Decrease of suppressor-inducer (CD4+ CD45RA) T lymphocytes and increase of serum immunoglobulin G due to perceived job stress in Japanese nuclear electric power plant workers

To clarify the effects of perceived job stress on the immune system, a cross-sectional study was conducted in 116 male Japanese workers of a nuclear electric power plant (age, 20 to 39; mean, 31 years). Perceived job stress, i.e., psychological job demand, job control, worksite social support, and job strain, was assessed by means of the Japanese version of the Job Content Questionnaire. The job strain score was calculated as the ratio of the job demand score to the job control score. Blood samples were taken from all workers, and numbers of T and natural killer cell subpopulations, B lymphocytes, total lymphocytes and white blood cells, and serum concentrations of immunoglobulins (IgG, IgM, IgA, IgE and IgD) in their blood were measured. The workers were divided into higher and lower strain groups according to their job strain scores. The number of CD4+ CD45RA+ T lymphocytes in the higher strain group having the job strain score of 0.5 or more (41 workers) was significantly smaller than that in the lower strain group having the score of less than 0.5 (75 workers). In contrast, the serum IgG concentration in the former group was significantly higher than that in the latter group (analysis of covariance with age and smoking as covariates). Also, the numbers of total CD4+ T and total T (CD3+) lymphocytes and of white blood cells in the former group were significantly smaller than those in the latter group. After controlling for age and smoking by the partial correlation coefficient in all 116 workers, the number of CD57+ CD16+ natural killer cells was inversely correlated with job demand and with job strain; the number of CD8+ T lymphocytes was positively correlated with worksite social support; and serum IgG and IgM concentrations were positively correlated with job strain. It is suggested that higher job strain decreases the number of CD4+ CD45RA+ T lymphocytes in male Japanese workers but increases serum IgG concentrations.     

Increase in Memory (CD4+CD29+ and CD4+CD45RO+) T and Naive (CD4+CD45RA+)T-Cell Subpopulations in Smokers

To examine the effects of smoking on lymphocyte subpopulations, we measured the following cell subpopulations: CD4+ T-cell subpopulations (i.e., CD4+CD29+, CD4+ CD45RO+, and CD4+CD45RA+ cells); CD8+ T-cell subpopulations (i.e., CD8+CD11a+ and CD8+CD11b+ cells); and natural killer cell subpopulations (i.e., CD16+CD57-, CD16+CD57+, and CD16-CD57+ cells). We measured these subpopulations, together with total CD4+ T, total CD8+T, total CD3+T, B (CD19+), and total lymphocytes, in 10 male heavy smokers, 38 male light-to-moderate smokers, and 33 male nonsmokers. The mean ages were 30 y, 31 y, and 32 y, respectively, and ages did not vary significantly among the smokers. CD4+CD29+ and CD4+CD45RO+ (memory T) cells in heavy smokers were significantly more numerous than those in light-to-moderate smokers and nonsmokers. Also, these memory T-cell subpopulations were significantly more numerous in light-to-moderate smokers than in non-smokers. The number of CD4+CD45RA+ (naive T) cells was significantly larger in heavy smokers than nonsmokers; numbers of CD4+CD45RO+ T and CD4+CD29+ T cells (memory T cells) were significantly correlated with daily cigarette consumption. Numbers of CD3+ T, CD4+ T, CD19+ B, and total lymphocytes in heavy smokers were significantly larger than in nonsmokers. There were significantly more CD3+ T, CD4+ T, and total lymphocytes in light-to-moderate smokers than in nonsmokers. The numbers of CD4+ T lymphocytes in heavy smokers were significantly larger than in light-to-moderate smokers. Perhaps CD4+ T cell subpopulations, especially memory T cells, are most susceptible to the effects of smoking on lymphocyte sub-populations.     

