Ameliorative effect of traditional Chinese medicine prescriptions on alpha-naphthylisothiocyanate and carbon-tetrachloride induced toxicity in rats

Syh-Mo-Yin (SMY), Guizhi-Fuling-Wan (GFW), Shieh-Qing-Wan (SQW) and Syh-Nih-San (SNS) are prescriptions of Traditional Chinese Medicine (TCM) for liver disease. The effects of these four prescriptions against experimental liver injury induced by alpha-Naphthylisothiocyanate (ANIT) and carbon tetrachloride (CCl4) were studied. Rats treated with ANIT (100 mg/kg) exhibited elevations of serum total bilirubin (TBI), alkaline phosphatase (ALP), glutamate-oxalatetransaminase (sGOT) and glutamate-pyruvate-transminase (sGPT) as well as cholestasis and parenchymanecrosis. In rats receiving SMY, SQW and SNS treatment after ANIT challenged, the biochemical and morphological parameters of liver injury were significantly reduce. Elevated lipid peroxidation (LPO) level in liver tissue, associated with an increase in serum GOT and GPT level, was observed in CCl4-treated rats. Treatment with these four prescriptions on CCl4-induced liver injury rats showed a remarkable hepatoprotective effect. A significant decrease in peroxidative level suggested that these prescriptions have anti free radical properties.

A study of the relationship between ambient lead and blood lead among lead battery workers

OBJECTIVE

To examine the relationship between ambient lead levels and blood lead levels and to explore the modifiers of the relationship between ambient lead and blood lead.

METHOD

A cross-sectional study was conducted in two lead battery factories. Blood lead level and ambient lead concentration were measured for each participant concurrently. A structured questionnaire was administered to collect sociodemographic characteristics and occupational history.

DESIGN

Biological and personal environmental measurements of 219 lead-exposed workers were analyzed by both simple and multiple linear regression. A regression model was selected for interpretation.

RESULTS

A high correlation (r = 0.62) between ambient lead (PbA) and blood lead (PbB) was observed. In addition, numerous factors, including age, sex, alcohol consumption, personal hygiene practice and type of lead exposure, were also found to influence blood lead levels. Although PbB was highly correlated with PbA, blood lead level may not be effectively lowered by reducing ambient lead level. Based on the regression coefficients, improvement of hygienic practice was more effective at lowering PbB than reducing ambient lead level. Good hygienic practice may be the preferential way to reduce lead exposure in current conditions.

CONCLUSION

Education of correct work practice may be more important than engineering control in the developing countries to lower blood lead levels in lead battery factories.

Effects of exposure to carbon disulfide (CS2) on electrocardiographic features of ischemic heart disease among viscose rayon factory workers

The objective of the study was to evaluate viscose plant workers for electrocardiographic manifestations resulting from exposure to carbon disulfide (CS2). A total of 162 workers (118 in an exposure group and 44 in a reference group) were evaluated using a health questionnaire, physical check-up, biochemical analysis of blood samples and electrocardiograms (ECG). The exposure group consisted of workers in the following areas: viscose manufacturing, cellophane processing, ripening, and filament spinning. Reference group workers were from the administrative office, rolling area, pulp processing, and testing office. Only slight differences were found in the biochemical analyses of the two groups, with the exception of sodium (Na) levels. Personal and area sampling results were found to have a high variation due to different locations within the plant and a wide range of manufacturing processes. Highest CS2 concentrations were found in the ripening area (54.60 ppm) and the filament spinning area (19.60 ppm). Using a multiple logistic regression model to control variables (age, gender, body mass index, duration of employment, cholesterol, smoking, and alcohol), we found a relative risk for ECG abnormalities 4.18 times significantly higher for the exposure group. The authors feel that the installation of an adequate ventilation system could greatly reduce the risk of workers developing CS2-induced cardiovascular abnormalities.

In vitro V(D)J recombination: signal joint formation

The first step of V(D)J recombination, specific cleavage at the recombination signal sequence (RSS), can be carried out by the recombination activating proteins RAG1 and RAG2. In vivo, the cleaved coding and signal ends must be rejoined to generate functional antigen receptors and maintain chromosomal integrity. We have investigated signal joint formation using deletion and inversion substrates in a cell free system. RAG1 and RAG2 alone or in combination were unable to generate signal joints. However, RAG1 and RAG2 complemented with nuclear extracts were able to recombine an extrachromosomal substrate and form precise signal joints. The in vitro reaction resembled authentic V(D)J recombination in being Ku-antigen-dependent.

Establishment of a work-related diseases surveillance system in Taiwan, Republic of China

BACKGROUND

The occurrence of occupational illness and injury has been seriously underestimated in Taiwan, which subsequently contributes to difficulties in performing effective control of occupational hazards and implementing intervention programs for protecting workers.

METHODS

Based on the successful experience of the nationwide blood lead level surveillance program, the Department of Health, the Executive Yuan, Taiwan, Republic of China, has established a work-related diseases surveillance system. This government-administered system requests practicing physicians to report the suspected cases suffering from six categories of work-related disorders.

RESULTS

An occupational illness and injury surveillance program in Taiwan has been in operation since June of 1995.

CONCLUSION

Background information of work-related diseases obtained from this surveillance system will be useful for providing better management of available resources for occupational medicine, for preventing hazards, and for enforcing occupational diseases prevention programs. Our experience in establishing this surveillance system will be used in other countries and settings.

The practice of Chinese medicine in Taiwan

This paper examines the practice of Chinese medicine in Taiwan. Using a national sample survey of Chinese medicine physicians, supplemented by another national survey of Chinese medicine hospitals and government records, the authors study the education and training background of Chinese medicine physicians, their mode of practice, their productivity measured by patient visits, and the practice characteristics of Chinese medicine hospitals. Moreover, the authors investigate the relationship between the resource input, the public health insurance contract, and the number of patient visits Chinese medicine physicians provided. Results of this study are used to make several recommendations on the appropriate way of integrating the practice of Chinese medicine into the modern health care system. Many of these recommendations may also be applicable to other countries that are contemplating integrating traditional or alternative medicine into their health care systems.

Real-time implementation of electromyogram pattern recognition as a control command of man-machine interface

The purpose of this study was to develop a real-time electromyogram (EMG) discrimination system to provide control commands for man-machine interface applications. A host computer with a plug-in data acquisition and processing board containing a TMS320 C31 floating-point digital signal processor was used to attain real-time EMG classification. Two-channel EMG signals were collected by two pairs of surface electrodes located bilaterally between the sternocleidomastoid and the upper trapezius. Five motions of the neck and shoulders were discriminated for each subject. The zero-crossing rate was employed to detect the onset of muscle contraction. The cepstral coefficients, derived from autoregressive coefficients and estimated by a recursive least square algorithm, were used as the recognition features. These features were then discriminated using a modified maximum likelihood distance classifier. The total response time of this EMG discrimination system was achieved about within 0.17 s. Four able bodied and two C5/6 quadriplegic subjects took part in the experiment, and achieved 95% mean recognition rate in discrimination between the five specific motions. The response time and the reliability of recognition indicate that this system has the potential to discriminate body motions for man-machine interface applications.

