Species Differences in Spatial Memory Performance on a Three-dimensional Task

Three species of seed-caching corvids were tested in a spatial, three-dimensional analog of the radial maze. The apparatus consisted of five artificial trees, each with six branches. A wooden feeder could be attached to each branch. Each feeder contained a hole that could hold a pine seed. During the first 40 trials of acquisition testing, all three species improved rapidly with nutcrackers and pinyon jays performing at higher levels than scrub jays. Testing was then interrupted for 31 d. After the interruption, the two species of jays continued to improve but the nutcrackers did not. This species performed with only modest accuracy through the remainder of the experiment. Mixed-interval testing was done at 10, 60, 180, and 300 min. All species declined in accuracy with increased retention interval. However, at 10 and 180 min, pinyon jays performed significantly better than scrub jays. This is the fourth spatial memory task in which pinyon jays have out-performed scrub jays. The difference in performance between these two species provides more evidence for divergence in spatial cognition as a function of dependence on cached food.     

Dihydroisocoumarins and Phenylglycosides from Scorzonera longiana,Their Antimicrobial Activities and Molecular Docking Studies

Five new phenyl dihydroisocoumarin glycosides ( 1 – 5 ) and two known compounds ( 6 – 7 ) were identified from the butanol fraction of Scorzonera longiana. The structures of 1 – 7 were elucidated based on spectroscopic methods. Antimicrobial, antitubercular, and antifungal evaluation of compounds 1 – 7 were carried out using the microdilution method against nine microorganisms. Compound 1 was active only against Mycobacterium smegmatis (Ms) with a MIC value of 14.84 μg/mL. All tested compounds ( 1 – 7 ) were active against Ms but only compounds 3–7 were active against fungi (C. albicans, S. cerevisiae) with MIC values of 25.0–125 μg/mL. In addition, molecular docking studies were conducted against Ms DprE1 (PDB ID: 4F4Q), Mycobacterium tuberculosis (Mbt) DprE1 (PDB ID: 6HEZ), and arabinosyltransferase C (EmbC, PDB ID: 7BVE) enzymes. Compounds 2 , 5 , and 7 are the most effective Ms 4F4Q inhibitors. Compound 4 was the most promising inhibitory activity on Mbt DprE with the lowest binding energy of −9,9 kcal/mol.     

Preoperative levels of natriuretic peptides and the incidence of postoperative atrial fibrillation after noncardiac surgery: a prospective cohort study

BACKGROUND:Postoperative atrial fibrillation (POAF) is associated with clinically significant short- and long-term complications after noncardiac surgery. Our aim was to describe the incidence of clinically important POAF after noncardiac surgery and establish the prognostic value of N-terminal pro–brain-type natriuretic peptide (NT-proBNP) in this context.METHODS:The Vascular events In noncardiac Surgery patIents cOhort evaluatioN (VISION) Study was a prospective cohort study involving patients aged 45 years and older who had inpatient noncardiac surgery that was performed between August 2007 and November 2013. We determined 30-day incidence of clinically important POAF (i.e., resulting in angina, congestive heart failure, symptomatic hypotension or requiring treatment) using logistic regression models to analyze the association between preoperative NT-proBNP and POAF.RESULTS:In 37 664 patients with no history of atrial fibrillation, we found that the incidence of POAF was 1.0% (95% confidence interval [CI] 0.9%–1.1%; 369 events); 3.2% (95% CI 2.3%–4.4%) in patients undergoing major thoracic surgery, 1.3% (95% CI 1.2%–1.5%) in patients undergoing major nonthoracic surgery and 0.2% (95% CI 0.1%–0.3%) in patients undergoing low-risk surgery. In a subgroup of 9789 patients with preoperative NT-proBNP measurements, the biomarker improved the prediction of POAF risk over conventional prognostic factors (likelihood ratio test p < 0.001; fraction of new information from NT-proBNP was 16%). Compared with a reference NT-proBNP measurement set at 100 ng/L, adjusted odds ratios for the occurrence of POAF were 1.31 (95% CI 1.15–1.49) at 200 ng/L, 2.07 (95% CI 1.27–3.36) at 1500 ng/L and 2.39 (95% CI 1.26–4.51) at 3000 ng/L.INTERPRETATION:We determined that the incidence of clinically important POAF after noncardiac surgery was 1.0%. We also found that preoperative NT-proBNP levels were associated with POAF independent of established prognostic factors. Trial registration: ClinicalTrials.gov, no. {"type":"clinical-trial","attrs":{"text":"NCT00512109","term_id":"NCT00512109"}}NCT00512109

