Oral cladribine for B-cell chronic lymphocytic leukaemia: report of a phase II trial with a 3-d, 3-weekly schedule in untreated and pretreated patients, and a long-term follow-up of 126 previously untreated patients

A phase II study was undertaken to evaluate the efficacy and toxicity of a new schedule of cladribine administration (10 mg/m2 orally daily for 3 d every 3 weeks) in 107 patients with B-cell chronic lymphocytic leukaemia (CLL). To minimize toxicity, treatment withdrawal criteria were defined. The results of the 63 previously untreated patients were retrospectively compared with 63 from an earlier study using a 5-d monthly schedule. The compiled data were analysed for prognostic factors for survival. No significant difference regarding response were seen in the two cohorts of the 126 previously untreated patients. The complete response (CR), nodular partial response (nPR) and partial response (PR) rates were 15%, 21% and 41%. Quality of response had no impact on survival. The 3- and 5-year overall survival for previously untreated patients was 73% and 58%, respectively, with a median follow-up of 54 months. Pretreatment haemoglobin <11.0 g/dl and elevated beta-2-microglobulin had a negative influence on survival. Major infections occurred in 21% of patients in the 3-d study compared with 35% in the 5-d study. The overall response (OR) and CR rates in the 40 previously treated patients were 34% and 5% respectively. Median overall survival was 24 months and median progression-free survival for responding patients was 14 months. Cladribine used as a single agent is an effective treatment with an acceptable safety profile for pretreated and untreated B-CLL. The achievement of complete remission was not a prerequisite for long-term survival.     

Biphasic intra-thoracic pressure regulation augments cardiac index during porcine peritonitis: a feasibility study

Preservation of cardiac output (CO) and pulmonary artery pressure (PAP) is vital to maintaining tissue oxygenation in sepsis. This feasibility study tested the hypothesis that therapeutic intra-thoracic pressure regulation (tIPR), delivered with a novel device, was designed to non-invasively enhance venous return by creating sub-atmospheric intra-thoracic pressure during the expiratory phase of mechanical ventilation, improves CO without fluid resuscitation in a porcine E. coli peritonitis model of sepsis. Seven pigs were intubated, anaesthetized and instrumented with a Swan-Ganz and femoral artery catheter. After a 30?min basal period, a fibrin clot containing 4–5?×?10⁹ cfu kg^?1 E. coli O111.B4 was implanted in the peritoneum. One hour after clot implantation, tIPR was utilized for 30?min and then removed from the ventilator circuit for 30?min. This tIPR cycle was repeated 4-times. Changes in haemodynamic parameters were calculated by comparing pre-tIPR values to peak values during tIPR administration. Following peritonitis, tIPR significantly increased the peak cardiac index (mean?±?SEM) (14.8?±?2.6 vs 7.9?±?2.3?ml kg^?1) and mean arterial pressure (10.2?±?1.5 vs 4.9?±?1.1?mmHg) and simultaneously decreased PAP (?7.7?±?1.5 vs ?2.7?±?0.8?mmHg). These results support the feasibility of the concept that therapeutic application of negative expiratory pressure may provide a non-invasive and complementary approach to increase cardiac output and organ perfusion in the setting of septic shock.     

A systematic review of cancer GWAS and candidate gene meta-analyses reveals limited overlap but similar effect sizes

Candidate gene and genome-wide association studies (GWAS) represent two complementary approaches to uncovering genetic contributions to common diseases. We systematically reviewed the contributions of these approaches to our knowledge of genetic associations with cancer risk by analyzing the data in the Cancer Genome-wide Association and Meta Analyses database (Cancer GAMAdb). The database catalogs studies published since January 1, 2000, by study and cancer type. In all, we found that meta-analyses and pooled analyses of candidate genes reported 349 statistically significant associations and GWAS reported 269, for a total of 577 unique associations. Only 41 (7.1%) associations were reported in both candidate gene meta-analyses and GWAS, usually with similar effect sizes. When considering only noteworthy associations (defined as those with false-positive report probabilities ≤0.2) and accounting for indirect overlap, we found 202 associations, with 27 of those appearing in both meta-analyses and GWAS. Our findings suggest that meta-analyses of well-conducted candidate gene studies may continue to add to our understanding of the genetic associations in the post-GWAS era.     

