The effects of cleanroom noise intensity and frequency on physiological measures and subjective responses.

BACKGROUND: Workplace noise exposure gains growing attention in high tech industry. OBJECTIVE: This study investigated the noise effect on physiological and subjective responses in semiconductor manufacturing clean room environment. METHODS: Twenty subjects including 10 males and 10 females completed all phases of the experiment. Each subject was asked to participate in four treatment combinations of two noise intensities [65 dB(A) and 80 dB(A)] × two frequency levels [high and low]. For each treatment condition, the subject was exposed to the specified noise condition in a sound proof cabin for one hour. The physiological measures included blood pressure and heart rate. The subjective measures included noise sensitivity, fatigue and annoyance. RESULTS: The ANOVA results indicate that long-time noise exposure caused significant increase in blood pressure (p< 0.001). Furthermore, the noise intensity by time interaction effect was found to be significant on annoyance and fatigue. CONCLUSIONS: The findings suggest that prolonged exposure to noise intensity at 80 dB(A) would result in a significant increase in physiological cost and subjective discomfort feeling. Thus, some countermeasures should be taken to reduce noise exposure and to promote health, and quality of working life.

Curcumin treatment protects against renal ischemia and reperfusion injury-induced cardiac dysfunction and myocardial injury.

OBJECTIVES: Renal ischemia and reperfusion (I/R) injury frequently leads to acute renal failure (ARF) and multiple-organ injury with a substantial morbidity rate. The primary cause of ARF-associated death is, however, cardiac failure instead of renal failure itself, and the pathogenesis of renal I/R-induced cardiac injury is still poorly understood. We evaluated the efficacy of curcumin pretreatment on cardioprotection. METHODS: Thirty Sprague-Dawley rats were evenly divided into 3 groups of sham-operated control, renal I/R injury, and a curcumin pretreatment group. Renal ischemia was conducted by bilateral occlusions of pedicles for 45 minutes, followed by 3 hours of reperfusion. The cardiac function was assessed by the left ventricular end-systolic-pressure-volume-relation (ESPVR), systolic pressure (SP), ejection fraction (EF), and stroke volume (SV). Myocardial injury was assessed based on creatine kinase muscle brain fraction (CK-MB) and Troponin I (cTnI), and kidney injury was assessed based on blood urea nitrogen (BUN) and creatinine. We also assessed the levels of tumor necrosis factor-α (TNF-α) and malondialdehyde (MDA) in the heart tissues. RESULTS: SV, EF, and SP reduced moderately during the ischemic phase with no major change in ESPVR. During reperfusion, SV, SP, and ESPVR initially increased, and then steadily decreased. Myocardial and kidney injury were marked by the increases in serum CK-MB and cTnI, and creatinine and BUN level. Curcumin pretreatment ameliorated ESPVR and attenuated injuries of both the heart and kidney resulting from I/R insult. CONCLUSIONS: Curcumin pretreatment improved cardiac contractility and attenuated myocardial and renal injury through reducing inflammatory response in the kidney and heart and oxidative stress in the myocardium.

Forensic Science in Support of Wildlife Conservation Efforts - Developments in Morphological and Chemical Approaches in Taiwan.

Parts from animals that are now endangered species (such as bear bile, rhino horn, and tiger bone) have long been important ingredients of traditional Chinese medicine (TCM). Deeply believing in the potency of these ingredients and coupled with substantial gains in wealth of the population in Taiwan in the 1980s, ugly scenarios came to light. Taiwan quickly became the target of investigation pursued by international wildlife conservationists. To provide scientific bases for the government's investigation efforts, morphological, chemical/physical, and genetic methods were developed to characterize TCM products. This review focuses on Taiwanese scientists' efforts on the following topic matters: (a) morphological approach to identify CITES-listed species from the turtle shells traded in the TCM market; (b) chromatographic and spectrophotometric methods for the identification and differentiation of bile products of different animal origins; and (c) gas chromatography-mass spectrometry method for the analysis of deer musk components and alleged musk products.

The prognosis for patients with osteosarcoma who have received prior manipulative therapy.

