Bilateral MR volumetry of the amygdala in chronic PTSD patients

Posttraumatic stress disorder (PTSD) patients experience symptoms which implicate dysfunction of emotional memory circuits, and possible damage of the amygdala. Laterality differences in activity of the amygdala have been reported in PTSD patients, with presumed adaptive plasticity in the hippocampus and the amygdala. The aim of this study was to investigate possible interhemispheric differences of amygdalar volume in chronic PTSD patients, with calculation of right-to-left volume ratios. Bilateral magnetic resonance (MR) volumetry was applied in 11 chronic PTSD patients. The mean right amygdalar volume of our patients was significantly smaller than the left one (p = 0.031), with the right-to-left volume ratio of 0.96 +/- 0.06. This tendency towards smaller right amygdala may be an acquired effect as a result of stress-induced plasticity, however we can not exclude the possibility of a predisposing condition.     

Synthesis and antiproliferative activity of two new tiazofurin analogues with 2'-amido functionalities

Two novel tiazofurin analogues 2 and 3 were synthesized starting from d-glucose. The key step of the synthesis was the efficient one-step hydrogen sulfide-mediated conversion of 2-azido-3-O-acyl-ribofuranosyl cyanides to the corresponding 2-amido thiocarboxamides. Compounds 2 and 3 were evaluated for their in vitro antiproliferative activity against certain human tumour cell lines. Remarkably, compound 2 was found to be 570-fold more potent than tiazofurin against MCF-7 cells, while compound 3 showed the most powerful cytotoxicity against HT-29 cancer cells, being almost 100-fold more active than tiazofurin.     

Detection of salivary interleukin 2 and interleukin 6 in patients with burning mouth syndrome

The etiology of BMS remains unknown. Role of various cytokines has been implicated in the development of BMS. The aim of this study was to evaluate levels of salivary IL-2 and IL-6 in patients with BMS, compared with age-matched healthy volunteers (control group). Whole saliva from 30 patients with BMS, age range 55-65, was tested for the presence of IL-6 and IL-2 by enzyme immunoassay. Control group consisted of 30 healthy participants, aged 55-65 years. Saliva IL-2 concentrations in BMS were significantly increased in patients compared to healthy subjects: mean 34.1 +/- 9.7 versus 7.3 +/- 3.0 pg/mL; P < .001. Patients with BMS had significantly higher concentrations of IL-6 compared to control: mean 30.8 +/- 5.6 versus 5.2 +/- 2.8 pg/mL; P < .001. In patients with BMS, IL-2 and IL-6 levels in saliva are elevated, correlating with the severity of illness.     

Distribution of Several Activating and Inhibitory Receptors on CD3<Superscript>−</Superscript>CD16<Superscript>+</Superscript> NK Cells and Their Correlation with NK Cell Function in Healthy Individuals

The aim of this study was to estimate the distribution and density of a representative set of activating and inhibitory receptors on gated natural killer (NK) cells, as well as on their bright and dim subsets, and to correlate the receptor expression with NK cell activity for healthy individuals on CD3⁻CD16⁺ NK cells. We show that in 43 healthy controls NK cell activity against K562 target cells was 37.34% (E:T, 80:1) by standard chromium release assay. The expression of receptors on NK cells and their subsets was analyzed by flow cytometry. The cytotoxic CD3⁻CD16^bright NK subset constituted 78.97%, while the regulatory CD3⁻CD16^dim NK subset constituted 21.03% of NK cells. We show the distribution of NKG2D, CD161, CD158a, and CD158b receptors on CD3⁻CD16⁺ NK cells in peripheral blood lymphocytes (PBLs), on gated NK cells, and on the CD3⁻CD16^bright and CD3⁻CD16^dim subsets. Contrary to CD158a and CD158b killer immunoglobulin-like receptors (KIRs), there is a significant positive correlation of NKG2D and CD161 expression with NK cytotoxicity. We show the kinetics of change in CD3⁻CD16⁺NK/K562 conjugate composition, together with the stronger target binding capacity of CD16^bright NK cells. Furthermore, we show that after coculture of PBLs with K562 the expression of CD107a, a degranulation marker, on CD3⁻CD16⁺NK cells and subsets is time dependent and significantly higher on the cytotoxic CD3⁻CD16^bright NK subset. The novel data obtained regarding expression of NK cell activating and inhibitory receptors for healthy individuals may aid in detecting changes that are associated with various diseases.     

Sorption properties of TEMPO-oxidized natural and man-made cellulose fibers

Cotton and lyocell fibers were oxidized with sodium hypochlorite and catalytic amount of sodium bromide and 2,2,6,6-tetramethylpiperidine-1-oxy radical (TEMPO), under various conditions. Water-insoluble fractions, collected after TEMPO-mediated oxidation, were analyzed and characterized in terms of weight loss, aldehyde and carboxyl contents, and sorption properties. Aldehyde and carboxyl groups were introduced into the oxidized cotton up to 0.321 and 0.795 mmol/g, and into the oxidized lyocell up to 0.634 and 0.7 mmol/g, respectively, where weight loss was generally lower than 12% for cotton and 27% for lyocell. Oxidized cotton and lyocell were shown to exhibit 1.55 and 2.28 times higher moisture sorption than the original fibers, respectively, and water retention values up to about 85% for cotton and 335% for lyocell, while iodine sorption values of oxidized fibers were lower up to 35% for cotton and up to 18% for lyocell than the original fibers.     

