"Very early" intrahepatic cholangiocarcinoma in cirrhotic patients: should liver transplantation be reconsidered in these patients?

A retrospective cohort multicenter study was conducted to analyze the risk factors for tumor recurrence after liver transplantation (LT) in cirrhotic patients found to have an intrahepatic cholangiocarcinoma (iCCA) on pathology examination. We also aimed to ascertain whether there existed a subgroup of patients with single tumors ≤2 cm ("very early") in which results after LT can be acceptable. Twenty-nine patients comprised the study group, eight of whom had a "very early" iCCA (four of them incidentals). The risk of tumor recurrence was significantly associated with larger tumor size as well as larger tumor volume, microscopic vascular invasion and poor degree of differentiation. None of the patients in the "very early" iCCA subgroup presented tumor recurrence compared to 36.4% of those with single tumors >2 cm or multinodular tumors, p = 0.02. The 1-, 3- and 5-year actuarial survival of those in the "very early" iCCA subgroup was 100%, 73% and 73%, respectively. The present is the first multicenter attempt to ascertain the risk factors for tumor recurrence in cirrhotic patients found to have an iCCA on pathology examination. Cirrhotic patients with iCCA ≤2 cm achieved excellent 5-year survival, and validation of these findings by other groups may change the current exclusion of such patients from transplant programs.

Axonal mitochondrial clusters containing mutant SOD1 in transgenic models of ALS

We studied the subcellular distribution of mitochondria and superoxide dismutase-1 (SOD1) in whole mounts of microdissected motor axons of rats expressing the ALS-linked SOD1-G93A mutation. The rationale was to determine whether physical interactions between the enzyme and mitochondria were linked to the axonopathy of motor fibers occurring in amyotrophic lateral sclerosis (ALS). Mitochondria and SOD1 displayed a homogeneous distribution along motor axons both in nontransgenic rats and in those overexpressing wild-type SOD1. In contrast, axons from SOD1-G93A rats (older than 35 days) showed accumulation of mitochondria in discrete clusters located at regular intervals. Most of SOD1 immunoreactivity was enriched in these clusters and colocalized with mitochondria, suggesting a recruitment of SOD1-G93A to the organelle. The SOD1/mitochondrial clusters were abundant in motor axons but scarcely seen in sensory axons. Clusters also were stained for neuronal nitric oxide synthase, nitrotyrosine, and cytochrome c. The later also was detected surrounding clusters. Ubiquitin colocalized with clusters only at late stages of the disease. The cytoskeleton was not overtly altered in clusters. These results suggest that mutant SOD1 and defective mitochondria create localized dysfunctional domains in motor axons, which may lead to progressive axonopathy in ALS.

Wavelet transform analysis of heart rate variability during myocardial ischaemia

Analysis of heart rate variability (HRV) is a valuable, non-invasive method for quantifying autonomic cardiac control in humans. Frequency-domain analysis of HRV involving myocardial ischaemic episodes should take into account its non-stationary behaviour. The wavelet transform is an alternative tool for the analysis of non-stationary signals. Fourteen patients have been analysed, ranging from 40 to 64 years old and selected from the European Electrocardiographic ST-T Database (ESDB). These records contain 33 ST episodes, according to the notation of the ESDB, with durations of between 40s and 12 min. A method for analysing HRV signals using the wavelet transform was applied to obtain a time-scale representation for very low-frequency (VLF), low-frequency (LF) and high-frequency (HF) bands using the orthogonal multiresolution pyramidal algorithm. The design and implementation using fast algorithms included a specially adapted decomposition quadrature mirror filter bank for the frequency bands of interest. Comparing a normality zone against the ischaemic episode in the same record, increases in LF (0.0112 +/- 0.0101 against 0.0175 +/- 0.0208 s2 Hz(-1); p<0.1) and HF (0.0011 +/- 0.0008 against 0.00 17 +/- 0.0020 s2 Hz(-1); p<0.05) were obtained. The possibility of using these indexes to develop an ischaemic-episode classifier was also tested. Results suggest that wavelet analysis provides useful information for the assessment of dynamic changes and patterns of HRV during myocardial ischaemia.