We evaluated the long-term outcome of patients with an osteosarcoma who had undergone prior manipulative therapy, a popular treatment in Asia, and investigated its effects on several prognostic factors. Of the 134 patients in this study, 70 (52%) patients had manipulative therapy and 64 (48%) did not. The age, location, and size of tumour were not significantly different between the groups. The five-year overall survival rate was 58% and 92% in the groups with and without manipulative therapy (p = 0.004). Both the primary and overall rates of lung metastasis were significantly higher in the manipulative group (primary: 32% vs 3%, p = 0.003; overall lung metastasis rate: 51.4% vs 18.8%, p < 0.001). Patients who had manipulative therapy had higher local recurrence rates in comparison to patients who did not (29% vs 6%, p = 0.011). The prognosis for patients with osteosarcoma who had manipulative therapy was significantly poorer than those who had not. Manipulative therapy was an independent factor for survival. This form of therapy may serve as a mechanism to accelerate the spread of tumour cells, and therefore must be avoided in order to improve the outcome for patients with an osteosarcoma.

Hypercalcemia and status epilepticus relates to salmon calcitonin administration in breast cancer.

Calcitonin is currently used to treat hypercalcemia of many clinical types. However, we encountered a woman who suffered severe hypercalcemia and status epilepticus, both of which developed 8 days after the administration of salmon calcitonin for the treatment of breast cancer. When the patient first presented her serum calcium level was 15.5mg/dl, intact parathyroid hormone level 118 pg/ml, calcitonin <2 pg/ml, magnesium 1.2mg/dl, and phosphate 1mg/dl. Her serum calcium level returned to the reference range within 48 h after correction. At follow-up no hypercalcemia had developed, although the patient had received no further treatment for her breast cancer and multiple metastases were subsequently detected. Her hypercalcemia is ascribed to exogenous calcitonin supplementation. These conflicting events may be due to functionally heterogeneous calcitonin receptors or to activation of 1 alpha-hydroxylase by exogenous calcitonin.

The in vitro inhibitory effect of flavonoid astilbin on 3-hydroxy-3-methylglutaryl coenzyme A reductase on Vero cells.

BACKGROUND: Epidemiological studies have shown that hypercholesterolemia is a major risk factor for coronary heart disease. In clinical trials of lipid lowering therapy, 3-hydroxy-3-methylglutaryl Coenzyme A (HMG-CoA) reductase inhibitor has been shown to decrease cardiac events and mortality. Flavonoids are polyphenolic natural antioxidants existing in vegetables, fruits and beverages such as tea and wine. Previous studies have shown that some antioxidants had hypocholesterolemic effect, and flavonoid intake was associated with the decrease of mortality from coronary artery disease. The aim of this study was to evaluate the inhibitory effect of flavonoids on HMG-CoA reductase. METHODS: The methods for analysis of specific inhibitors of mevalonate biosynthesis have been well-established, using Vero cells, a cell line obtained from kidneys of African green monkeys. Flavonoids isolated from different traditional Chinese herbs were dissolved in DMSO and incubated with Vero cells with or without the addition of 1 mM mevalonate or 5 mM sodium acetate in order to observe cell growth for 24 h. RESULTS: Concentrations of 1 mM mevalonate or 5 mM sodium acetate were added into culture medium in order to observe the effect on cell growth. Different concentrations of pravastatin to inhibit cell growth were used as a positive control. About 40 flavonoid compounds were used for study, only one compound, astilbin (belonging to the flavonol group), showed significant inhibition of Vero cell growth. CONCLUSIONS: This study shows that one flavonoid compound, isolated from traditional medicinal herbs, may be an effective HMG-CoA reductase inhibitor which might be developed into a new hypocholesterolemic agent.

Effects of percutaneous electrical stimulation on peripheral nerve regeneration using silicone rubber chambers.