Characterization of microsatellite loci for the pitcher plant midge, Metriocnemus knabi Coq. (Diptera: Chironomidae)

As a component of the inquiline community of the purple pitcher plant (Sarracenia purpurea), the pitcher plant midge Metriocneus knabi has been the subject of various ecological studies. However, very little is known about its characteristics beyond the larval stage, in particular the dispersal ability of adults. This study presents new molecular tools developed for testing of evolutionary and ecological questions in natural populations of this species. We describe a set of 12 microsatellite loci specific to M. knabi that are sufficiently polymorphic to provide insight into population genetic structure and dispersal patterns.     

The aminoglycoside resistance methyltransferase Sgm impedes RsmF methylation at an adjacent rRNA nucleotide in the ribosomal A site

Ribosome-targeting antibiotics block protein synthesis by binding at functionally important regions of the bacterial rRNA. Resistance is often conferred by addition of a methyl group at the antibiotic binding site within an rRNA region that is already highly modified with several nucleotide methylations. In bacterial rRNA, each methylation requires its own specific methyltransferase enzyme, and this raises the question as to how an extra methyltransferase conferring antibiotic resistance can be accommodated and how it can gain access to its nucleotide target within a short and functionally crowded stretch of the rRNA sequence. Here, we show that the Sgm methyltransferase confers resistance to 4,6-disubstituted deoxystreptamine aminoglycosides by introducing the 16S rRNA modification m⁷G1405 within the ribosomal A site. This region of Escherichia coli 16S rRNA already contains several methylated nucleotides including m⁴Cm1402 and m⁵C1407. Modification at m⁵C1407 by the methyltransferase RsmF is impeded as Sgm gains access to its adjacent G1405 target on the 30S ribosomal subunit. An Sgm mutant (G135A), which is impaired in S-adenosylmethionine binding and confers lower resistance, is less able to interfere with RsmF methylation on the 30S subunit. The two methylations at 16S rRNA nucleotide m⁴Cm1402 are unaffected by both the wild-type and the mutant versions of Sgm. The data indicate that interplay between resistance methyltransferases and the cell''s own indigenous methyltransferases can play an important role in determining resistance levels.     

Aerobic exercise and snoring in overweight children: a randomized controlled trial

Objective: To determine whether regular aerobic exercise improves symptoms of sleep‐disordered breathing in overweight children, as has been shown in adults. Research Methods and Procedures: Healthy but overweight (BMI ≥85th percentile) 7‐ to 11‐year‐old children were recruited from public schools for a randomized controlled trial of exercise effects on diabetes risk. One hundred children (53% black, 41% male) were randomly assigned to a control group (n = 27), a low‐dose exercise group (n = 36), or a high‐dose exercise group (n = 37). Exercise groups underwent a 13 ± 1.5 week after‐school program that provided 20 or 40 minutes per day of aerobic exercise (average heart rate = 164 beats per minute). Group changes were compared on BMI z‐score and four Pediatric Sleep Questionnaire scales: Snoring, Sleepiness, Behavior, and a summary scale, Sleep‐Related Breathing Disorders. Analyses were adjusted for age. Results: Both the high‐dose and low‐dose exercise groups improved more than the control group on the Snoring scale. The high‐dose exercise group improved more than the low‐dose exercise and control groups on the summary scale. No group differences were found for changes on Sleepiness, Behavior, or BMI z‐score. At baseline, 25% screened positive for sleep‐disordered breathing; half improved to a negative screen after intervention. Discussion: Regular vigorous exercise can improve snoring, a symptom of sleep‐disordered breathing, in overweight children. Aerobic exercise programs may be valuable for prevention and treatment of sleep‐disordered breathing in overweight children.     

Effect of l-arginine on metabolism of polyamines in rat’s brain with extrahepatic cholestasis

Cholestatic encephalopathy results from accumulation of unconjugated bilirubin and hydrophobic bile acids in the brain. The aim of this study was to determine disturbances of polyamine metabolism in the brains of rats with experimental extrahepatic cholestasis and the effects of l-arginine administration. Wister rats were divided into groups: I: sham-operated, II: rats treated with l-arginine, III: animals with bile-duct ligation (BDL), and IV: cholestatic-BDL rats treated with l-arginine. Increased plasma γ-glutamyltransferase and alkaline phosphatase activity and increased bile-acids and bilirubin levels in BDL rats were reduced by administration of l-arginine (P < 0.001). Cholestasis increased the brain’s putrescine (P < 0.001) and decreased spermidine and spermine concentration (P < 0.05). The activity of polyamine oxidase was increased (P < 0.001) and diamine oxidase was decreased (P < 0.001) in the brains of BDL rats. Cholestasis increased the activity of arginase (P < 0.05) and decreased the level of citrulline (P < 0.001). Administration of l-arginine in BDL rats prevents metabolic disorders of polyamines and establishs a neuroprotective role in the brain during cholestasis.