Investigation of Stress Levels before the Onset of Idiopathic Sudden Sensorineural Hearing Loss.

OBJECTIVES: We hypothesized that patients with idiopathic sudden sensorineural hearing loss (ISSHL) would have experienced more stress prior to the onset than they typically did. This study investigated stress levels in patients before the onset of ISSHL. MATERIALS AND METHODS: Forty-two patients with ISSHL were investigated. We used an original questionnaire to evaluate subjective stress levels in 1 week before onset. Serum hemoglobin A1c (HbA1c) and total cholesterol were examined to evaluate biochemical stress markers reflecting the preceding 1 to 2 months. The results on admission were compared with those at the follow-up visit. RESULTS: Significantly more patients reported greater physical exhaustion, greater mental exhaustion, or a worse physical condition on admission than at follow-up (p<0.01, for each variable). On admission, 81% of patients reported greater than normal stress with regard to at least 1 of 3 items. The mean serum HbA1c was slightly but nonsignificantly lower at the follow-up visit (p=0.10), while the mean serum total cholesterol was significantly lower at follow-up than on admission (p<0.01). CONCLUSION: The results indicate that patients were under a greater degree of stress before the onset of ISSHL, suggesting that stress plays a role in inducing ISSHL.

Self-reported symptoms in patients with idiopathic sudden sensorineural hearing loss.

OBJECTIVE: This study evaluated self-reported symptoms in patients with idiopathic sudden sensorineural hearing loss (ISSHL). STUDY DESIGN: Cross-sectional study. SETTING: Multicenter clinical investigation in 9 university hospitals. PATIENTS: In total, 140 patients with ISSHL and 24 patients with unilateral sensorineural hearing loss (USHL; control) were included. MAIN OUTCOME MEASURES: A questionnaire on symptoms of ISSHL was distributed and the Short-Form Health Survey (Version 2) was used for assessing the quality of life. RESULTS: In response to questions on hearing difficulty, many of patients in both groups experienced symptoms. In response to questions on hearing-related discomfort, a significantly higher number of patients with ISSHL experienced symptoms compared with those with USHL. Compared with a high incidence of tinnitus in patients with ISSHL, very low incidence of tinnitus was observed in those with USHL.In the multiple linear regression analysis, hearing-related discomfort was the sole significant factor on the Mental Component Summary scores of the Short-Form Health Survey (Version 2). CONCLUSION: Many patients with ISSHL experience several symptoms such as hearing difficulty, hearing-related discomfort, tinnitus, and anxiety. Hearing-related discomfort strongly affected the quality of life in patients with ISSHL.

Contribution of momilactone A and B to rice allelopathy.

Eight cultivars of rice (Oryza sativa L.) inhibited shoot and root growth of Echinochloa crus-galli when co-cultured with rice seedlings in a bioassay medium. Momilactone A and B were found in the bioassay medium of all rice cultivars, and concentrations of momilactone A and B in the medium were 0.21-1.5 and 0.66-3.8 micromol/L, respectively, indicating that all rice cultivars may secrete momilactone A and B into the medium. Exogenously applied momilactone A and B inhibited the growth of shoots and roots of E. crus-galli at concentrations greater than 30 and 1 micromol/L, respectively. The concentrations required for 50% growth inhibition of E. crus-galli shoots and roots, respectively, were 146 and 91 micromol/L for momilactone A and 6.5 and 6.9 micromol/L for momilactone B. Considering the growth inhibitory activity and concentrations found in the bioassay medium, momilactone A may have caused only 0.8-2.2% of the observed growth inhibition of E. crus-galli roots and shoots by rice. However, momilactone B in the medium was estimated to be able to cause 59-82% of the observed growth inhibition of E. crus-galli roots and shoots by the rice seedlings. In addition, the concentrations of momilactone B in the medium reflected the observed differences in the growth inhibition of E. crus-galli by the eight rice cultivars investigated. This suggests that the allelopathic activity of rice may depend primarily on the secretion level of momilactone B. Therefore, momilactone B may play a very important role in rice allelopathy.

Edaravone, a free radical scavenger, in the treatment of idiopathic sudden sensorineural hearing loss with profound hearing loss.