Use of REMEDi HS in emergency toxicology for a rapid estimate of drug concentrations in urine, serum, and gastric samples

The REMEDi HS is a broad spectrum drug identification system, designed for emergency toxicology screening and forensic applications. The total analysis time is about 20 min. The current library has 555 drugs and metabolites. The system has a software routine that uses an internal standard (IS) to perform quantitative analysis for target compounds when calibrators are available; further, response factors (RF) are supplied for a rapid estimate of drug concentrations when calibrators are unavailable. In the present study, The concentrations of six drugs (bromisovalum, ephedrine, hydroxyzine, diphenhydramine, ranitidine, and lidocaine) and a metabolite of lidocaine (glycinexylidide) were determined using both methods. The slopes of the regression lines between the rapid estimate method and the IS method were generally within 20% of unity, in agreement with the manufacturer's claim. Semiquantitative estimates based on RF also showed good agreement with results obtained using multipoint calibration. These estimates were sufficient for clinical differentiation of routine and toxic levels. Our study demonstrated that the REMEDi HS is particularly useful for a rapid estimate of drug concentrations in the samples from emergency cases when calibrators are not readily available. Our study also showed that this system can be used for the therapeutic monitoring of ranitidine, bromisovalum, lidocaine, and diphenhydrmine.

Occupational lead exposure and blood pressure

BACKGROUND

To assess the relation between occupational lead exposure and elevated blood pressure with consideration of a possible confounding effect by noise exposure.

MATERIALS AND METHOD

Some 112 male and 110 female workers at two lead battery manufacturing factories were recruited for this 1992 study in Taiwan. Study participants received regular physical examinations, including standard measurement of blood pressure, body height/weight. Current occupational exposures to lead and noise were measured by a personal sampling scheme and instruments, and included individual ambient lead/noise exposure and blood lead level.

RESULTS

Among the 222 battery-factory workers, the average blood lead level was 56.9 +/- 25.5 micrograms/dl (mean +/- standard deviation), the average concentration of ambient lead exposure was 0.190 +/- 0.331 mg/m3, average noise exposure was 85.9 +/- 5.7 dBA, average systolic blood pressure was 125.2 +/- 14.9 mmHg, average diastolic pressure was 80.2 +/- 10.9 mmHg, and average mean arterial pressure was 95.2 +/- 11.1 mmHg. After considering all possible confounding variables, multivariate regression analyses demonstrated that current blood lead level was not a significant predictor for both systolic and diastolic blood pressures in either sex. In the final model, body mass index and years of working in the factory were the only two factors significantly associated with a change in blood pressure. No evidence of an effect of ambient lead exposure or noise exposure on blood pressure were found.

CONCLUSIONS

The present study suggests that short-term lead exposure, either ambient lead exposure or blood lead level, was not related to blood pressure change among workers who had been exposed at work to occupational lead. These results add to the body of evidence indicating that blood lead exposure does not adversely affect blood pressure.

A comparative analysis of various EMG pattern recognition methods

Identification of motions of the neck and shoulders using the electromyographic (EMG) signal was investigated in this study. Three discrimination methods, the Euclidean distance measure (EDM), the weighted distance measure (WDM) and the modified maximum likelihood method (MMLM), were used to compare the conventional autoregressive (AR) and cepstral coefficients with closely positioned (C-type) and separately located (S-type) electrode arrangements. Surface electrodes were bilaterally located on and between the sternocleidomastoid and the upper trapezius muscles. The EMG signals obtained during 20 repetitions of 10 motions were analyzed for each subject. Results from nine subjects showed that the mean recognition rate of the cepstral coefficients was at least 5% better than that of the AR coefficients for the S-type signals, while the improvement was less obvious for the C-type signals. The MMLM obtained the best discrimination results of the three discrimination methods. The S-type signals achieved higher recognition rates than the C-type signals in most cases. Among the various combinations of feature sets, classifiers and electrode arrangements proposed in this study, the combination of the cepstral coefficients and the MMLM with the S-type arrangement achieved the best discrimination efficiency. The proper choice of five of 10 motions raised the recognition rate to more than 97%.

Exercise test in acute myocardial infarction

Although maximal oxygen consumption (VO2max) and oxygen consumption at anaerobic threshold (VO2AT) were used to measure cardiac function, the clinical significance in acute myocardial infarction (MI) has not been reported. The purpose of this study was to compare VO2max and VO2AT between post-MI patients and healthy men and to correlate the parameters to other clinical measures. Forty-three active healthy men, 44 sedentary healthy men, and 43 post-MI patients were studied using incremental cycle exercise test. Their work rates, oxygen consumption, heart rates, oxygen pulses, ventilation, and other parameters at VO2max and VO2AT were determined with spirometer, gas concentration analyzer, and electrocardiograph. Anaerobic threshold was determined by analyzing the ventilatory parameters. Most of the exercise test parameters at VO2max were greatest in the active men, intermediate in the sedentary men, and least in the post-MI patients (P < 0.01) whereas the rate-pressure products of the active men and sedentary men were not significantly different from each other and were greater than those of the post-MI patients (P < 0.01). In the post-MI patients, VO2max was inversely correlated to the peak serum level of creatine phosphokinase MB isoenzyme (P < 0.01) and associated with extensive infarction (P < 0.05). Most of the parameters at VO2AT were greater in the active men than in the sedentary men (P < 0.01) but not significantly different between the sedentary men and post-MI patients. In the post-MI patients, VO2AT was significantly correlated to left ventricular ejection fraction (P < 0.01) and associated with heart failure (P < 0.05). The results revealed that VO2max and VO2AT had different clinical significance in post-MI patients; VO2max was related to the infarct size, and VO2AT was related to the pumping function of heart.

Cardiorespiratory function, flexibility, and body composition among geriatric Tai Chi Chuan practitioners

OBJECTIVE

To evaluate the health-related fitness of geriatric Tai Chi Chuan (TCC) practitioners.

DESIGN

Case-control study of a TCC group and a group of sedentary controls.

SETTING

Research project at a hospital-based exercise physiology laboratory.

PARTICIPANTS

Seventy-six community-dwelling senior persons (mean age 69.3 +/- 3.9 yr), a TCC group that included 22 men and 19 women and a control group of sedentary subjects that included 18 men and 17 women with matched age and body size.

INTERVENTION

The TCC group had practiced TCC regularly for 11.8 +/- 5.6 years, with an exercise frequency of 4.3 +/- 1.3 times per week. Each session included 20 minutes of warm-up, 24 minutes of TCC training, and 10 minutes of cool-down. Exercise intensity was estimated to exceed 70% of maximal heart rate (HRmax).

MAIN OUTCOME MEASURE

Breath-by-breath measurement of cardiorespiratory function was obtained during the incremental exercise of leg cycling. Flexibility of thoracic/lumbar spine was measured by an electronic inclinometer. Percentages of body fat was calculated from biceps and subcapsular skinfolds.

RESULTS

In the peak exercise, men in the TCC group showed 19% higher peak oxygen uptake (VO2peak) in comparison with their sedentary counterparts (26.9 +/- 4.7 mL/kg/min vs 21.8 +/- 3.1 mL/kg/min). Women in the TCC group also showed 18% higher VO2peak than in the sedentary group (20.1 +/- 2.9 mL/kg/ min vs 16.5 +/- 2.0 mL/kg/min). The TCC group also showed higher oxygen uptake at the ventilatory threshold. In addition, the TCC practitioners were characterized by greater flexibility and lower percentage of body fat in comparison with their sedentary counterparts.

CONCLUSION

It is concluded that TCC training has benefits for health-related fitness, and it may be prescribed as a suitable conditioning exercise for the elderly.