Speciation and paraphyly in western Mediterranean hares (Lepus castroviejoi, L. europaeus, L. granatensis, and L. capensis) revealed by mitochondrial DNA phylogeny

Mitochondrial DNA (mtDNA) variation among specimens of the northwestern African hare (Lepus capensis schlumbergeri) and three European hares sampled in Spain (L. castroviejoi and L. granatensis, which are endemic to the Iberian Peninsula, and L. europaeus) was analyzed using seven restriction endonucleases. Fourteen haplotypes were found among the 34 animals examined. Restriction site maps were constructed and the phylogeny of the haplotypes was inferred. mtDNA of L. capensis was the most divergent, which is consistent with its allopatric African distribution and with an African origin of European hares. We estimated that mtDNA in hares diverges at a rate of 1.5-1.8% per MY assuming that the European and African populations separated 5-6 MYBP. Maximum intraspecies nucleotides divergences were 1.3% in L. capensis, 2.7% in L. castroviejoi, and 2.3% in L. granatensis but 13.0% in L. europaeus. The latter species contained two main mtDNA lineages, one on the branch leading to L. castroviejoi and the other on that leading to L. granatensis. The separation of these two lineages from the L. castroviejoi or L. granatensis lineages appears to be much older than the first paleontological record of L. europaeus in the Iberian peninsula. This suggests that the apparent polyphyly of L. europaeus is due not to secondary introgression, but to the retention of ancestral polymorphism in L. europaeus. The results suggest that L. europaeus either has evolved as a very large population for a long time or has been fractionated. Such a pattern of persistence of very divergent lineages has also been reported in other species of highly mobile terrestrial mammals. As far as mtDNA is concerned. L. europaeus appears to be the common phylogenetic trunk which has diversified during dispersion over the European continent and from which L. castroviejoi and L. granatensis speciated separately in southwest Europe.

SUTIL: intelligent ischemia monitoring system

SUTIL is an intelligent monitoring system for intensive and exhaustive follow up of patients in coronary care units. This system processes electrocardiographic and hemodynamic signals in real time, with the main objective of detecting ischemic episodes. In this paper, we describe the tasks included in SUTIL. In addition to basic tasks, those at higher levels will also be presented. Some of these latter tasks attempt to mimic, to some extent, the way in which the human expert operates.

Solving the pooling problem using generalized reduced gradient and successive linear programming algorithms

In earlier issues of this bulletin, Haverly and Hart discussed solving some simple pooling problems using LP recursion [1]-[3]. We thought it would be interesting to attempt to solve these problems using some nonlinear programming (NLP) codes. This note briefly discusses the codes and algorithms used, presents the results, and discusses some properties of the models.

Musashi 2 influences chronic lymphocytic leukemia cell survival and growth making it a potential therapeutic target

Progression of chronic lymphocytic leukemia (CLL) results from the expansion of a small fraction of proliferating leukemic B cells. When comparing the global gene expression of recently divided CLL cells with that of previously divided cells, we found higher levels of genes involved in regulating gene expression. One of these was the oncogene Musashi 2 (MSI2), an RNA-binding protein that induces or represses translation. While there is an established role for MSI2 in normal and malignant stem cells, much less is known about its expression and role in CLL. Here we report for the first time ex vivo and in vitro experiments that MSI2 protein levels are higher in dividing and recently divided leukemic cells and that downregulating MSI2 expression or blocking its function eliminates primary human and murine CLL and mature myeloid cells. Notably, mature T cells and hematopoietic stem and progenitor cells are not affected. We also confirm that higher MSI2 levels correlate with poor outcome markers, shorter time-to-first-treatment, and overall survival. Thus, our data highlight an important role for MSI2 in CLL-cell survival and proliferation and associate MSI2 with poor prognosis in CLL patients. Collectively, these findings pinpoint MSI2 as a potentially valuable therapeutic target in CLL.

Fuzzy logic in a patient supervision system

A patient supervision system in progress for intensive and coronary care units, focused on patients with acute myocardial infarct is briefly described particularly regarding the role that fuzzy logic is playing in its design, and why this is so.

