Prevalence of hand dermatitis among hospital nurses working in a tropical environment

BACKGROUND

Although hand dermatitis (HD) is a common occupational problem among hospital nurses, few epidemiological studies of this disease have been conducted in regional areas or tropical environments.

AIM

The aim of our investigation was, therefore, to investigate HD prevalence and correlates among nurses within a unique Australian setting.

DESIGN

We recruited a cohort of 148 female nurses from a large tertiary hospital in north Queensland, Australia, and administered a previously validated, self-reporting HD questionnaire.

RESULTS

The 12-month period prevalence ranged from 43.2% to 59.3%, with an overall group mean of 50.0%. There were no statistically significant differences in HD prevalence between the different hospital wards (p=0.4238). During multiple logistic regression, a history of allergic rash was shown to increase the HD risk 5.5-fold (odds ratio: 5.5, 95% CI: 1.9-19.2, p=0.0038). The risk of HD was also related to increased hand washing frequency (OR 5.8, 95% CI: 1.1-33.4, p=0.0402).

CONCLUSIONS

Overall, the occurrence of HD among Australian nurses was relatively consistent across the various hospital wards. Their 12-month period-prevalence of HD was, however, generally higher than previous reports from other countries.

Haplotype reconstruction from SNP fragments by minimum error correction

MOTIVATION

Haplotype reconstruction based on aligned single nucleotide polymorphism (SNP) fragments is to infer a pair of haplotypes from localized polymorphism data gathered through short genome fragment assembly. An important computational model of this problem is the minimum error correction (MEC) model, which has been mentioned in several literatures. The model retrieves a pair of haplotypes by correcting minimum number of SNPs in given genome fragments coming from an individual's DNA.

RESULTS

In the first part of this paper, an exact algorithm for the MEC model is presented. Owing to the NP-hardness of the MEC model, we also design a genetic algorithm (GA). The designed GA is intended to solve large size problems and has very good performance. The strength and weakness of the MEC model are shown using experimental results on real data and simulation data. In the second part of this paper, to improve the MEC model for haplotype reconstruction, a new computational model is proposed, which simultaneously employs genotype information of an individual in the process of SNP correction, and is called MEC with genotype information (shortly, MEC/GI). Computational results on extensive datasets show that the new model has much higher accuracy in haplotype reconstruction than the pure MEC model.

Musculoskeletal disorders among Chinese medical students

We investigated the prevalence and distribution of Musculoskeletal Disorders (MSD) among Chinese medical students, by means of a questionnaire survey. A total of 207 questionnaires were successfully returned, giving a high response rate of 92.4%. The MSD period-prevalence at any body site was 67.6% in the previous year and 46.9% in the previous week. Almost one-third of them (31.9%), reported an ongoing MSD. By individual body site, the most commonly affected region was the lower back (40.1% in the last year), followed by the neck (33.8%) and shoulders (21.7%). The 7 day period-prevalence also followed a similar descending pattern, being reported by 20.8% at the lower back and 12.1% at both the neck and knees. MSD affected the daily life of students for an average period of 53.8 days, with an average of 6.6 sick days taken from school. Students reporting high mental pressure were 2.9 times more likely to suffer low back pain in the previous 12 months (OR 2.9, 95%CI 1.4-5.9, P=0.0030). Overall, our study suggests that Chinese medical students are at reasonable MSD risk, although it is probably lower than for working physicians. Further investigations are now recommended to elucidate the MSD mechanisms and contributory factors among medical students in China, as elsewhere. A longitudinal study of MSD among a complete group of medical students would be very useful in this regard.

Hand dermatitis among nurses in a newly developing region of Mainland China

Although hand dermatitis (HD) is a common occupational problem for nurses worldwide; few, if any, epidemiological studies of this disease have been conducted in Mainland China. Therefore, we administered a previously validated questionnaire to 306 nurses from a large teaching hospital in Shijiazhuang city, Hebei province. A total of 282 replies were received (92.2%). The 12-month period-prevalence of HD across hospital departments ranged from 14.3% to 23.8%, with an overall rate of 17.7%. Nurses with pre-existing atopic dermatitis were 5.3 times more likely to suffer from HD when compared to nurses without this condition (OR 5.3, 95% CI 2.0-14.2, P = 0.0009). Overall, our study suggests that HD is less common among Chinese hospital nurses when compared to their counterparts around the world. The identification of atopic dermatitis as a significant HD risk factor was, however, consistent with previous research.

