Elevated lysosome-associated protein transmembrane-4β-35 is an independent prognostic marker in pancreatic carcinoma

OBJECTIVES

To investigate the relationship between lysosome-associated protein transmembrane-4β-35 (LAPTM4B-35) and the clinicopathological features and prognosis of pancreatic carcinoma.

METHODS

The level of LAPTM4B-35 protein was determined by semi quantitative immunohistochemistry in pancreatic carcinoma specimens. The relationship between LAPTM4B-35 level and prognosis was determined using univariate and multivariate analyses.

RESULTS

A total of 98 patient samples were included. The presence of LAPTM4B-35 protein was confirmed in 77/98 (78.6%) patients and was significantly associated with tumour stage, degree of differentiation and pathological staging of pancreatic carcinoma after primary surgery. Patients with high LAPTM4B-35 levels had a poorer overall survival compared with patients with lower levels. Multivariate analysis showed that LAPTM4B-35 was an independent prognostic factor for overall survival.

CONCLUSIONS

LAPTM4B-35 was found to be present at high levels in a large proportion of patients with pancreatic carcinoma, and was closely related to disease progression and poor prognosis. LAPTM4B-35 may represent a new molecular target for the clinical evaluation and treatment of pancreatic carcinoma.

Proteasome inhibitor bortezomib overcomes P-gp-mediated multidrug resistance in resistant leukemic cell lines

INTRODUCTION

To study the effect of bortezomib alone or in combination with daunorubicin (DNR) on an mdr1 single-factor drug-resistant leukemia cell line K562/MDR1, a multifactor-resistant cell line K562/A02, a drug-sensitive cell line K562, and primary cells from acute myeloid leukemia patients.

METHODS

The cell lines were exposed to bortezomib, DNR, and bortezomib plus DNR, and cell proliferation, cell cycle, apoptosis rate, and expression of MDR1/BCL2 were analyzed.

RESULTS

Bortezomib potently inhibited growth and increased the apoptosis rate in the cell lines. In K562/MDR1 and K562/A02, the calcium channel blocker verapamil reduced the 50% inhibitory concentration and apoptosis rate of DNR, a P-gp protein substrate, but not of bortezomib. Bortezomib plus DNR had synergistic effect on antiproliferation (synergistic ratio > 1). Apoptosis was substantially more increased by the combination of two drugs than by bortezomib alone. Bortezomib arrested the cell cycles of three cell lines at the G2/M stage, decreased BCL2 mRNA expression, but did not affect MDR1 mRNA levels. The antiproliferative role of bortezomib was also confirmed in primary leukemia cells.

CONCLUSION

Bortezomib is a promising potential therapy for acute leukemia, especially mdr1 drug-resistant leukemia.

An analysis of early insulin glargine added to metformin with or without sulfonylurea: impact on glycaemic control and hypoglycaemia

AIM

To evaluate the benefits of initiating insulin at an earlier versus later treatment stage, and regimens with/without sulfonylurea (SU).

METHODS

Pooled analysis of 11 prospective randomized clinical trials, including 2171 adults with uncontrolled type 2 diabetes initiating insulin glargine following a specific titration algorithm. Clinical outcomes were glycated haemoglobin A1c (HbA1c) reduction, per cent achieving HbA1c ≤ 7.0%, weight gain and hypoglycaemic events. Statistical analysis compared outcomes 24 weeks after basal insulin initiation in patients previously uncontrolled on 0/1 oral antidiabetic drug (OAD) versus 2 OADs, and in patients taking metformin (MET) or SU alone or in combination at baseline. A meta-analysis was also conducted.

RESULTS

For the pooled analysis, patients on 0/1 OAD and those on MET monotherapy at baseline had the largest 24-week reductions in HbA1c following the addition of insulin glargine (∼0.44 U/kg). Of patients failing MET/SU monotherapy and MET + SU in combination, 68.1, 50.4 and 56.4% achieved HbA1c ≤ 7.0%, respectively (p = 0.0006). Weight gain was lowest when basal insulin was added to MET. Patients on 0/1 OAD at baseline had significantly less symptomatic hypoglycaemia when basal insulin was added than those on 2 OADs (p = 0.0007). Despite higher insulin doses, those taking MET alone had less hypoglycaemia than those taking SU or MET + SU. Results were confirmed in the meta-analysis.

