Fractional Exhaled Nitric Oxide (FeNO) and Spirometry as Indicators of Inhalation Exposure to Chemical Agents in Pathology Workers.

OBJECTIVE: The objective of this study was to examine whether fractional exhaled nitric oxide (FeNO) and spirometry can be used as indices to evaluate adverse health effects of low-concentrated chemical inhalation exposure, mainly to formaldehyde. METHODS: Thirty-three subjects (pathology technicians) and 30 controls (workers without handling any chemicals in the same hospitals) participated in this study. All participants underwent FeNO measurement and spirometry before and after 5 days of work. RESULTS: FeNO significantly increased in the subjects with a history of asthma (P < 0.05), whereas forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1) decreased in the subjects (P < 0.05). Furthermore, work duration and pre-work levels of FEV1 in the subjects had a significant association. CONCLUSION: The results suggest that FeNO, FVC, and FEV1 represent effective health-effect indices of low-concentrated chemical inhalation exposure.

Relationship between sleep bruxism and sleep respiratory events in patients with obstructive sleep apnea syndrome.

PURPOSE: Both obstructive sleep apnea syndrome (OSAS) and sleep bruxism (SB) are commonly related to arousal events. In this study, we examined the effect of SB on the sleep architecture and investigated the relationship between SB and sleep respiratory events in patients with OSAS. METHODS: Patients with OSAS (n=67) in whom apnea/hypopnea occurred five or more times per hour were recruited to this study. Healthy volunteers (n=16) were recruited as controls. None of the healthy volunteers had any sleep disorders or medical disorders, nor had they taken any medication or alcohol. Data were collected by standard polysomnography during overnight sleep tests in a dark, quiet room. RESULTS: The frequency of SB was higher in the OSAS than in the control group. The risk of SB was significantly higher in the OSAS than in the control group (odds ratio, 3.96; 95% confidence interval, 1.03-15.20; P<0.05). Apnea/hypopnea and desaturation events occurred significantly more frequently in patients with than without SB. The frequency of the phasic type of SB correlated positively with that of obstructive apnea, micro-arousal, and oxygen desaturation. The frequency of SB events during micro-arousal events consequent on apnea/hypopnea events was significantly higher in the OSAS than in the control group. CONCLUSIONS: We found that patients with OSAS have a high risk of SB. In particular, this is the first report relating phasic-type SB to obstructive apnea events. This relationship suggests that improvement in OSAS might prevent exacerbations of SB.

A novel EEG index for evaluating the sleep quality in patients with obstructive sleep apnea-hypopnea syndrome.

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a highly prevalent sleep disorder characterized by recurrent episodes of oxygen desaturation during sleep, decreased sleep quality, and excessive daytime sleepiness. A basic method of evaluating sleep quality is polysomnography (PSG) where sleep stages are identified from the electroencephalogram (EEG), electrooculogram and chin electromyogram. The implementation of PSG is limited to sleep laboratories because this test is rather complicated to perform and quite time-consuming to analysis, requiring skilled technicians. Development of simple alternative methods to PSG could enable sleep tests to be performed at home. Our study aimed to identify simple measures for evaluating the sleep quality. We focused on a simple index, entropy, which is derived from power spectrum of EEG signals throughout the night, and reflects the dynamics of EEG signals, and examined whether the entropy of EEG reflects the sleep quality of OSAHS. The EEG signals for the analysis of EEG entropy were recorded from the temple area. The EEG entropy was compared with the sleep quality by traditional approaches of EEG from PSG in 58 OSAHS patients and 8 healthy volunteers. The EEG entropy in each subject showed the negative values and fluctuated during sleep. There was a significant correlation between the EEG entropy and the sleep quality (r = 0.626, p < 0.001); namely, the amplitude of the fluctuation was increased with the increase in the sleep quality. We therefore propose that the EEG entropy could be useful for evaluating the sleep quality of OSAHS.