Effects of smoking and Japanese cedar pollinosis on lymphocyte subpopulations

Approximately 10-30% of the Japanese population suffer from Japanese cedar (Cryptomeria japonica) pollinosis in the spring. To date, the effects of this pollinosis on lymphocyte subpopulations have not been examined epidemiologically. To examine the effects of smoking and Japanese cedar pollinosis on lymphocyte subpopulations, we used flow cytometry to measure CD4+ and CD8+ T-lymphocyte subpopulations, natural-killer cell subpopulations, B(CD19+) lymphocytes, and total lymphocytes in 61 smokers and 51 nonsmokers. Some of these individuals had histories of pollinosis during November 1993-an off-season for Japanese cedar pollination. Our findings suggested that (a) CD4+ T-lymphocyte subpopulations (i.e., CD4+CD29+, CD4+CD45RA+, and CD4+ CD45RO+ cells) together with total CD4+ T, total T, and total lymphocytes, were increased by the effects of smoking; (b) CD8dim+CD11a+T, and CD8+CD11bt, and CD57+CD16+ natural killer cells, together with total CD8+CD11 a+ T and total CD8+ T lymphocytes, were increased by the effects of pollinosis on smokers, even though no lymphocyte subpopulations were increased by only the pollinosis effects; (c) CD4+CD29+T and CD8dimCD11a+ T lymphocytes were increased by the effects of smoking on pollinosis, and (d) CD4+CD29+ T and CD4+CD45RO+ T lymphocytes, CD8dim+CD11 a+ T, and CD8+CD11b+ T lymphocytes and CD57+CD16+ natural killer cells, together with total CD4+ T, total T (CD3+), total CD8+CD11a+, total CD8+ T, and total lymphocytes, were increased by the combined effects of smoking and pollinosis.     

Decreases in CD8+ T, naive (CD4+CD45RA+) T, and B (CD19+) lymphocytes by exposure to manganese fume

To examine the effects of exposure to manganese (Mn) on the cellular and humoral immune system in men, T lymphocyte subpopulations, B (CD19+) lymphocytes, natural killer (NK) cells, and serum immunoglobulins (i.e., IgG, IgA and IgM) together with total T (CD3+) lymphocytes and total lymphocytes were measured in blood samples from 21 welders mainly exposed to Mn fume with blood Mn (BMn) concentrations of 0.6-2.3 (mean 1.4) microg/dl and 21 healthy controls working in the same factory (BMn concentrations: 0.7 to 1.7, mean 1.1 microg/dl). The workers engaged in welding for 6 to 36 (mean 17) yr. All the study subjects were divided into 3 equally sized groups (n=14 for each group) according to BMn concentrations. Numbers of CD8+ T, total T (CD3+), B (CD19+), and total lymphocytes were significantly lower in high-BMn group than those in low-BMn group; the numbers of CD8+ T lymphocytes were significantly lower in moderate-BMn group compared to low-BMn group. After adjusting for age and smoking, significant inverse correlations between BMn concentrations and CD4+CD45RA+ T, CD4+ T, CD8+ T, CD3+ T, and total lymphocytes were found. We conclude that T lymphocytes, especially CD8+ and CD4+CD45RA+ T lymphocytes, as well as CD19+ B lymphocytes are affected by exposure to Mn fume.     

Effects of occupational metallic mercury vapour exposure on suppressor-inducer (CD4+CD45RA+) T lymphocytes and CD57+CD16+ natural killer cells

Objectives: To examine the effects of metallic mercury vapour on the cellular and humoral immune system. Methods: We measured T lymphocyte and natural killer (NK) cell subpopulations, B lymphocytes, and serum immunoglobulins (i.e. IgG, IgA and IgM) together with total T (CD3+) lymphocytes and total lymphocytes in blood samples from 20 male, fluorescent-lamp makers (mercury workers) and the same number of gender-, age- and smoking-matched controls. Urinary concentrations of inorganic mercury (UHg) in the 20 workers ranged from 1.8 to 163.5 (mean 44.8) μg/l. They had been exposed to mercury vapour for 4 to 62 (mean 31) months. Results: Numbers of CD4+CD45RA+ (suppressor-inducer) T lymphocytes and total CD4+ T lymphocytes in the mercury workers were significantly smaller than those in the controls (paired-sample t-test, P < 0.01). The number of CD57+CD16+ NK cells was inversely correlated with UHg. Conclusion: It is suggested that numbers of CD4+CD45RA+ T lymphocytes and CD57+CD16+ NK cells are inversely affected by exposure to metallic mercury vapour in workers, with an average urinary inorganic mercury concentration of 45 μg/l being found. Received: 7 September 1999 / Accepted: 6 May 2000     

