Annexin 1 mimetic peptide protects against renal ischemia/reperfusion injury in rats

Inflammation is currently recognized as a key mechanism in the pathogenesis of renal ischemia-reperfusion (I/R) injury. The importance of infiltrating neutrophil, lymphocytes, and macrophage in this kind of injury has been assessed with conflicting results. Annexin 1 is a protein with potent neutrophil anti-migratory activity. In order to evaluate the effects of annexin A1 on renal I/R injury, uninephrectomized rats received annexin A1 mimetic peptide Ac2-26 (100 mu g) or vehicle before 30 min of renal artery clamping and were compared to sham surgery animals. Annexin A1 mimetic peptide granted a remarkable protection against I/R injury, preventing glomerular filtration rate and urinary osmolality decreases and acute tubular necrosis development. Annexin A1 infusion aborted neutrophil extravasation and attenuated macrophage infiltration but did not prevent tissue lymphocyte traffic. I/R increased annexin A1 expression (assessed by transmission electron microscopy) in renal epithelial cells, which was attenuated by exogenous annexin A1 infusion. Additionally, annexin A1 reduced I/R injury in isolated proximal tubules suspension. Annexin A1 protein afforded striking functional and structural protection against renal I/R. These results point to an important role of annexin A1 in the epithelial cells defense against I/R injury and indicate that neutrophils are key mediators for the development of tissue injury after renal I/R. If these results were confirmed in clinical studies, annexin A1 might emerge as an important tool to protect against I/R injury in renal transplantation and in vascular surgery.

Unexplained sudden death in patients on the waiting list for renal transplantation

Background. The incidence of unexplained sudden death (SD) and the factors involved in its occurrence in patients with chronic kidney disease are not well known. Methods. We investigated the incidence and the role of co-morbidities in unexplained SD in 1139 haemodialysis patients on the renal transplant waiting list. Results. Forty-four patients died from SD of undetermined causes (20% of all deaths; 3.9 deaths/1000 patients per year), while 178 died from other causes and 917 survived. SD patients were older and likely to have diabetes, hypertension, past/present cardiovascular disease, higher left ventricular mass index, and lower ejection fraction. Multivariate analysis showed that cardiovascular disease of any type was the only independent predictor of SD (P = 0.0001, HR = 2.13, 95% CI 1.46-3.22). Alterations closely associated with ischaemic heart disease like angina, previous myocardial infarction and altered myocardial scan were not independent predictors of SD. The incidence of unexplained SD in these haemodialysis patients is high and probably a consequence of pre-existing cardiovascular disease. Conclusions. Factors influencing SD in dialysis patients are not substantially different from factors in the general population. The role played by ischaemic heart disease in this context needs further evaluation.

Validation of a strategy to diagnose coronary artery disease and predict cardiac events in high-risk renal transplant candidates

Background We validated a strategy for diagnosis of coronary artery disease ( CAD) and prediction of cardiac events in high-risk renal transplant candidates ( at least one of the following: age >= 50 years, diabetes, cardiovascular disease). Methods A diagnosis and risk assessment strategy was used in 228 renal transplant candidates to validate an algorithm. Patients underwent dipyridamole myocardial stress testing and coronary angiography and were followed up until death, renal transplantation, or cardiac events. Results The prevalence of CAD was 47%. Stress testing did not detect significant CAD in 1/3 of patients. The sensitivity, specificity, and positive and negative predictive values of the stress test for detecting CAD were 70, 74, 69, and 71%, respectively. CAD, defined by angiography, was associated with increased probability of cardiac events [log-rank: 0.001; hazard ratio: 1.90, 95% confidence interval (CI): 1.29-2.92]. Diabetes (P=0.03; hazard ratio: 1.58, 95% CI: 1.06-2.45) and angiographically defined CAD (P=0.03; hazard ratio: 1.69, 95% CI: 1.08-2.78) were the independent predictors of events. Conclusion The results validate our observations in a smaller number of high-risk transplant candidates and indicate that stress testing is not appropriate for the diagnosis of CAD or prediction of cardiac events in this group of patients. Coronary angiography was correlated with events but, because less than 50% of patients had significant disease, it seems premature to recommend the test to all high-risk renal transplant candidates. The results suggest that angiography is necessary in many high-risk renal transplant candidates and that better noninvasive methods are still lacking to identify with precision patients who will benefit from invasive procedures. Coron Artery Dis 21: 164-167 (C) 2010 Wolters Kluwer Health vertical bar Lippincott Williams & Wilkins.