Musculoskeletal disorders among professional nurses in mainland China

Although musculoskeletal disorders represent a significant occupational issue for professional nurses worldwide, few epidemiological studies have been conducted in mainland China. Therefore, we investigated 180 nurses (84.1 percent response rate) from a teaching hospital in Shijiazhuang, Hebei Province, using a previously validated, self-reporting musculoskeletal disorder survey. The overall prevalence of musculoskeletal disorders was 70.0 percent, with individual categories reported as follows: lower back (56.7 percent), neck (42.8 percent), shoulders (38.9 percent) and upper back (38.9 percent). Period pain was shown to increase the risk of musculoskeletal disorders 23.8 times (odds ratio [OR] 23.8; 95 percent confidence interval [CI], 4.3-189.1; P = .0008). Excessive mental pressure incurred a 10.5-fold risk increase (OR 10.5; 95 percent CI, 2.2-67.5; P = .0058). Interestingly, occasional consumption of alcoholic drinks reduced the risk of musculoskeletal disorders 10-fold (OR 0.1; 95 percent CI, 0.01-0.4; P = .0046), as did working in the gynecology department (OR 0.1; 95 percent CI, 0.01-0.7, P = .0240). Overall, our study showed that musculoskeletal disorders are common among nursing professionals in mainland China and represent an important occupational issue for this Asian demographic.

Effects of static load on the weight and protein content in the leg muscles of the mouse: a simulation of prolonged standing in the workplace

To simulate the effects of prolonged standing in the workplace on the leg muscles, we subjected mice to centrifugation for 6 wk. The absolute wet weight of leg muscles and internal organs of mice were measured after exposure to 3G by centrifugation for 6 wk and at 2 wk after removal of centrifugation. The weight of the soleus muscle (antigravity muscle) significantly increased after 6-wk exposure to centrifugation, but it decreased to its control weight 2 wk after removal of centrifugation. In contrast, the wet weights of the anterior tibial muscle, liver, and kidneys of mice centrifuged for 6 wk were significantly lower than those of the control mice; they had returned to control levels 2 wk after removal of centrifugation. It was therefore suggested that prolonged standing enlarged the leg muscles but its effect did not last for a long period of time after stopping prolonged standing. Western blot analysis of proteins extracted from the soleus muscle showed that vinculin and alpha-actinin in the centrifuged mice increased slightly, but there were no differences in the heat shock protein 70 (HSP70) and desmin levels between the centrifuged mice and control mice. No difference in HSP 70 suggested that muscle damage did not exist after 6 wk centrifugation.

Health effects of exposure to ethylene glycol monoethyl ether in female workers

Ethylene glycol monoethyl ether (EGEE) is a solvent commonly used in industry. To find the health effect of the solvent exposure in women, we did an investigation on 32 female workers exposed to EGEE in factories manufacturing photopolymer sensitization plate, and 20 subjects working in the same companies without potential exposure to the solvent. The mean age was 35.0 and 33.9 yr in the two groups, respectively. The mean concentration of the urinary metabolite (ethoxyacetic acid) was 120.87 mg/g creatinine (geometric mean) in the exposed group, and 2.71 mg/ g creatinine in the control group. Average RBC count and hemoglobin levels were normal in both groups. However, there were 2 subjects in the exposed group with an RBC count and hemoglobin concentration slightly lower than the standard. Out of 20 controls, 5 subjects reported irregular menstruation, and in comparison, 4 out of 32 exposed females had the same complaint. The most common health complaints were dizziness and swelling of the legs, with the same frequencies seen in both groups. Overall, our study suggests that although female workers were exposed to high concentrations of EGEE, subsequent health problems possibly due to such exposure were not significant.