OBJECTIVE: Edaravone, a free radical scavenger, is a clinical drug that is widely used to reduce neuronal damage after acute cerebral infarction in Japan since 2001. The aim of this study was to investigate whether edaravone could improve treatment result in idiopathic sudden sensorineural hearing loss (ISSHL) patients with severe hearing loss. METHODS: Between 2004 and 2006, 14 patients of ISSHL with the mean hearing levels equal or over 90dB at the initial visit were treated with edaravone. 14 counterpart control patients were selected from 45 patients who had similar prognostic factors and were treated with hyperbaric oxygenation therapy (HBO) in the past decade. RESULTS: There were no significant differences between edaravone group and the control group in hearing recovery. CONCLUSION: We considered that edaravone was not able to bring remarkable effect compared with conventional treatment regimen for ISSHL.

Noninvasive diagnosis of cardiac sarcoidosis using microvolt T-wave alternans.

Sarcoidosis is a systemic granulomatous disorder whose prognosis worsens when the heart is involved, and early diagnosis is important. Endomyocardial biopsy is the most helpful diagnostic examination, but suffers from low sensitivity and low specificity. Microvolt T wave alternans (MVTWA) is utilized in noninvasive examinations to detect beat-to-beat changes in the shape of the T wave at the microvolt level. Such beat-to-beat T wave changes arise from beat-to-beat changes in the transmural gradient of action potential duration. We speculate that the granulomatous changes of cardiac sarcoidosis produce cell-to-cell uncoupling and augment the transmural gradients of action potential duration. To examine the clinical significance of MVTWA in the prediction of cardiac involvement in sarcoidosis patients, we obtained MVTWA in a total of 35 sarcoidosis patients with and without cardiac involvement. All patients underwent electrocardiography (ECG), ambulatory electrocardiography, chest radiography, transthoracic echocardiography, and MVTWA examination using a CH 2000 system. We diagnosed cardiac sarcoidosis in 7 patients according to the accepted diagnostic criteria. MVTWA was detected in 6 out of 7 cardiac sarcoidosis patients (85.7%) as opposed to in 2 out of 28 patients without cardiac involvement (7.1%). The difference between the two groups was statistically significant (P < 0.001). The sensitivity and specificity of MVTWA in cardiac sarcoidosis detection were 85.7% and 92.8%, respectively. The positive and negative predictive values were 75% and 96.3%, respectively, with an overall accuracy of 91.4%. Noninvasive examination of MVTWA using a CH 2000 is a useful diagnostic tool for detecting cardiac involvement in patients with sarcoidosis.

Secretion of momilactone A from rice roots to the rhizosphere.

The secretion levels of momilactone A from rice (Oryza sativa L.) seedlings of eight cultivars into the rhizosphere were compared with the endogenous momilactone A concentrations in their shoots and roots. All rice cultivars contained momilactone A in the shoots and roots, and concentrations differed among the cultivars. Momilactone A was also found in all culture solutions in which the rice seedlings were grown, and the concentrations differed among the cultivars. The momilactone A concentrations in the culture solutions were reflected in the momilactone A concentrations in the shoots. These results suggest that all rice cultivars may produce momilactome A and secrete momilactone A into the culture solutions. The secretion levels of momilactone A may be more dependent on their capacities for momilactone A production in the shoots than on their capacities for momilactone A transportation from the shoots into the environment via the roots. As momilactone A acts as an antimicrobial and allelopathic agent, the secretion of momilactone A into the rice rhizosphere may provide a competitive advantage for root establishment through local suppression of soil microorganisms and inhibition of the growth of competing plant species.

The VA relationship after differential atrial overdrive pacing: a novel tool for the diagnosis of atrial tachycardia in the electrophysiologic laboratory.