Methylation status regulates lipoprotein lipase expression in chronic lymphocytic leukemia

Among different prognostic factors in chronic lymphocytic leukemia (CLL), we previously demonstrated that lipoprotein lipase (LPL) is associated with an unmutated immunoglobulin profile and clinical poor outcome. Despite the usefulness of LPL for CLL prognosis, its functional role and the molecular mechanism regulating its expression are still open questions. Interaction of CLL B-cells with the tissue microenvironment favors disease progression by promoting malignant B-cell growth. Since tissue methylation can be altered by environmental factors, we investigated the methylation status of the LPL gene and the possibility that overexpression could be associated with microenvironment signals. Our results show that a demethylated state of the LPL gene is responsible for its anomalous expression in unmutated CLL cases and that this expression is dependent on microenvironment signals. Overall, this work proposes that an epigenetic mechanism, triggered by the microenvironment, regulates LPL expression in CLL disease.

Randomized comparison of efficacy of cooled tip catheter ablation of atrial flutter: anatomic versus electrophysiological complete isthmus block

There is a subset of patients with failed ablation of the cavotricuspid isthmus (CTI) using standard catheters and with 10% of the patients having recurrences. The purpose of this study was to compare the cooled and standard ablation with regard to acute successful electrophysiological achievement of bidirectional isthmus block and the subacute anatomic characteristics of the lesions. This randomized, experimental study compares the effects of ablation on the isthmus using a cooled catheter with those of a standard ablation catheter in 16 pigs. In 12 animals, CTI block was achieved after ablation (8/8 cooled and 4/8 standard). In two animals, it was not possible to achieve complete isthmus block and two had persistent slow conduction (all four using the standard catheter). After 1 week, the animals were slaughtered. The size of the lesion was greater with the irrigated tip catheters. Transmural lesions were found in 14 animals. A complete line of anatomic isthmus block was not documented after thefirst line in six animals, four with the standard and two with the cooled catheter. A conduction block was never present across gaps > or = 5 mm. In conclusion cooled catheters achieved a complete line of electrophysiological and anatomical block in a significantly higher percentage than the standard catheters.

Dissecting chronic lymphocytic leukemia microenvironment signals in patients with unmutated disease: microRNA-22 regulates phosphatase and tensin homolog/AKT/FOXO1 pathway in proliferative leukemic cells

Chronic lymphocytic leukemia (CLL) is characterized by the accumulation of clonal B cells arrested in G0/G1 stages that coexist with proliferative B cells. We identified one of these proliferative subsets in the peripheral blood from patients with unmutated disease (UM). Aiming to characterize the molecular mechanism underlying this proliferative behavior, we performed gene expression analysis of the mRNA and microRNAs in this leukemic subpopulation and compared results with those for the quiescent counterpart. Our results suggest that proliferation of this subset mainly depends on microRNA-22 overexpression, which induces phosphatase and tensin homolog (PTEN) down-regulation and phosphoinositide 3-kinase (PI3K)/AKT pathway activation. These results underline the role of the PI3K/AKT pathway at the origin of this proliferative pool in patients with UM CLL and provide additional rationale for the use of PI3K inhibitors.

AID overexpression leads to aggressive murine CLL and nonimmunoglobulin mutations that mirror human neoplasms

Most cancers become more dangerous by the outgrowth of malignant subclones with additional DNA mutations that favor proliferation or survival. Using chronic lymphocytic leukemia (CLL), a disease that exemplifies this process and is a model for neoplasms in general, we created transgenic mice overexpressing the enzyme activation-induced deaminase (AID), which has a normal function of inducing DNA mutations in B lymphocytes. AID not only allows normal B lymphocytes to develop more effective immunoglobulin-mediated immunity, but is also able to mutate nonimmunoglobulin genes, predisposing to cancer. In CLL, AID expression correlates with poor prognosis, suggesting a role for this enzyme in disease progression. Nevertheless, direct experimental evidence identifying the specific genes that are mutated by AID and indicating that those genes are associated with disease progression is not available. To address this point, we overexpressed Aicda in a murine model of CLL (Eμ-TCL1). Analyses of TCL1/AID mice demonstrate a role for AID in disease kinetics, CLL cell proliferation, and the development of cancer-related target mutations with canonical AID signatures in nonimmunoglobulin genes. Notably, our mouse models can accumulate mutations in the same genes that are mutated in human cancers. Moreover, some of these mutations occur at homologous positions, leading to identical or chemically similar amino acid substitutions as in human CLL and lymphoma. Together, these findings support a direct link between aberrant AID activity and CLL driver mutations that are then selected for their oncogenic effects, whereby AID promotes aggressiveness in CLL and other B-cell neoplasms.