The hypothalamus-pituitary-ovary and hypothalamus-pituitary-thyroid axes in spinal cord-injured women

Sixteen women with spinal cord injury (SCI) underwent studies of the hypothalamus-pituitary-ovary (HPO) and hypothalamus-pituitary-thyroid (HPT) axes with luteinizing hormone (LH) releasing hormone (LHRH) and thyrotropin (TSH) releasing hormone (TRH) stimulation tests during the early follicular phase. The mean interval from injury to participation in this study was 7.5 years (range, 1.5 to 13.1). All subjects were menstruating regularly. Five (35.7%) SCI subjects who were menstruating before injury had postinjury amenorrhea for 1 to 12 months, and the other nine (64.3%) SCI subjects had no interruption of menstruation after injury. Two SCI subjects whose injury occurred in preadolescence proceeded to menarche without any delay. The amount of menstrual flow was noted to be reduced in nine (64.3%) SCI subjects. Two and three SCI subjects had elevated follicle-stimulating hormone (FSH) and prolactin (PRL) levels, respectively. LH responses to LHRH were significantly higher in the SCI group (P < .001). Ten (62.6%) SCI subjects had enhanced LH responses to LHRH. The mean TSH, PRL, and FSH responses to TRH and LHRH of the SCI group were not significantly different from those of age-matched controls. However, five (31.2%), four (25.0%), and five (31.2%) SCI subjects had enhanced TSH, PRL, and FSH responses to TRH and LHRH, respectively. Six (37.5%) SCI subjects had a delayed FSH response to LHRH. In total, 13 (81.2%) SCI subjects had at least one axis abnormality. These findings are consistent with the hypothesis that changes of central neurotransmitters may occur after SCI.

Prospective study of noise exposure during pregnancy on birth weight

To examine the effect of noise exposure during pregnancy on infant birth weight, a well-characterized cohort of 200 pregnant women in the first trimester participating in prenatal care clinics was followed throughout gestation (in Taiwan, 1991). Individual 24-hour noise exposure of all women was prospectively measured, and information regarding possible noise exposure from traffic and occupation was also obtained. Noise exposure during pregnancy was correlated with the birth weights of the women's babies. No association between personal noise exposure measured in decibels (less than 85 dBALeq during pregnancy) and birth weight was found. Possible occupational noise exposure (indicated by working in a manual job), traffic noise exposure (indicated by distance between the home and main streets), and a history of listening to amplified music and using personal listening devices during pregnancy also showed no effect on infant birth weight. Maternal weight, maternal weight gained during pregnancy, gestational age, and infant's sex were the four factors that correlated significantly with birth weight. The noise exposure experienced by women during pregnancy may not be great enough to affect their infants' birth weight.

Lead poisoning caused by contaminated Cordyceps, a Chinese herbal medicine: two case reports

Two cases of lead poisoning, caused by the Chinese herbal medicine Cordyceps, were reported to the Department of Health in a laboratory-based blood lead surveillance program. Such unusual cases of lead poisoning have not been previously reported. These two patients took Cordyceps herbal medicine for treatment of underlying diseases. Loss of appetite and anemic signs of lead poisoning were manifested in one patient with a blood lead level of 130 microg/dl, while the other patient was asymptomatic with a blood lead level of 46 microg/dl. The lead content in the Cordyceps powder was found to be as high as 20 000 ppm. After cessation of intake in the asymptomatic patient, and cessation of intake and treatment with chelating agents in the symptomatic patient, the blood lead levels returned to normal range. This report raises concerns about lead poisoning from unusual herbal medicine worldwide.

Clinical experience in rehabilitation of spinal cord injury associated with schizophrenia

OBJECTIVE

To identify the clinical features and rehabilitation outcomes in spinal cord injury (SCI) patients with preexisting schizophrenia.

DESIGN

A retrospective study conducted by reviewing the charts of all patients diagnosed with both SCI and schizophrenia hospitalized from 1987 throughout 1994 in 2 rehabilitation units.

SETTING

Rehabilitation wards of two hospitals in Taiwan.

PATIENTS

Seventeen traumatic SCI patients with schizophrenia, including 7 men and 10 women. Patients without neurological deficits were excluded.

INTERVENTION

All subjects received psychiatric intervention and intensive rehabilitation programs during hospitalization.

MAIN OUTCOME MEASURES

The injury pattern and psychiatric condition were described. Abilities of locomotion, management of activities of daily living, and bladder control were measured.

RESULTS

Fifteen injuries caused by a voluntary fall subsequently resulted in thoracolumbar insult. Ten incomplete paraplegics were able to ambulate with or without a device on discharge. Four subjects had poor bladder control. The outcome of self-care skills was worse in those with high level injury. Psychiatric symptoms were one of the main obstacles during rehabilitation.

CONCLUSION

Voluntary fall that caused thoracolumbar injuries was the main cause of injuries in these patients. Psychiatric symptoms were present in the majority and might hinder the prognosis of treatment. Nevertheless rehabilitation programs were found to benefit subjects after their psychiatric problems were under control.

Blood lead levels in Taiwanese adults: distribution and influencing factors

Five-thousand nine-hundred thirteen Taiwanese adults were selected by multistage sampling methods to investigate environmental lead exposure in Taiwan. The blood specimens were distributed to six laboratories for blood lead levels (BLL) measurement. The mean BLL of the 5913 Taiwanese adults was 8.28 +/- 5.39 microg/dl, with a maximum level of 57.6 microg/dl. The median was 7.0 microg/dl and 90th percentile was 15.0 microg/dl. BLLs were associated with gender, ethnic group, education level, smoking, alcohol consumption, herbal drug consumption, milk consumption, sources of drinking water, level of urbanization, and occupational lead exposure. These results showed that BLLs in Taiwanese adults were stable during the 2-year study. Most of the influencing factors were consistent with other studies, while local risk factors, such as Chinese herbal drug consumption are important ways of preventing the general population from overexposure to lead.

Three-year survey of blood lead levels in 8828 Taiwanese adults

The purpose of this study was to investigate environmental lead exposure in the general Taiwanese population. A total of 8828 Taiwanese adults selected by a multistage sampling method were investigated. Characteristics of the participants were ascertained by questionnaire and 10 ml venous blood was drawn by public health nurses. The blood specimens were distributed to six laboratories for blood lead level (BLL) measurement. A quality control program was applied during the analysis of the BLLs in order to improve precision and accuracy. The arithmetic mean BLL of the 8828 Taiwanese adults was 7.70 +/- 5.23 micrograms/dl, with a maximal level of 69.1 micrograms/dl. The median was 6.5 micrograms/dl and the 90th percentile was 14.0 micrograms/dl. After logarithmic transformation, the geometric mean was 1.84 +/- 0.67 microgram/dl. This study also found that elevated BLLs were associated with certain personal characteristics, i.e., gender, ethnic group, and education level; life-style factors, such as smoking, alcohol consumption, Chinese herbal drug consumption, milk consumption, and sources of drinking water; residential location, i.e., level of urbanization; and occupational history of lead exposure. However, age, floor level of residence, distance from house to road, and betel nut consumption were not associated with elevated BLLs. These results showed that BLLs in the Taiwanese population were not higher than those in developed and developing countries. Most of the influencing factors were also found in other studies; however, local factors such as ethnic group, Chinese herbal drug consumption, and sources of drinking water are important considerations in Taiwan when examining ways to prevent overexposure to lead in the general population.

Two-year trends in cardiorespiratory function among older Tai Chi Chuan practitioners and sedentary subjects

OBJECTIVE

To evaluate the training effects of Chinese shadow boxing, Tai Chi Chuan (TCC), on the maintenance of cardiorespiratory function in older individuals.