低水平长期铅接触对作业工人淋巴细胞亚群的影响

[目的]检测淋巴细胞亚群以探讨低水平长期铅接触对免疫系统的影响。[方法]对44名铅作业工人和34名对照者采用流式细胞仪进行淋巴亚群分型及用酶联免疫法检测IgE,检测项目包括：CD3、CD4、CD8、CD45RO、CD19、HLADR、IgE。[结果]CD4^ CD45RO^ 、CD3^-HLADR^ 淋巴细胞铅接触组明显低于对照组,CD19^ 、CD4^ CD45RO^-、CD3^ HLADR^ 淋巴细胞和IgE两组间没有显著性差异。[结论]长期低水平铅接触可能影响T淋巴细胞亚群,从而影响细胞免疫功能。     

Increase in CD57 + CD16 - lymphocytes in workers exposed to benzidine and beta-naphthylamine: assessment of natural killer cell subpopulations

Previously, we found a decrease in CD4+CD45RA+T lymphocytes in workers exposed to the aromatic amines (AAs) [benzidine (BZ) and beta naphthylamine (BNA)]. For further investigation of the effects of AAs on lymphocyte subpopulations, we measured natural killer (NK) cell subpopulations using two-color staining with anti-Leu7 (CD57) and anti-Leu11 (CD16) monoclonal antibodies in peripheral blood in 78 male dyestuff workers. The workers had been exposed to AAs before 1972 at a chemical plant, either in the production of AAs (40 workers, high-exposure group) or in other work that involved handling dye-stuffs (38 workers, low-exposure group). The controls were 30 “healthy” male volunteers without a history of occupational exposure to AAs or hazardous chemicals. The number of CD57+CD16-cells in the high-exposure group was significantly higher than that in the controls (P<0.01, analysis of covariance with age as a covariate). No significant differences were found in CD57+CD16-, CD57+CD16+ and CD57-CD16+NK cells between the low-exposure group and the controls. It is suggested that a decrease in the number of CD4+ T lymphocytes following exposure to AAs might be compensated by the increase in CD57+CD16- cells, i.e. circulating peripheral lymphocytes with poor NK cell activity.     

Decreases of CD4- and CD8-positive T lymphocytes in retired chromate workers

To investigate the effects of chromates on the human immune system, we measured total T lymphocytes and their two major subpopulations (CD4 + and CD8 + T lymphocytes) in the peripheral blood of 19 retired male workers who had been exposed to chromate at a chemical plant. The results indicated that both CD4 + and CD8 + T lymphocytes were significantly decreased, resulting in decreases in total T lymphocytes and total lymphocytes.     

Decreases of Natural Killer Cells and T-Lymphocyte Subpopulations and Increases of B Lymphocytes Following a 5-Day Occupational Exposure to Mixed Organic Solvents

The authors examined the effects of organic solvents on lymphocyte subpopulations in blood. Natural killer and T-lymphocyte subpopulations and B (CD19+) -lymphocytes were measured with flow cytometry in 16 male rotogravure printers on a Friday and on the following Monday. Numbers of all 3 subpopulations of natural killer cells (i.e., CD57+ CD16+, CD57-CD16+ and CD57+CD16- cells), 2 subpopulations of T lymphocytes (CD4+ CD45RA+ and total CD8+ cells) and total lymphocytes on Friday were significantly fewer than those found on the following Monday. Conversely, the number of B lymphocytes on Friday was significantly larger than the number on Monday. The number of B lymphocytes was significantly correlated with blood toluene levels on Friday. The alteration in the number of CD57+CD16+ NK cells from Friday to the following Monday was correlated inversely with the corresponding change in exposure level of toluene on Friday. The authors suggest that the effects of mixed organic solvents (primarily toluene) are recoverable decreases of natural killer cells and T lymphocytes and increases in B lymphocytes.     