Epidemiology of hand dermatitis among rural nursing students in mainland China: results from a preliminary study

INTRODUCTION

Although hand dermatitis (HD) is known to affect nursing students worldwide, no studies of this disease have yet been conducted in China. Similarly, rural populations are often neglected in international research.

METHODS

A preliminary study of female students from both grades of a hospital-based nursing school was conducted in Hebei Province, China, approximately 280 km south of Beijing. There were 27 students from the 2nd year of the course (47.4%) and 30 students from the 3rd year (52.6%). The study protocol involved an anonymous questionnaire distributed to a convenience sample of both grades from the nursing school. Statistical differences in prevalence by year of study were calculated using Fisher's exact test for discrete variables and One-way Analysis of Variance (ANOVA) for continuous variables. Statistical associations between HD and demographic items were investigated using the chi2 test. Where statistical association with HD were identified, simple logistic regression was also performed to establish a basic risk magnitude. Results were compared with similar populations of student nurses from previous studies in Australia, Japan, Denmark, the Netherlands and Germany.

RESULTS

HD prevalence fell from 29.6% in the 2nd year to 13.3% in the 3rd year and averaged 21.1% across both grades. Systemic allergic disease among family members was found to be statistically associated with HD (p < 0.05). Overall, our preliminary study showed that HD probably affects Chinese nursing students at rates similar to that of their Japanese counterparts, but at a higher rate than students in other investigations from Germany, Holland and Australia. The identification of familial allergic disease as a possible risk factor for HD was also novel.

CONCLUSION

The investigation was conducted as a preliminary investigation, and as such, our results need to be treated with caution. Further research is recommended to more carefully elucidate the prevalence of HD among larger groups of Chinese nursing students.

Imbalance of testosterone level in male offspring of rats perinatally exposed to bisphenol A

The purpose of this study was to investigate whether exposure to bisphenol A (BPA) through the placenta and milk has any effect on the reproductive system in male offspring. Pregnant rats were treated with BPA at 0, 4, 40 and 400 mg/kg body weight, from gestation day 6 through lactation day 20 by gavage. Plasma testosterone concentrations in offspring at 9 weeks old were significantly high in BPA groups as compared with those of the control. At the age of 36 weeks the hormone concentrations showed an increase in a dose-dependent manner, although without statistical significance. Testosterone content in testes showed a similar tendency to that in plasma, though statistically insignificant. Little alteration in testes weight was seen in BPA-exposed offspring. There was no remarkable change in plasma concentrations of luteinizing hormone and follicle-stimulating hormone at 9 weeks old. The pathway of E2 (17beta-estradiol) formation from testosterone seemed not to be affected by BPA. The results indicate that exposure to BPA during the perinatal period has a significant effect on testosterone homeostasis in male offspring of rats.

Effects of in utero and lactational exposure to bisphenol A on somatic growth and anogenital distance in F1 rat offspring

Bisphenol A (BPA), a xenoestrogen, has been reported to mimic the actions of estrogen or to affect the endocrine glands in vivo and in vitro. In this study, we examined whether in utero and lactational exposure to BPA altered the somatic growth and anogenital distance (AGD) of F1 offspring (1, 3, and 9 weeks of age) in vivo in rats. Dams were orally administered with various doses of BPA (0, 4, or 40 mg/kg body weight (BW)/day) from gestation day (GD) 6 through postnatal day (PND) 20. There were no significant changes in body weight, liver weight, kidneys weight, testes weight, AGD, the ratio of AGD to BW, or the ratio of AGD to the cube root of BW in BPA exposed pups compared to the vehicle-exposed control. This suggests that prenatal and postnatal exposure (indirect exposure) to BPA (4-40 mg/kg/day, GD 6-PND 20) does not affect on somatic growth or AGD of F1 generation of male and female rats.

