Determination of forced expiratory volume (FEV 1) and maximal peak expiratory flow within the scope of routine diagnosis in general practice

In 5 Viennese general practice offices we investigated patients by spirometry with the following indications: differential diagnosis of dyspnea; every 3rd smoker of more than 10 cigarettes a day (including asymptomatic ones); cough and nasal disorders of more than 4 weeks duration; indicative physical findings (cyanosis or auscultation). The sample control group was matched for age and gender and did not have any symptoms characteristic of the indication group. Nevertheless a spirometric test was also carried out in these patients. A total of 212 patients were examined in 4673 consultations on 202 workdays in the 5 offices. In the group of 109 patients 62 (56.9%) had dyspnea and/or positive signs on auscultation. Of these 62 patients 39 (62.9%) had 1 or more positive findings either from PEF or FEV 1 or both. There were significantly more referrals for X-rays in case of abnormal lung function. The control group of 103 obviously healthy persons in particular showed a significantly higher number of abnormal PEF values than expected (31 persons, 30.1%).     

The birth and development of the forced expiratory manoeuvre: a tribute to Robert Tiffeneau (1910-1961)

The forced expiratory manoeuvre was first described by Tiffeneau and Pinelli working in Paris (France), in December 1947, who proposed measurement of the "pulmonary capacity usable on exercise" (capacité pulmonaire utilisable à l'effort) (CPUE), the maximal volume expelled in one second after a deep inspiration. It was intended to replace the measurement of the maximum breathing capacity, a difficult and tiring manoeuvre. A similar approach was later followed in the USA by Gaensler, who proposed the "timed vital capacity" in 1951. The name CPUE was changed to "volume expiratoire maximum seconde" (VEMS) by a group of European experts, who met in Paris on February 13, 1954, whereas the expression "forced expiratory volume" was adopted by the British Thoracic Society in 1957. Despite numerous attempts to examine the forced expiration in a different manner, the VEMS and/or forced expiratory volume in one second (FEV1) remain, after 50 yrs the main variables used daily by the respiratory physician. Although primarily a pharmacologist, Robert Tiffeneau (1910-1961) undoubtedly deserves to figure among the pioneers of respiratory medicine.     

综掘工作面粉尘运移的数值模拟及压风分流降尘方式研究

针对综掘工作面产生尘量高,煤尘浓度大,降尘效率低的现状,结合流体力学、气固两相流理论和射流理论等相关理论,采用FLUENT模拟技术,研究\     

The interactive effect of chronic exposure to noise and job complexity on changes in blood pressure and job satisfaction: A longitudinal study of industrial employees.

The hypothesis of this study was that noise exposure level and job complexity interact to affect changes in blood pressure (BP) levels and job satisfaction over 2–4 yrs of follow-up. Results showed that among workers exposed to high noise, those with complex jobs showed increases in BP that were more than double shown by those with simple jobs. Under low noise exposure, there was a small increase in BP for workers with complex jobs but about a 3-fold increase in workers with simple jobs. The prevalence of elevated BP showed a similar trend. Job satisfaction increased among workers with complex jobs but was much less in those exposed to high noise. It was concluded that exposure to occupational noise has a greater negative impact on changes in BP and job satisfaction over time among those performing complex jobs. In contrast, job complexity had a clear beneficial effect for workers exposed to low noise. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The value of forced expiratory volume in 1 s in screening subjects with stable COPD for PaO2 < 7.3 kPa qualifying for long-term oxygen therapy

Guidelines on the management of chronic obstructive pulmonary disease (COPD) issued by the European Respiratory Society (ERS), British Thoracic Society (BTS), American Thoracic Society (ATS), and Department of Health for England and Wales (DoH) suggest differing values of forced expiratory volume in 1 s (FEV1) below which arterial blood gas analysis should be performed to determine the presence of severe hypoxaemia and possible long-term oxygen therapy (LTOT) requirement. This study aimed to determine the value of FEV1 at these different levels in screening for LTOT requirement defined as PaO2 < 7.3 kPa in subjects with stable COPD. Comparative measures were taken against other lung function tests of volume and diffusing capacity. A retrospective analysis of paired lung function and arterial oxygen measurements in 491 subjects was made. The positive and negative predictive values, sensitivity and specificity of FEV1 < 70% predicted (ERS), FEV1 < 50% predicted (ATS), FEV1 < 40% predicted (BTS) and FEV1 < 1.51 (DoH) were determined for fulfilling LTOT criteria (PaO2 < 7.3 kPa). The correlation between lung function variables and PaO2 was established. Logistic regression analysis was used to classify subjects with PaO2 < 7.3 kPa and PaO2 > or = 7.3 kPa. Using FEV1 to screen for LTOT requirement produced a high negative predictive value at all four suggested limits (FEV1 < 70% 100%, FEV1 < 50% 96%, FEV1 < 40% 95%, FEV1 < 1.51 97%). However, the positive predictive values were low (FEV1 < 70% 13%, FEV1 < 50% 16%, FEV1 < 40% 19%, FEV1 < 1.51 15%) as were sensitivities. No single lung function variable was a strong determinant of PaO2. FEV1 % pred (r = 0.40), FVC % pred (r = 0.34) and TLCO % pred (r = 0.27) had the strongest relationships. Logistic regression also placed FEV1 % pred and TLCO % pred as the best predictors of PaO2 < 7.3 kPa. We conclude no lung function variable correlates well with PaO2 in subjects with stable COPD. The best predictor of PaO2 < 7.3 kPa was FEV1 % pred. Whilst a low FEV1 is a poor predictor of LTOT requirement in an individual, PaO2 < 7.3 kPa is only found in subjects with a low FEV1. A high FEV1 may be used to exclude subjects from further investigation for LTOT and prevent unnecessary arterial sampling.     