DESIGN

Prospective study of a cohort of TCC practitioners and a group of sedentary controls examined 2 years after initial examination.

SETTING

Research project at a hospital-based exercise physiology laboratory.

PARTICIPANTS

Eighty-four community-dwelling older adults (mean age: 64 +/- 9 years) with no significant cardiovascular, pulmonary, and musculoskeletal disease completed this study. The TCC group, 23 male and 22 female subjects, had been practicing TCC regularly for 6.7 +/- 3.3 years. The control group included 21 male and 18 female sedentary subjects with age and body size matched to the TCC group.

INTERVENTION

During the period of the study, the TCC practitioners practiced TCC 5.0 +/- 1.1 times per week. Each session included 20 minutes of warm up, 24 minutes of TCC training, and 10 minutes of cool down. The baseline cardiorespiratory function was recorded in the initial exercise test. The same measurements were repeated 2 years later to determine the rate of decline of cardiorespiratory function. Furthermore, heart rates (HR) were monitored in 18 men and 16 women during the performance of TCC to determine the exercise intensity of TCC.

MAIN OUTCOME MEASURE

The study measured 2-year trends of cardiorespiratory function in both groups.

RESULTS

In the TCC group, the males showed a 2.8% decrease in maximal oxygen uptake (VO2max) from 31.6 +/- 7.6 mL x kg-1 x min-1 to 30.7 +/- 7.1 mL x kg-1 x min-1; the females showed a 2.9% decrease in VO2 max from 20.7 +/- 2.3 mL x kg-1 x min-1 to 20.1 +/- 2.5 mL x kg-1 x min-1. In contrast, the male control group showed a 6.6% decrease in VO2max from 24.4 +/- 4.4 mL x kg-1 x min-1 to 22.8 +/- 4.4 mL x kg-1 x min-1; the females showed a 7.4% decrease in VO2max from 16.2 +/- 2.3 mL x kg-1 x min-1 to 15.0 +/- 2.7 mL x kg-1 x min-1. At the ventilatory threshold (VeT), the sedentary group also showed a significant decrease in VO2. During the steady-state performance of TCC, subjects' mean HR was approximately the HR at the VeT (53-57% of HRmax reserve).

CONCLUSION

The data substantiate that practicing Tai Chi Chuan regularly may delay the decline of cardiorespiratory function in older individuals. In addition, TCC may be prescribed as a suitable aerobic exercise for older adults.

Aircraft noise, hearing ability, and annoyance

The relationship between aircraft noise, loss of hearing, and annoyance was explored in a study in two schools located near an international airport in Taiwan. Sixth-grade students (N = 242) were recruited from two schools and were classified into high- and low-noise-exposure groups, based on environmental noise measurements. Personal-equivalent 24-h noise exposure was measured to determine noise exposure at the individual level, and it was compared with hearing threshold level and with aircraft noise measured at the environmental level. Individual hearing threshold levels did not differ between environmental high- and low-noise-exposure groups, as evidenced by the lack of difference between the two groups for noise exposure measured at the individual level. However, the proportion of students who were annoyed by aircraft noise was higher in the environmental high-noise-exposure group, although personal 24-h noise exposure was not a factor for annoyance. The results indicated that environmental noise measurement was not an appropriate criterion for assessment of auditory damage (or noise-induced hearing loss) in Taiwan. As well, aircraft-noise exposure in Taiwan did not appear to affect the hearing threshold but nonetheless annoyed schoolchildren near the airport.

Breathing-coordinated exercise improves the quality of life in hemodialysis patients

Breathing-coordinated exercise is a traditional Chinese exercise. These exercise maneuvers consist of slow diaphragmatic breathing, end-inspiratory pause, and Kegel's exercise. A total of 30 patients were enrolled in this study, with 12 patients as controls, to evaluate its effect on hemodialysis patients. Exercise was performed for 25 to 30 min twice a day for at least 3 months. Results from the exercise group showed a subjective improvement in appetite and physical strength, and an increase in the frequency of bowel movements, in addition to enhanced sexual activity and a significant increase in Karnofsky scores. Six patients in the exercise group underwent bicycle ergometry and demonstrated a stable maximal oxygen consumption, whereas the control group revealed a decline in maximal oxygen consumption. Photoelectric plethysmography and laser-Doppler flowmetry demonstrated a pulsatile enhancement of the peripheral microcirculation. Abdominal sonography revealed an oscillatory change in the diameter of the inferior vena cava. It was concluded that these gentle exercise maneuvers may improve the quality of life in hemodialysis patients, especially weak dialysis patients. The mechanism may be partly related to an improvement in microcirculation.

The application of cepstral coefficients and maximum likelihood method in EMG pattern recognition

A new technique for classifying patterns of movement via electromyographic (EMG) signals is presented. Two methods (conventional autoregressive (AR) coefficients and cepstral coefficients) for extracting features from EMG signals and three classification algorithms (Euclidean Distance Measure (EDM), Weighted Distance Measure (WDM), and Maximum Likelihood Method (MLM)) for discriminating signals representative of broad classes of movements are described and compared. These three classifiers are derived from Bayes classifier with some assumptions, the relationship among them is discussed. The conventional MLM is modified to avoid heavy matrix inversion. Six able-bodied subjects with two pairs of surface electrodes located on bilateral sternocleidomastoid and upper trapezius muscles were studied in the experiment. The EMG signals of 20 repetitions of 10 motions were analyzed for each subject. Experimental results showed that mean recognition rate of the cepstral coefficients was at least 5% superior to that of the AR coefficients. The improvement achieved by the cepstral method was statistically significant for all the three classifiers. Reasons for the superiority of cepstral features were investigated from the feature space and frequency domain, respectively. The cepstral coefficients owned better cluster separability in feature space and they emphasized the more informative part in the frequency domain. The discrimination rate of the MLM was the highest among three classifiers. Incorporation of the cepstral features with the MLM could reduce the misclassification rate by 10.6% when compared with the combination of AR coefficients and EDM. Proper choice of five of ten motions could further raise the recognition rate to more than 95%.

Role of flexors in knee stability

The muscle strength of knee extensors is commonly used as an indicator of a patient's functional recovery following reconstruction of the anterior cruciate ligament (ACL). The knee flexors are dynamic stabilizers that prevent tibial anterior displacement and may reinforce the function of the ACL. The purpose of this study was to examine the relationship of knee flexor performance assessed by isokinetic dynamometer and clinical evaluations including KT-1000 stability tests, shuttle run tests, thigh and calf circumference and range of motion of the knee joint. Ten patients who received ACL reconstruction over a 3- to 5-year period were included in this study, as were 15 normal controls who were tested for comparison. There was no significant difference in the time taken for the shuttle run test between normal controls and patients who underwent ACL, but there was a positive correlation between the shuttle run test and laxity of the knee joint. The knee laxity of ACL patients was significantly greater than that of the normal controls under passive anterior force. However, no significant difference was seen in the stability test under active contraction of the knee extensors. In addition, a positive correlation was seen between the KT-1000 knee ligament arthrometry test results and both torque acceleration energy and the average power of the flexors. These results suggest that physical therapy for patients following ACL reconstruction should emphasize the explosiveness of knee flexors to help strengthen the dynamic stability of the knee joint and motor performance.

