TcBat a bat-exclusive lineage of Trypanosoma cruzi in the Panama Canal Zone, with comments on its classification and the use of the 18S rRNA gene for lineage identification

We report TcBat, a recently described genetic lineage of Trypanosoma cruzi, in fruit-eating bats Artibeus from Panama. Infections were common (11.6% prevalence), but no other T. cruzi cruzi genotypes were detected. Phylogenetic analyses show an unambiguous association with Brazilian TcBat, but raise questions about the phylogenetic placement of this genotype using the 18S rRNA gene alone. However, analyses with three concatenated genes (18S rRNA, cytb, and H2B) moderately support TcBat as sister to the discrete typing unit (DTU) TcI. We demonstrate that short fragments (>500 bp) of the 18S rRNA gene are useful for identification of DTUs of T. cruzi, and provide reliable phylogenetic signal as long as they are analyzed within a matrix with reference taxa containing additional informative genes. TcBat forms a very distinctive monophyletic group that may be recognized as an additional DTU within T. cruzi cruzi.     

Outcome in a post-cardiac surgery population with acute renal failure requiring dialysis: does age make a difference?

BACKGROUND: Acute renal failure (ARF), requiring dialysis (ARF-d), develops in 1-5% of patients undergoing cardiac surgery and is associated with higher in-hospital mortality. Age is one of the known risk factors for the development of ARF. As the ageing population is increasing, the nephrologist will be faced with a large population of elderly patients requiring dialysis following cardiac surgery. The aim of our study was to evaluate the influence of age on and the risk factors for in-hospital mortality. METHODS: Eighty-two patients with ARF following cardiac surgery and requiring dialysis between January 1997 and October 2001 were included. Two groups of patients were studied: the younger population (<70 years, 42 patients, mean age 59+/-10) and an elderly population (>/=70 years, 40 patients, mean age 76+/-4). Severity of disease was evaluated using the SAPS (Simplified Acute Physiology Score), the Liano score and the SHARF (Stuivenberg Hospital Acute Renal Failure) score. RESULTS: Overall mortality in the population with ARF-d was 56.1%. No difference in mortality rate was found between the younger (61.9%) and elderly patient group (50.0%). The two groups were very similar in baseline and procedural characteristics with exception of body weight (P=0.02) and preoperative glomerular filtration rate (P=0.0001). No significant difference was found in the scoring systems between the old and the young (SAPS P=0.52; Liano P=0.96; SHARF T0 P=0.06; SHARF T48 P=0.15). Mortality in the elderly was significantly correlated with hypotension before starting renal replacement therapy (RRT) (P=0.002), mechanical ventilation (P=0.002), presence of multiorgan failure (MOF) (P=0.0001) and higher scores in the severity models (SAPS: P=0.01; Liano: P<0.0001 and SHARF: P<0.0001). CONCLUSION: The outcome in the elderly requiring dialysis due to ARF post-cardiac surgery is comparable with the outcome in a younger population. No significant difference was found in severity of disease between the elderly and the younger. Variables predicting mortality in the elderly are the presence of MOF, mechanical ventilation and hypotension 24 h before starting RRT. These findings indicate that at the time the nephrologist is called for an elderly patient requiring dialysis due to ARF following cardiac surgery, age per se is not a reason to withhold RRT.     

Characterisation of additional mental foramina through cone beam computed tomography

Variations in jaw bone neurovascularisation must be identified to decrease the potential risk for haemorrhages and neural disturbances during surgical procedures such as implant placement and orthognatic surgeries. The aim of this study is to characterise additional mental foramina (AMF) through cone beam computed tomography (CBCT) images, by describing their frequency, size, location and direction of their associated bony canals, as well as to assess their corresponding ipsilateral and contralateral mental foramina (MF). CBCT images from 285 patients were analysed. Prevalence of AMF was 9·4%. From 0 to 2 AMF were observed, with two bilateral cases. Two cases of unilateral absence of MF were registered. Patients presenting AMF did not differ significantly from those without AMF regarding gender, age or ethnicity. Diameters of AMF and their corresponding ipsilateral and contralateral MF were 1·9 mm (±0·7 mm), 3·8 mm (±0·6 mm) and 4·1 mm (±0·6 mm), respectively. Ratios between diameters of AMF and corresponding ipsilateral MF ranged between 0·24 and 0·99. Location of AMF was variable, with most cases located posteriorly, posterior-inferiorly, posterior-superiorly or anterior-superiorly to their respective MF. Significant anatomical variability regarding neurovascularisation was observed among patients and CBCT examinations presented as a valuable tool for individually assessing these anatomical features.     