[Examination of spirometry techniques on instruction by medical technologists for screening purposes].

BACKGROUND: The burden of chronic obstructive pulmonary disease (COPD) remains very high. Current consensus guidelines emphasize the importance of the early detection of COPD, but its underdiagnosis is common in general practice. Spirometry is the "gold standard" in the diagnosis of COPD. However, it remains underused in general practice because the application of spirometry is viewed as difficult to obtain accurate results. AIMS: To clarify the accuracy of spirometry techniques for screening purposes. METHOD: Subjects (n = 142) were told about the spirometry procedure using pre-determined descriptions, followed by the first spirometry test. Special medical technologists gave instructions on the detailed spirometry procedure on reference to the first test of results, and the second spirometry test was performed. The second spirometric indices, SVC, FVC, FEV1, FEV1%, and PEF, were compared with the first ones. RESULTS: The instruction by special medical technologists significantly improved all spirometric indices except for FEV1%. For a diagnosis of restrictive disorder (VC<80%), the impact of intervention by the special medical technologists was highly significant (p<0.001). In contrast, for the diagnosis of obstructive disorder (FEV1%<70%), the impact was small. CONCLUSION: To detect obstructive disorder, the high-level accuracy of special spirometry techniques is not always necessary.

[Evaluation of a simplified index (spectral entropy) about sleep state of electrocardiogram recorded by a simplified polygraph, MemCalc-Makin2].

BACKGROUND: Polysomnography (PSG) is the gold standard for the diagnosis of sleep apnea hypopnea syndrome (SAHS), but it takes time to analyze the PSG and PSG cannot be performed repeatedly because of efforts and costs. Therefore, simplified sleep respiratory disorder indices in which are reflected the PSG results are needed. The Memcalc method, which is a combination of the maximum entropy method for spectral analysis and the non-linear least squares method for fitting analysis (Makin2, Suwa Trust, Tokyo, Japan) has recently been developed. Spectral entropy which is derived by the Memcalc method might be useful to expressing the trend of time-series behavior. AIM: Spectral entropy of ECG which is calculated with the Memcalc method was evaluated by comparing to the PSG results. SUBJECTS: Obstructive SAS patients (n = 79) and control volanteer (n = 7) METHODS: ECG was recorded using MemCalc-Makin2 (GMS) with PSG recording using Alice IV (Respironics) from 20:00 to 6:00. Spectral entropy of ECG, which was calculated every 2 seconds using the Memcalc method, was compared to sleep stages which were analyzed manually from PSG recordings. RESULTS: Spectral entropy value (-0.473 vs. -0.418, p < 0.05) were significantly increased in the OSAHS compared to the control. For the entropy cutoff level of -0.423, sensitivity and specificity for OSAHS were 86.1% and 71.4%, respectively, resulting in a receiver operating characteristic with an area under the curve of 0.837. The absolute value of entropy had inverse correlation with stage 3. CONCLUSIONS: Spectral entropy, which was calculated with Memcalc method, might be a possible index evaluating the quality of sleep.

[Effect of age on electrocardiogram entropy value of parameters by sleep respiratory disturbance].

BACKGROUND: Spectral entropy of electrocardiogram (ECG), which was calculated using the MemCalc method with a portable bio-signal measurement instrument (PBSM), might be a possible parameter for evaluating the quality of sleep. AIM: This study assessed the effects of ECG spectral entropy on obstructive sleep apnea/hypopnea syndrome (OSAHS) depending on age. STUDY DESIGN: ECG was recorded using a PBSM, and the maximum entropy of ECG every 9 RR intervals was calculated. These entropies were compared with the age and sleeping indices obtained with a conventional polysomnography (PSG) system. SETTING AND PARTICIPANTS: Seventy-six patients suspected of OSAHS were recorded from 20:00 to 06:00 using a conventional PSG system (Alice III) and a PBSM (MemCalc-Makin2) simultaneously. RESULTS: ECG entropy showed correlations to high frequency (HF, 0.15-0.40 Hz) heart rate variability in the cardiac parasympathetic activity index, as did the ECG entropy value, and a negative correlation was found with the age (r = 0.538, p < 0.0001), and positive correlation with the HF value (r = 0.810, p < 0.0001). The ECG entropy value in subjects aged > or = 40 with no different sleep respiratory disturbance index by PSG data (AHI, Arousal Index, DSI, and sleep efficiency, etc.) to 60 years old was compared with those aged > or = 60. The ECG entropy value and HF value decreased at > or = 60 years old with statistically significant. CONCLUSION: The value of ECG entropy corresponds to cardiac parasympathetic function, and it decreases according to age (increase by the absolute value).