Pulmonary embolism presenting as syncope in paraplegia: a case report

Syncope as an initial presentation of pulmonary embolism is unusual. A 16-year-old girl, with T7 paraplegia after a traumatic spinal cord injury, developed syncope on the 33rd hospital day. The episode occurred approximately 3 hours after her first tilting table training and just after her attendant had assisted passive range-of-motion exercise. Subsequent studies showed pulmonary embolism at the left lower branch of the left pulmonary artery, and the branch to lower segment of the lingual lobe. Doctors should be alert to possible diagnosis of pulmonary embolism in such high-risk patients, especially when new onset symptoms or signs appear.

The roles of reactive oxygen species and endogenous opioid peptides in ischemia-induced arrhythmia of isolated rat hearts

Although the formation of oxygen-derived free radicals (or reactive oxygen species; ROS) and the release of endogenous opioid peptides (EOP) have been independently reported to be the major arrhythmogenic factors in ischemic hearts, possible relations between these two factors have seldom been investigated. Thus, we studied whether the ROS and EOP were related in the progression of ischemia-induced arrhythmias. Isolated rat hearts perfused in the Langendorff mode were treated with dynorphin A1-13 (kappa EOP receptor agonist), and/or allopurinol (xanthine oxidase inhibitor), before the onset of ischemia induced by ligating the left coronary arteries. Ischemic period lasted for 30 min, during which cardiac rhythms were recorded. At the end of ischemia, hearts were analyzed for the glutathione and ascorbate levels. Allopurinol (100 nmoles/heart) was effective in reducing the severity of arrhythmia (arrhythmia score: Mean +/- SEM 3.00 +/- 0.80 for allopurinol, 5.75 +/- 0.41 for placebo, p < 0.01), while dynorphin (10 micrograms/heart) potentiated the arrhythmia (6.71 +/- 0.52, p < 0.05 vs. placebo). Coadministration of allopurinol and dynorphin was capable of reducing arrhythmia (5.57 +/- 0.65) when compared with the administration of dynorphin alone (6.71 +/- 0.52, p < 0.05). Tissue oxidative stress was evaluated by the concentrations of glutathione (GSH) and ascorbate. Allopurinol did not significantly elevate tissue GSH concentrations (1.46 +/- 0.05 mumoles/g wet wt) in ischemic hearts, while dynorphin alone significantly decreased the GSH concentrations (0.96 +/- 0.08, p < 0.05) when compared with the placebo (1.32 +/- 0.03). The dynorphin-induced GSH decrease cannot be reversed by coadministration with allopurinol (0.90 +/- 0.104). Allopurinol significantly elevated tissue ascorbate levels (0.16 +/- 0.01) when compared with placebo (0.10 +/- 0.01, p < 0.05). Interestingly, dynorphin alone also elevated the tissue ascorbate concentrations (0.16 +/- 0.02). Coadministration of allopurinol and dynorphin further spiked the ascorbate levels (0.28 +/- 0.05, p < 0.01). In conclusion, the results suggested that ischemia-induced arrhythmia mechanisms might involve the formation of superoxide and other ROS, which were probably generated from the release of EOP (or EOP/EOP receptor interactions). Superoxide, the formation of which can be inhibited by allopurinol that exerted antiarrhythmic effect, was probably scavenged by ascorbate in myocardial ischemia. The ROS resulting from EOP/EOP receptor interactions were probably scavenged by glutathione system. Elevated ascorbate levels in dynorphin-treated hearts might result from the compensatory synthesis induced by decreased glutathione levels.

Assessment of interlaboratory performance on the measurement of blood lead levels in Taiwanese adults

The purpose of this proficiency study was to assess the accuracy and consistency of blood lead level (BLLs) measurements in a study of Taiwanese adults. Three methods, including a certified blood accuracy test, an interlaboratory precision test and an intertime repeated measurement test, were applied to the six participating laboratories. Accuracy tests showed that most of the blood lead measurements were within the acceptable criteria proposed by United States Center for Disease Control and Prevention (U.S. CDC). However, an average of 11% underestimation was found at BLLs below 15 micrograms/dl. Coefficients of variation (CVs) were high in the first 3 months. After technical improvements, the CVs were reduced to acceptable limits of around 15% at low target lead values and 7% at high lead values. Interlaboratory variations of measurements in blood from ten normal healthy donors showed that the standard deviations were less than 2 micrograms/dl, which is within the acceptable criteria of +/- 4 micrograms/dl, in 8 out of 10 samples. Repeated measurements of BLLs in 54 blood samples over two months showed that most of the differences were within the acceptable range with a few exceptions. The mean BLLs measured in the baseline (pre-test) and two months later (post-test) were nearly identical. This proficiency test provides comparable and reliable results of BLL estimations in this multilaboratory study. However, the accuracy and consistency at low BLLs need to be improved.

Establishment of an occupational diseases surveillance system to monitor blood lead levels in Taiwan

BACKGROUND

Occupational diseases share many common characteristics with infectious diseases. However, the successful approach of using surveillance systems to eradicate infectious diseases has never been applied to the control and prevention of occupational diseases.

METHODS

On the basis of a nationwide survey of blood lead levels in the general population in Taiwan, we (the Ministry of Health, Taiwan) have developed an obligatory surveillance system for blood lead.

RESULTS

This government-administered system, which uses laboratory data as its source of information, enrolls all workers whose blood lead level exceeds regulation points (40 microgram/dl for men and 30 micrograms/dl for women). A Group of Health Promotion of Lead-using Workers (GHPLW) has been organized to be responsible for conducting epidemiological investigations to locate exposure sources in the workplace and to improve the working environment of cases and other workers with the same exposure.

CONCLUSIONS

We emphasize that the accomplishment of the GHPLW's task depends not only on "curing" the case, but also on eradicating the lead exposure source and decreasing the blood lead level of workers in the workplace during long-term follow-up. The system aims to upgrade occupational disease control to the stage of specific prevention and health promotion. The establishment of this system is a historic step in industrial hygiene and occupational disease prevention in Taiwan.

Determination of extracellular glutathione in rat brain by microdialysis and high-performance liquid chromatography with fluorescence detection

A method for the continuous monitoring of extracellular glutathione (GSH) concentrations in rat brain has been developed. This method involved the in vivo sampling of brain extracellular fluid by microdialysis perfusion and the subsequent analysis by high-performance liquid chromatography (HPLC) with fluorescence detection. Perfusates from the microdialysis probes were directly derivatized with methanolic monobromobimane which acted as the fluorescence tag. Separation of the derivatized perfusate was achieved on narrow-bore reversed-phase C18 columns. Recoveries of GSH from the microdialysis probes ranged from 1.5% to 4%. The basal extracellular GSH concentration in rat (Sprague-Dawley) brain cortex was found to be 2.10 +/- 1.78 microM (mean +/- S.D.) (results of 18 rats). Fluorescence detection and separation on narrow-bore columns provided adequate sensitivity for accurate determination of brain extracellular GSH concentrations in rats. With this method, the extracellular GSH concentrations in the cerebral cortex were found to be significantly elevated upon the onset of cerebral ischemia induced by the ligation of bilateral common carotid arteries.