Durable Complete Responses in Metastatic Colorectal Cancer Treated with Chemotherapy Alone

Background/Purpose: The median survival for patients with metastatic colorectal cancer (mCRC) has progressively increased over the past decades. Since the introduction of 5-fluorouracil (5-FU)-based chemotherapy, followed by hepatic resection of metastases, and more recently the adoption of newer chemotherapeutic regimens associated with targeted therapy, the gains are getting more substantial. Despite the recognition of the potential for long-term survival after surgical resection of metastatic disease, long-term survival data to determine the potential curative role of chemotherapy alone is lacking. Methods: We performed a retrospective review of 2751 patients who presented with mCRC at The MD Anderson Cancer Center from 1990 through 2003. Patients alive at 5 years who achieved complete response with chemotherapy and were not submitted to any surgical or interventional procedures directed to the metastatic sites were included in the analysis. Results: The 5-year overall survival rate for all patients with mCRC during this period was 10.8%. Among these long-term survivors, 2.2% achieved a sustained complete response after chemotherapy (all 6 with fluoropyrimidines and 2 with irinotecan) as the only treatment modality and were without evidence of disease until the last follow-up visit (median of 10.3 years). This number corresponds to 0.24% (6 of 2541) of all patients with mCRC included in this review. Conclusion: Cure with chemotherapy alone is possible for a very small number of patients with metastatic colorectal cancer. Improved therapies are increasing complete response rates, but the impact of modern chemotherapy on durable complete responses will require additional follow up.

Phase II Trial of Infusional Fluorouracil, Irinotecan, and Bevacizumab for Metastatic Colorectal Cancer: Efficacy and Circulating Angiogenic Biomarkers Associated With Therapeutic Resistance

Purpose We investigated the efficacy of fluorouracil (FU), leucovorin, irinotecan, and bevacizumab (FOLFIRI + B) in a phase II trial in patients previously untreated for metastatic colorectal cancer (mCRC), and changes during treatment in plasma cytokines and angiogenic factors (CAFs) as potential markers of treatment response and therapeutic resistance. Patients and Methods We conducted a phase II, two-institution trial of FOLFIRI + B. Each 14-day cycle consisted of bevacizumab (5 mg/kg), irinotecan (180 mg/m(2)), bolus FU (400 mg/m(2)), and leucovorin (400 mg/m(2)) followed by a 46-hour infusion of FU (2,400 mg/m(2)). Levels of 37 CAFs were assessed using multiplex-bead assays and enzyme-linked immunosorbent assay at baseline, during treatment, and at the time of progressive disease (PD). Results Forty-three patients were enrolled. Median progression-free survival (PFS), the primary end point of the study, was 12.8 months. Median overall survival was 31.3 months, with a response rate of 65%. Elevated interleukin-8 at baseline was associated with a shorter PFS (11 v 15.1 months, P = .03). Before the radiographic development of PD, several CAFs associated with angiogenesis and myeloid recruitment increased compared to baseline, including basic fibroblast growth factor (P = .046), hepatocyte growth factor (P = .046), placental growth factor (P < .001), stromal-derived factor-1 (P = .04), and macrophage chemoattractant protein-3 (P < .001). Conclusion Efficacy and tolerability of FOLFIRI + B appeared favorable to historical controls in this single arm study. Before radiographic progression, there was a shift in balance of CAFs, with a rise in alternate pro-angiogenic cytokines and myeloid recruitment factors in subsets of patients that may represent mechanisms of resistance.

Renal Cell Carcinoma: T1 and T2 Signal Intensity Characteristics of Papillary and Clear Cell Types Correlated with Pathology

OBJECTIVE. The objective of our study was to describe the T1 and T2 signal intensity characteristics of papillary renal cell carcinoma (RCC) and clear cell RCC with pathologic correlation. MATERIALS AND METHODS. Of 539 RCCs, 49 tumors (21 papillary RCCs and 28 clear cell RCCs) in 45 patients were examined with MRI. Two radiologists retrospectively and independently assessed each tumor`s T1 and T2 signal intensity qualitatively and quantitatively (i.e., the signal intensity [SI] ratio [tumor SI/renal cortex SI]). Of the 49 tumors, 37 (76%) were assessed for pathology features including tumor architecture and the presence of hemosiderin, ferritin, necrosis, and fibrosis. MRI findings and pathology features were correlated. Statistical methods included summary statistics and Wilcoxon`s rank sum test for signal intensity, contingency tables for assessing reader agreement, concordance rate between the two readers with 95% CIs, and Fisher`s exact test for independence, all stratified by RCC type. RESULTS. Papillary RCCs and clear cell RCCs had a similar appearance and signal intensity ratio on T1-weighted images. On T2-weighted images, most papillary RCCs were hypointense (reader 1, 13/21; reader 2, 14/21), with an average mean signal intensity ratio for both readers of 0.67 +/- 0.2, and none was hyperintense, whereas most clear cell RCCs were hyperintense (reader 1, 21/28; reader 2, 17/28), with an average mean signal intensity ratio for both readers of 1.41 +/- 0.4 (p < 0.05). A tumor T2 signal intensity ratio of <= 0.66 had a specificity of 100% and sensitivity of 54% for papillary RCC. Most T2 hypointense tumors exhibited predominant papillary architecture; most T2 hyperintense tumors had a predominant nested architecture (p < 0.05). CONCLUSION. On T2-weighted images, most papillary RCCs are hypointense and clear cell RCCs, hyperintense. The T2 hypointense appearance of papillary RCCs correlated with a predominant papillary architecture at pathology.