The second largest subunit of mouse DNA polymerase epsilon, DPE2, interacts with SAP18 and recruits the Sin3 co-repressor protein to DNA

DNA polymerase epsilon is essential for cell viability and chromosomal DNA replication in budding yeast. In addition, DNA polymerase epsilon may be involved in DNA repair and cell-cycle checkpoint control. The enzyme consists of at least four subunits in mammalian cells as well as in yeast. The largest subunit of DNA polymerase epsilon is responsible for polymerase activity. To date, the functions of the other subunits have remained unknown. With a view to elucidating the functions of the second largest subunit of mouse DNA polymerase epsilon (DPE2), yeast two-hybrid screening was performed to identify mouse proteins that interact with this subunit. SAP18, a polypeptide associated with co-repressor protein Sin3, was identified as an interacting protein. A part of the N-terminal region of DPE2 (comprising amino acids 85-250) was found to be responsible for the interaction with SAP18. The interaction induced repression of transcription in reporter plasmid assays, which was inhibited by trichostatin A. These results indicate that DPE2 may recruit histone deacetylase (HDAC) to the replication fork to modify the chromatin structure.

Effects of aldehyde dehydrogenase-2 genetic polymorphisms on metabolism of structurally different aldehydes in human liver

Genotype analysis of the aldehyde dehydrogenase (ALDH)-2 gene was performed using an improved simplified method, and effects of the genotype on the metabolism of a variety of aldehydes in different fractions of human liver cells were investigated. The effects of sex, aging, smoking, drinking alcohol, liver function, and various drugs on ALDH activity were also analyzed. Of the 39 subjects, eight were heterozygotes of the wild (ALDH2*1) and mutant (ALDH2*2) alleles, and the others were homozygotes of the wild allele. ALDH activity toward acetaldehyde in liver mitochondria from subjects with a mutant allele was less than 10% of that with two alleles of wild-type, and the activities toward formaldehyde, propionaldehyde, n-butyraldehyde, capronaldehyde, and heptaldehyde were also significantly lower in the ALDH2*1/*2 rather than ALDH2*1/*1 group. However, the metabolism of octylaldehyde, decylaldehyde, retinaldehyde, benzaldehyde, 3-hydroxybenzaldehyde, and 2,5-dihydroxybenzaldehyde was similar in the two genotypes. Changes in activity in the cytosolic fraction were similar to those in mitochondria. There was no significant difference in ALDH activity in microsomes between the two groups. Total activities of ALDH toward acetaldehyde and other short-chain aliphatic aldehydes in supernatant fractions of homogenized liver were affected in a manner similar to that in mitochondria. Our results suggest that the single nucleotide polymorphisms of the ALDH2 gene only alter the metabolism of aldehydes with a short aliphatic chain. Furthermore, sex, drinking alcohol, and smoking had little effect on ALDH activity, although the activity in elderly individuals tended to be lower albeit statistically insignificant.

The eco-origins, actions and demonstration roles of Beijing Green Olympic Game

The 29th Olympic Game will be held in Beijing in 2008. It will be a green game to promote sustainable development of men, cities and regions through ecological development advocating "man and nature be in one". "Eco" here means a process, a driving force, an action, a culture and a kind of vitality leading to sustainable development. It is a mechanism embodying the Olympic spirit of competition, cooperation and self-reliance. The paper explained the ecological significance, connotation and objectives of Beijing Green Olympic Game. Ten major ecological heritages of Beijing have been investigated including ecologically sound landscape, culture, transportation, physical exercise, health care, sanitation, food, family relationship, agriculture, and human ecological totality. To preserve or restore the above mentioned old tradition, a green Olympic action plan has been made out in Beijing initiated by NGOs, supported by entrepreneurs and coordinated by government agencies. Four kinds of eco-engineering have been planned for blue sky, clean water, green land and eco-city development. The demonstration role of Beijing Green Olympic Game to developing regions and countries is also discussed.

Effects of toluene on regulation of adenylyl cyclase by stimulation of G-protein-coupled receptors expressed in CHO cells

We determined the effects of toluene exposure on activation or inhibition of adenylyl cyclase by stimulating human beta2-adrenergic receptors (beta2-AR) and muscarinic acetylcholine receptor (mAChR) m2 subtypes, respectively, expressed in CHO cells. The formation of cAMP via beta2-AR stimulation was slightly but not significantly facilitated in the presence of 3.7 microM toluene. On the other hand, the inhibition of adenylyl cyclase by 10 microM of carbamylcholine stimulation of mAChR m2 subtypes was attenuated in the presence of toluene. These results strongly suggest that toluene affects activation of Gi rather than Gs.