The purpose of this study was to determine whether 0.8-1 mA, 2 Hz of percutaneous electrical stimulation could affect the regeneration of a 10-mm gap of rat sciatic nerve created between the proximal and distal nerve stumps, which were sutured into silicone rubber tubes. Six weeks after implantation, though the group receiving the electrical stimulation had a lower success percentage of regeneration (57%) compared with the controls receiving no stimulation (70%), quantitative histology of the successfully regenerated nerves revealed that the mean values of the axon density, blood vessel number, blood vessel area, and percentage of blood vessel area in total nerve area in the group with the electrical stimulation were all significantly larger than those in the controls (p < 0.05). These results showed that the electrical stimulation could elicit rehabilitating effects on the regenerated nerves.

Effect of acupuncture stimulation on peripheral nerve regeneration using silicone rubber chambers.

The purpose of this study was to determine whether acupuncture could affect the regeneration of a 10-mm gap of rat sciatic nerve created between the proximal and distal nerve stumps, which were sutured into silicone rubber tubes. Empty silicone rubber tubes with no further treatment were used as controls. Six weeks after implantation, the animals received the acupuncture or the electroneedling treatment exhibited a more mature ultrastructural nerve organization with significantly higher numbers in the axon density, the blood vessel area, and the percentage of blood vessel area occupied in total nerve area than the controls. In addition, the electroneedling could combine both the needling and the electrical stimulation to potentiate the nerve-growth promoting effect of the acupuncture treatment. These results showed that acupuncture treatment could elicit positive effects on regenerated peripheral nerves.

A nucleoside-nucleotide mixture may reduce memory deterioration in old senescence-accelerated mice.

We investigated the effects of a mixture of dietary nucleosides and nucleotides (NS + NT) on memory in 1- and 7-mo-old senescence-accelerated mice (SAM). Memory retention was studied with passive avoidance (step-through) and active avoidance (shuttle) tests. For 14 wk, mice in the control groups were fed a 20 g of casein/100 g diet, whereas the NS + NT groups were fed this diet supplemented with a 0.5 g of NS + NT mixture/100 g. All mice were killed at wk 14, and we studied the brain histopathology. Lipofuscin, monovacuoles and multiple vacuoles of various brain regions were measured. Body weight, food intake and ambulatory activity did not differ between the control and NS + NT groups. In old mice, the time of passive avoidance was significantly higher in the NS + NT group than in the control group at d 1 and 7 (P: < 0.05). However, such an effect of NS + NT was not observed in young mice. In the active avoidance test, the incidence of successful avoidance in old mice was higher in the NS + NT group than in the control group at d 1 and 2 (P: < 0.05). The percentages of specific brain cells containing lipofuscin were lower in NS + NT groups than in the control groups in both young and old mice (P: < 0.05). The number of monovacuoles and multiple vacuoles in specific brain regions tended to be lower (P: = 0.1-0.25) in NS + NT than in control groups, with significant differences in the microvacuoles of the middle cortex of young mice and in the multiple vacuoles in the hind cortex of old mice (P: < 0. 05). These results suggest that increased dietary NS + NT may be associated with decreases in the age-induced deterioration of brain morphology and certain memory tasks.

Risk factors for leukoplakia and malignant transformation to oral carcinoma: a leukoplakia cohort in Taiwan.

The effects of betel nut chewing, smoking and alcohol on the occurrence of leukoplakia and its malignant transformation to oral carcinoma were quantified in a leukoplakia cohort (n = 435) from one medical centre between 1988 and 1998 in Taiwan. Sixty oral carcinomas were ascertained in this cohort. A case-control study within the leukoplakia cohort was used to study, risk factors. Using the Weibull survival model, the incidence of malignant transformation of leukoplakia was shown to increase with follow-up years. After adjustment for other relevant risk factors, betel nut chewing (adjusted odds ratio (OR) = 4.59; 95% confidence interval (CI) 1.25-16.86) remained a significant risk factor for malignant transformation. Results from the case-control study showed that the adjusted odds ratios for betel nut chewing and smoking on the occurrence of leukoplakia were 17.43 (95% CI 1.94-156.27) and 3.22 (95% CI 1.06-9.78), respectively. Similar findings were observed when daily frequency and duration were taken into account. This implies that cessation of smoking may reduce by 36% leukoplakia cases, while elimination of betel nuts may prevent 62% of leukoplakia and 26% of malignant transformation to oral carcinoma in the underlying population.

