Topographical Subcomponents of Electrical Brain Activity Allow to Identify Semantic Learning

We investigated the change of event-related brain activity elicited by reading meaningful or meaningless Japanese symbols in 20 healthy German adults. In a learning phase of about 20 min, subjects acquired the meaning of 20 Kanji characters. As control stimuli 20 different Kanji characters were presented. Electrical brain activity was obtained before and after learning, The mean learning performance of all subjects was 92.5% correct responses. EEG was measured simultaneously from 30 channels, artifacts were removed offline, and the data before and after learning were compared. We found five spatial principal components that accounted for 83.8% of the variance. A significant interaction between training time (before/after learning) and stimulus (learning/control) illustrates a significant relation between successful learning and topographical changes of brain activity elicited by Kanji characters. Effects that were induced by learning were seen at short latencies in the order of 100 ms. In addition, we present evidence that differences in the weighted combination of spatial components allow to identify experimental conditions successfully by linear discriminant analysis using topographical ERP data of a single time point. In conclusion, semantic meaning can be aquired rapidly and it is associated with specific changes of ERP components.     

Otolith dysfunction during vertiginous attacks in Ménière's disease

OBJECTIVE: Vertiginous attacks of Ménière's disease (MD) are characterized by various types of vertigo, namely rotatory vertigo, dizziness and drop attack. When a patient complains of dizziness without spontaneous nystagmus, otolith dysfunction cannot be ruled out. The purpose of this study was to evaluate otolith dysfunction during vertiginous attacks of MD or delayed endolymphatic hydrops. MATERIAL AND METHODS: Vestibular function tests were carried out daily for several days in 11 patients (MD, n = 9; delayed endolymphatic hydrops, n = 2) during vertiginous attacks. Otolith function was evaluated by means of the static torsional position of both eyes [static ocular torsion (OT)] whilst in an upright position. We defined otolith dysfunction as an abnormal change (range) in OT without spontaneous nystagmus or as an abnormal change in OT without a change in spontaneous nystagmus. RESULTS: Four patients had an abnormal change (range) in OT without spontaneous nystagmus or an abnormal change in OT without a change in spontaneous nystagmus during vertiginous attacks of MD. CONCLUSIONS: Otolith dysfunction occurs in patients during vertiginous attacks of MD. In cases of ataxia without spontaneous nystagmus, otolith dysfunction most likely causes atypical attacks of MD.     

Gas Exchange Function Through the Mastoid Mucosa in Ears After Surgery

Gas exchange function through the mastoid mucosa was investigated in ears after surgery using nitrous oxide. Increase in the mastoid pressure was assessed by a micropressure sensor placed in the mastoid cavity during the second-stage revision operation performed under general anesthesia using 67% nitrous oxide, 33% oxygen, and sevoflurane on 14 ears with chronic adhesive otitis media or cholesteatoma as well as on seven ears without inflammation as controls. All seven control ears showed pressure increase in the mastoid in various degrees. In the 14 postoperative ears, nine of the 10 ears on which the mastoid mucosa had previously been able to be preserved in various degrees showed pressure increase in the mastoid, but none of the remaining four ears, which had previously had mastoidectomy, showed any pressure increase. The presence or absence of the mastoid pressure increase of those ears was also found to be correlated well with the presence or absence of mastoid aeration on computed tomography examined just before the second-stage operation. These results appear to indicate that, in ears after surgery, recovery of both the gas exchange function and aeration in the mastoid is expected only when the mastoid mucosa can be preserved even partially.     

Characterization of Salmonella enterica serovar Typhimurium isolates harboring a chromosomally encoded CMY-2 beta-lactamase gene located on a multidrug resistance genomic island

Since 2004, extended-spectrum cephalosporin (ESC)-resistant Salmonella enterica serovar Typhimurium (S. Typhimurium) isolates have been detected from cattle in the northern major island of Japan, Hokkaido. Resistance to ESCs was found to be mediated by CMY-2 type β-lactamase among 22 epidemiologically unrelated isolates showing indistinguishable pulsed-field gel electrophoresis patterns. Southern blot analysis using I-CeuI-digested genomic DNA demonstrated that the CMY-2 β-lactamase gene (bla(CMY-2)) was integrated in a 2.5-Mb chromosomal fragment. Genetic analysis of S. Typhimurium isolate L-3553 indicated that bla(CMY-2) was located on a unique 125-kb genomic island, GI-VII-6, which consists of 140 open reading frames. Pairwise alignment of GI-VII-6 and Escherichia coli plasmid pAR060302 (size, 167 kb) revealed that a large proportion of GI-VII-6 (99%) shows a high sequence similarity (>99%) with pAR060302. GI-VII-6 contains 11 antimicrobial resistance genes including sul1, qacEΔ1, aadA2, and dfrA12 in the aadA2 region; sugE1 and bla(CMY-2) in the bla(CMY-2) region; and sul2, strA, strB, tet(A), and floR in the floR region. Two directly repeated IS26 copies were present at both ends of GI-VII-6. Junction regions of GI-VII-6 were flanked by an 8-bp direct repeat, indicating that GI-VII-6 was acquired by transposition involving IS26 transposase. PCR scanning revealed that the overall structure of GI-VII-6 was almost identical in the 22 isolates. Phylogenetic analysis suggested that S. Typhimurium isolates harboring GI-VII-6 belong to a different genomic lineage than other whole-genome-sequenced S. Typhimurium strains. These data indicate that a particular clone of S. Typhimurium harboring GI-VII-6 has spread among the cattle population in Hokkaido, Japan.     

