DJ Humes JA Catton 《Annals of the Royal College of Surgeons of England》2015,97(3):173-179
Introduction
Fast track methodology or enhanced recovery schemes have gained increasing popularity in perioperative care. While evidence is strong for colorectal surgery, its importance in gastric and oesophageal surgery has yet to be established. This article reviews the evidence of enhanced recovery schemes on outcome for this type of surgery.Methods
A systematic literature search was conducted up to March 2014. Studies were retrieved and analysed using predetermined criteria.Results
From 34 articles reviewed, 18 eligible studies were identified: 7 on gastric and 11 on oesophageal resection. Three randomised controlled trials, five case-controlled studies and ten case series were identified. The reported protocols included changes to each stage of the patient journey from pre to postoperative care. The specific focus following oesophageal resections was on early mobilisation, a reduction in intensive care unit stay, early drain removal and early (or no) contrast swallow studies. Following gastric resections, the emphasis was on reducing epidural anaesthesia along with re-establishing oral intake in the first three postoperative days and early removal of nasogastric tubes.In the papers reviewed, mortality rates following fast track surgery were 0.8% (9/1,075) for oesophageal resection and 0% (0/329) for gastric resection. The reported morbidity rate was 16.5% (54/329) following gastric resection and 38.6% (396/1,075) following oesophageal resection. Length of stay was reduced in both groups compared with conventional recovery groups in comparative studies.Conclusions
The evidence for enhanced recovery schemes following gastric and oesophageal resection is weak, with only three (low volume) published randomised controlled trials. However, the enhanced recovery approach appears safe and may be associated with a reduction in length of stay. 相似文献46.
Eva Tabernero Huguet Borja Ortiz de Urbina Antia Beatriz González Quero Elena Garay Llorente Joseba Andia Iturrate Silvia Pérez Fernández Ana Gómez Larrauri Milagros Iriberri Pascual 《Archivos de bronconeumologia》2021,57(5):345-350
IntroductionNECPAL is a tool for identification of patients with advanced chronic disease in need of palliative care. The main objective of the study is to know the prevalence of patients with palliative needs in an acute respiratory ward in a Spanish tertiary hospital using NECPAL. A second objective of the study is to know the annual mortality rate of these patients.Materials and methodsCross sectional study and prospective monitoring of a cohort identified as palliative patients with the NECPAL tool for 12 months. Patient identification was performed in patients admitted to the respiratory ward of our hospital for longer than 3 days. We have assessed the annual vital status (deceased or not deceased) of patients and have recorded demographics, clinical and functional data, as well as the use of healthcare resources.ResultsWe monitored a cohort of 363 patients. Of them, 87 patients (24.3%) (IC 95% 19–30) were identified as NECPAL positive. 60% of patients (n = 64) died within 12 months of their admission. There was no significant difference in the mortality ratio of oncologic versus non oncologic patients. In a multivariable analysis, mortality was associated with demand by patients or relatives for palliative care and with the presence of specific disease progression markers or indicators.Conclusionsprevalence of patients with palliative needs in acute respiratory wards is high (one out of four patients). 60% of the patients identified as NECPAL positive in our cohort died in the first 12 months. Training of healthcare professionals as well as availability of appropriate resources are indispensable factors to improve care of this population. 相似文献
47.