CONCLUSION

Adding insulin glargine to MET monotherapy early in treatment may provide efficacy/safety benefits over regimens including SU. This may reflect treatment earlier in the disease and supports the inclusion of insulin as a second step in the American Diabetes Association/European Association for the Study of Diabetes treatment algorithm.

Copy number imbalances between screen- and symptom-detected breast cancers and impact on disease-free survival

Screening mammography results in the increased detection of indolent tumors. We hypothesized that screen- and symptom-detected tumors would show genotypic differences as copy number imbalances (CNI) that, in part, explain differences in the clinical behavior between screen- and symptom-detected breast tumors. We evaluated 850 women aged 40 and above diagnosed with stage I and II breast cancer at the University of Texas MD Anderson Cancer Center between 1985 and 2000 with information available on method of tumor detection (screen vs. symptoms). CNIs in screen- and symptom-detected tumors were identified using high-density molecular inversion probe arrays. Cox proportional modeling was used to estimate the effect of method of tumor detection on disease-free survival after adjusting for age, stage, and the CNIs. The majority of tumors were symptom detected (n = 603) compared with screen detected (n = 247). Copy number gains in chromosomes 2p, 3q, 8q, 11p, and 20q were associated with method of breast cancer detection (P < 0.00001). We estimated that 32% and 63% of the survival advantage of screen detection was accounted for by age, stage, nuclear grade, and Ki67 in women aged 50 to 70 and aged 40 to 87, respectively. In each age category, an additional 20% of the survival advantage was accounted for by CNIs associated with method of detection. Specific CNIs differ between screen- and symptom-detected tumors and explain part of the survival advantage associated with screen-detected tumors. Measurement of tumor genotype has the potential to improve discrimination between indolent and aggressive screen-detected tumors and aids patient and physician decision making about use of surgical and adjuvant treatments.

Evidence for the adaptive evolution of ORF5 gene of Porcine reproductive and respiratory syndrome virus isolated in China

Porcine reproductive and respiratory syndrome virus (PRRSV) ORF5 gene encoding an envelope glycoprotein involved in humoral immunity is the most variable protein-coding gene of PRRSV. The present study aimed to identify potential selective pressures acting on the ORF5 gene of PRRSV isolates of North American type prevalent in China. The non-synonymous to synonymous rate ratio ω (dN/dS) was employed as a measure of selective pressure at the codon level. An overall ω of 0.45 indicated negative (purifying) selection as the major driving force operating on the ORF5 gene during adaptation of the virus to swine. Determination of ω values for individual amino acids sites revealed 8 positively selected sites, most of them situated in the N-terminal ectodomain, indicating their potential role in the binding of virus to the cellular receptors. Further, 75 negatively selected sites were identified in the rest of molecule, probably as a result of functional or immunological constraints. Determination of potential N-glycosylation sites revealed 7 sites, four of which coincided with the positively selected ones. These results indicated that a specific adaptive evolution has operated on the ORF5 gene of Chinese PRRSV isolates. It is hoped that the disclosed adaptive sites might help identify a candidate antigenic epitope for the use in vaccine against this serious swine disease.

On-line Planning and Scheduling: An Application to Controlling Modular Printers

We present a case study of artificial intelligence techniques applied to the control of production printing equipment. Like many other real-world applications, this complex domain requires high-speed autonomous decision-making and robust continual operation. To our knowledge, this work represents the first successful industrial application of embedded domain-independent temporal planning. Our system handles execution failures and multi-objective preferences. At its heart is an on-line algorithm that combines techniques from state-space planning and partial-order scheduling. We suggest that this general architecture may prove useful in other applications as more intelligent systems operate in continual, on-line settings. Our system has been used to drive several commercial prototypes and has enabled a new product architecture for our industrial partner. When compared with state-of-the-art off-line planners, our system is hundreds of times faster and often finds better plans. Our experience demonstrates that domain-independent AI planning based on heuristic search can flexibly handle time, resources, replanning, and multiple objectives in a high-speed practical application without requiring hand-coded control knowledge.

