Citations

Background— Atherosclerotic renal artery stenosis (ARAS) is known to reduce renal blood flow, glomerular filtration rate (GFR) and amplify kidney hypoxia, but the relationships between these factors and tubulointerstitial injury in the poststenotic kidney are poorly understood. The purpose of this study was to examine the effect of renal revascularization in ARAS on renal tissue hypoxia and renal injury. Methods and Results— Inpatient studies were performed in patients with ARAS (n=17; >60% occlusion) before and 3 months after stent revascularization, or in patients with essential hypertension (n=32), during fixed Na + intake and angiotensin converting enzyme/angiotensin receptors blockers Rx. Single kidney cortical, medullary perfusion, and renal blood flow were measured using multidetector computed tomography, and GFR by iothalamate clearance. Tissue deoxyhemoglobin levels ( R 2 *) were measured by blood oxygen level–dependent MRI at 3T, as was fractional kidney hypoxia (percentage of axial area with R 2 *>30/s). In addition, we measured renal vein levels of neutrophil gelatinase–associated lipocalin, monocyte chemoattractant protein-1, and tumor necrosis factor-α. Pre-stent single kidney renal blood flow, perfusion, and GFR were reduced in the poststenotic kidney. Renal vein neutrophil gelatinase–associated lipocalin, tumor necrosis factor-α, monocyte chemoattractant protein-1, and fractional hypoxia were higher in untreated ARAS than in essential hypertension. After stent revascularization, fractional hypoxia fell ( P <0.002) with increased cortical perfusion and blood flow, whereas GFR and neutrophil gelatinase–associated lipocalin, monocyte chemoattractant protein-1, and tumor necrosis factor-α remained unchanged. Conclusions— These data demonstrate that despite reversal of renal hypoxia and partial restoration of renal blood flow after revascularization, inflammatory cytokines and injury biomarkers remained elevated and GFR failed to recover in ARAS. Restoration of vessel patency alone failed to reverse tubulointerstitial damage and partly explains the limited clinical benefit of renal stenting. These results identify potential therapeutic targets for recovery of kidney function in renovascular disease.

Abstract Background: Ovarian carcinoma is composed of five major histologic types, which associate with outcome and predict therapeutic response. Our aim was to evaluate histologic type assessments across the centers participating in the Ovarian Tumor Tissue Analysis (OTTA) consortium using an immunohistochemical (IHC) prediction model. Methods: Tissue microarrays (TMA) and clinical data were available for 524 pathologically confirmed ovarian carcinomas. Centralized IHC was conducted for ARID1A, CDKN2A, DKK1, HNF1B, MDM2, PGR, TP53, TFF3, VIM, and WT1, and three histologic type assessments were compared: the original pathologic type, an IHC-based calculated type (termed TB_COSPv2), and a WT1-assisted TMA core review. Results: The concordance between TB_COSPv2 type and original type was 73%. Applying WT1-assisted core review, the remaining 27% discordant cases subdivided into unclassifiable (6%), TB_COSPv2 error (6%), and original type error (15%). The largest discordant subgroup was classified as endometrioid carcinoma by original type and as high-grade serous carcinoma (HGSC) by TB_COSPv2. When TB_COSPv2 classification was used, the difference in overall survival of endometrioid carcinoma compared with HGSC became significant [RR 0.60; 95% confidence interval (CI), 0.37–0.93; P = 0.021], consistent with previous reports. In addition, 71 cases with unclear original type could be histologically classified by TB_COSPv2. Conclusions: Research cohorts, particularly those across different centers within consortia, show significant variability in original histologic type diagnosis. Our IHC-based reclassification produced more homogeneous types with respect to outcome than original type. Impact: Biomarker-based classification of ovarian carcinomas is feasible, improves comparability of results across research studies, and can reclassify cases which lack reliable original pathology. Cancer Epidemiol Biomarkers Prev; 22(10); 1677–86. ©2013 AACR.

Abstract The critical role of the microbiology laboratory in infectious disease diagnosis calls for a close, positive working relationship between the physician and the microbiologists who provide enormous value to the health care team. This document, developed by both laboratory and clinical experts, provides information on which tests are valuable and in which contexts, and on tests that add little or no value for diagnostic decisions. Sections are divided into anatomic systems, including Bloodstream Infections and Infections of the Cardiovascular System, Central Nervous System Infections, Ocular Infections, Soft Tissue Infections of the Head and Neck, Upper Respiratory Infections, Lower Respiratory Tract infections, Infections of the Gastrointestinal Tract, Intraabdominal Infections, Bone and Joint Infections, Urinary Tract Infections, Genital Infections, and Skin and Soft Tissue Infections; or into etiologic agent groups, including Tickborne Infections, Viral Syndromes, and Blood and Tissue Parasite Infections. Each section contains introductory concepts, a summary of key points, and detailed tables that list suspected agents; the most reliable tests to order; the samples (and volumes) to collect in order of preference; specimen transport devices, procedures, times, and temperatures; and detailed notes on specific issues regarding the test methods, such as when tests are likely to require a specialized laboratory or have prolonged turnaround times. There is redundancy among the tables and sections, as many agents and assay choices overlap. The document is intended to serve as a reference to guide physicians in choosing tests that will aid them to diagnose infectious diseases in their patients.