Different change patterns of the isozymes of cytochrome P450 and glutathione S-transferases in chemically induced liver damage in rat

In this experiment, we studied the different changes in activities and protein levels of each subform of hepatic cytochrome P450 and glutathione S-transferase (GST), in chemical-induced liver injury in rats. Rats were administered 1,1-dichloroethylene (DCE), allyl alcohol (AA), bromobenzene (BB) and N,N-dimethylformamide (DMF) p.o. once every two days for 7 times, and decapitated 18 hr after the last administration. DCE and AA showed stronger hepatic toxicity than BB and DMF, as serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were higher in DCE and AA treated rats than in BB and DMF groups. Anti-cytochrome P450 inhibitable activity of toluene metabolism and/or immunoblot analysis showed that CYP2E1 and CYP2B1/2 were induced by BB and DMF, but not by the other two chemicals; CYP2C11 was greatly decreased by all of the four toxicants; and CYP1A1/2 was slightly reduced by the four treatments. These changes were reflected in testosterone metabolism. Formation of 6 beta- and 7 alpha-hydroxytestosterone from testosterone was enhanced only in DMF-treated rats, whereas that of 2 alpha- and 16 alpha-hydroxytestosterone was reduced by all of the four chemicals. Serum GST activity was increased only in BB and DMF treated rats, but liver cytosolic GST activity was enhanced by all of the four hepatotoxicants, with higher values in BB and DMF groups than in DCE and AA groups. Immunoblot analysis demonstrated that GST Yp was induced by BB and DMF treatments, and Ya and Yc were increased only by BB. GST Yk and Yb1 were not affected by the treatments. The different change patterns of enzymes by a specific toxin and the similar modifying effect on a specific enzyme by different toxins were discussed in relation to the liver damage and to the heterogeneous distribution of enzymes in liver.

Apoptosis induced by zinc deficiency in rat osteoblast: possible involvement of protein kinase C

Rat osteoblasts were isolated from the 21-day fetal rat calvarias. The cells were grown in DMEM plus 10% FBS, and were treated for 24 h. with 10 mumol/L TPEN or 10 mumol/L TPEN supplemented with 10 mumol/L Zn2+. Apoptosis of osteoblasts were measured by flow cytometry, electron microscopy and DNA fragmentation analyzed by gel electrophoresis. In addition, IP3 production and PKC activity were measured in order to show whether they are involved in apoptosis in osteoblast induced by zinc deficiency. The results showed that 10 mumol/L TPEN could induce apoptosis in osteoblast in 24 h. But cells treated with 10 mumol/L TPEN supplemented with 10 mumol/L Zn2+ showed no apoptotic changes in 24 h. TPEN significantly reduced the formation of IP3 and PKC activity after 24 h incubation. No differences were observed between the cells treated with TPEN supplemented with Zn2+ simultaneously and the untreated cells. It can be inferred that apoptosis induced by zinc deficiency may be due to the decreased activity of PKC which is impaired by reduced formation of IP3.

Trichloroethylene inhibits aldehyde dehydrogenase only for aliphatic aldehydes of short chains in rats

The effects of trichloroethylene (TCE) administration on aldehyde dehydrogenase (ALDH) and cytochrome P450 isozymes were studied in rats and compared with those of methanol. Intragastric administration of TCE to rats at 0.05 or 0.2 ml/kg for 1 week significantly inhibited ALDH activity for aliphatic aldehydes of short chains in the mitochondrial and cytosolic fractions of rat liver, respectively, but had no effect on the activity for long chain aliphatic aldehydes. ALDH activity catalyzing the metabolism of some aromatic aldehydes was even induced by TCE. Microsomal ALDH activity was not decreased by TCE treatment. A kinetic study showed that the low-Km isozyme of ALDH for propionaldehyde in mitochondrial and cytosolic fractions was inhibited by TCE treatment. Addition of TCE, trichloroethanol or trichloroacetic acid to the in vitro assay system did not affect the activity for acetaldehyde, but chloral hydrate at 0.02 mM decreased the activity by 42 and 35% in cytosol and the 700 x g supernatant, respectively. Methanol treatment, on the other hand, had no effect on any ALDH activity. Both TCE and methanol significantly induced CYP2E1 in rat liver. The combined effects of TCE on ALDH and cytochrome P450 may account for the degreasers' flush. Exposure to TCE and methanol may result in a change in the metabolism and toxicity of other chemicals.

