OBJECTIVETo investigate the distribution characteristics and influencing factors of mental workload of teachers in primary schools.

METHODSNational Aeronautics and Space Administration-Task Load Index (NASA-TLX) was used to assess the mental workload levels for 397 teachers of primary schools in a city.

RESULTSThe mental workload (64.34+10.56) of female teachers was significantly higher than that (61.73+ 9.77) of male teachers (P<0.05). The mental workload (65.66+10.42) of "-35" years old group was the highest. When age of teachers was younger than 35 years old, there was a positive correlation between the mental workload and age (r=0.146, P<0.05). When age of teachers was older than 35 years old, there was a negative correlation between the mental workload and age (r=-0.190, P<0.05). The teachers with higher education level felt higher mental workload (unstandardized coefficients B=1.524, standardized coefficients /=0.111, P<0.05). There was a positive correlation between the mental workload and working hours per day (unstandardized coefficients B =4.659, standardized coefficients/3 =0.223, P<0.001).

CONCLUSIONMental workload of the teachers in primary schools is closely related to age, educational level and work hours per day. Work hours per day is an important risk factor for mental workload. Reducing work hours per day (8 hours) is an effective measure of alleviating the mental workload of teachers in primary schools.

Adolescent ; Adult ; Aged ; Faculty ; Female ; Humans ; Male ; Middle Aged ; Schools ; Stress, Psychological ; epidemiology ; Surveys and Questionnaires ; Workload ; psychology ; Young Adult

OBJECTIVETo establish the scale of the norm of occupational stress on the professionals and put it into practice.

METHODST scores were linear transformations of raw scores, derived to have a mean of 50 and a standard deviation of 10. The scale standard of the norm was formulated in line with the principle of normal distribution.

RESULTS(1) For the occupational role questionnaire (ORQ) and personal strain questionnaire (PSQ) scales, high scores suggested significant levels of occupational stress and psychological strain, respectively. T scores >/= 70 indicated a strong probability of maladaptive stress, debilitating strain, or both. T scores in 60 approximately 69 suggested mild levels of maladaptive stress and strain, and in 40 approximately 59 were within one standard deviation of the mean and should be interpreted as being within normal range. T scores < 40 indicated a relative absence of occupational stress or psychological strain. For the personal resources questionnaire (PRQ) scales, high scores indicated highly developed coping resources. T scores < 30 indicated a significant lack of coping resources. T scores in 30 approximately 39 suggested mild deficits in coping skills, and in 40 approximately 59 indicated average coping resources, where as higher scores (i.e., >/= 60) indicated increasingly strong coping resources. (2) This study provided raw score to T-score conversion tables for each OSI-R scale for the total normative sample as well as for gender, and several occupational groups, including professional engineer, professional health care, economic business, financial business, law, education and news. OSI-R profile forms for total normative samples, gender and occupation were also offered according to the conversion tables.

CONCLUSIONThe norm of occupational stress can be used as screening tool, organizational/occupational assessment, guide to occupational choice and intervention measures.

China ; Female ; Humans ; Male ; Occupations ; Reference Values ; Stress, Psychological ; psychology ; Surveys and Questionnaires ; standards ; utilization

OBJECTIVETo establish the norm of occupational stress on the professionals in Chengdu and Chongqing area.

METHODSAccording to the "Occupation Sorting Canon in the People's Republic of China", the professionals of the above-mentioned area were sorted out and randomly stratified. The normative data were derived from a sample of 2 064 participants. The modified Occupation Stress Inventory Revised Edition (OSI-R) was used to test the targets' occupational stress level (including stressors, strain and coping resources).

RESULTS(1) In these professionals, the sex ratio was about 1:1, average age (36.4 +/- 9.4) years, average length of service (15.9 +/- 10.0) years, 63.07% people were college educated and over 80% married. (2) Descriptive statistics for OSI-R scale scores for the total normative sample, for gender samples and for occupational group samples were modulated. (3) The gender norm showed that there were heavier role overload and stronger occupational strains in males than those in females (P < 0.01). The score of personal resources in the males was not different from that in females (P > 0.05). (4) In terms of different occupations, the scores of occupational role and personal strain among various groups indicated significant differences (P < 0.01). The score of personal resources did not manifest difference (P > 0.05). (5) The major factors influencing OSI-R were sex, occupation and length of service.