INTRODUCTION: Despite recent advances in clinical electrophysiology, diagnosis of atrial tachycardia (AT) originating near Koch's triangle remains challenging. We sought a novel technique for rapid and accurate diagnosis of AT in the electrophysiologic laboratory. METHODS: Sixty-two supraventricular tachycardias including 18 ATs (10 ATs arising from near Koch's triangle), 32 atrioventricular nodal reentrant tachycardias (AVNRTs), and 12 orthodromic reciprocating tachycardias (ORTs) were studied. Overdrive pacing during the tachycardia from different atrial sites was performed, and the maximal difference in the postpacing VA intervals (last captured ventricular electrogram to the earliest atrial electrogram of the initial beat after pacing) among the different pacing sites was calculated (delta-VA interval). RESULTS: The delta-VA intervals were >14 ms in all AT patients and <14 ms in all AVNRT/ORT patients, and thus, the delta-VA interval was diagnostic for AT with the sensitivity, specificity, and positive and negative predictive values all being 100%. When the diagnostic value of the delta-VA interval and conventional maneuvers were compared for differentiating AT from atypical AVNRT, both a delta-VA interval >14 ms and "atrial-atrial-ventricular" response after overdrive ventricular pacing during the tachycardia were diagnostic. However, the "atrial-atrial-ventricular" response criterion was available in only 52% of the patients because of poor ventriculoatrial conduction. CONCLUSIONS: The delta-VA interval was useful for diagnosing AT irrespective of patient conditions such as ventriculoatrial conduction.

'Crystal lattice engineering,' an approach to engineer protein crystal contacts by creating intermolecular symmetry: crystallization and structure determination of a mutant human RNase 1 with a hydrophobic interface of leucines.

A protein crystal lattice consists of surface contact regions, where the interactions of specific groups play a key role in stabilizing the regular arrangement of the protein molecules. In an attempt to control protein incorporation in a crystal lattice, a leucine zipper-like hydrophobic interface (comprising four leucine residues) was introduced into a helical region (helix 2) of the human pancreatic ribonuclease 1 (RNase 1) that was predicted to form a suitable crystallization interface. Although crystallization of wild-type RNase 1 has not yet been reported, the RNase 1 mutant having four leucines (4L-RNase 1) was successfully crystallized under several different conditions. The crystal structures were subsequently determined by X-ray crystallography by molecular replacement using the structure of bovine RNase A. The overall structure of 4L-RNase 1 is quite similar to that of the bovine RNase A, and the introduced leucine residues formed the designed crystal interface. To characterize the role of the introduced leucine residues in crystallization of RNase 1 further, the number of leucines was reduced to three or two (3L- and 2L-RNase 1, respectively). Both mutants crystallized and a similar hydrophobic interface as in 4L-RNase 1 was observed. A related approach to engineer crystal contacts at helix 3 of RNase 1 (N4L-RNase 1) was also evaluated. N4L-RNase 1 also successfully crystallized and formed the expected hydrophobic packing interface. These results suggest that appropriate introduction of a leucine zipper-like hydrophobic interface can promote intermolecular symmetry for more efficient protein crystallization in crystal lattice engineering efforts.

UV-induced momilactone B accumulation in rice rhizosphere.

UV-irradiation increased the concentration of momilactone B in shoots and roots of rice seedlings, and increasing the irradiation increased the concentration. The concentration in 90-min UV-irradiated shoots and roots, respectively, was 31.8- and 3.6-fold higher than that in non-irradiated shoots and roots. After UV-irradiation the concentration of momilactone B in rice shoots decreased. There was, however, an accumulation of momilactone B in the medium in which UV-irradiated seedlings were grown. Five days after UV-irradiation, momilactone B in the medium was at a level 2.5 times greater than on day 0, which was 47% of momilactone B in the seedlings, suggesting that rice may actively secrete momilactone B into medium. Therefore, UV-irradiation increased not only production of momilactone B in rice seedlings but also secretion of momilactone B into rice rhizosphere. As momilactone B acts as an antimicrobial and allelopathic agent, secretion of momilactone B into the rhizosphere may provide a competitive advantage for root establishment through local suppression of soil microorganism and inhibition of the growth of competing plant species.

Mapping-guided ablation of the cavotricuspid isthmus: a novel simplified approach to radiofrequency catheter ablation of isthmus-dependent atrial flutter.