Zinc-deficient rats have fewer recent thymic emigrant (CD90+) T lymphocytes in spleen and blood

It has been hypothesized that increased expression of the signaling protein p56(lck) disrupts maturation of T lymphocytes, leading to the lymphopenia associated with dietary zinc deficiency and malnutrition. Our objective was to examine p56(lck) protein levels, flow cytometric markers of T cell development (CD4, CD8, TCRalphabeta, TCRgammadelta and CD90) and absolute cell numbers in thymus, spleen and blood of zinc-deficient (ZD), diet-restricted (DR) and control (CTL) rats. Recent thymic emigrant (CD90+) T lymphocytes were also investigated after dietary repletion. P56(lck) protein levels were one- to twofold greater in thymocytes than splenocytes, and ZD rats had more thymocyte p56(lck) protein than CTL rats. In the thymus and blood, the proportions of T lymphocyte subpopulations (CD4-CD8-, CD4+CD8+ and CD4+CD- or CD4-CD8+) were unchanged, except for a higher percentage of TCRalphabeta+CD-CD8+ thymocytes in ZD rats. The 15-29% fewer CD90+ T cells in the blood and spleen of ZD rats were reversed after dietary repletion for 7 and 23 d, respectively. In summary, T-cell numbers were proportional to thymus and spleen weights and unaltered per unit blood volume, despite elevated thymocyte p56(lck) protein in ZD rats. In zinc deficiency, the decreased percentages of CD90+ cells in the blood and spleen could adversely affect the T-cell repertoire.     

Decreases of natural killer cells and T-lymphocyte subpopulations and increases of B lymphocytes following a 5-day occupational exposure to mixed organic solvents.

The authors examined the effects of organic solvents on lymphocyte subpopulations in blood. Natural killer and T-lymphocyte subpopulations and B (CD19+) -lymphocytes were measured with flow cytometry in 16 male rotogravure printers on a Friday and on the following Monday. Numbers of all 3 subpopulations of natural killer cells (i.e., CD57+ CD16+, CD57- CD16+, and CD57+ CD16- cells), 2 subpopulations of T lymphocytes (CD4+ CD45RA+ and total CD8+ cells), and total lymphocytes on Friday were significantly fewer than those found on the following Monday. Conversely, the number of B lymphocytes on Friday was significantly larger than the number on Monday. The number of B lymphocytes was significantly correlated with blood toluene levels on Friday. The alteration in the number of CD57+ CD16+ NK cells from Friday to the following Monday was correlated inversely with the corresponding change in exposure level of toluene on Friday. The authors suggest that the effects of mixed organic solvents (primarily toluene) are recoverable decreases of natural killer cells and T lymphocytes and increases in B lymphocytes.     

Alterations in serum cortisol, CD4+ CD8+ lymphocyte sub-population ration and T cell mediated suppression of immune responses in the malnutrition of anorexia nervosa

Serum cortisol and T lymphocyte sub-populations (CD3+, 4+ and 8+) were studied in 22 consecutively admitted patients with anorexia nervosa (AN) who had a mean weight loss of 30%. In addition Concanavalin A (Con A) mitogen induced T cell suppression of lymphocyte response to PPD (purified protein derivative of tuberculin antigen) was analysed. Increased serum cortisol concentrations were found in the AN-patients compared to the control group, with mean levels 654 and 418 nmol/l respectively. The relative numbers of CD4+ lymphocytes (mean 36.2%) and the CD4+ CD8+ ratio (mean 1.54) were significantly reduced (p < 0.05) in the AN-patients compared to the control group (mean 41.6% and 2.14 respectively). T cell mediated, Con A induced suppression of lymphocyte response to PPD was increased in AN-patients compared to the control group with low (1mug/ml) Con A concentration, but unchanged with high (5 mug/ml) Con A concentration. There was no correlation between serum cortisol concentrations and the numbers of T lymphocyte subpopulations or T cell suppressor activity. In contrast, a highly significant correlation existed between serum cortisol and the duration of AN (p < 0.002), but not with relative weight loss or anthropometric variables: triceps skin-fold (TSF) and arm muscle circumference (AMC). Immunological variables were not correlated with duration of disease. Thus, immunological alterations of the T cell system are detectable in AN, but are subtle and their clinical importance is not well known.     