Abstract Purpose: MUC1 is a tumor-associated antigen that is aberrantly expressed in cancer and inflammatory bowel disease (IBD). Even though immune cells express low MUC1 levels, their modulations of MUC1 are important in tumor progression. Consistent with previous clinical data that show increased myeloid-derived suppressor cells (MDSCs) in IBD, we now show that downregulation of MUC1 on hematopoietic cells increases MDSCs in IBD, similar to our data in tumor-bearing mice. We hypothesize that MDSC expansion in IBD is critical for tumor progression. Experimental Design: To mechanistically confirm the linkage between Muc1 downregulation and MDSC expansion, we generated chimeric mice that did not express Muc1 in the hematopoietic compartment (KO→WT). These mice were used in two models of colitis and colitis-associated cancer (CAC) and their responses were compared with wild-type (WT) chimeras (WT→WT). Results: KO→WT mice show increased levels of MDSCs during colitis and increased protumorigenic signaling in the colon during CAC, resulting in larger colon tumors. RNA and protein analysis show increased upregulation of metalloproteinases, collagenases, defensins, complements, growth factors, cytokines, and chemokines in KO→WT mice as compared with WT→WT mice. Antibody-mediated depletion of MDSCs in mice during colitis reduced colon tumor formation during CAC. Conclusion: Development of CAC is a serious complication of colitis and our data highlight MDSCs as a targetable link between inflammation and cancer. In addition, the lack of MUC1 expression on MDSCs can be a novel marker for MDSCs, given that MDSCs are still not well characterized in human cancers. Clin Cancer Res; 19(18); 5039–52. ©2013 AACR.

Abstract The critical role of the microbiology laboratory in infectious disease diagnosis calls for a close, positive working relationship between the physician and the microbiologists who provide enormous value to the health care team. This document, developed by both laboratory and clinical experts, provides information on which tests are valuable and in which contexts, and on tests that add little or no value for diagnostic decisions. Sections are divided into anatomic systems, including Bloodstream Infections and Infections of the Cardiovascular System, Central Nervous System Infections, Ocular Infections, Soft Tissue Infections of the Head and Neck, Upper Respiratory Infections, Lower Respiratory Tract infections, Infections of the Gastrointestinal Tract, Intraabdominal Infections, Bone and Joint Infections, Urinary Tract Infections, Genital Infections, and Skin and Soft Tissue Infections; or into etiologic agent groups, including Tickborne Infections, Viral Syndromes, and Blood and Tissue Parasite Infections. Each section contains introductory concepts, a summary of key points, and detailed tables that list suspected agents; the most reliable tests to order; the samples (and volumes) to collect in order of preference; specimen transport devices, procedures, times, and temperatures; and detailed notes on specific issues regarding the test methods, such as when tests are likely to require a specialized laboratory or have prolonged turnaround times. There is redundancy among the tables and sections, as many agents and assay choices overlap. The document is intended to serve as a reference to guide physicians in choosing tests that will aid them to diagnose infectious diseases in their patients.

Transforming growth factor β (TGFβ) family ligands initiate a cascade of events capable of modulating cellular growth and differentiation. The receptors responsible for transducing these cellular signals are referred to as the type I and type II TGFβ receptors. Ligand binding to the type II receptor results in the transphosphorylation and activation of the type I receptor. This heteromeric complex then propagates the signal(s) to downstream effectors. There is presently little data concerning the fate of TGFβ receptors after ligand binding, with conflicting reports indicating no change or decreasing cell surface receptor numbers. To address the fate of ligand-activated receptors, we have used our previously characterized chimeric receptors consisting of the ligand binding domain from the granulocyte/macrophage colony-stimulating factor α or β receptor fused to the transmembrane and cytoplasmic domain of the type I or type II TGFβ receptor. This system not only provides the necessary sensitivity and specificity to address these types of questions but also permits the differentiation of endocytic responses to either homomeric or heteromeric intracellular TGFβ receptor oligomerization. Data are presented that show, within minutes of ligand binding, chimeric TGFβ receptors are internalized. However, although all the chimeric receptor combinations show similar internalization rates, receptor down-regulation occurs only after activation of heteromeric TGFβ receptors. These results indicate that effective receptor down-regulation requires cross-talk between the type I and type II TGFβ receptors and that TGFβ receptor heteromers and homomers show distinct trafficking behavior.