Best-First Heuristic Search for Multicore Machines

To harness modern multicore processors, it is imperative to develop parallel versions of fundamental algorithms. In this paper, we compare different approaches to parallel best-first search in a shared-memory setting. We present a new method, PBNF, that uses abstraction to partition the state space and to detect duplicate states without requiring frequent locking. PBNF allows speculative expansions when necessary to keep threads busy. We identify and fix potential livelock conditions in our approach, proving its correctness using temporal logic. Our approach is general, allowing it to extend easily to suboptimal and anytime heuristic search. In an empirical comparison on STRIPS planning, grid pathfinding, and sliding tile puzzle problems using 8-core machines, we show that A*, weighted A* and Anytime weighted A* implemented using PBNF yield faster search than improved versions of previous parallel search proposals.

η and η' mesons from lattice QCD

The large mass of the ninth pseudoscalar meson, the η', is believed to arise from the combined effects of the axial anomaly and the gauge field topology present in QCD. We report a realistic, 2+1-flavor, lattice QCD calculation of the η and η' masses and mixing which confirms this picture. The physical eigenstates show small octet-singlet mixing with a mixing angle of θ=-14.1(2.8)°. Extrapolation to the physical light quark mass gives, with statistical errors only, mη=573(6) MeV and mη'=947(142) MeV, consistent with the experimental values of 548 and 958 MeV.

Selection pressure on the hemagglutinin gene of influenza A (H1N1) virus: adaptation to human and swine hosts in Asia

Influenza A (H1N1) virus is an important pathogen that can be transmitted in the enzootic cycle involved in influenza epidemics. In this study, we analyzed natural selection on the 260 sequences of subtype 1 hemagglutinin (HA1) gene of H1N1 viruses isolated from humans and swine in Asia. Nonsynonymous and synonymous substitution rates (dN, dS) were determined for each amino acid site in the HA1 coding region. Four and two positively selected sites were identified in human and swine viruses, respectively. These sites might be involved in the change of antigenic epitopes to evade the host immune system. The results indicate that more diversifying and less purifying selection controls HA1 of human viruses compared with the swine viruses. Furthermore, thirteen sites evolving differently in human and swine viruses were identified in the HA1. These sites may play a role in the cross-species transmission. The analysis of adaptive evolution of the HA1 can provide valuable information for accelerating vaccine and drug development for prevention and treatment of influenza A (H1N1) in Asia.

KEYWORDS

Influenza A virus; H1N1; hemagglutinin; positive selection; antigenic epitope.

Prenatal ethanol exposure attenuates GABAergic inhibition in basolateral amygdala leading to neuronal hyperexcitability and anxiety-like behavior of adult rat offspring

Prenatal exposure to a relatively high-dose ethanol (EtOH) caused anxiety-like behavior of adult male rat offspring. Previous studies have demonstrated that GABA system in the basolateral amygdala complex (BLA) is involved in the pathogensis of anxiety-related disorders. The role of GABAergic system in the BLA was investigated in anxiety-like behavior evoked by prenatal EtOH exposure. The infusion of midazolam (MDZ), a positive modulator of GABA(A) receptor, into the BLA prevented anxiety-like behavior in EtOH-offspring without affecting the corresponding behavior of control offspring. The data suggest that anxiety-like behavior could be causally related to increased neuronal excitability attributable to depressed GABAergic inhibition in the BLA. To test this hypothesis, evoked potential was studied using brain slices from EtOH-offspring. Potential evoked in the BLA by single stimuli applied to external capsule showed multispike responses, indicative of GABAergic disinhibition. These multiple responses were no longer evident after the perfusion with MDZ. In the slices from EtOH-offspring, paired-pulse inhibition (GABA(A)-dependent) was suppressed. Also, in EtOH-offspring, long-term potentiation (LTP) was induced by a single train of high frequency stimulation, which did not induce LTP in control rats. Moreover, MDZ pretreatment prevented the facilitating effect of EtOH on LTP induction. The data provide the functional evidence that prenatal EtOH exposure attenuates GABAergic inhibition in the BLA resulting in neuronal hyperexcitability and anxiety-like behavior of adult rat offspring.