Expression and signal transduction of calcium-sensing receptors in cartilage and bone.

We previously showed that Ca2+-sensing receptors (CaRs) are expressed in chondrogenic RCJ3.1C5.18 (C5.18) cells and that changes in extracellular [Ca2+]([Ca2+]o) modulate nodule formation and chondrogenic gene expression. In the present study, we detected expression of CaRs in mouse, rat, and bovine cartilage and bone by in situ hybridization, immunocytochemistry, immunoblotting, and RT-PCR; and we tested the effects of CaR agonists on signal transduction in chondrogenic and osteogenic cell lines. In situ hybridization detected CaR transcripts in most articular chondrocytes and in the hypertrophic chondrocytes of the epiphyseal growth plate. Expression of CaR transcripts was weak or absent, however, in proliferating and maturing chondrocytes in the growth plate. In bone, CaR transcripts were present in osteoblasts, osteocytes, and bone marrow cells, but rarely in osteoclasts. A complementary DNA was amplified from mouse growth plate cartilage, which was highly homologous to the human parathyroid CaR sequence. Immunocytochemistry of cartilage and bone with CaR antisera confirmed these findings. Western blotting revealed specific bands (approximately 140-190 kDa) in membrane fractions isolated from growth plate cartilage, primary cultures of rat chondrocytes, and several osteogenic cell lines (SaOS-2, UMR-106, ROS 17/2.8, and MC3T3-E1). InsP responses to high [Ca2+]o were evident in C5.18 cells and all osteogenic cell lines tested except for SaOS-2 cells. In the latter, high [Ca2+]o reduced PTH-induced cAMP formation. Raising [Ca2+]o also increased intracellular free [Ca2+] in SaOS-2 and C5.18 cells. These studies confirm expression of CaRs in cartilage and bone and support the concept that changes in [Ca2+]o may couple to signaling pathways important in skeletal metabolism.

Evaluation of a selective screening for colorectal carcinoma: the Taiwan Multicenter Cancer Screening (TAMCAS) project.

BACKGROUND: Although the efficacy of mass screening for colorectal carcinoma (CRC) with a fecal occult blood test has been demonstrated in several randomized trials, a mass screening approach used in countries with intermediate or low incidence of CRC might be costly. Screening high risk people may be an alternative approach, to aid in the prevention of death from CRC. However, the efficacy of CRC screening for high risk people in such countries is uncertain. METHODS: For this study, a multicenter design was devised to identify high risk groups without clinical symptoms related to CRC; these subjects were identified through the study of index cases of CRC in Taiwan. Colonoscopy, in combination with a fecal occult blood test or double-contrast barium enema, was used to screen high risk groups. A total of 8909 subjects were invited to attend screening. Of 8909, 81 with asymptomatic CRC were detected in one-shot screening. Markov models, in conjunction with a simulated approach, were proposed to estimate relevant parameters in relation to disease progression and to assess the effect of the interval between screenings on the efficacy of CRC screening for these high risk groups. RESULTS: The estimated preclinical incidence rate was 0. 00396 (95% confidence interval [CI], 0.002944-0.004985), which was 21 times that reported from a cancer registry in 1994. The simultaneous estimations of mean sojourn time (the average duration between the preclinical screen-detectable phase and the clinical phase) and sensitivity were 2.8 years (95% CI, 2.15-4.30) and 95.0% (95% CI, 24.4-99.9%), respectively. Predictions of mortality reduction for people who received annual, biennial, and triennial screening regimes compared with controls were 26% (95% CI, 0-50%), 23% (95% CI, 0-48%), and 21% (95% CI, 0-47%), respectively. CONCLUSIONS: The efficacy of selective colorectal carcinoma screening has been demonstrated in this study. A high preclinical CRC incidence rate also suggests that such a screening strategy might be cost-effective for countries with intermediate or low incidence of CRC. Methods proposed in this study can be used to evaluate the efficacy of CRC screening in similar screening trials.

Analysis of late-blight disease resistance and freezing tolerance in transgenic potato plants expressing sense and antisense genes for an osmotin-like protein.