Renin-angiotensin system blocker use may be associated with suppression of atrial fibrillation recurrence after pulmonary vein isolation

Introduction: An additional approach may be essential to reduce recurrences of atrial fibrillation (AF) after pulmonary vein isolation (PVI). We examined the efficacy of renin‐angiotensin system blockers (RAS‐B) in suppressing AF recurrences after PVI. Methods and Results: We retrospectively studied 264 consecutive patients (195 male, median age: 63 years) who underwent successful PVI of paroxysmal (n = 94) or persistent AF (n = 170). RAS‐B treatment was performed in 145 patients (angiotensin‐converting enzyme inhibitors; n = 13, angiotensin receptor blockers; n = 129, both; n = 3). Echocardiography was performed before and 3 months after the ablation to examine the occurrence of left atrial structural reverse remodeling (LA‐RR). After a median follow‐up of 195 (interquartile range: 95–316) days, AF recurred in 51 (19.3%) patients. A Cox regression analysis revealed that AF recurrence was significantly lower in the patients with RAS‐B than in those without (hazard ratio [HR] = 0.41 [95% confidence interval (CI): 0.23–0.71], P = 0.002). After a multivariate adjustment for potential confounders, the use of RAS‐B (HR = 0.39 [95% CI: 0.19–0.77], P = 0.007) and type of AF (HR = 0.30 [95% CI: 0.13–0.66], P = 0.003) were the independent predictors for AF recurrence during the entire follow‐up. Although effect of RAS‐B was not significant during the early follow‐up (<3 month), it was the only independent predictor during the late follow‐up (>3 months) (HR = 0.21 [95% CI: 0.08–0.53], P = 0.001). There were no significant differences in LA‐RR occurrence regarding RAS‐B medication. The use of RAS‐B was an independent predictor of late AF recurrences irrespective of an early LA‐RR occurrence. Conclusions: Treatment with RAS‐B significantly reduced the AF recurrence after PVI. This benefit became more prominent 3 months after the PVI. (PACE 2011; 34:296–303)     

Sec1-FUT2-Sec1 hybrid allele generated by interlocus gene conversion

BACKGROUND: Many single-nucleotide polymorphisms have been identified in the coding region of the FUT2 locus, which encodes secretor type α(1,2)fucosyltransferase. In addition, three recombination alleles have been reported. Of these recombination alleles, a fusion gene generated by an unequal crossing over between Sec1 , a pseudogene that locates 23 kb upstream to and has high sequence homology with FUT2 and FUT2, was identified as a Japanese-specific nonsecretor allele ( se ^fus ).
STUDY DESIGN AND METHODS: During the screening of the se ^fus in Mongolians (n = 118), a hybrid allele of Sec1-FUT2-Sec1 was found.
RESULTS: The DNA sequence suggested that the Sec1-FUT2-Sec1 allele contains a 275-bp sequence (between positions 259 and 533) that is identical to the FUT2 sequence including a 54-bp FUT2- specific region (between positions 417 and 470) and that might have been generated by an interlocus gene conversion.
CONCLUSION: Because the recombination region of se ^fus and the upstream recombination region of Sec1-FUT2-Sec1 are almost identical, this sequence stretch is likely to be the breakpoint for different kinds of recombinations that occur in this family of genes.     

Lethality of shock pressures to a marine Vibrio sp. isolated from a ship's ballast water

The lethal effects of shock pressure treatment on suspended Vibrio sp. cells were examined. Lethality of shock pressures to the Vibrio sp. cells increased with the increase in the values of maximum shock pressures generated in the cell suspension. When the value was around 114 MPa, the total number of colony-forming cells was reduced from 10(8.5+/-0.1) colony-forming units (CFU) to 10(3.3) - 10(3.4) CFU/ml, and complete loss of colony-forming ability was seen at the maximum value of 282 MPa. Almost all the cells could survive after the exposure to shock pressures including the maximum value of around 189 MPa in the presence of 2% sodium ascorbate (VitC-Na), whereas the total number of colony-forming cells was reduced to 10(1.6)-10(2.1) CFU/ml in the absence of VitC-Na. The surviving cells, however, showed sensitivity to 0.8% sodium cholate, a strong detergent. About 11% of cell-associated proteins had leaked out when the cells were exposed to lethal shock pressures including the maximum value of around 290 MPa in the absence of VitC-Na. These results indicate that the radicals generated in the cell suspension may be closely related to the loss of colony-forming ability of the Vibrio sp. cells. Damage to the outer membrane structure also seems to have occurred by the exposure to shock pressures.     

Value of washed sputum gram stain smear and culture for management of lower respiratory tract infections in children

To date, the technique of washed sputum examinations has not been widely used in the clinical management of lower respiratory tract infections in children. A total of 224 sputum samples from 125 pediatric patients with lower respiratory tract infections were collected for washed sputum Gram stain smears and cultures. The results with these methods were compared to find correlation rates. The value of washed sputum cultures was assessed by examining the clinical responses of the patients who received antibiotic therapies instituted on the basis of the sputum culture results. Isolation rates of Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis, and Staphylococcus aureus were 22.4%, 9.4%, 4.9%, and 0.4%, respectively. For the prediction of H. influenzae, S. pneumoniae, and M. catarrhalis, the sensitivities of the washed sputum Gram stain smears compared with the culture method were 86.0%, 81.0%, and 90.9%, respectively. The specificities of the washed sputum Gram stain smear technique were 94.8%, 97.5%, and 98.1%, respectively. Overall, the sensitivity and specificity of the washed sputum Gram stain smear method were 85.5% and 87.2%, respectively. S. aureus was isolated from only one specimen; and washed sputum Gram stain smear estimation was correlated with the culture result. On the basis of the washed sputum culture results, appropriate antibiotic therapies were instituted for 93.3% of the patients with acute lower respiratory tract infections. This study suggests that the techniques of washed sputum Gram stain smear and culture are valuable and should be encouraged in clinical practice for the management of lower respiratory tract infections in children.