[Macroscopic and microscopic study of the right coronary artery after radiofrequency catheter ablation of cavotricuspid isthmus in an experimental model]

INTRODUCTION AND OBJECTIVES

The right coronary artery (RCA) is found in the AV groove, just below the ablation target of atrial flutter, the cavotricuspid isthmus (ICT). After radiofrequency (RF) ablation with standard catheters, there have been no reports of complications, but it may not be successful in 10% of the cases. However, the use of irrigated tip catheters, which create deeper lesions, might potentially damage the coronary tree.

METHODS

We analyzed the effects of ICT RF ablation on the coronary tree, with macroscopic and microscopic anatomopathological study. Ablation on ICT was performed using an irrigated tip catheter in 16 pigs and was randomly compared with a standard ablation catheter. There were no clinical problems, modifications of ST or new arrhythmias during the ablation. The heart was extracted at 1 week.

RESULTS

The macroscopic study demonstrated that the right coronary artery was preserved, along the ICT, surrounded by the epicardial fat. The microscopic study showed an inflammatory reaction in the epicardial fat that reached the adventitia of the coronary artery, but never produced necrosis in 14 cases. The muscular wall of the artery had signs of focal inflammation without endothelium involvement in 2 cases. However, we found a subepicardial vein completely damaged by the radiofrequency.

CONCLUSIONS

Although the right coronary artery is located just below the isthmus, no necrosis was observed in any case. However, there was an inflammatory reaction that focally reached the muscular wall. The veins may be damaged in RF ablation, perhaps due to the different blood flow of each vessel.

Chronic lymphocytic leukemia-like monoclonal B-cell lymphocytosis exhibits an increased inflammatory signature that is reduced in early-stage chronic lymphocytic leukemia

Several studies in chronic lymphocytic leukemia (CLL) patients have reported impaired immune cell functions, which contribute to tumor evasion and disease progression. However, studies on CLL-like monoclonal B-cell lymphocytosis (MBL) are scarce. In the study described here, we characterized the immune environment in 62 individuals with clinical MBL, 56 patients with early-stage CLL, and 31 healthy controls. Gene expression arrays and quantitative reverse transcription polymerase chain reaction were performed on RNA from CD4⁺ peripheral blood cells; serum cytokines were measured with immunoassays; and HLA-DR expression on circulating monocytes, as well as the percentages of Th1, cytotoxic, exhausted, and effector CD4⁺ T cells, were evaluated by flow cytometry. In addition, cell cultures of clonal B cells and CD14-enriched or -depleted cell fractions were performed. Strikingly, MBL and early-stage CLL differed in pro-inflammatory signatures. An increased inflammatory drive orchestrated mainly by monocytes was identified in MBL, which exhibited enhanced phagocytosis, pattern recognition receptors, interleukin-8 (IL8), HMGB1, and acute response signaling pathways and increased pro-inflammatory cytokines (in particular IL8, interferon γ [IFNγ], and tumor necrosis factor α). This inflammatory signature was diminished in early-stage CLL (reduced IL8 and IFNγ levels, IL8 signaling pathway, and monocytic HLA-DR expression compared with MBL), especially in those patients with mutations in IGHV genes. Additionally, CD4⁺ T cells of MBL and early-stage CLL exhibited a similar upregulation of Th1 and cytotoxic genes and expanded CXCR3⁺ and perforin⁺ CD4⁺ T cells, as well as PD1⁺ CD4⁺ T cells, compared with controls. Cell culture assays disclosed tumor-supporting effects of monocytes similarly observed in MBL and early-stage CLL. These novel findings reveal differences in the inflammatory environment between MBL and CLL, highlighting an active role for antigen stimulation in the very early stages of the disease, potentially related to malignant B-cell transformation.