[Staging of sleep based on electroencephalograms and mental electromyograms recorded by a simplified polygraph, MemCalc-Malkin2].

OBJECTIVE: To examine the feasibility of MemCalc-Malkin2, a simplified polygraph, for staging of sleep. DESIGN: Electroencephalograms and mentalelectromyograms were recorded in 33 patients with possible obstructive sleep apnea-hypopnea syndrome by a simplified polygraph, MemCalc-Malkin2, and their frequencies were analyzed according to the sleep stage that were determined by a simultaneous conventional polysomnography. RESULTS: Sleep was divided into four stages, i.e., awake(SWake), rapid eye movement phase(SREM), shallow non-REM sleep {S(1+2)}, and deep non-REM sleep {S(3+4)}. The ratio of the amount of beta waves to that of delta waves was significantly different between the four sleep stages (p < 0.05), being highest in SWake and lowest in S(3+4). Mental electromyographic discharges were significantly more active in SWake and S(1+2) than in S(3+4) and SREM. CONCLUSION: A MemCalc-Malkin2 appears promising for staging of sleep.

A comparison of urinary albumin-total protein ratio to phase-contrast microscopic examination of urine sediment for differentiating glomerular and nonglomerular bleeding.

BACKGROUND: Hematuria can be classified as either glomerular or nonglomerular, depending on the bleeding source. We recently reported that urinary albumin-total protein ratio is potentially useful for identifying the source of hematuria. STUDY DESIGN: Diagnostic test study. SETTING & PARTICIPANTS: 579 fresh urine specimens with microhematuria (> or =5 red blood cells/high-power field) collected from patients with the source of the hematuria confirmed on histopathologic and/or imaging studies and clinical criteria assessed. INDEX TEST: Each urine specimen was evaluated morphologically by using phase-contrast microscopy and biochemically by using urinary albumin-total protein ratio, albumin-creatinine ratio, and total protein-creatinine ratio. REFERENCE TEST: Each patient had a definitive clinical diagnosis established by means of biopsy (64.4%), imaging studies (21.2%), and routine optimal microscopic examination of urine sediment (14.3%). RESULTS: Of 579 specimens, 329 were obtained from patients with glomerular disease and 250 were obtained from patients with nonglomerular disease. Mean urinary albumin-total protein, albumin-creatinine, and total protein-creatinine ratios for those with glomerular versus nonglomerular diseases were 0.73 +/- 0.11 versus 0.41 +/- 0.14 mg/mg (P < 0.001), 1,110 +/- 1,850 versus 220 +/- 560 mg/g (P < 0.001), and 1,600 +/- 3,010 versus 480 +/- 1,160 mg/g (P < 0.001), respectively. The percentage of patients with greater than 3% glomerular red cells was 83.3% versus 24.8% (P < 0.001). Receiver operating characteristic curve analysis showed that areas under the curve for albumin-total protein ratio, albumin-creatinine ratio, and total protein-creatinine ratio were 0.992, 0.781, and 0.688, respectively (P < 0.001, albumin-total protein versus albumin-creatinine; P < 0.001, albumin-total protein versus total protein-creatinine). At cutoff values of 0.59 mg/mg, 71 mg/g, and 265 mg/g, albumin-total protein ratio, albumin-creatinine ratio, and total protein-creatinine ratio had sensitivities and specificities of 97.3% and 100%, 78.9% and 61.1%, and 68.8% and 62.0% for detecting glomerular disease, respectively. Phase-contrast microscopy had sensitivity of 83.3% and specificity of 75.2% for detecting glomerular disease. LIMITATIONS: Albumin-total protein ratio cannot be used in patients with urinary total protein less than 5 mg/dL (<0.05 g/L). Use of only 1 sample from 1 patient may not be sufficient to obtain definitive results. CONCLUSIONS: Urinary albumin-total protein ratio is much more useful than phase-contrast microscopy for differentiating between glomerular and nonglomerular disease in patients with microscopic hematuria.