Protective immunity against respiratory tract challenge with Yersinia pestis in mice immunized with an adenovirus-based vaccine vector expressing V antigen

The aerosol form of the bacterium Yersinia pestis causes the pneumonic plague, a rapidly fatal disease. At present, no plague vaccines are available for use in the United States. One candidate for the development of a subunit vaccine is the Y. pestis virulence (V) antigen, a protein that mediates the function of the Yersinia outer protein virulence factors and suppresses inflammatory responses in the host. On the basis of the knowledge that adenovirus (Ad) gene-transfer vectors act as adjuvants in eliciting host immunity against the transgene they carry, we tested the hypothesis that a single administration of a replication-defective Ad gene-transfer vector encoding the Y. pestis V antigen (AdsecV) could stimulate strong protective immune responses without a requirement for repeat administration. AdsecV elicited specific T cell responses and high IgG titers in serum within 2 weeks after a single intramuscular immunization. Importantly, the mice were protected from a lethal intranasal challenge of Y. pestis CO92 from 4 weeks up to 6 months after immunization with a single intramuscular dose of AdsecV. These observations suggest that an Ad gene-transfer vector expressing V antigen is a candidate for development of an effective anti-plague vaccine.     

Detecting polymorphic regions in Arabidopsis thaliana with resequencing microarrays

Whole-genome oligonucleotide resequencing arrays have allowed the comprehensive discovery of single nucleotide polymorphisms (SNPs) in eukaryotic genomes of moderate to large size. With this technology, the detection rate for isolated SNPs is typically high. However, it is greatly reduced when other polymorphisms are located near a SNP as multiple mismatches inhibit hybridization to arrayed oligonucleotides. Contiguous tracts of suppressed hybridization therefore typify polymorphic regions (PRs) such as clusters of SNPs or deletions. We developed a machine learning method, designated margin-based prediction of polymorphic regions (mPPR), to predict PRs from resequencing array data. Conceptually similar to hidden Markov models, the method is trained with discriminative learning techniques related to support vector machines, and accurately identifies even very short polymorphic tracts (<10 bp). We applied this method to resequencing array data previously generated for the euchromatic genomes of 20 strains (accessions) of the best-characterized plant, Arabidopsis thaliana. Nonredundantly, 27% of the genome was included within the boundaries of PRs predicted at high specificity ( approximately 97%). The resulting data set provides a fine-scale view of polymorphic sequences in A. thaliana; patterns of polymorphism not apparent in SNP data were readily detected, especially for noncoding regions. Our predictions provide a valuable resource for evolutionary genetic and functional studies in A. thaliana, and our method is applicable to similar data sets in other species. More broadly, our computational approach can be applied to other segmentation tasks related to the analysis of genomic variation.     

A role for the basal ganglia in nicotinic modulation of the blink reflex

Summary In humans and rats we found that nicotine transiently modifies the blink reflex. For blinks elicited by stimulation of the supraorbital branch of the trigeminal nerve, nicotine decreased the magnitude of the orbicularis oculi electromyogram (OOemg) and increased the latency of only the long-latency (R2) component. For blinks elicited by electrical stimulation of the cornea, nicotine decreased the magnitude and increased the latency of the single component of OOemg response. Since nicotine modified only one component of the supraorbitally elicited blink reflex, nicotine must act primarily on the central nervous system rather than at the muscle. The effects of nicotine could be caused by direct action on lower brainstem interneurons or indirectly by modulating descending systems impinging on blink interneurons. Since precollicular decerebration eliminated nicotine's effects on the blink reflex, nicotine must act through descending systems. Three lines of evidence suggest that nicotine affects the blink reflex through the basal ganglia by causing dopamine release in the striatum. First, stimulation of the substantia nigra mimicked the effects of nicotine on the blink reflex. Second, haloperidol, a dopamine (D₂) receptor antagonist, blocked the effect of nicotine on the blink reflex. Third, apomorphine, a D₂ receptor agonist, mimicked the effects of nicotine on the blink reflex.     