The effectiveness of dietary instruction in obese school children of southern Taiwan

The purpose of this study is to evaluate the short-term effectiveness of a weekly dietary instruction program to reduce obesity in elementary school children. A total of 140 third- to sixth-grade overweight children and 130 height- and age-matched overweight children were selected from two elementary schools in Kaohsiung. The primary inclusion criterion was a Rohrer's Index [RI = weight (kg)/height (cm)3 x 10(7)] greater than 150. The anthropometric measurement was performed on both the group receiving instruction and the group not receiving instruction. Biomedical monitoring of the students state of health, assessments of their nutritional knowledge, attitude and practice (K.A.P.) before and after the thirteen-week instruction were compared in the instruction group. After completion of the instruction program, a significant reduction of RI values (177.2 +/- 18.3 vs. 169.4 +/- 20.1, p < 0.01), and a significant increase in body height (144.9 +/- 7.7 cm vs. 146.7 +/- 7.7 cm, p < 0.01), with no change in body weight (54.5 +/- 11.3 kg vs. 54.3 +/- 11.3 kg) were found in the group receiving instruction. Some of the anthropometric parameters of obesity were also significantly improved. Reduction of total cholesterol and serum Glutamic Oxaloacetic Transaminase (GOT)/Glutamic Pyrvic Transaminase (GPT) levels were also observed; the later phenomena were interpreted as an improvement in the fatty metamorphosis of the liver, which usually accompanies obesity. A significantly increased nutrition knowledge and change to more healthy dietary behavior were also found in students who finished the instruction program. This reduction was a measure of the effectiveness of weekly dietary instruction sessions. An increase in NSQ scores indicated improved nutritional knowledge and behavior. Through the implementation of weekly nutritional instruction, a decrease in RI can be achieved in a thirteen-week period. We propose that frequent nutritional education should be part of the curriculum of elementary school children in order to prevent obesity-related diseases.

[Application of mouse limb bud culture to study the influence of zinc on teratogenesis induced by cadmium]

In this study, an in vitro method of mouse limb bud culture in self-made rotator with continuous supplementation of gas mixture was employed in studying the teratogenic potential of cadmium and the influence of zinc on the teratogenesis induced by cadmium. Image analysis on the area and the form of the bone analgen of the cultured limb was used to evaluate quantitatively their teratogenic potentials. Different amounts of cadmium were directly added to culture medium. As cadmium concentrations were increased from 0.1 to 1.0 microgram/ml, the degree of morphogenetic differentiation and the area of the bone anlagen of limbs culture were significantly decreased. The paws and long bones were affected seriously. Cadmium had a greater effect on chondrogenic tissue than on soft tissue. Then various levels of Zn, together with cadmium (1.0 microgram/ml medium), were added into the culture media. As Zn concentrations increased from 1.0 to 10.0 micrograms/ml, the degree of morphogenetic differentiation and the area of cartilaginous bone anlagen of limbs culture were improved or increased. The long bones were better ameliorated as compared with the paw.