BACKGROUND: Because the anatomic features of the cavotricuspid isthmus (CTI) are complex, radiofrequency (RF) energy requirements for CTI ablation may vary at each point within the CTI. Conventionally, multiple-site mapping has been required for determining CTI conduction block. OBJECTIVES: The purpose of this study was to develop a more efficacious method for ablation of isthmus-dependent atrial flutter. METHODS: Forty consecutive patients underwent CTI ablation using a CTI mapping-guided approach (20 patients) or a conventional approach (20 patients). In the CTI mapping-guided approach, an octapolar catheter was positioned on the CTI parallel to, and downstream from, the intended ablation line in order to map and ablate the breakthrough point. RESULTS: Complete CTI block was achieved in all study patients. CTI mapping of incomplete ablation lines revealed that the site with the shortest interval between double potentials did not always coincide with the conduction gap. Disappearance of a breakthrough pattern on the CTI electrograms corresponded to creation of complete CTI block. During ablation, CTI mapping exhibited pseudo-CTI block in 8% of patients in the clockwise direction and 63% of patients in the counterclockwise direction. The number and total time of RF applications were significantly lower with the CTI mapping-guided approach than with the conventional approach (7.7 +/- 3.9 applications vs 13.8 +/- 8.9 applications and 8.9 +/- 4.4 minutes vs 16.3 +/- 11.9 minutes, respectively, P <.05). In the CTI mapping-guided approach, RF applications were not required along the entire CTI in 7 patients (35%). CONCLUSION: This simplified technique was feasible for creating and determining complete CTI block, with fewer RF applications required.

Concentration and release level of momilactone B in the seedlings of eight rice cultivars.

The release levels of a growth inhibitor, momilactone B, from rice (Oryza sativa L.) seedlings of eight cultivars were compared with the endogenous concentrations of momilactone B in their seedlings. All rice cultivars contained momilactone B in the seedlings, and their concentrations differed between the cultivars. Momilactone B was also found in all culture solutions in which these rice seedlings were grown, and the concentrations differed between the cultivars. The momilactone B concentrations in the culture solutions were reflected in the momilactone B concentrations in the seedlings. These results suggest that all rice cultivars may produce momilactone B and release momilactone B into the culture solutions. In addition, the release level of momilactone B may depend on the production level of momilactone B in the seedlings, which may affect allelopathic potential of these rice cultivars because as a growth inhibitor, momilactone B is able to act as an allelochemical.

Possible involvement of momilactone B in rice allelopathy.

Since residues and extracts of rice plants were known to inhibit the germination and growth of several plant species, the possible involvement of a growth inhibitor, momilactone B, in rice allelopathy was discussed. Momilactone B was found in shoots and roots of rice plants over their entire life cycle. The level of momilactone B in shoots and roots increased with rice plant growing until flowering initiation, and then decreased. The highest level of momilactone B in the shoots and roots at the day of flowering initiation was 245 and 64.1 nmol g(-1) fresh weight, respectively. Thus, 1 kg of rice shoots and roots, respectively, may be able to release 245 and 64.1 micromol of momilactone B into the soil or neighboring environment by decomposition of their residues, which may be sufficient to cause growth inhibition of their neighboring or successional plants. The growth inhibitory activity of momilactone B and the occurrence of momilactone B in rice plants suggest that momilactone B may contribute the growth inhibitory effect of rice residues and extracts, indicating that momilactone B may have an important role in the rice allelopathy.

A case of massive left atrial lipoma occupying pericardial space.

We report a rare case of massive left atrial lipoma occupying pericardial space. A 52-year-old male was admitted because of cardiomegaly of unknown etiology. Computed tomography showed a large epicardial mass located along the anterior surface of the heart, from the diaphragm level through the aortic arch level. The mass showed an attenuation value identical with that of subcutaneous adipose tissue and contained some areas with high density. The mass was not enhanced by contrast media. Histologic examination of the specimen obtained by percutaneous biopsy demonstrated mature adipose tissue. An encapsulated adipose mass weighing 620 g, which originated from the left atrium without any invasion to the pericardium, was completely excised. Microscopic examination revealed mature adipose tissue with partial necrosis, confirming the diagnosis of lipoma.

Pseudotermination of atrioventricular nodal reentrant tachycardia related to isorhythmic atrioventricular dissociation.

Unusual manifestations of the mode of termination were observed in a patient with atrioventricular nodal reentrant tachycardia (AVNRT). After administration of verapamil during AVNRT, isorhythmic atrioventricular dissociation occurred without termination of the tachycardia. The sinus rate was slightly faster than that of the AVNRT, leading to the P wave preceding the QRS complex with a normal PR interval (e.g., pseudotermination). This phenomenon emphasizes the importance of continuous monitoring during an attempt to terminate AVNRT.

Rice seedlings release momilactone B into the environment.

