Citations

Abstract Waldenström macroglobulinemia (WM) is a distinct B-cell lymphoproliferative disorder for which clearly defined criteria for the diagnosis, initiation of therapy, and treatment strategy have been proposed as part of the consensus panels of International Workshops on WM (IWWM). As part of the IWWM-7 and based on recently published and ongoing clinical trials, the panels updated treatment recommendations. Therapeutic strategy in WM should be based on individual patient and disease characteristics (age, comorbidities, need for rapid disease control, candidacy for autologous transplantation, cytopenias, IgM-related complications, hyperviscosity, and neuropathy). Mature data show that rituximab combinations with cyclophosphamide/dexamethasone, bendamustine, or bortezomib/dexamethasone provided durable responses and are indicated for most patients. New monoclonal antibodies (ofatumumab), second-generation proteasome inhibitors (carfilzomib), mammalian target of rapamycin inhibitors, and Bruton's tyrosine kinase inhibitors are promising and may expand future treatment options. A different regimen is typically recommended for relapsed or refractory disease. In selected patients with relapsed disease after long-lasting remission, reuse of a prior effective regimen may be appropriate. Autologous stem cell transplantation may be considered in young patients with chemosensitive disease and in newly diagnosed patients with very-high-risk features. Active enrollment of patients with WM in clinical trials is encouraged.

Proposed kinetic mechanism for Mt IMPDH in the presence of K + .

ABSTRACTBackground and ObjectiveThe aims of the present study were to investigate the thermal‐dose dependent effect of heat stress on hepatocyte and HCC cell death mechanisms using clinically relevant experimental heat stress conditions in vitro and to investigate apoptotic cell death induced by laser thermal ablation in vivo.Study Design/Materials and MethodsInstitutional Animal Care and Use Committee approved all studies. Hepatocyte and HCC cell lines were heat stressed from 37 to 60°C for 2 or 10 minutes and assessed for viability, cytotoxicity and caspase‐3/7 activity at 6 and/or 24 hours post‐treatment (N = 3). Viability experiments were repeated with the RIPK1 inhibitor Necrostatin‐1 to block necroptosis (N = 3). Rats with orthotopic HCC tumors stably expressing luciferase (N1S1luc2) were randomized to US‐guided laser ablation (3W‐45s for an intentional partial ablation; N = 6) or sham (N = 6) and followed by post‐ablation caspase‐3/7 bioluminescence imaging at 6 and 24 hours and cleaved caspase‐3 immunostaining. P < 0.05 was considered statistically significant.ResultsHeat‐stress induced apoptosis and necrosis in hepatocytes and HCC cells in a thermal dose and cell‐type dependent manner. Inhibition of RIPIK1‐mediated necroptosis induced a significant, differential increase in HCC cell viability under physiologic and hyperthermic heat stress (P < 0.001). Intentional partial laser thermal ablation induced a significant increase in caspase‐3/7 activity in the laser versus sham ablation groups at both 6 hours (10.1‐fold, P < 0.01) and 24 hours (16.7‐fold, P < 0.02). Immunohistochemistry confirmed increased cleaved caspase‐3 staining at the tumor ablation margin 24 hours post‐ablation.ConclusionsBoth regulated and non‐regulated cell death mechanisms mediate heat stress‐induced HCC cell killing and vary between hepatocytes and HCC subtypes. Apoptosis is a significant mechanism of cell death at the HCC tumor ablation margin. Lasers Surg. Med. 46:290–301, 2014. © 2014 Wiley Periodicals, Inc.

BackgroundHenoch‐Schönlein purpura (HSP) is a vasculitis that can affect the skin and kidneys. It is characterized by immunoglobulin (Ig) A‐predominant deposition in small blood vessels. To our knowledge, there has been no comparison of direct immunofluorescence (DIF) findings in skin and kidney biopsy specimens.MethodsWe retrospectively studied 21 adults with HSP who had IgA deposition in the skin and kidneys. The skin and kidney DIF findings were compared and tested for an association with the progression of renal disease.ResultsMean age of the patients was 51.4 years. Follow‐up data were available for 19 patients, of whom 5 had progression to chronic kidney disease or renal failure. Concordance between DIF findings on skin and renal biopsies was 100% for IgA, 80% for C3, 80% for IgG, 71% for IgM and 53% for fibrinogen. A worse renal outcome was associated with renal IgG deposition (p = 0.04). A trend for worse renal outcome was found with renal fibrinogen and skin IgM deposition (p = 0.10 and 0.14, respectively).ConclusionsIn this retrospective study of adult HSP, the concordance between DIF findings in skin and kidney specimens was low‐moderate. Further study is required to elucidate the mechanisms responsible for these differences in Ig deposition.

Activation of the renin-angiotensin-aldosterone system plays a critical role in the development of chronic renal damage in patients with renovascular hypertension. Although angiotensin II (Ang II) promotes oxidative stress, inflammation, and fibrosis, it is not known how these pathways intersect to produce chronic renal damage. We tested the hypothesis that renal parenchymal cells are subjected to oxidant stress early in the development of RVH and produce signals that promote influx of inflammatory cells, which may then propagate chronic renal injury. We established a reproducible murine model of RVH by placing a tetrafluoroethhylene cuff on the right renal artery. Three days after cuff placement, renal tissue demonstrates no histologic abnormalities despite up regulation of both pro- and anti-oxidant genes. Mild renal atrophy was observed after seven days and was associated with induction of Tnfα and influx of CD3+ T cells and F4/80+ macrophages. By 28 days, kidneys developed severe renal atrophy with interstitial inflammation and fibrosis, despite normalization of plasma renin activity. Based on these considerations, we propose that renal parenchymal cells initiate a progressive cascade of events leading to oxidative stress, interstitial inflammation, renal fibrosis, and atrophy.