Validation of plasma clearance of (51)Cr-EDTA in adult renal transplant recipients: comparison with inulin renal clearance

Plasma clearance of (51)Cr-EDTA ((51)Cr-EDTA-Cl) is an alternative method to evaluate glomerular filtration rate (GFR). This study aimed to investigate the concordance between (51)Cr-EDTA-Cl and renal inulin clearance (In-Cl) in renal transplant recipients as well to determine the repeatability of (51)Cr-EDTA-Cl in kidney donors. Forty four kidney recipients and 22 kidney donors were enrolled. Simultaneous measurements of (51)Cr-EDTA-Cl and In-Cl were performed. A single dose of 3.7MBq of (51)Cr-EDTA was injected and the plasma disappearance curve was created by taking blood samples at 2, 4, 6 and 8 h after injection. Bland and Altman statistical approach was used to quantify the agreement between In-Cl and (51)Cr-EDTA-Cl and to determine the better concordance between all possibilities of measure for the (51)Cr-EDTA-Cl. The mean of In-Cl was 44.5 +/- 17.9 ml/min/1.73 m(2). There was a positive correlation between In-Cl and all possible measurements of (51)Cr-EDTA-Cl. (51)Cr-EDTA-Cl with two samples taken at 4 and 8 h or at 4 and 6 h presenting the narrow limits of agreement and a difference (bias) of 2.8 and 2.7 ml/min, respectively. Two plasma sampling for (51)Cr-EDTA-Cl was a reliable method to measure GFR compared with In-Cl and comprises a suitable method to be used in kidney transplanted patients.

Sonographic Diagnosis of a Ureteral Inguinal Hernia in a Renal Transplant

Complications related to renal transplants have been widely reported in the literature. The most common complications include acute tubular necrosis, rejection, perirenal fluid collections, vascular complications, and urinary tract obstruction, which are promptly identified by imaging studies. Here we report a case of a patient with a rare cause of obstruction: a ureteral inguinal hernia. This is the sixth report of this condition, and, to our knowledge, no previous case has been reported in which sonography played an important role in promptly identifying the underlying condition and allowing additional less hazardous studies, therefore aiding case management.

Expression of heterochromatin protein 1 in the primary tumor of breast cancer patients in the presence or absence of occult metastatic cells in the bone marrow

Gene silencing may occur in breast cancer samples from patients presenting with occult metastatic cells in the bone marrow and one mechanism regulating gene suppression is heterochromatin formation. We have studied whether members of the heterochromatin protein 1 family Hp1(Hs alpha), Hp1(Hs beta) and Hp1(Hs gamma) which take part in chromatin packaging and gene expression regulation, were differentially expressed in tumors from patients with and without occult metastatic cells in their bone marrow. Tumor samples and bone marrow aspirates were obtained from 37 breast cancer patients. Median age was 63 years and 68% of the patients presented with clinical stage I/II disease. Presence of occult metastatic cells in bone marrow was detected through keratin-19 expression by nested RT-PCR in samples from 20 patients (54.1%). The presence of occult metastatic cells in bone marrow was not associated with node involvement, histological grade, estrogen receptor and ERBB2 immunoexpression. Relative gene expression of HP1(Hs alpha), HP1(Hs beta) and HP1(Hs gamma) was determined by real-time RT-PCR and did not vary according to the presence of occult metastatic cells in bone marrow. In addition, the combined expression of these three transcripts could not be used to classify samples according to the presence of bone marrow micrometastasis. Our work indicates that regulation of heterochromatin formation through HP1 family members may not be the sole mechanism implicated in the metastatic process to the bone marrow. (Int J Biol Markers 2008; 23: 219-24)

Polymyxin B and colistimethate are comparable as to efficacy and renal toxicity

We compared 41 patients who received colistimethate with 41 who received polymyxin B for the treatment of serious infections caused by carbapenem-resistant Acinetobacter spp. and found both polymyxins have similar efficacy and toxicity. (C) 2009 Elsevier Inc. All rights reserved.