病毒学抑制的HIV - 1感染者免疫衰老相关CD4+T淋巴细胞亚群的分析

目的 了解病毒学抑制的HIV - 1感染者CD4+ T淋巴细胞免疫衰老状态,探索主成分分析法能否用于评价HIV - 1患者的免疫衰老。方法 选择抗逆转录疗法治疗半年以上成年病毒学抑制HIV - 1感染者,根据CD4+T淋巴细胞计数结果分为CD4无缺陷组（≥500个/μl）和缺陷组（＜500个/μl）,每组65人,另选择22名未暴露且HIV - 1抗体检测阴性者作为对照组,采用流式细胞仪检测其CD4+T淋巴细胞（CD45RA+CD27+）、活化CD4+T淋巴细胞（HLA - DR+CD38+）和复制性衰老CD4+T淋巴细胞（CD57+CD28-）水平,运用主成分分析对三种细胞进行综合分析。结果 缺陷组（27.64%）和无缺陷组（32.04%）的初始CD4+T淋巴细胞较对照组（51.27%）有明显下降（F = 24.35,P＜0.001）,活化CD4+T淋巴细胞（14.26%,13.03%）较对照组（2.35%）有明显上升（F = 19.75,P＜0.001）;缺陷组（12.64%）的复制性衰老CD4+T淋巴细胞较无缺陷组（7.36%）和对照组（3.58%）有明显升高（F = 6.68,P = 0.002）,而无缺陷组和对照组之间无统计学差异;主成分分析能区分出三组对象CD4+T淋巴细胞免疫衰老的差异程度:缺陷组＞无缺陷组＞对照组（F = 20.787,P＜0.001）。结论 病毒学抑制良好的HIV - 1感染者即使CD4+T细胞数量正常也表现为免疫衰老,CD4+T细胞数量异常的人免疫衰老状态更严重,可运用主成分分析对病毒学抑制的HIV - 1感染者免疫衰老相关细胞进行综合分析。     

接触苯女工淋巴细胞亚群及免疫状态调查研究

Peripheral blood from 29 female subjects occupationally exposed to benzene for an average duration of 8.6 years were analysed with monoclonal antibodies (McAbs). Acid alpha-naphthyl acetate esterase (ANAE)-positive cells among lymphocytes and serum IgG, IgA and IgM levels were determined simultaneously. The results showed a decreased total number of lymphocytes, reduction of percentages and absolute numbers of both CD2+ and CD4+ cells, decreased CD8+ and CD57+ cell numbers without significant changes in their percentages, a decreased CD4+/CD8+ ratio, an increased CD20+ cell percentage without significant change in its absolute number and a decreased serum IgM level. ANAE(+)-cell percentages of lymphocytes were of marked positive correlation to CD2+ cell percentages. These results indicate that benzene can cause immunosuppressive effects to the exposed subjects and the analysis of lymphocyte subpopulations by means of McAbs may be useful for evaluating early adverse health effects on workers exposed to the toxicant.     

Flow cytometric analysis of lymphocyte subpopulations in the spleen and thymus of mice exposed to an acute immunosuppressive dose of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)