Purpose To determine the rates of neurologic adverse events following Pipeline Embolic Device (PED) placement for intracranial aneurysm treatment. Methods A retrospective review of medical records was performed at 19 centres to identify consecutive intracranial aneurysms treated with the PED following regulatory approval for marketing the device in the given country. All patients in whom at least one PED was placed and in whom follow-up was available prior to IRB or ethics panel approval were enrolled. Three anatomic/size subgroups were defined, including 1) pre-PComm, internal carotid artery aneurysms 10mm or greater (“large ICA”), 2) ICA aneurysms >10mm and/or at/distal to the PComm region (“other anterior circulation”), and 3) posterior circulation aneurysms. “Primary safety events” included stroke, haemorrhage, parent artery stenosis, permanent cranial neuropathy, and spontaneous rupture of the target aneurysm. Severe safety events were defined as any event causing significant impairment of functioning causing the inability of the subject to carry out usual activities. Statistical analysis was performed using standard summary statistics; p-values comparing subgroups were computed using Pearson's chi-square test for discrete variables and analysis of variance for continuous variables. Results To date, 580 aneurysms, including 183 large ICA, 344 other anterior circulation, and 53 posterior circulation aneurysms have been treated and followed for a mean duration of 7.8 months (SD 7.3, range 0.1 - 40.8). 437 (76%) of 580 aneurysms were saccular and 80 (14%) were fusiform; 32 (5.5%) were classified as giant (<25mm diameter). 549 (93%) were unruptured. 241 (42%) were treated with multiple PEDs. Primary safety events were noted in 62 (12%) cases. Severe neurological events occurred in 35 (6.8%) cases, and occurred more frequently in posterior circulation aneurysms (7 (13%)) than in either large ICA or other anterior circulation aneurysms (15 (8.8%) and (13 (4.5%), respectively, p=.035). Major stroke occurred in 20 (3.9%) of 515 subjects (4.1%, 3.1%, and 7.5% in large ICA, other anterior circulation, and posterior circulation aneurysms, respectively, p=.31). Ipsilateral intracranial haemorrhage occurred in 12 (2.3%) subjects (3.5%, 1.7%, and 1.9% in large ICA, other anterior circulation, and posterior circulation aneurysms, respectively, p=.47). Spontaneous aneurysm rupture occurred in 3 (0.6%) aneurysms, all of which were giant, resulting in a 9% incidence of rupture in giant aneurysms. Mortality rate was 4.3% and was significantly higher for posterior circulation aneurysms (11.3%) as compared to anterior circulation aneurysms (3.5%, p=.019). Conclusions Preliminary data indicates that in approximately 7% of aneurysms treated with PED, substantial neurologic complications occurred, with rates of both severe neurologic events and mortality occurring significantly higher in the posterior as compared to the anterior circulation. Both ipsilateral haemorrhage and spontaneous aneurysm rupture were rare, with the latter event limited to giant aneurysms. Disclosures D. Kallmes: 1; C; MicroVention, Sequent, Benvenue, eV3. 2; C; General Electric, Codman, eV3. E. Boccardi: None. A. Bonafe: None. S. Cekirge: None. D. Fiorella: 2; C; Pipeline proctor, consultant, (<10K, EV3). R. Hanel: None. P. Jabbour: None. E. Levy: None. D. Lopes: 6; C; Receives compensation for training & proctoring for Pipeline devices. P. Lylyk: None. C. McDougall: None. A. Siddiqui: None. I. Szikora: None. H. Woo: None.

Heme oxygenase-2 (HO-2), the constitutive isoform of the heme-degrading enzyme heme oxygenase, may serve as an anti-inflammatory vasorelaxant, in part, by generating carbon monoxide. Arteriovenous fistulas (AVFs) are employed as hemodialysis vascular accesses because they provide an accessible, high-blood-flow vascular segment. We examined the role of vascular expression of HO-2 in AVF function. An AVF was created in mice by anastomosing the carotid artery to the jugular vein. HO-2 expression was detected by immunohistochemistry in the intact carotid artery, mainly in endothelial cells and smooth muscle cells; expression of HO-2 protein and mRNA was modestly increased in the artery of the AVF. Creating an AVF in HO-2−/−mice compared with an AVF in HO-2+/+mice led to markedly reduced AVF blood flow and increased numbers of nonfunctioning AVFs. The impairment of AVF function in the setting of HO-2 deficiency could not be ascribed to either preexisting intrinsic abnormalities in endothelium-dependent and endothelium-independent relaxation of the carotid artery in HO-2-deficient mice or to impaired vasorelaxant responses in the intact carotid artery in vivo. HO-1 mRNA was comparably induced in the AVF in HO-2+/+and HO-2−/−mice, whereas the AVF in HO-2−/−mice compared with that in HO-2+/+mice exhibited exaggerated induction of matrix metalloproteinase (MMP)-9 but similar induction of MMP-2. HO-2 deficiency also led to lower AVF blood flow when AVFs were created in uremia, the latter induced by subtotal nephrectomy. We conclude that HO-2 critically contributes to the adequacy of AVF blood flow and function.