P. Trunečka O. Boillot D. Seehofer A. D. Pinna L. Fischer B.‐G. Ericzon R. I. Troisi U. Baccarani J. Ortiz de Urbina W. Wall 《American journal of transplantation》2010,10(10):2313-2323
The efficacy and safety of dual‐therapy regimens of twice‐daily tacrolimus (BID; Prograf) and once‐daily tacrolimus (QD; Advagraf) administered with steroids, without antibody induction, were compared in a multicenter, 1:1‐randomized, two‐arm, parallel‐group study in 475 primary liver transplant recipients. A double‐blind, double‐dummy 24‐week period was followed by an open extension to 12 months posttransplant. The primary endpoint, event rate of biopsy‐proven acute rejection (BPAR) at 24 weeks, was 33.7% for tacrolimus BID versus 36.3% for tacrolimus QD (Per‐protocol set; p = 0.512; treatment difference 2.6%, 95% confidence interval ?7.3%, 12.4%), falling within the predefined 15% noninferiority margin. At 12 months, BPAR episodes requiring treatment were similar for tacrolimus BID and QD (28.1% and 24.7%). Twelve‐month patient and graft survival was 90.8% and 85.6% for tacrolimus BID and 89.2% and 85.3% for tacrolimus QD. Adverse event (AE) profiles were similar for both tacrolimus BID and QD with comparable incidences of AEs and serious AEs. Tacrolimus QD was well tolerated with similar efficacy and safety profiles to tacrolimus BID. 相似文献
48.
Joan Figueras Martin Prieto Angel Bernardos Antoni Rimola Francisco Suárez Jorge Ortiz de Urbina Valentín Cuervas-Mons Manuel de la Mata 《Transplant international》2006,19(8):641-648
Steroid-free immunosuppressive regimens reduce corticosteroid-related side effects in liver transplant recipients although their efficacy is very variable. We evaluated the efficacy and safety of a steroid-free regimen in a 6-month, open-label, multicenter, pilot study, which involved 102 liver transplant patients treated with daclizumab (2 mg/kg within 6 h following transplant and 1 mg/kg on day 7), mycophenolate mofetil (MMF, 1 g b.i.d) and tacrolimus (trough levels of 5-15 ng/ml in the first month and 5-10 ng/ml thereafter). One intra-operative dose of methylprednisolone was administered. At 6 months, the acute rejection rate was 9.8%, and patient and graft survival rates were 96% and 95%, respectively. Acute rejection rates were similar for hepatitis C-positive patients (8.6%) and hepatitis C-negative patients (10.4%). Infections occurred in 22% of patients; most cases were considered mild or moderate. Post-transplantation hypertension and diabetes mellitus developed in 37% and 14% of patients, respectively, during the study period, but were markedly less frequent (8% and 6%, respectively) at 6 months. Hypercholesterolemia was observed in only 2% of patients. In conclusion, the steroid-free immunosuppressive regimen of daclizumab, MMF, and tacrolimus effectively prevents acute rejection after liver transplantation without decreasing safety. 相似文献
49.
The sacrum: pathologic spectrum, multimodality imaging, and subspecialty approach. 总被引:10,自引:0,他引:10
The sacrum is a structure that is imaged by both general and subspecialty radiologists. A wide variety of disease processes can involve the sacrum either focally or as part of a systemic process. Plain radiographs, although limited in evaluation of the sacrum, should be carefully examined when abnormalities of the sacrum are suspected. Cross-sectional imaging, particularly computed tomography and magnetic resonance (MR) imaging, plays a crucial role in identification, localization, and characterization of sacral lesions. Congenital lesions of the sacrum, including sacral agenesis and meningocele, are optimally imaged with MR. The most common sacral neoplasm is metastatic disease. Primary neoplasms of the sacrum, which include giant cell tumor, chordoma, and teratoma, are infrequent. Infection of the sacrum or sacroiliac joint is most often due to contiguous spread from a suppurative focus. A wide variety of arthritic disorders such as ankylosing spondylitis and osteoarthritis can involve the sacroiliac joints as part of a localized or systemic process. Sacral fractures related to acute trauma or repetitive stress are difficult to diagnose and treat. Knowledge of these abnormalities and familiarity with the imaging of these processes will allow radiologists of all subspecialties to contribute to the diagnosis and management of sacral disorders. 相似文献
50.
Damodaran Shivashankar Bullock Brenna Ekwenna Obi Nayebpour Mehdi Koizumi Naoru Sindhwani Puneet Ortiz Jorge 《International urology and nephrology》2021,53(3):439-446
International Urology and Nephrology - Delayed graft function (DGF) is a manifestation of acute kidney injury uniquely framed within the transplant process and a predictor of poor long-term graft... 相似文献