A survey of social nutrition status of the elderly in the urban area of Chengdu, Sichuan Province

The social nutrition status was investigated among 246 subjects aged 60-90 living at three urban communities in Chengdu of Sichuan Province. The questionnaire was designed to evaluate socio-demographic background, the subjects' nutrition knowledge, and the support systems for geriatric nutrition. Fasting venous blood was collected for the analysis of biochemical parameters. Blood pressure, bone mineral contents (BMC), body weight (BW) and body height (BH) were measured at the same time. Only 49.7% of the subjects correctly answered four basic questions on nutrition. Food patterns for the elderly were simple and modest. Several nutrition-related disorders for the elderly were including high systolic blood pressure (44.6%), hypertriglyceridemia (25.9%), high diastolic blood pressure (25.1%), obesity (24.5%), high PBG (20.6%), emaciation (19.9%), high FBG (17.9%) and osteoporosis (16.8%). These data indicate that the support systems for the geriatric nutrition will have to be improved.

Cytochrome P450 isozymes responsible for the metabolism of toluene and styrene in human liver microsomes

1. Cytochrome P450 isozymes from Asian (31 Chinese subjects) and Caucasian (14 Finnish subjects) livers were examined for their roles in the metabolism of toluene (rates of benzyl alcohol, o- and p-cresol formation) and styrene (rates of styrene glycol formation). 2. For toluene, the overall rate of metabolism was higher in samples from Finnish than from Chinese subjects. At 0-20 mM toluene, the rate of o-cresol formation was significantly higher in Finnish microsomes than in Chinese ones. The formation rates of benzyl alcohol and p-cresol in Finnish samples were also higher than those of Chinese samples, but only at a high substrate concentration (5.0 mM). For styrene metabolism, the Chinese liver microsomes showed higher metabolic rates than the Finnish ones at 0.085 mM styrene, but not at the higher substrate concentration. 3. Mean expression levels of immunochemically detected CYP1A2/1 and CYP2B6 were almost 3-fold higher in Finnish microsomes, whereas CYP2E1 was 1.7-fold higher in Chinese samples. 4. Correlation analysis showed that CYP2E1 (benzyl alcohol formation) and CYP1A2/1 (o-cresol formation) contributed to the metabolism of toluene at the low substrate concentration, whereas CYP2C8 was the form more actively involved at the higher toluene concentrations. At the higher concentration (1.8 mM) of styrene, CYP2B6 was most active isozyme to catalyse the formation of styrene oxide from styrene. 5. These results suggest that CYP2E1 and CYP1A2/1 are the main isoforms responsible for the metabolism of toluene at low substrate concentrations in human liver microsomes, CYP2E1 at low styrene concentration, and CYP2C8 and CYP2B6 at high concentrations of toluene and styrene respectively.

Toluene metabolism by cDNA-expressed human hepatic cytochrome P450

The metabolism of toluene in human liver microsomes and by cDNA-expressed human cytochrome P450s (CYPs) was investigated. Toluene was metabolized mainly to benzyl alcohol and slightly to o- and p-cresol by human liver microsomes. Formation of o-cresol was elevated in microsomes from human livers derived from cigarette smokers, but the induced CYP isoforms were not clear. Of the eleven human CYP forms studied, CYP2E1 was the most active in forming benzyl alcohol, followed by CYP2B6, CYP2C8, CYP1A2, and CYP1A1, in that order. The activities of CYP2A6, CYP2C9, CYP2D6, CYP3A3, CYP3A4, and CYP3A5 were negligible. In addition, CYP2B6 and CYP2E1 catalyzed the formation of p-cresol (11-12% of total metabolites), and CYP1A2 catalyzed the formation of both o-(22%) and p-cresol (35%). The relationship between the amino acid sequence of rat CYP2B1 cDNA and the activity for toluene metabolism was investigated using variants, because of great differences in the forming of toluene ring products between CYP2B1 and CYP2B6. These results suggest that the structure of CYP2B1 at the site of Leu 58 rather than Ile-114 and Glu-282 plays an important role in the formation of toluene ring products, whereas in CYP2B1 Ile-114 plays an important role in the formation of benzyl alcohol. These results may explain, in part, the lower activity of CYP2B6, which has Phe at position 58 of the protein, for toluene ring oxidations than that of CYP2B1.