Improving strength and postural control in young skiers: whole-body vibration versus equivalent resistance training

Context: Several groups have undertaken studies to evaluate the physiologic effects of whole-body vibration (WBV). However, the value of WBV in a training program remains unknown. Objective: To investigate whether a WBV program results in a better strength and postural control performance than an equivalent exercise program performed without vibration. Design: Randomized, controlled trial. Setting: Laboratory. Patients or Other Participants: Thirty-three Belgian competitive skiers (ages = 9-15 years). Intervention(s): Subjects were assigned to either the WBV group or the equivalent resistance (ER) group for 6 weeks of training at 3 times per week. Main Outcome Measure(s): Isokinetic plantar and dorsiflexion peak torque, isokinetic knee flexion and extension peak torque, explosive strength (high box test), and postural control were assessed before and after the training period. Results: Both training programs significantly improved isokinetic ankle and knee muscle strength and explosive strength. Moreover, the increases in explosive strength and in plantar-flexor strength at low speed were significantly higher in the WBV group than in the ER group after 6 weeks. However, neither WBV training nor ER training seemed to have an effect on postural control. Conclusions: A strength training program that includes WBV appears to have additive effects in young skiers compared with an equivalent program that does not include WBV. Therefore, our findings support the hypothesis that WBV training may be a beneficial supplementary training technique in strength programs for young athletes.     

Anti-EGFR Resistance in Colorectal Cancer: Current Knowledge and Future Perspectives

Anti-EGFR therapy in metastatic colorectal cancer (mCRC) has improved survival outcome. However, many patients do not respond to this therapy and almost all patients develop resistance after a few months of treatment. Since 2008, the therapy has been restricted to patients without mutations in KRAS, an important target in the EGFR pathway, as these patients do not benefit from anti-EGFR therapy. Recently, this has been changed to an all-RAS wild-type strategy. Despite these restrictions, still 40 to 60 % of mCRC patients are resistant. New biomarkers need to be identified in order to improve patient selection. Another problem is tumor heterogeneity, which impedes the detection of mutations in resistance genes and can consequently lead to wrong treatment decisions. A possible solution for this problem may be found in liquid biopsies. In this review, known and promising upcoming biomarkers associated with resistance to anti-EGFR therapy will be summarized. Moreover, the potential added value of liquid biopsies in patient selection and follow-up will be discussed.     

Angiostatic,tumor inflammatory and anti-tumor effects of CXCL447–70 and CXCL4L147–70 in an EGF-dependent breast cancer model

CXCL4 and CXCL4L1, platelet-derived CXC chemokines, and their carboxy-terminal peptides CXCL4^47–70 and CXCL4L1^47–70 previously displayed angiostatic and anti-tumoral activity in a melanoma model. Here, we found CXCL4^47–70 and CXCL4L1^47–70 to inhibit lymphatic endothelial cell proliferation in vitro. Furthermore, the angiostatic potential of CXCL4^47–70 and CXCL4L1^47–70 was tested against different angiogenic stimuli (FGF1, FGF2, FGF8, EGF and VEGF). Besides reducing FGF2-induced vascular endothelial cell growth, CXCL4^47–70 and CXCL4L1^47–70 efficiently counteracted EGF. Consequently, we considered their anti-tumoral potential in EGF-dependent MDA-MB-231 breast tumors. In tumor-bearing mice, CXCL4^47–70 reduced tumor growth better than CXCL4L1^47–70. In CXCL4^47–70-treated tumors significantly more intratumoral monocytes/macrophages and dendritic cells were present and higher expression levels of CCL5 and IFN-γ were detected by qPCR on tumor lysates. Because neither peptide was able to specifically bind CXCR3A or CXCR3B, differential glycosaminoglycan binding and direct interaction with cytokines (EGF and CCL5) might explain any differences in anti-tumoral effects. Notably, CCL5-induced monocyte chemotaxis in vitro was increased by addition of CXCL4^47–70 or CXCL4L1^47–70. Finally, CXCL4^47–70 and CXCL4L1^47–70 inhibited proliferation of MDA-MB-231 cells. Our results suggest a tumor type-dependent responsiveness to either CXCL4^47–70 or CXCL4L1^47–70 treatment, defined by anti-proliferative, angiostatic and inflammatory actions, and substantiate their therapeutic potential.