Evaluation of hematuria using the urinary albumin-to-total-protein ratio to differentiate glomerular and nonglomerular bleeding.

BACKGROUND: Depending on the etiology and pathophysiology of hematuria, urinary bleeding is classified as glomerular hematuria or nonglomerular hematuria. Nephritis is usually detected by the presence of proteinuria, especially elevated albumin excretion. In this study, we report on the use of the urinary albumin-to-total-protein ratio to accurately differentiate glomerular and nonglomerular bleeding. METHODS: A total of 143 fresh, random urine specimens demonstrating microscopic hematuria (5 or more red blood cells per high-power field) from patients with the source of the hematuria confirmed by histopathology and/or clinical criteria were included in the study. RESULTS: Of the 143 specimens, 104 were from patients diagnosed with glomerular disease and 39 were from patients with nonglomerular disease. Corrected for urine concentration, the mean total-protein-to-creatinine (Cr) and albumin-to-Cr ratios in the glomerular disease group were 1.67 +/- 2.71 g/g Cr and 1.15 +/- 1.77 g/g Cr, respectively (P < 0.001). In the nonglomerular group, the mean total protein-to-Cr and albumin-to-Cr ratios were 0.19 +/- 0.23 g/g Cr and 0.05 +/- 0.06 g/g Cr, respectively (P < 0.001). However, considerable overlap in the ratios among glomerular and nonglomerular disease groups was observed. In contrast, the mean albumin-to-total protein ratios for glomerular and nonglomerular diseases were 0.72 +/- 0.10 and 0.35 +/- 0.17, respectively (P < 0.001). At a cutoff of 0.59, the albumin-to-total-protein ratio demonstrated a sensitivity of 97.1% (101 of 104 cases) in detecting glomerular disease. CONCLUSIONS: The urinary albumin-to-total-protein ratio is potentially a useful index for the differentiation of glomerular and nonglomerular disease in the presence of microscopic hematuria.

[Significance of urine dipstick test for occult blood in patients with diabetes mellitus].

OBJECTIVE: Hematuria is the usual urinary finding in patients with diabetic nephropathy. In this study, prevalence and significance of microhematuria in patients with diabetes mellitus were investigated. MATERIAL AND METHODS: Five hundred and forty-two samples from outpatients, who consulted the Department of Diabetes and Metabolism, were categorized into 4 groups according to the results of the urine dipstick test. Group I :258 samples, urinary protein(u-P) 1+ and occult blood (OB) negative, group II: 95 samples: u-P 1+, OB 1+ approximately 3+, group III: 89 samples: u-P 2+ approximately 3+, OB negative, group IV 100 samples u-P 2+ approximately 3+, OB 1+ approximately 3+. RESULTS: Serum concentrations of creatinine and highly sensitive CRP were both significantly higher in group II than in group I . Those parameters were also significantly higher in group IV than in group III. CONCLUSIONS: These results indicate that a positive dipstick test for OB may occur in many patients with diabetes mellitus and suggest the progress of renal damage.

[Comparison between optical microscopic examination and phase contrast microscopic examination for diagnosing the origin of urinary bleeding].