The objective of the present studies was to determine if acute exposure to an immunotoxic dose of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) produces alterations in the expression of lymphocyte surface markers as measured by multiparameter flow cytometry. The immunotoxicity of a single oral dose of TCDD was assessed by the anti-SRBC PFC response; an ED50 of 0.74 micrograms/kg was determined. Subpopulations in the spleen and thymus of C57B1/6 mice were analyzed 2 days following exposure to 2 micrograms/kg TCDD. In addition, splenic lymphocyte subsets were examined on Days 1-4 following SRBC challenge of mice treated with 0, 2, or 5 micrograms/kg TCDD. T and B cells were identified by single parameter analysis of Thy 1.2 and Ig expression. T cell subsets were defined by dual parameter analysis of CD4 and CD8 expression. In TCDD-treated mice, the percentage and the total number of double-positive CD4+ CD8+ thymocytes were significantly decreased while the percentage but not the total number of double-negative CD4- CD8- thymocytes was significantly increased. No changes in the percentage or total number of single positive (CD4+ CD8- or CD4- CD8+) thymocyte subsets were observed. In contrast to the thymus, lymphocyte subsets in the spleen were not significantly altered in percentage or total number 2 days following acute TCDD exposure. When splenic lymphocytes were analyzed daily following SRBC challenge, Ig+, Thy 1.2+, and CD4+ CD8- subpopulations remained relatively unchanged in both control and TCDD-treated animals. A small but significant decrease in the percentage of CD4- CD8+ T cells was observed on Day 3 in mice treated with 2 or 5 micrograms/kg TCDD when compared to that of vehicle-treated mice. The total number of CD4- CD8+ splenocytes was also significantly lower in the 5-micrograms/kg group on Day 3. However, this effect appeared to result from an elevation of the CD4- CD8+ subset in the controls rather than from a reduction in the TCDD-treated groups. Double-positive (CD4+ CD8+) lymphocytes were not detected in either control or TCDD-treated spleens. These results indicate that an acute dose of TCDD which reduced the splenic anti-SRBC response by 65-80% did not cause detectable changes in major splenic lymphocyte subpopulations. This is an important finding from the standpoint of utilizing lymphocyte subset analysis to screen for potential immunotoxic effects of TCDD. Specifically, the absence of subset changes does not preclude the presence of functional immunosuppression.     

Depression of thymus-dependent immunity in wasting protein-energy malnutrition does not depend on an altered ratio of helper (CD4+) to suppressor (CD8+) T cells or on a disproportionately large atrophy of the T-cell relative to the B-cell pool.

We report cell numbers within major subsets of lymphocytes in the spleen, mesenteric nodes, and recirculating pool of weanling mice subjected to protein-energy malnutrition (PEM). PEM and thymus (T)-dependent immunodepression were induced in male C57BL/6J mice by a low-protein (LP) diet fed ad libitum. Recirculating lymphocyte numbers were estimated by enumerating labeled and unlabeled cells after equilibration of a known number of fluorescein isothiocyanate-labeled C57BL/6J donor lymphocytes within well-nourished or LP recipients. Involution of the recirculating lymphocyte pool of the LP group was proportionately less than the lymphoid atrophy of the spleen and mesenteric nodes. The LP protocol exerted no influence on the ratio of helper (CD4+) to suppressor (CD8+) T cells and increased the ratio of T cells to B cells in the secondary lymphoid organs and recirculating pool. These results challenge two established concepts: that T-dependent immunodepression in PEM depends on a reduced CD4(+)-CD8+ ratio and that PEM induces greater involution within the T-cell system than within the B-cell system.     

Job insecurity and its association with health among employees in the Taiwanese general population

As employers respond to intensive global competition through the deregulation of labor, job insecurity has become a widespread problem. It has been shown to have significant health impacts in a growing number of workers, but less is known about its social distribution, the mechanisms through which it may act, and the moderating effects of gender, socioeconomic position, and company size. Utilizing data from a national survey of a representative sample of paid employees in Taiwan, we examined the prevalence of job insecurity and its associations with psychosocial work characteristics and health status. A total of 8705 men and 5986 women aged between 25 and 65 years old were studied. Information on perceived job insecurity, industrial and occupational types, psychosocial work characteristics as assessed by the Job Strain model, and various measures of health status were obtained by a self-administered questionnaire. The overall prevalence of job insecurity was high (50%). Job insecurity was more prevalent among employees with lower education attainment, in blue-collar and construction workers, those employed in smaller companies, and in older women. Insecure employees also reported lower job control, higher job demands, and poor workplace social support, as compared with those who held secure positions. Regression analyses showed that job insecurity was strongly associated with poor health, even with adjustment of age, job control, job demands, and work place social support. The deleterious effects of job insecurity appeared to be stronger in men than women, in women who held managerial or professional jobs than women in other employment grades, and in those working in larger companies than smaller ones. The findings of this study suggest that perceived job insecurity is an important source of stress, and it is accompanied with adverse psychosocial work conditions and poor health. High-risk groups were identified for further investigation.     