The use of surface EMG in knee extensor moment prediction

A systematic method of EMG quantification is developed to estimate the isometric muscle moment directly from quantified surface EMG. This method includes the EMG Signals acquired from an acupuncture point Fu-Tu located on the quadriceps muscle group, an EMG smoothing scheme, an electromechanical time lag estimation, and a mathematical model with the polynomial regression function to quantify the EMG. Three subjects were asked to be tested on the CYBEX II dynamometer with a knee joint angle of 90 degree flexion and hip joint angle of also 90 degrees. They were asked to perform "two" trials of maximal voluntary contraction and "three" trials of free voluntary contraction of the isometric exercise. The first two trials were used to build up the quantification model, and the latter three trials served as data for the validation of the method. A Medelec MS92 EMG system with surface EMG electrodes was used to acquire the EMG Signals. In the determination of the regression order of the polynomial equations, the threshold value 0.0001 of the difference of the coefficient of determination values was used. The results of the polynomial regression orders are all 6 for three subjects, which reflects a tendency of nonlinear behavior of the EMG/moment relationship. A validation scheme was proposed to calculate the root mean square difference (RMSD) of the measured knee extensor moments from the CYBEX II dynamometer and estimated moments from the EMG quantification. The mean values of the RMSD of the three subjects were 0.0597, 0.0679 and 0.1080. These results demonstrate that the present approach can estimate the isometric muscle moment exerted by the quadriceps muscle group.

Blood lead levels in the general population of Taiwan, Republic of China

The purpose of this study was to investigate the environmental lead exposure of the general population in Taiwan. A total of 2919 residents of Taiwan were selected by multistage sampling methods. The participants were characterized by questionnaires and 10 ml venous blood was collected for blood lead measurement. A quality assurance/quality control program was designed during the analysis of blood lead levels. The mean blood lead level of 2719 residents without occupational lead exposure was 8.29 +/- 5.92 micrograms/dl. After adjustment for age and sex distribution to the Taiwan general population, the mean blood lead level was 8.10 micrograms/dl. Adjusted for an 11% underestimation of blood lead levels among the six laboratories, the mean blood lead level was estimated to be 8.99 micrograms/dl. This study also found that blood lead levels were associated with personal characteristics, i.e., gender, ethnic group, education level; lifestyle factors, i.e., smoking, alcohol consumption, sources of drinking water; and residential location, i.e., levels of urbanization, distance of house from the road. However, age, floor of residence, milk consumption, betel nut consumption, and Chinese herbal drug consumption were not found to be associated with blood lead levels. These results show that blood lead levels in Taiwan residents were not higher than in most developed and developing countries. Environmental lead pollution does not seem to be a serious problem in Taiwan.

DNA adducts and carcinogenicity of nitro-polycyclic aromatic hydrocarbons

We have been interested in the structure-activity relationships of nitro-polycyclic aromatic hydrocarbons (nitro-PAHs), and have focused on the correlation of structural and electronic features with biological activities, including mutagenicity and tumorigenicity. In our studies, we have emphasized 1-, 2-, 3-, and 6-nitrobenzo[a]pyrenes (nitro-B[a]Ps) and related compounds, all of which are derived from the potent carcinogen benzo[a]pyrene. While 1-, 2-, and 3-nitro-B[a]P are potent mutagens in Salmonella, 6-nitro-B[a]P is a weak mutagen. In vitro metabolism of 1- and 3-nitro-B[a]P has been found to generate multiple pathways for mutagenic activation. The formation of the corresponding trans-7,8-dihydrodiols and 7,8,9,10-tetrahydrotetrols suggests that 1- and 3-nitro-B[a]P trans-7,8-diol-9,10-epoxides are ultimate metabolites of the parent nitro-B[a]Ps. We have isolated a DNA adduct from the reaction between 3-nitro-B[a]P trans-7,8-diol-anti9,10-epoxide and calf thymus DNA, and identified it as 10-(deoxyguanosin-N2-yl)-7,8,9-trihydroxy-7,8,9,10-tetrahydro-3-ni tro-B[a]P . The same adduct was identified from in vitro metabolism of [3H]3-nitro-B[a]P by rat liver microsomes in the presence of calf thymus DNA. A DNA adduct of 3-nitro-B[a]P formed from reaction of N-hydroxy-3-amino-B[a]P, prepared in situ with calf thymus DNA was also isolated. This adduct was identified as 6-(deoxyguanosin-N2-yl)-3-amino-B[a]P. The same adduct was obtained from incubating DNA with 3-nitro-B[a]P in the presence of the mammalian nitroeductase, xanthine oxidase, and hypoxanthine.(ABSTRACT TRUNCATED AT 250 WORDS)

[Clinical application of the ice water test in evaluation of neurogenic bladder dysfunction]

Ice water test (IWT) and cystometrography (CMG) were performed on 51 in patients with spinal cord injuries (SCI) to evaluate the sensitivity and specificity of the IWT in detecting detrusor reflex. A three-step grading system as established by Balmaseda et al was applied to determine the presence of detrusor activity on IWT. The test was considered 3+ when the catheter was expelled from the bladder within one minute following instillation of 90 mL of ice water; a 2+ test indicated voiding around the catheter after instillation of 90 mL of ice water; and a 1+ IWT was defined as voiding around the catheter or expelling the catheter after instilling another 210 mL of ice water into the bladder. The results showed that the sensitivity of IWT in detecting the presence of detrusor reflex in patients with neurogenic bladder dysfunction was 96% and the specificity was 79%. Among the four patients having false positive IWT, three of them were diagnosed with poor-compliance bladders. One patient with false negative IWT was found to have severe detrusor-sphincter dyssynergy. There was a significant difference in the strength of detrusor activity among the patients with 3+ IWT, with 2+ IWT, and with 1+ IWT. IWT is a useful technique to predict the existence of detrusor reflex in SCI patients. Its use as a supplement method to cystometrogram could be helpful in the bedside evaluation of patients with neurogenic bladder dysfunction.

Cardiorespiratory responses of Tai Chi Chuan practitioners and sedentary subjects during cycle ergometry

Tai Chi Chuan (TCC; shadow boxing) is a traditional Chinese conditioning exercise. To evaluate its beneficial effect on cardiorespiratory function, 21 male and 20 female TCC practitioners, ranging in age from 50 to 64 years, voluntarily participated in this study. The control group comprised 23 male and 26 female sedentary subjects. Breath-by-breath measurement of the cardiorespiratory function was obtained during the incremental exercise of leg cycling. At the maximal exercise level, the oxygen uptake (VO2), O2 pulse and work rate of the TCC group were significantly higher than the respective values of the control group (p < 0.01). At the ventilatory threshold, the TCC group also showed a higher VO2, O2 pulse and work rate (p < 0.05). The results imply that TCC training may be beneficial to the cardiorespiratory function of older individuals. To estimate the exercise intensity of TCC, heart rate (HR) was monitored in 15 men and 15 women while they performed the classical Yang TCC. During the steady-state performance of TCC, the mean HR was 130 +/- 14 bpm for men and 127 +/- 13 bpm for women. The mean HR during TCC exceeded 70% of their HRmax. Our data substantiate that TCC is aerobic exercise of moderate intensity, and it may be prescribed as a suitable conditioning exercise for the elderly.

Synthesis of 3-nitrobenzo[a]pyrene bay-region trans-7,8-diol anti-9,10-epoxide and the corresponding N2-deoxyguanosine adduct

3-Nitrobenzo[a]pyrene (3-nitro-BaP) is a potent mutagenic environmental contaminant, and its biological activities have been intensively studied. It is significant to prepare its reactive metabolites and the corresponding modified DNA adducts for biological studies. The synthesis of its oxidized proximate metabolite trans-7,8-dihydro-3-nitrobenzo[a]pyrene (3-nitro-BaP-trans-7,8-dihydrodiol, 1), its oxidized ultimate metabolite trans-7,8-dihydroxy-anti-9,10-epoxy-7,8,9,10-tetrahydro-3- nitrobenzo[a]pyrene (3-nitro-BaP-DE, 2), and the corresponding DNA adduct 10-(deoxyguanosin-N2-yl)-7,8,9-trihydroxy-7,8,9,10-tetrahydro-3- nitrobenzo[a]pyrene is described.