PURPOSE: Phase contrast microscopy method is useful in the examination of urine sediment to differentiate glomerular(Gl) hematuria from non glomerular(nonGl) hematuria. In this study, we compared the diagnostic value of optical microscopy with that of phase contrast microscopy. METHOD: One hundred and sixty fresh urine samples of microscopic hematuria(5/HPF or more) from 118 patients with renal disease and 42 patients with urologic disease were analyzed. The erythrocytes referred to as Gl, are defined to have acanthocytes, target configuration, or finger ring shape, and a Gl cell/total erythrocyte ratio greater than 3% is defined as reliable marker for Gl bleeding. RESULT: Sensitivity and specificity of this criteria for Gl bleeding were 50.9% and 94.9% in acanthocytes, 69.6% and 89.1% in the target configuration, and 88.4% and 89.1% in the finger ring, respectively. As for the microscopic observation methods, the sensitivity and specificity of this criteria for GI bleeding were 88.1% and 81.0% with phase contrast microscopy, 74.6% and 90.9% with optical microscopy with no dyeing, and 74.6% and 88.6% with optical microscopy with dyeing, respectively. CONCLUSION: GI and nonGl hematuria were correctly diagnosed by counting the urinary Gl cells not only by phase contrast microscopy, but also by optical microscopy. This method seems to have important clinical usefulness by offering information on urinary bleeding.

[The relationship of autonomic functional disturbance and atherosclerosis in type 2 diabetes].

The aim of the study was to assess the relationship between the autonomic nerve disturbance and atherosclerotic changes in patients with type 2 diabetes. Aortic distensibility and max carotid intima-media thickness (Max IMT) were evaluated using brachial ankle pulse wave velocity (PWV) and high-resolution B-mode ultrasonography, respectively, in 135 patients (69 men, 66 women, 57 +/- 16 years) with type 2 diabetes. The autonomic neuropathy was evaluated using coefficient of variation of the RR interval (CV(R-R)) of electrocardiograms recorded at rest in a supine position. There was a significant negative correlation between CV(R-R)and Max IMT (r= -0.488, p< 0001). There were also significant negative correlations between CVR-(R a)nd the left and the right PWV(r=0.518, p<0.001; r=0.551, p<0.001, respectively). Patients with normal Max IMT, but decreased CVR-R, had a high PWV compared to patients with normal Max IMT and normal CVR-(R. )Therefore, decreased CVR-(R i)n type 2 diabetic patients may reflect atherosclerotic changes. Thus, the measurement of CVR-(R i)s a simple and quantitative test for assessing atherosclerotic as well as neuropathic complications in diabetic patients.

[The relationships between autonomic function and heart rate in essential hypertension].

The circadian variation of blood pressure (BP) may be mediated at least in part by circadian variation of autonomic nervous system activity. In the present study power spectral analysis of hourly R-R intervals for 24 hours was done to obtain the low frequency variability (LF: 0.04 to 0.15Hz) and high frequency variability(HF: 0.15 to 0.40Hz) in 93 patients with untreated essential hypertension. LF/HF ratio and HF were considered to be an index of sympathetic nervous activity and parasympathetic nervous activity, respectively. The relationship between heart rate (HR) and systolic blood pressure (SBP), diastolic blood pressure (DBP), HF, and LF/HF was examined. Both SBP and DBP were correlated positively with HR(r = 0.28, p < 0.05 and r = 0.27, p < 0.05, respectively) in the daytime. HF was correlated negatively and significantly with HR in both daytime and nighttime (r = -0.40, p < 0.05, and r = -0.38, p < 0.05 respectively). After averaging for SBP of 24 hours, HR in the patients whose SBP was 135mmHg or more was significantly higher than that in the patients whose SBP was less than 135mmHg. These results suggest that the decreased parasympathetic nervous activity seems to be responsible for the rise in BP.

[The Autonomic Nervous Activity in Patients with Essential Hypertension who Showed Early Morning Rise of Blood Pressure].