CD146 protein in prostate cancer: revisited with two different antibodies

AIMS: CD146 is a potentially metastasis promoting cell adhesion molecule and its expression has been described in various solid tumours. We aimed to evaluate the expression of CD146 in prostate cancer by immunohistochemistry in a clinically characterised study cohort to evaluate its prognostic properties. METHODS: We evaluated the CD146 protein expression using a polyclonal and a monoclonal antibody on 169 clinico-pathologically characterised cases. Statistical analyses were applied to test for correlations and diagnostic and prognostic associations. RESULTS: CD146 detection with the polyclonal antibody revealed marked differential expression between tumour and normal tissue and was also a significant marker for shortened PSA relapse free survival. The monoclonal CD146 antibody demonstrated a weaker epithelial signal, which was significantly correlated with that of the polyclonal antibody, but revealed no prognostic value. However, the Western blot of the polyclonal antibody displayed a clearly reduced specificity. CONCLUSIONS: Evaluation of protein expression can be highly dependent on the primary antibody employed. A credible evaluation of antibody specificity is crucial to prove the validity of protein expression studies. The immunoreactivity of the polyclonal CD146 antibody (Abcam, ab28360) is prognostic of PSA-relapse in prostate cancer patients, although its immunoreactivity is possibly not restricted to CD146 associated epitopes.     

Running exercise of different duration and intensity: effect on endothelial progenitor cells in healthy subjects.

BACKGROUND: Increased numbers of circulating endothelial progenitor cells (EPC) are associated with improved vascular function. Exercise is a central component of the primary prevention of vascular diseases. The effect of physical activity on circulating EPC in healthy individuals is not known. DESIGN: A prospective crossover study. METHODS AND RESULTS: In order to study a potential link between the extent of physical exercise and progenitor cells in humans, EPC were quantified by flow cytometry and cell culture in 25 healthy volunteers undergoing three protocols of running exercise. Intensive running, defined as 30 min at 100% of the velocity of the individual anaerobic threshold (IAT; approximately 82% maximal oxygen consumption; VO2max), as well as moderate running with 30 min at 80% of the velocity of the IAT ( approximately 68% VO2max), increased circulating EPC numbers to 235+/-93% and 263+/-106% of control levels, respectively. However, moderate short-term running for 10 min did not upregulate EPC counts. The maximum increase in circulating EPC numbers was observed 10-30 min after intensive running. Exercise increased EPC migratory and colony-forming capacity. CONCLUSIONS: Intensive and moderate exercising for 30 min, but not for 10 min, increased circulating levels of EPC, which may represent an important beneficial outcome of physical exercise. The data support the notion that increased numbers of EPC correlate with cardiovascular health and suggest EPC quantification as a novel surrogate parameter of the vascular effects of exercising.     

Proliferation of human lens epithelial cells (HLE-B3) is inhibited by blocking of voltage-gated calcium channels

Calcium, as an integral part of a large number of cellular regulatory pathways, is selective in the control of specific cell functions like the start of G1 phase in cell cycle. Cell proliferation has been suggested to depend on increasing intracellular calcium levels. A major regulatory pathway for intracellular calcium is the calcium influx into the cell via voltage-gated calcium channels. T-type and L-type calcium channels are substantially present in human lens epithelial cell (hLEC), and total calcium currents are inhibited by mibefradil. Here, the hypothesis was tested if calcium influx via Ca_v channels regulates proliferation in epithelial cells. Cell proliferation was determined by cell culture assays using the L- and T-type Ca_v channel blockers mibefradil and verapamil as modulators for calcium influx. Calcium influx was investigated using the Manganese quench technique. Western blot experiments were accomplished under standard conditions using antibodies against MAPK 3. Mibefradil as well as verapamil impaired cell proliferation, but in different concentration ranges. Furthermore, the activation of MAPK 3 was reduced by both antagonists. Calcium influx was also reduced in the presence of both blockers. We conclude that the transmembrane influx of Ca²⁺ through Ca_v channels contributes to the regulation of hLEC proliferation, identifying Ca_v channel blockers as potential therapeutic substances in ocular diseases.