Postoperative atrial fibrillation (POAF) is the most common arrhythmia that occurs after noncardiac surgery¹ and is associated with prolonged hospital stays and an increased risk of stroke and death,^2–8 both of which raise societal costs.⁹ The reported incidence of POAF ranges from 3.7% to 21.0% in patients undergoing thoracic surgery^3,10 and from less than 0.5% to 10.0% in patients undergoing noncardiac, nonthoracic surgery (Appendix 1, Supplementary Table 1, available at www.cmaj.ca/lookup/doi/10.1503/cmaj.200840/tab-related-content).^6,11Brain-type natriuretic peptide (BNP) is a neurohormone released by cardiomyocytes in response to volume and pressure overload.¹² This biomarker has an established role in the diagnosis and management of heart failure and in predicting cardiovascular morbidity and mortality.¹³ Although natriuretic peptides have been shown to predict new-onset atrial fibrillation (AF) in the nonsurgical setting reliably,^14–18 their value in predicting POAF after noncardiac surgery is unclear.^19–21The Vascular events In non-cardiac Surgery patIents cOhort evaluatioN (VISION) Study was a prospective international cohort study involving a representative sample of adults who underwent noncardiac surgery that required an overnight hospital stay. One of the predefined objectives in VISION was to determine the incidence of new-onset, clinically important POAF. We aimed to describe the overall and surgery-specific incidence of POAF after noncardiac surgery and to investigate the association between preoperative N-terminal pro–brain-type natriuretic peptide (NT-proBNP) and POAF. We hypothesized that measurement of NT-proBNP would improve POAF risk prediction beyond conventional prognostic factors.     

Current biomarkers of canine mammary tumors

Mammary tumors are the second most common neoplasia in dogs. Due to the high similarity of canine mammary tumors (CMT) to human breast cancers (HBC), human biomarkers of HBC are also detectable in cases of CMT. The evaluation of biomarkers enables clinical diagnoses, treatment options and prognosis for bitches suffering from this disease. The aim of this article is to give a short summary of the biomarkers of CMT based on current literature. Very promising biomarkers are miRNAs, cancer stem cells, and circulating tumor cells, as well as mutations of the breast cancer 1 gene (BRCA1) and breast cancer 2 gene (BRCA2). Until now, the most studied and reliable biomarkers of CMT have remained antigen Ki-67 (Ki-67), endothelial growth factor receptor, human epidermal growth factor receptor 2 (HER-2), estrogen receptor, progesterone receptor and cyclooxygenase 1 (COX-2), which can be detected in both serum and tissue samples using different molecular methods. However, carcinoembryonic antigen and cancer antigen 15-3 (CA 15-3), while poorly studied, seem to be good biomarkers, especially for the early detection and prognosis of CMT. We will also mention the following: proliferative cell nuclear antigen, tumor protein p53 (p53), E-cadherin, vascular endothelial growth factor, microRNAs, cancer stem cells and circulating tumor cells, which can also be useful biomarkers. Although many studies have been conducted so far, the estimation of biomarkers in cases of CMT is still not a common practice, and more detailed research should be done.     

Clark's Nutcracker (Aves: Corvidae) Spatial Memory: Interference Effects on Cache Recovery Performance?

Clark's nutcrackers, Nucifraga columbiana, accurately v recover thousands of caches per year in the field. Previous experiments have confirmed that these birds possess excellent, long-lasting spatial-memory capabilities. We tested whether resistance to interference is one of the features of nutcracker spatial memory. Experiment 1 tested retroactive interference. Nutcrackers showed no decrease in accuracy overall but performed relatively poorly in their final recovery session. Interference is unlikely to have caused these sites to be poorly remembered because they had fewer neighbouring cache sites than better-remembered sites. Experiment 2 tested for proactive interference. Interference would have caused the experimental birds to be less accurate than control birds. Instead then were slightly more accurate. In experiment 3, nutcrackers were allowed to repeatedly view their cache sites from a cage between caching and recovery. Nutcrackers were less accurate when recovering from cache sites they had viewed. This effect may be due to changes in motivation. Order of caching had no effect on accuracy but nutcrackers were more accurate when recovering caches from central than from peripheral areas of experimental rooms. In summary, these experiments provide further evidence of the remarkable spatial-memory abilities of Clark's nutcrackers and demonstrate that these birds are highly resistant to interference effects on spatial memory. Comparative tests will be needed to test if specialized food storers are exceptionally resistant to interference in spatial memory.