CONCLUSIONThe norm established can basically represent the occupational stress on professionals in Chengdu and Chongqing area.

Adult ; China ; Female ; Humans ; Male ; Middle Aged ; Occupations ; Research Personnel ; psychology ; Stress, Psychological ; Surveys and Questionnaires

Background Little is known about the role of dual angiotensin Ⅱ forming pathways during heart failure. In the present study, the changes of chymase and angiotensin converting enzyme (ACE) expressions in the failing hearts of hamsters were analysed.Methods Heart failure was induced by ligation of left anterior descending branch of the coronary artery. Chymase, ACE and angiotensin Ⅱ type 1 receptor (AT1R) mRNA levels were analysed by reverse transcription polymerase chain reaction (RT-PCR). The activities of chymase and ACE were determined by radioimmunoassay (RIA). Myocardial collagen fibre analysis was performed under optical microscope.Results Left ventricular systolic pressure (LVSP) and maximum left ventricular developed pressure increase rate (dp/dtmax, mmHg/s) gradually moved lower at 2, 3, 4 and 8 weeks after operation. On the other hand, left ventricular end-diastolic pressure (LVEDP) increased gradually after operation. Compared with the control group (3.55±0.06, 4.79±0.70), the heart weight/body weight ratio in operation group had increased significantly at 4 weeks and 8 weeks (4.28±0.43, 6.17±0.73) (P<0.01). Collagen staining showed that the quantity of myocardial collagen fibre increased significantly in the operation group. RT-PCR showed that the chymase mRNA level in the operation group was consistently greater than that in the control group. AT1R mRNA level was also increased significantly at 3 weeks and 4 weeks, both being 1.3 times that of the control group (P<0.01), whereas ACE mRNA level was not changed. Higher activity of chymase was detected in operation group, being 4, 8, 13 and 19 times that of the control group at 2, 3, 4 and 8 weeks (P<0.01), respectively. ACE activity was also significantly higher at the same time, being 7, 10, 10 and 3.5 times that of the control (P<0.01). Angiotensin Ⅱ (Ang Ⅱ) level in operation group increased significantly, being 2.5, 2.7, 3.5 and 2 times that of the control group at 2, 3, 4 and 8 weeks, respectively (P<0.01).Conclusions A dual Ang Ⅱ forming pathway from both ACE and chymase in the hamster hearts plays an important role during the development of heart failure. At the decompensatory stage, the reduction of AngII level may be associated with the decrease of ACE activity.

Betacoronavirus ; genetics ; Coronavirus Infections ; diagnosis ; Genetic Variation ; Humans ; Pandemics ; Pneumonia, Viral ; diagnosis ; Real-Time Polymerase Chain Reaction ; methods

OBJECTIVEFor clarifying the situation of the natural infection of rodents having hemorrhagic fever with renal syndrome (HFRS) virus and to type Hantavirus (HV) using molecular technique in Shenzhen city in 2005, and offering guidance for prevention and control of HFRS.

METHODSData on the host animals was collected from the city of Shenzhen. ELISA and indirect immunofluorscent antibody(IFA) test were applied to the specific antibodies against HV in the sera of captured rats. Direct immunofluorscece assay was adopted to determine HFRS antigens and the lung tissues of the HV infected rats were inoculated into Meriones unguiculata to isolate HV. The whole viral RNA was extracted from the lung tissues of the HV infected rats and amplified the partial M fragments with RT-nested-PCR, using the HV genotype specific primers. The amplified genes were then sequenced, and subjected to genotyping and homology analysis.

RESULTS472 rodents were captured from Shenzhen in 2005. Surveillance on rats demonstrated 9.96% rats carrying HV (with a density of 8.25%) and the main host was Rattus norvegicus. In the blood samples of rats, anti-HV IgG antibodies were detectable in 56 cases by IFA, and proved to be positive in 76 cases by ELISA. We successfully isolated a HV strain designated as SZ2083 from Rattus norvegicus for the first time in Shenzhen and was identified to SEO type by RT-nested-PCR. Compared with the coding region of the M gene of HV L99 virus strain, the homologies of nucleotide among them were 97%, but the homology was 76% of the SZ2083 with HTN 76-118 virus strain.