The expression patterns of plant defense genes encoding osmotin and osmotin-like proteins imply a dual function in osmotic stress and plant pathogen defense. We have produced transgenic potato (Solanum commersonii Dun.) plants constitutively expressing sense or antisense RNAs from chimeric gene constructs consisting of the cauliflower mosaic virus 35S promoter and a cDNA (pA13) for an osmotin-like protein. Transgenic potato plants expressing high levels of the pA13 osmotin-like protein showed an increased tolerance to the late-blight fungus Phytophthora infestans at various phases of infection, with a greater resistance at an early phase of fungal infection. There was a decrease in the accumulation of osmotin-like mRNAs and proteins when antisense transformants were challenged by fungal infection, although the antisense transformants did not exhibit any alterations in disease susceptibility. Expression of pA13 sense and antisense RNAs had no effect on the development of freezing tolerance in transgenic plants when assayed under a variety of conditions including treatments with abscisic acid or low temperature. These results provide evidence of antifungal activity for a potato osmotin-like protein against the fungus P. infestans, but do not indicate that pA13 osmotin-like protein is a major determinant of freezing tolerance.

Expression of three osmotin-like protein genes in response to osmotic stress and fungal infection in potato.

We have characterized three cDNAs encoding osmotin-like proteins from potato (Solanum commersonii) cell cultures. These cDNAs (pA13, pA35, and pA81) have extensive nucleotide identity in the coding regions but low homology in the 3' non-coding sequences, and may encode three isoforms of potato pathogenesis-related (PR) type 5 proteins. Using gene-specific probes, RNA gel blot analyses showed constitutive accumulation of osmotin-like protein mRNAs in cell cultures, leaves, stems, roots and flowers, with high abundance in the roots and mature flowers. Treatments with abscisic acid (ABA), low temperature, and NaCl increased the accumulation of all three mRNAs in S. commersonii cell cultures and plants grown in vitro. Salicylic acid (SA), and wounding resulted in a moderate increase in the levels of pA13 and pA81 but not pA35 mRNAs. Infection with the fungus Phytophthora infestans activated strong and non-systemic expression of all three osmotin-like protein genes. The accumulation of osmotin-like proteins, however, was detected only in P. infestans-infected tissues but not in plants treated with ABA, SA, NaCl, low temperature, or wounding.

Combined therapy of mitomycin C and Chinese medical herbs on experimental liver cancer.

In this research, ICR male mice were chosen for intrahepatic implantation of sarcoma 180 tumor cells (1 x 10(7)). The mice were randomly divided into various groups 24 hours after implantation. One of the groups was the tumor control, the others were singly or combinedly treated with mitomycin C (MMC) and Shih Chuan-Ta-Pu-Tang (SCTPT) or Shi-Hung-One (SHO). The results revealed that the mortality rate (MR60) in the tumor control was 100% and the mean survival time (MST60) was 21.11 +/- 10.69 days. The best therapeutic effect appeared in the group treated with the combination of MMC and SHO, its MR6o was 55.0% and MST 60 was 47.0 +/- 13.4 days.

The role of atrial natriuretic factor in dehydration and schedule-induced drinking behaviour.

Dehydration-induced drinking (DID) has been defined as a type of homeostatic behaviour controlled by factors related to water balance, whereas schedule-induced polydipsia (SIP) is considered to be a type of nonhomeostatic drinking subsequent to a general increase in motor excitability. In this study, we have attempted to assess the role of atrial natriuretic factor (ANF) in both models to elucidate the mechanisms controlling water intake. Intracerebroventricular injection of ANF (2-8 nmol) caused a dose related suppression of water intake in both DID and SIP, but intravenous injection with a higher dose of ANF (8 nmol) produced a significant suppression of water intake only in DID. Before drinking started, tissue ANF levels increased in atria in both models and decreased in hypothalamus in DID but not in SIP. After 1 hour of drinking, ANF levels decreased in atria in both models and increased in hypothalamus in SIP but not in DID. These results suggest that DID and SIP are different in their thirst regulation, and that the notion that peripheral ANF serves as a humoral factor sending signals to central in the fluid homeostatic control mechanism is questionable.