Rapid and reliable high-performance liquid chromatographic method for analysing human plasma serotonin, 5-hydroxyindoleacetic acid, homovanillic acid and 3,4-dihydroxyphenylacetic acid

The simultaneous measurement of homovanillic acid, 3,4-dihydroxyphenylacetic acid, serotonin and 5-hydroxyindoleacetic acid in human plasma by an ultrafiltration and microbore high-performance liquid chromatography-electrochemical detection technique is established. Conventional preparation of blood is very tedious and time-consuming, but isocratic separation of the analytes in plasma ultrafiltrates using a microbore column could be achieved within 10 min. Hence, theoretically, over 140 analyses can be performed in a working day. The detection limit (signal-to-noise ratio = 3) of this method is about 0.1-0.5 pg per injection for all analytes. The required volume of plasma samples can be less than 100 microliters. Hence, blood loss is minimal, especially in repeated blood sampling. This rapid, simple and sensitive method can, therefore, be used as a routine clinical tool in the simultaneous measurement of plasma homovanillic acid, 3,4-dihydroxyphenylacetic acid, serotonin and 5-hydroxyindoleacetic acid.

Simultaneous measurement of serotonin, catecholamines and their metabolites in mouse brain homogenates by high-performance liquid chromatography with a microbore column and dual electrochemical detection

A dual electrochemical detector with two working electrodes (anode and cathode) suitable for high-performance liquid chromatography with a microbore octadecylsilica column was applied for the simultaneous measurement of norepinephrine, epinephrine, dopamine, 3,4-dihydroxyphenylacetic acid, homovanillic acid, 5-hydroxyindoleacetic acid, 3-methoxytyramine and 5-hydroxytryptamine (serotonin) in mouse brain homogenates. Microbore high-performance liquid chromatography provides very good resolution of these analytes and offers selective detection of biogenic amines and their metabolites on the basis of their retention behaviour and electrochemical reversibility. The large early-eluting peak of brain homogenates was eliminated on cathodic detection, thereby providing reliable measurements of early eluates. The detection limit of this method was ca. 0.2-0.5 pg per injection for all components, at a signal-to-noise ratio of 3. Owing to the high sensitivity, the brain tissue samples could be kept very small (less than 10 mg). Isocratic separation of these analytes was achieved within 15 min; hence over 90 analyses could be performed in a single working day. This simple, efficient and sensitive method can be used as a basic research tool for the assaying of biogenic amines and their metabolites in brain homogenates.

Traumatic spinal cord injuries in the rural region of Taiwan: an epidemiological study in Hualien county, 1986-1990

In order to survey the epidemiological characteristics of traumatic spinal cord injuries (SCI) in Hualien county, a retrospective study was conducted from January 1986 to December 1990 in four local general hospitals. During this period, 135 traumatic SCI patients were identified and 99 of them were residents of Hualien county. The estimated annual incidence of traumatic SCI in Hualien county was 56.1 per million population. As a result of injury 36 patients were tetraparetic, 33 tetraplegic, 12 paraparetic and 18 paraplegic. The male/female ratio was 4:1. The mean age of onset for male patients was 44 years, and that for female patients was 46 years. The major causes of SCI were traffic accident (61.6%) followed by accidental falls (23.3%). The average duration of hospitalisation ranged from 62 days in paraparetics to 132 days in tetraplegics. Ten patients died of respiratory failure or sepsis, and the mortality rate was 10.1%. Our data revealed that traumatic SCI was prevalent in Hualien county in comparison with epidemiological studies elsewhere. The special population composition of Hualien county and the preponderance of the motorcycle as a transportation vehicle in this area might result in its unique epidemiological characteristics.

Anaerobic threshold and maximal oxygen consumption during arm cranking exercise in paraplegia

The major purpose of this investigation was to compare the anaerobic threshold (AT) and maximal cardiopulmonary responses to arm exercise between persons with paraplegia and the able-bodied. The locomotive stress on the heart in paraplegic subjects was also examined. Thirty-nine paraplegic subjects (T1-L4 lesions) and 32 able-bodied subjects completed a continuous, progressive, resisted arm cranking exercise test. The AT was determined from the ventilatory parameters. At the AT, the mean values of Vo2/body weight (BW) for class II (T1-T5, N = 9), III (T6-T10, N = 11), and IV (T11-L4, n = 19) paraplegic subjects were 10.9, 13.2, and 13.5mL/kg/min, respectively, and only class II had significantly lower value than the able-bodied (14.4mL/kg/min). During maximal exercise, the mean values of maximal oxygen consumption per body weight (Vo2max/BW) for class II and III paraplegics were 17.4 and 17.7mL/kg/min, respectively, which were significantly lower (p < 0.05) than that of class IV (21.3mL/kg/min) and the able-bodied (28.2mL/kg/min). The heart rate (HR) during wheelchair-propelling (119bpm, n = 37) was significantly less than that at the AT (134bpm), but the HR during crutch-walking (151bpm, n = 17) was significantly higher. The results indicate that both submaximal and maximal cardiopulmonary functions in high-lesion paraplegics were less than that of the able bodied. Furthermore, the intensity of wheelchair-propelling at comfortable speed is not enough for improving the cardiopulmonary functions.

A single amino acid exchange transfers VP16-induced positive control from the Oct-1 to the Oct-2 homeo domain

The selective association of the herpesvirus trans-activator VP16 with the human Oct-1 homeo domain is a model for differential positive transcriptional control by homeo domains. VP16 discriminates between the closely related homeo domains of Oct-1 and Oct-2 by distinguishing among their seven amino-acid differences; these differences lie on the surface that is thought to be accessible when the homeo domain is bound to DNA. Only two of these seven differences are recognized by VP16, one in each of the first two alpha-helices of the tri-alpha-helical homeo domain. The major determinant for selective association with VP16 in vitro and VP16-induced positive control in vivo is a single glutamic acid residue at position 22 in the first alpha-helix of the Oct-1 homeo domain, but the acidic properties of this residue are not critical for association with VP16 in vitro or in vivo, because it can be replaced by glutamine with little or no deleterious effect. Mere replacement of the single corresponding alanine residue in the Oct-2 homeo domain with the key glutamic acid residue is sufficient to confer on the Oct-2 homeo domain the ability to associate with VP16 in vitro and respond to VP16-induced positive control in vivo. Thus, the specificity of homeo domain positive control can be conferred by a single amino acid difference.

Ethidium bromide provides a simple tool for identifying genuine DNA-independent protein associations

DNA-dependent and DNA-independent associations of DNA-binding proteins are important in transcriptional regulation. The analysis of DNA-independent associations frequently relies on assaying protein interaction in the absence of target DNA sequences. We have found that contaminating DNA in protein preparations can stabilize DNA-dependent associations that may appear DNA-independent. Three cellular proteins of 70, 85, and 110 kDa coimmunoprecipitated with the octamer motif-binding protein Oct-2 because of the presence of contaminating DNA in the cell extracts. In addition, heterodimer formation between Oct-1 (or Oct-2) and Pit-1 during protein-affinity chromatography was stabilized by the contaminating DNA. In both instances, these DNA-dependent protein associations were selectively inhibited by ethidium bromide in the precipitation reaction without any evident effect on DNA-independent protein associations. Thus, ethidium bromide may serve as a simple and general indicator of DNA-dependent and DNA-independent protein associations.