Autonomic nervous function was evaluated by means of power spectral analysis of heart rate variability in patients with essential hypertension who showed early morning rise of blood pressure (BP). We monitored ambulatory (BP) and physical activity in 80 untreated patients using TM 2425 (A&D Co.Ltd.). Early morning rise of BP was defined a patient's blood pressure obtained between 6:00 to 9:00am is 170mmHg or higher. Patients who showed early morning rise of BP were categorized into groups. Twenty patients, whose mean BP obtained between 6:00 to 9:00am were higher than those obtained between 3:00 to 600am by 30mmHg or more, were defined as a surge type. Sixty patients, in whom the difference in BP was less than 30mmHg, were defined as a sustained type. Power spectral analysis of hourly R-R intervals for 24 hours was performed to obtain the low frequency power (LF, 0.04 to 0.15 Hz) and high frequency power (HF, 0.15 to0.04 Hz). LFn and LF/HF ratio were considered to be indexes of sympathetic nervous activity, and HF parasympathetic nervous activity, respectively. Between 3:00 to 6:00am, LFn and LF/HF were significantly higher and HF was significantly lower in the sustained type patients than in the surge type patients. LF/HF and LFn in the surge type elevated significantly beween 6:00 to 9:00am. These results indicate that both the loss of nocturnal decline in BP in the sustained type and the morning rise in BP in the surge type to occurred in association with changes in autonomic nervous system.

[The autonomic nervous activity of hypertension].

Autonomic nervous function was evaluated by means of power spectral analysis of heart rate variability in hospitalized patients with different circadian blood pressure(BP) variation, i.e., dipper(n = 33), non-dipper(n = 37), extreme dipper(n = 26) and riser(n = 20). Ambulatory BP monitoring was performed by A & D TM2425 based on a cuff-oscillometric method. Circadian BP variation was defined in these subjects. The non-dipper, extreme dipper and riser subjects were defined as those whose nocturnal decrease in systolic BP was less than 10%, more than 20% and elevation of BP, as compared to the daytime BP, respectively. Power spectral analysis of hourly R-R intervals for 24 hours was done to obtain the low frequency power(LF, 0.04 to 0.15 Hz) and high frequency power(HF, 0.15 to 0.40 Hz). LF/HF ratio was considered to be an index of sympathetic nervous activity, and HF parasympathetic nervous activity, respectively. LF/HF was significantly lower in both riser and non-dipper than that in dipper subjects throughout the day. In non-dipper day-night difference of HF was smaller than in dipper and extreme dipper groups. These findings indicated that riser and non-dipper hypertensives were characterized by decreased physiological circadian fluctuation of autonomic functions when compared to dipper subjects. The circadian variation of BP may be mediated at least in part by circadian variation of autonomic nervous system activity.

[Comparative study of T-wave alternans, QT c dispersion and late potential for predicting ventricular tachycardia in patients with ischemic heart disease].

Ventricular tachycardia(VT) is well known as the life-threatening arrhythmia. It would be important for predicting the risk of VT to prevent sudden death caused by VT after myocardial damage such as old myocardial infarction and dilated cardiomyopathy. In this study, we examined late potential(LP), TWA alternans(TWA), and QTc dispersion(QTcd) measured by Holter ECG, in 21 patients with old myocardial infarction(OMI) and 21 patients with dilated cardiomyopathy(DCM), and evaluated these parameters in relation with the occurrence of VT on these patients. The sensitivities of LP, TWA, and QTcd in patients with OMI in relation with VT were 82%, 73%, and 82%, respectively, and those in patients with DCM were 82%, 93%, and 73%, respectively. The specificities of LP, TWA, and QTcd in patients with OMI in relation with VT were 100%, 40%, and 100%, respectively, and those in patients with DCM were 100%, 30%, and 100%, respectively. The data demonstrated that LP and TWA were the useful predictive parameters for the VT on myocardial damage such as OMI and DCM.