Since the growth inhibitor momilactone B was found recently in root exudates of rice (Oryza sativa L.), 3-day-old rice seedlings were transferred to hydroponic culture and the level of momilactone B released into the environment from the seedlings was measured. At day 15 after transfer, the level of momilactone B in the culture solution was 1.8 nmol per seedling compared with endogenous levels of 0.32 and 0.63 nmol per root and shoot, respectively, suggesting that rice seedlings actively releases momilactone B into the culture solution. This release must occur from the roots because only rice roots were immersed in the culture solution. Momilactone B inhibited the growth of ten cress (Lepidium sativum L.) seedlings at concentrations greater than 3 microM. Ten rice seedlings were incubated with ten cress seeds in a Petri dish containing 1 ml of medium, the medium contained 18 nmol of momilactone B, which came to 18 microM. This level of momilactone B was enough to reveal growth inhibition of the cress seedlings. Release level of momilactone B and its effectiveness as a growth inhibitor suggest that it may play an important role in rice allelopathy.

[Use of YAG laser combined with mucosal suturing for the treatment of polypoid vocal cord].

To improve low-pitched voices in cases with polypoid vocal cords, YAG laser irradiation combined with a mucosal suturing technique was attempted in 9 female cases with severe polypoid changes in their vocal cords. A YAG laser beam (5 to 10 W) was used to irradiate the upper surface of the polypoid vocal cord. The polypoid content of the cord was gradually coagulated, and the free edge of the cord appeared to slide up toward the burned area. The polypoid content was then removed and squeezed through an open wound made in the burned area using a conventional method. Bleeding was successfully controlled using the laser. After the excessive mucosal margin was trimmed and the contour of the vocal cord was adjusted, the wound was closed by 7-0 monofilament absorbable suture. Suturing was relatively easy because the mucosal edge was also coagulated. Postoperative evaluations of voice quality revealed an improvement in the GRBAS scale of voice quality as well as an elevation in voice pitch and an upwards shift in the voice range in all cases.

Characteristics of the electrical activity within the persistent left superior vena cava: comparative view with reference to the ligament of Marshall.

We sought to characterize the electrical activity within the persistent left superior vena cava (LSVC), which normally becomes the ligament of Marshall (LOM) that is known to be related to the genesis of atrial tachyarrhythmias. A 20-pole electrode catheter was used to record the entire activation sequence in the LSVC in a patient with Wolff-Parkinson-White syndrome. Electrical activity representing the musculature of the LSVC could be recorded up to a level as high as the pulmonary artery. Multiple electrical connections between the LSVC and left atrium were shown, and one of the connections exhibited unidirectional conduction block. It might be important to take into account the presence of multiple electrical connections when we consider the LOM as a target for radiofrequency catheter ablation or its role in clinical arrhythmias.

Changes in release level of momilactone B into the environment from rice throughout its life cycle.

Momilactone B was released into the neighboring environment from rice throughout its life cycle. The rate of momilactone B release from rice increased until flowering initiation, and then decreased. The release rate of momilactone B at the day of flowering started was 2.1 µg plant-1 d-1. On average, a single rice plant released about 100 µg of momilactone B into the neighboring environment over its life cycle. Since momilactone B is a growth inhibitor, these results suggest that momilactone B released from rice plants may serve as an allelochemical to inhibit the germination and growth of neighboring plants.

Isolation and identification of a potent allelopathic substance in rice root exudates.

A search for growth inhibitors in rice root exudates was undertaken in order to clarify the allelopathic system in rice (Oryza sativa L.). Rice seedlings inhibited the growth of cress (Lepidium sativum L.) and lettuce (Lactuca sativa L.) seedlings when the cress and lettuce were grown with rice seedlings. The putative compound causing the inhibitory effect of rice seedlings was isolated from their culture solution, and the chemical structure of the inhibitor was determined by spectral data as momilactone B. Momilactone B inhibited the growth of cress and lettuce seedlings at concentrations greater than 3 and 30 microM, respectively. The concentration of momilactone B was 3.4 and 1.1 nmol per seedling in the culture solutions of husked and non-husked rice seedlings, respectively. These results suggest that rice seedlings may release momilactone B into the environment and the stress caused by the husk-treatment may increase the amount of momilactone B released. Thus, momilactone B may play an important role in rice allelopathy.