Morbidity and mortality attributable to hypertension are higher in black essential hypertensive (EH) compared with white EH patients, possibly related to differential effects on vascular injury and repair. Although circulating endothelial progenitor cells (EPCs) preserve endothelial integrity, inflammatory endothelial cells (IECs) detach from sites of injury and represent markers of vascular damage. We hypothesized that blood levels of IECs and inflammatory markers would be higher in black EH compared with white EH patients. Inferior vena cava and renal vein levels of CD34+/KDR+ (EPC) and VAP-1+ (IEC) cells were measured by fluorescence-activated cell sorting in white EH and black EH patients under fixed sodium intake and blockade of the renin–angiotensin system, and compared with systemic levels in normotensive control subjects (n=19 each). Renal vein and inferior vena cava levels of inflammatory cytokines and EPC homing factors were measured by Luminex. Blood pressure, serum creatinine, lipids, and antihypertensive medications did not differ between white and black EH patients, and EPC levels were decreased in both. Circulating IEC levels were elevated in black EH patients, and inversely correlated with EPC levels ( R 2 =0.58; P =0.0001). Systemic levels of inflammatory cytokines and EPC homing factors were higher in black EH compared with white EH patients, and correlated directly with IECs. Renal vein inflammatory cytokines, EPCs, and IECs did not differ from their circulating levels. Most IECs expressed endothelial markers, fewer expressed progenitor cell markers, but none showed lymphocyte or phagocytic cell markers. Thus, increased release of cytokines and IECs in black EH patients may impair EPC reparative capacity and aggravate vascular damage, and accelerate hypertension-related complications.

BACKGROUND Maintaining consistency of results over time is a challenge in laboratory medicine. Lot-to-lot reagent changes are a major threat to consistency of results. METHODS For the period October 2007 through July 2012, we reviewed lot validation data for each new lot of insulin-like growth factor 1 (IGF-1) reagents (Siemens Healthcare Diagnostics) at Mayo Clinic, Rochester, MN, and the University of Virginia, Charlottesville, VA. Analyses of discarded patient samples were used for comparison of lots. For the same period, we determined the distributions of reported patient results for each lot of reagents at the 2 institutions. RESULTS Lot-to-lot validation studies identified no reagent lot as significantly different from the preceding lot. By contrast, significant lot-to-lot changes were seen in the means and medians of 105 668 reported patient IGF-I results during the period. The frequency of increased results increased nearly 2-fold to a high of 17%, without detectable changes in the underlying patient demographics. Retrospective statistical analysis indicated that lot-to-lot comparison protocols were underpowered and that validation studies for this assay required testing &gt;100 samples to achieve 90% power to detect reagent lots that would significantly alter the distributions of patient results. CONCLUSIONS The number of test samples required for adequate lot-to-lot validation protocols is high and may be prohibitively large, especially for low-volume or complex assays. Monitoring of the distributions of patient results has the potential to detect lot-to-lot inconsistencies relatively quickly. We recommend that manufacturers implement remote monitoring of patient results from analyzers in multiple institutions to allow rapid identification of between-lot result inconsistency.

Abstract Lymphangioleiomyomatosis (LAM) and multifocal micronodular pneumocyte hyperplasia (MMPH) produce cystic and nodular disease, respectively, in the lungs of patients with tuberous sclerosis. The objective of this study was to prospectively characterize the prevalence, clinical presentation, and genetic basis of lung disease in TSC. We performed genotyping and computerized tomographic (CT) scanning of the chest on 23 asymptomatic women with tuberous sclerosis complex (TSC). Cystic pulmonary parenchymal changes consistent with LAM were found in nine patients (39%). These patients tended to be older than cyst-negative patients (31.9 ± 7.6 yr versus 24.8 ± 11.6 yr, p = 0.09). There was no correlation between presence of cysts and tobacco use, age at menarche, history of pregnancy, or estrogen-containing medications. Three of the cyst-positive patients had a prior history of pneumothorax. Pulmonary function studies revealed evidence of gas trapping but normal spirometric indices in the cyst-positive group. All nine cyst-positive patients had angiomyolipomas (AML), which were larger (p &lt; 0.05) and more frequently required intervention (p = 0.08) than cyst-negative patients (8 of 14 with AMLs, p &lt; 0.05). Ten patients (43%) had pulmonary parenchymal nodules. Pulmonary nodules were more common in women with cysts (78% versus 21%, p &lt; 0.05), and 52% of all patients had either cystic or nodular changes. TSC2 mutations were identified in all cyst-positive patients who were tested (n = 8), whereas both TSC1 and TSC2 mutations were found in patients with nodular disease. Correlation of the mutational and radiographic data revealed one pair of sisters who were discordant for cystic disease, two mother– daughter pairs who were discordant for nodular disease, and no clear association between cyst development and a specific mutational type. This prospective analysis demonstrates that cystic and nodular pulmonary changes consistent with LAM and MMPH are common in women with TSC.