Immunophenotyping characteristic of the major lymphocyte populations and subpopulations in patients during salmonella infection

AIM: To study the quantitative changes in the major lymphocyte populations and subpopulations in the peripheral blood of patients during salmonellosis and find correlations of these changes with disease severity and bacterial clearance. MATERIAL AND METHODS: The study included 24 adult patients with culture-proven gastrointestinal salmonellosis. Flow-cytometry was used to identify CD19+ (B lymphocytes), CD2+ (total T lymphocytes), CD3(+)CD4+ (helper T cells), CD3(+)CD8+ (suppressor/cytotoxic T lymphocytes), CD4(+)CD29+ and CD4(+)CD45(-)RA+ (helper/ inducer subpopulation and naive Tlymphocytes) in the acute and the convalescent phases of disease. The absolute number and percentage of cells in 1 microl of peripheral blood were also determined. Immunophenotype analysis was conducted on an EPICS XL-MCL flow cytometer, Coulter, USA using monoclonal antibodies produced by the same firm. RESULTS: T and B lymphocytes and the immunocompetent T cells were slightly decreased transiently in the acute phase of the disease. Helper T lymphocytes were slightly increased with a significant increase observed of helper/inducer cells and decrease of the naive T lymphocytes. CONCLUSION: The increase of B lymphocytes at the height of salmonellosis bears additionally a diagnostic significance in determining the severity of the disease while the increase of the helper T lymphocytes can be a prognostic marker of early bacterial clearance.     

A cross-sectional study on the relationship of job stress with natural killer cell activity and natural killer cell subsets among healthy nurses

The present study investigated the effects of job stress on cellular immune function, such as NK cell activity and NK cell subsets. The participants were 61 female nurses aged 23-59, who worked in a public psychiatric hospital in Ishikawa, Japan. Each subject completed the Nursing Job Stressor Scale (NJSS) and their NK cell activity and lymphocyte surface antigens (CD16+56+) were evaluated as immune system parameters. The NJSS has seven subscales: conflict with other nursing staff, nursing role conflict, conflict with physicians or autonomy, conflict with death or dying, quantitative work load, qualitative work load and conflict with patients. Factors influencing NK cell activity, and the proportion and cell counts of CD16+56+ lymphocytes were evaluated. Increase in quantitative work load significantly decreased NK cell activity. Conversely, no linear relationship was observed between qualitative work load and immunological variables, with the highest percentage of CD16+56+ lymphocytes observed among participants in the medium work load group. The other five NJSS subscales did not relate to immune parameters. In conclusion, the results suggest that perceived job strains, particularly quantitative work load, decreased NK cell function.     

Shift schedules,work factors,and mental health among onshore and offshore workers in the Norwegian petroleum industry

The purpose of the present study was to answer the following research questions: (1) Do workers in different shift schedules differ in mental distress? (2) Do workers in different shift schedules differ in neuroticism? (3) Do shift schedules differ in psychosocial work exposures? (4) Do psychosocial work exposures contribute to mental distress among onshore- and offshore workers? (5) Does neuroticism confound the association between work exposures and mental distress? Workers on six shift-schedules answered a questionnaire (1,471 of 2,628 employees). Psychological and social work factors were measured by QPS_Nordic, mental distress was measured by HADS and neuroticism was measured by EPQ. The results showed 1) No differences in mental distress between workers in different shift schedules, 2) Revolving-shift workers reported higher neuroticism compared to day workers, 3) Swing-shift workers and revolving-shift workers reported lower job control compared to permanent-night and -day workers, 4) Job demands and role conflict were associated with more mental distress. Job control, role clarity, support, and leadership were associated with lower mental distress, 5) Neuroticism influenced the relationship between psychosocial work factors and mental distress. The present study did not find differences in mental distress between shift schedules. Job characteristics may be contributing factors when determining health effects of shift work.