Vitamin D intoxication: a cause of hypocalcaemia and acute renal failure in a HIV patient

Hypercalcaemia in patients with HIV infection is usually associated with specific conditions such as lymphoma and granulomatous diseases. We described a case of severe hypercalcaemia consequent to vitamin D intoxication and secondary renal failure in a HIV patient under tenofovir using. Serum creatinine and calcium returned to near normal levels after vitamin D discontinuation, saline and furosemide administration. Some aspects of the drug-induced nephropathy are discussed.

Arginase-1 A New Immunohistochemical Marker of Hepatocytes and Hepatocellular Neoplasms

The distinction of hepatocellular carcinoma (HCC) from metastatic tumor in the liver often presents a diagnostic challenge that carries significant impact on prognostication and therapy. The number of diagnostically useful immunohistochemical markers of hepatocytes is limited to hepatocyte paraffin antigen (HepPar-1), polyclonal carcinoembryonic antigen, and CD10, with alpha-fetoprotein and glypican-3 labeling HCCs. Arginase-1 (Arg-1) is a binuclear manganese metalloenzyme that catalyzes the hydrolysis of arginine to ornithine and urea. We used immunohistochemistry to compare the sensitivity of Arg-1 to that of HepPar-1 in 151 HCCs. We found that the overall sensitivities of Arg-1 and HepPar-1 are 96.0% and 84.1%, respectively. The sensitivities of Arg-1 in well, moderately, and poorly differentiated HCCs are 100%, 96.2%, and 85.7%, respectively, whereas, in comparison, HepPar-1 demonstrated sensitivities of 100%, 83.0%, and 46.4% for well, moderately, and poorly differentiated tumors, respectively. There were no HCCs in our study that were reactive for HepPar-1 but nonreactive for Arg-1. We also examined Arg-1 expression in nonhepatocellular tumors, including many that are potential mimics of HCC (renal cell carcinomas, neuroendocrine tumors, melanomas, gastric adenocarcinomas, and adrenocortical carcinomas) and found that only 2 non-HCC tumors were reactive for Arg-1. Arg-1 represents a sensitive and specific marker of benign and malignant hepatocytes that may ultimately prove to be a useful diagnostic tool in routine surgical pathology practice.

C4d staining in post-reperfusion renal biopsy is not useful for the early detection of antibody-mediated rejection when CDC crossmatching is negative

Background. Sensitized patients (pts) may develop acute antibody-mediated rejection (AMR) due to preformed donor-specific antibodies, undetected by pre-transplant complement-dependent cytotoxicity (CDC) crossmatch (XM). We hypothesized that C4d staining in 1-h post-reperfusion biopsies (1-h Bx) could detect early complement activation in the renal allograft due to preformed donor-specific antibodies. Methods. To test this hypothesis, renal transplants (n = 229) performed between June 2005 and December 2007 were entered into a prospective study of 1-h Bx and stained for C4d by immunofluorescence. Transplants were performed against a negative T-cell CDC-XM with the exception of three cases with a positive B-cell XM. Results. All 229 1-h Bx stained negative for C4d. Fourteen pts (6%) developed AMR. None of the 14 protocol 1-h Bx stained positive for C4d in peritubular capillaries (PTC). However, all indication biopsies-that diagnosed AMR-performed at a median of 8 days after transplantation stained for C4d in PTC. Conclusions. These data show that C4d staining in 1-h Bx is, in general, not useful for the early detection of AMR when CDC-XM is negative.

Negative Anti-C1q Antibody Titers May Influence Therapeutic Decisions and Reduce the Number of Renal Biopsies in Systemic Lupus Erythematosus

In a cross-sectional study involving 62 patients with systemic lupus erythematosus (SLE), we found that patients with biopsy-proven lupus nephritis (LN) had higher titers of anti-C1q antibodies than active SLE without nephritis patients. Anti-C1q was associated with a negative predictive value of 94.59%, a positive predictive value of 52%, a sensitivity of 86.66% and a specificity of 74.47% for the diagnosis of LN. We conclude that high titers of anti-C1q antibodies are strongly associated with the presence of active LN, and the negative predictive value of this test for diagnosing LN is very high; therefore, it can influence therapeutic decisions and reduce the number of renal biopsies in patients with SLE. Copyright (C) 2011 S. Karger AG, Basel