Promoter-selective activation domains in Oct-1 and Oct-2 direct differential activation of an snRNA and mRNA promoter

The promoter specificity of transcriptional activators is generally thought to be conferred by the specificity of the DNA-binding domain, which brings the activation domain to the appropriate promoter sequence. We show here, however, that Oct-1 and Oct-2 can differentially activate transcription not through DNA binding specificity but instead through the use of promoter-selective activation domains. These distinct activation domains lead to stimulation of the U2 small nuclear RNA promoter by Oct-1 and an mRNA promoter by Oct-2. An Oct-2 variant, called Oct-2B, differs from Oct-2 by an Oct-1-related C-terminal extension that results from alternative splicing. This variant gains the ability to activate the U2 small nuclear RNA promoter. Thus, the promoter selectivity of a transcriptional activator can be changed, in this case by alternative splicing, without affecting its DNA binding specificity.

Total cavopulmonary connection for surgical treatment of complex congenital heart disease

Diversion of vena caval flow directly into the pulmonary circulation--total cavopulmonary connection--has been tried at our hospital for two years as an alternative to the modified Fontan procedure for surgical treatment of complex congenital heart disease other than tricuspid atresia in 26 cases with six operative mortalities. The causes of death were low cardiac output in four, uncontrollable paroxysmal supraventricular tachycardia in one and airway obstruction in one. Except for one late death which occurred three months after surgery due to sepsis, the 19 patients who survived the operation were followed up for four to 27 months (mean 15 months). All of them improved clinically (NYHA Class 1). Graded bicycle exercise tests were performed in five of them at three to 12 months after surgery, and their exercise tolerance was comparable to that of patients with an atriopulmonary connection. In conclusion, total cavopulmonary connection is an acceptable alternative to the modified Fontan operation for surgical treatment of complex congenital heart disease, although longer follow-up is necessary.

The effects of physiotherapy on osteoarthritic knees of females

The purpose of this study was to investigate the effect of ultrasound and shortwave diathermy, with and without therapeutic exercise on osteoarthritic (OA) knees. From February 1987 to January 1989, we collected 94 OA knees from 61 female patients and divided them into 4 groups. Group 1 received ultrasound therapy, group 2 had shortwave diathermy, group 3 received ultrasound and an exercise program, and group 4 received shortwave diathermy and exercise therapy. All 61 patients (94 knees) were assessed by functional incapacity scoring and isokinetic testing before and after treatment. At the termination of treatment, all patients had significant improvement in both functional capacity and peak torque. This study failed to prove any significant difference in treatment effect between ultrasound and shortwave diathermy for chronic OA knees. However, the exercise program in addition to the diathermy did promote the treatment effect in both function and muscle torque.

Surgical treatment of tricuspid atresia

From April 1984 to July 1989, 6 consecutive patients underwent an orthoterminal repair for classical tricuspid atresia (TA). Their ages ranged from 6 to 14 years with a mean of 8.3 years. Four patients had ventriculoarterial concordance (VA-con) and 2 had ventriculoarterial discordance (VA-dis). One patient with VA-dis underwent a total cavopulmonary connection. The other five patients had modified Fontan operation. All 6 patients survived the operation. At a mean follow-up of 28 months, all patients were in the New York Heart Association Functional Class I. A follow-up color Doppler echocardiogram showed that the forward pulmonary flow was mainly during the ventricular diastolic phase except in one case. In this case, a tripartite right ventricle (RV) could be identified by angiocardiogram 4.5 years after the atrioventricular (A-V) connection without obliteration of the trabecular portion. A big "V" wave was demonstrated in the RV and pulmonary trunk. The pulmonary valve was closed in the ventricular diastolic phase. In the other case with an A-V connection and obliteration of the trabecular portion, revealed a fixed-open pulmonary valve with a forward flow more in the atrial systolic phase than in the ventricular systolic phase. The graded exercise test in these 2 patients with an A-V connection revealed a normal functional capacity. The mean maximal oxygen uptake was 8.4 +/- 0.1 METS. In the other 3 children without an A-V connection the mean maximal oxygen uptake was 6.6 +/- 0.5 METS. We concluded that the Fontan-like repair was the procedure of choice for TA, and that excellent surgical results could be obtained.(ABSTRACT TRUNCATED AT 250 WORDS)

Isokinetic study of muscle strength in osteoarthritic knees of females

The present investigation was aimed at assessing the difference in peak torque between normal and osteoarthritic (OA) knees in females. Fifty-five female osteoarthritic patients with 85 osteoarthritic knees were studied. Thirty-three normal females of similar age were also collected as a control group. The muscle torque of the knee flexor and extensor was assessed by a Cybex II dynamometer. The speed of isokinetic contraction was set at 30 RPM, 5 RPM, and 0 RPM. The muscle torque of the affected knee in patients with unilateral osteoarthritis was found to be significantly greater than that of those with bilateral osteoarthritis (p less than 0.05). The peak torque of OA patients at the faster speed (30 RPM) showed significant deterioration with age. Compared with the value for controls, the deficit of peak torque in geriatric patients was significant (p less than 0.05), especially at the faster speed (30 RPM). The decrease in extensor torque in OA knees tended to be greater than that of flexor torque, especially in patients less than 51 years of age at 5 RPM and 0 RPM. Age, duration of illness and the grading of X-ray change accounted for isokinetic torque differences in osteoarthritic knees.

Prevalence of cataract among the institutionalized elderly in Hong Kong

The Hong Kong 1981 Census found a high prevalence of blindness in the age group aged 65 and above. Visual defects short of blindness are also a special problem among the elderly and cataract is one of the most important causes. We have studied the prevalence of cataract among 546 subjects living in homes or hostels for the aged in a New Town in Hong Kong. Cataract was defined as having a lens opacity and visual acuity worse than 20/100 in either eye. A prevalence of 45% among men and 32% among women was found. There was significant difference in prevalence between men and women aged below 75 but little sex difference was noted for the older age groups. Among the cataract cases detected on screening, about half had not had the diagnosis made previously. The results confirm the need for more epidemiological and health care studies on the visual problems among the aged.

Evaluation of cardiovascular autonomic function tests in normal subjects

We studied autonomic function in 76 normal adults (aged 20-80 years, 46 men and 30 women) with noninvasive cardiovascular reflex tests. The autonomic function tests included heart rate (HR) response to standing up, during the Valsalva maneuver, deep breathing, diving, and blood pressure (BP) response to standing up, during immersion of the hand in ice water, and a sustained handgrip. The patients were connected to an EKG monitor. All tests were performed in the resting state. The results show that (1) HR response to standing up, during the Valsalva maneuver, and while deep breathing were less variable and more suitable for follow-up; (2) women had a greater fall in systolic BP after standing up, and less rise in diastolic pressure during sustained handgrip than did men; (3) age correlated negatively with the HR response to standing, to deep breathing, Valsalva ratio, and the cold pressure test. But, age correlated positively with a fall in systolic BP as women stood up, but not in men; (4) there is a significant correlation between the HR response to standing up and the HR response to deep breathing. We concluded that sex and age do have an influence on some autonomic test results. The influence of the former is more related to sympathetic function while that of the latter is related to both the sympathetic and parasympathetic system. In addition, a normal range of autonomic function test results in healthy subjects is proposed.