CONCLUSIONResults showed the existence of natural epidemic areas of HFRS in Shenzhen city. Based on the results of sequencing, it is possible that the Seoul strain of HV might be the predominant serotype of virus harbored.

Animals ; China ; epidemiology ; Cities ; Data Collection ; Enzyme-Linked Immunosorbent Assay ; Fluorescent Antibody Technique, Indirect ; Genotype ; Hantavirus ; classification ; genetics ; isolation & purification ; Hantavirus Infections ; epidemiology ; veterinary ; Rats ; virology ; Rodentia ; virology

OBJECTIVETo evaluate the response rate and adverse reactions of exemestane (a new aromatase inactivator) in the treatment of postmenopausal women with advanced breast cancer.

METHODSOne hundred and seventy-three patients with advanced breast cancer entered this study with two patients excluded because of postmenopausal time being less than one year. Therefore, 173 patients could be evaluated for adverse events and 171 patients could be evaluated for efficacy. Exemestane, 25 mg orally daily for 4 weeks as one cycle was given.

RESULTSIn the 171 patients evaluated for efficacy, 4 (2.3%) experienced a complete response (CR) and 40 (23.4%) a partial response (PR), with the overall response rate of 25.7%. Ninety patients (52.6%) had stable disease (SD), with 25 having SD for at least 24 weeks. The clinical benefit (CR + PR + SD > or = 24 weeks) was shown in 69 (40.4%) patients. Progressive disease (PD) was shown in 37 (21.6%) patients. The untreated patients had a higher objective response rate (33.8%) than the retreated ones (18.1%) with significant difference (P = 0.019 7). The response rates for soft-tissue, bone involvement and visceral metastasis were 32.8%, 23.9%, and 12.4% (P = 0.002). There was no significant difference in different ages, time of menopause, disease-free interval or receptor status (P > 0.05). Drug-related adverse events were gastric discomfort (17.9%), malaise (17.9%), nausea (13.9%), hot flushes (11.0%) and dysphoria (5.8%). Other side reactions and abnormal laboratory parameters were observed occasionally which were irrelevant.

CONCLUSIONExemestane can be used to treat postmenopausal women with advanced breast cancer giving only mild adverse reactions which are well tolerated.

Adult ; Aged ; Androstadienes ; adverse effects ; therapeutic use ; Antineoplastic Agents ; therapeutic use ; Aromatase Inhibitors ; Breast Neoplasms ; drug therapy ; Enzyme Inhibitors ; therapeutic use ; Female ; Humans ; Middle Aged ; Postmenopause

OBJECTIVETo provide scientific basis data for revising the national hygiene criteria of "Classification of hazard conditions of productive dust" (GB5817-86).

METHODSThe data of the retrospective study and the field survey data were analyzed with correlation and regression analysis. The product of total dust concentration of respiratory exposure (mg/m(3)), total ventilation during exposure (m(3)/d per psrson), and level of free SiO(2) in dust (%) was the respiratory exposure dose of free SiO(2) (mg per day per person) which was used as dose criteria value of classification of hazard degree of dust.

RESULTSUsing free SiO(2) exposure dose and the dose-effect relationship, the hazard degrees of the dust were divided into 5 grades: 0, I, II, III, IV (0 - 8.0, 8.1 - 12.0, 12.1 - 16.0, > 24.1 mg per day per person).

CONCLUSIONThe exposure dose of free SiO(2) is closely related to the pathogenesis of silicosis. Using the exposure dose of free SiO(2) as the classification indicator of hazard degree of dust is reliable, simple and easy to execute.

China ; Dust ; analysis ; Hazardous Substances ; analysis ; Humans ; Lung ; diagnostic imaging ; pathology ; Occupational Exposure ; standards ; Radiography ; Retrospective Studies ; Safety Management ; standards

BACKGROUNDLittle is known about the role of dual angiotensin II forming pathways during heart failure. In the present study, the changes of chymase and angiotensin converting enzyme (ACE) expressions in the failing hearts of hamsters were analysed.