Clinical trial of low-dose rHuG-CSF in neutropenic cancer patients following anti-cancer chemotherapy

Low-dose, subcutaneous recombinant human granulocyte colony-stimulating factor (rHuG-CSF, Lenograstim) was administered to 40 cancer patients (17 men, 23 women) enrolled from two medical centers to verify its clinical effectiveness and safety. The patients' mean age was 50.3 +/- 14.9 years. In this study, there were 20 patients with non-Hodgkin's lymphoma, 10 with breast cancer and 10 with various other solid tumors. The patients first received a course of chemotherapy without rHuG-CSF (control cycle). All patients had at least one episode of neutropenia or leukopenia during the control cycle. rHuG-CSF (2 micrograms/kg/day) was given subcutaneously for 10 days during the study cycle starting on the fourth day of chemotherapy. The nadirs of absolute neutrophil counts (ANC) were 1.8 +/- 0.25 x 10(9)/L and 0.27 +/- 0.05 x 10(9)/L for the rHuG-CSF cycle and pre-rHuG-CSF control cycle, respectively. The number of days of ANC < 1 x 10(9)/L were 1.03 +/- 0.29 and 7.38 +/- 0.58 for rHuG-CSF and control cycles, respectively. The duration from nadir to recovery of ANC (> or = 2 x 10(9)/L) was 9.68 +/- 1.15 days in the rHuG-CSF cycle, vs 22.53 +/- 1.03 days in the control cycle (p < 0.0001). No patient withdrew from the study. Adverse events were mild, with 12.5% to 40% of patients developing myalgia, general malaise, back pain, anorexia or fever. These side-effects were tolerable in all cases. The biochemical abnormalities were subtle and negligible. rHuG-CSF 2 micrograms/kg/day given subcutaneously for 10 days beginning on the fourth day of chemotherapy is very effective (90%), safe and convenient.

Expression of cytochrome P450s and glutathione S-transferases in human esophagus with squamous-cell carcinomas

In order to clarify the expression of cytochrome P450 and glutathione S-transferase in human esophagus, 41 samples of human esophagus with squamous-cell carcinoma were investigated by immunoblot analysis and enzyme assays. Cytochrome P450 1A2/1 was clearly expressed in microsomes, and the amount in samples with tumorous tissue was significantly greater than that in samples without tumourous tissues or in liver; cytochrome P450 2B6 and 3A4/3 were expressed polymorphically. Aryl hydrocarbon hydroxylase activity was detected in microsomes and was greater in samples from smokers than non-smokers. Patients who both smoked and drank alcohol, however, had activity similar to that of patients without these habits. Glutathione S-transferase M1 and A1/2 protein existed polymorphically in cytosol, and glutathione S-transferase P1-1 was detected in all samples. The frequency of expression of the glutathione S-transferase A1/2 protein was greater in patients with M1 protein than in those without; no difference in the expression was seen for glutathione S-transferase P1-1. Neither smoking nor drinking influenced the expression or activity of glutathione S-transferase. Our data support the idea that some carcinogens can be directly activated or inactivated in human esophageal epithelium.

[The participation of physical activity and its associated factors in the elderly]

The purpose of this study was to explore the participation of physical activity and its related factors in the elderly in the community. Five hundred elderly ( > or = 65 yrs) living in the San-Min district of Kaohsiung city was taken as study subjects. A structured questionnaire was used to gather data including the following items: (1) the participation of physical activity (2) modifying factors: demographic data, biological characteristics, previous experience in exercise and exercise knowledge (3) cognitive-perceptual factors: perceived health status, perceived self-efficacy, perceived benefits and perceived barriers to exercise (4) cues to action. The results showed 19.2% of the elderly never exercised, 15.9% had exercised previously but not now, 20.4% exercised intermittently, 1% exercised only on holidays and 43.8% exercised regularly. Within the elderly who exercised regularly, 89.2% exercised more than three times a week and at least 20 minutes each time, walking was the most popular exercise pattern. The participation of physical activity had significant relationship with modifying factors, cognitive-perceptual factors and cues to action. After logistic stepwise multiple regression, those who totally self-care, without a history of exercise injury during youth, male, higher perceived self-efficacy score, lower perceived barriers score and those with higher cues to action score tended to exercise regularly.