METHODSHeart failure was induced by ligation of left anterior descending branch of the coronary artery. Chymase, ACE and angiotensin II type 1 receptor (AT1R) mRNA levels were analysed by reverse transcription polymerase chain reaction (RT-PCR). The activities of chymase and ACE were determined by radioimmunoassay (RIA). Myocardial collagen fibre analysis was performed under optical microscope.

RESULTSLeft ventricular systolic pressure (LVSP) and maximum left ventricular developed pressure increase rate (dp/dtmax, mmHg/s) gradually moved lower at 2, 3, 4 and 8 weeks after operation. On the other hand, left ventricular end-diastolic pressure (LVEDP) increased gradually after operation. Compared with the control group (3.55 +/- 0.06, 4.79 +/- 0.70), the heart weight/body weight ratio in operation group had increased significantly at 4 weeks and 8 weeks (4.28 +/- 0.43, 6.17 +/- 0.73) (P < 0.01). Collagen staining showed that the quantity of myocardial collagen fibre increased significantly in the operation group. RT-PCR showed that the chymase mRNA level in the operation group was consistently greater than that in the control group. AT1R mRNA level was also increased significantly at 3 weeks and 4 weeks, both being 1.3 times that of the control group (P < 0.01), whereas ACE mRNA level was not changed. Higher activity of chymase was detected in operation group, being 4, 8, 13 and 19 times that of the control group at 2, 3, 4 and 8 weeks (P < 0.01), respectively. ACE activity was also significantly higher at the same time, being 7, 10, 10 and 3.5 times that of the control (P < 0.01). Angiotensin II (Ang II) level in operation group increased significantly, being 2.5, 2.7, 3.5 and 2 times that of the control group at 2, 3, 4 and 8 weeks, respectively (P < 0.01).

CONCLUSIONSA dual Ang II forming pathway from both ACE and chymase in the hamster hearts plays an important role during the development of heart failure. At the decompensatory stage, the reduction of AngII level may be associated with the decrease of ACE activity.

Angiotensin II ; analysis ; Animals ; Body Weight ; Chymases ; Cricetinae ; Heart Failure ; metabolism ; Male ; Myocardium ; metabolism ; Peptidyl-Dipeptidase A ; genetics ; physiology ; RNA, Messenger ; analysis ; Receptor, Angiotensin, Type 1 ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Serine Endopeptidases ; genetics ; physiology ; Ventricular Function, Left

OBJECTIVETo confirm the diagnosis of multiple carboxylase deficiency (MCD) on the gene level and explore the mutations in Chinese children with MCD.

METHODSBiotinidase (BT) and holocarboxylase synthetase (HLCS) genes were analyzed by PCR and direct sequencing for the 4 BT deficiency patients and 8 HLCS deficiency patients, respectively. The identified mutations in the parents of the patients and 50 normal controls were screened by PCR-restriction fragment length polymorphism and direct DNA sequencing.

RESULTSTotal detection rate of gene mutation is 100% in the 12 children with MCD. Six mutations were detected in the 4 children with BT deficiency, they were c. 98-104del7ins3, c. 1369G>A (V457M), c. 1157G>A(W386X), c. 1284C>A(Y428X), c. 1384delA and c. 1493_1494insT. The last four were novel mutations. Four mutations were found in the 8 children with HLCS deficiency. They were c. 126G>T (E42D), c. 1994G>C (R665P), c. 1088T>A (V363D) and c. 1522C>T (R508W). The last two were hot-spot mutations [75%(12/16)], and c. 1994G>C (R665P) was a novel mutation.

CONCLUSIONThis study confirmed the diagnosis of 12 patients with MCD on the gene level. Six mutations were found in the BT gene and 4 in the HLCS gene, including 5 novel mutations. Two mutations of the HLCS gene are probably hot-spot mutations in Chinese children with HLCS deficiency.

Asian Continental Ancestry Group ; genetics ; Base Sequence ; Biotinidase ; genetics ; Biotinidase Deficiency ; Carbon-Nitrogen Ligases ; deficiency ; genetics ; Case-Control Studies ; Child ; Child, Preschool ; Female ; Humans ; Infant ; Male ; Molecular Sequence Data ; Multiple Carboxylase Deficiency ; genetics ; metabolism ; Mutation