The effect of repeated exposure to forced swimming on extracellular levels of 5-hydroxytryptamine in the rat

The present study examined the effects of electrolytic lesions of the Medial Septum/Vertical Diagonal Band of Broca (MS/VDBB), the Globus Pallidus (GP) and the Substantia- Innominata/Ventral Pallidum (SI/VP) on the performance of rats in object-recognition memory and radial-maze learning tests. In the latter test, subgroups of sham-operated, MS/VDBB, SI/VP and GP rats were treated with saline, amphetamine or physostigmine. (1) In the object recognition task, the level of discrimination wa s significantly lower in GP compared to SI/VP and in both GP and SI/VP compared to Control and MS/VDBB groups, however, only GP did not discriminate between new and familiar objects; (2) in the radial-maze task, GP and SI/VP lesions produced weak and tran sient impairment whereas MS/VDBB lesions produced a large deficit; (3) in the radial-maze task, performance of normal rats was improved with physostigmine and impaired with amphetamine. The effect of amphetamine was significant on non-memory measures only; (4) neither amphetamine nor physostigmine improved memory performances of lesioned rats. These results suggest that the septo-hippocampal projections are involved in spatial memory but not in object recognition whereas the integrity of Substantia Inno minata/Ventral Pallidum does not seem critical for either task. The cholinergic nature of the deficit produced by the medial septal lesion remains in question because of improvements seen in sham-operated rats but not in lesioned rats.     

The effect of prostatilen on the hemostatic indices in chronic prostatitis (a clinical and experimental study)

Continuous monitoring of dynamic changes of transcranial regional cerebral oxygenation (rSO2) was performed in 7 healthy volunteers (mean age 40.9 +/- 12.6 years; range 25-62 years) during normo- and hyperbaric oxygenation (HBO at 2.5 and at 1.95 ATA) using an INVOS 3100 cerebral oximeter. A significant change between HBO and control phase could be found in rSO2, alterations (p < 0.05; ANOVA, Tukey test). The results suggest that the calculation of rSO2 may be a useful method to monitor changes of oxygen saturation under hyperbaric conditions. However, the absolute quantification of rSO2 is useless at the moment and needs further investigation.     

Evaluation of the effect of environmental exposure to tobacco smoke on variability of peak expiratory flow rate in children

A panel study was conducted in autumn (116 children) and repeated in spring (66 children) to test the hypothesis that the individual variability of peak expiratory flow rate (PEFR) depends on the environmental exposure to tobacco smoke (ETS). PEFR was measured twice a day (morning: PEFR-M; evening: PEFR-E), using individual meters at homes, in children exposed (ETS+) and not exposed (ETS-) to tobacco smoke at home. In examined groups the individual variability of PEFR-M was--on average--8.0% (ETS+; autumn), 8.1% (ETS+; spring), 10.5% (ETS-; autumn) and 7.7% (ETS-; spring). The individual variability of PEFR-E was 8.0% (ETS+; autumn), 7.9% (ETS+; spring), 9.5% (ETS-; autumn) and 7.4% (ETS-; spring). The results of multivariate analysis of within- and between-subject variability showed the presence of statistically significant within-subject variability only in ETS+ group (PEFR-M in autumn; PEFR-M and PEFR-E in spring). With all the limitations of a panel study design the findings suggest that environmental exposure to tobacco smoke in children affects the degree of within-subject variability of PEFR in children.     

Evaluation of chronic respiratory effects in the potato processing industry: indications of a healthy worker effect?

OBJECTIVE: To investigate the occurrence of chronic respiratory effects of exposure to organic dust in the potato processing industry. METHODS: Self reported chronic respiratory symptoms and spirometric lung function were assessed in a cross sectional study among 135 potato processing workers. A comprehensive study of current exposure to dust, endotoxin, and potato antigens had been performed previously. Workers were grouped into low and high exposure categories for each of the three exposure indices. Relations between exposure concentrations and respiratory health variables were investigated either by calculating prevalence rate ratios or by performing linear regression analyses. Atopy was assessed by measuring total immunoglobulin E (IgE) and specific IgE to five common aeroallergens in serum samples of workers. RESULTS: Evident relations between current exposure indices and respiratory health in the entire group were not found. Workers employed < or = 5 years showed a two-fold higher prevalence of respiratory symptoms, lower lung function, and higher endotoxin exposure than workers employed for > 5 years. Also, atopy was more prevalent in workers employed < or = 5 years. After stratification for duration of employment, negative effects of endotoxin on lung function among workers employed < or = 5 years were suggested. CONCLUSIONS: This study does not show chronic respiratory effects of exposure to organic dust in the potato processing industry, despite the fact that the levels of exposure to endotoxin found in this industry have been reported to be associated with decreases in lung function in other occupational settings. A likely explanation for not detecting apparent effects might be that many symptomatic workers drop out of this industry a few years after starting the job, suggesting a healthy worker effect.     

Electron microscopic microanalysis of bronchoalveolar lavage: a way to identify exposure to silica and silicate dust

OBJECTIVES: The diagnostic implications of finding non-fibrous inorganic particles in bronchoalveolar lavage (BAL) fluid has not been fully assessed. The aim of this study has been to measure the silica and non-fibrous silicates in BAL fluid from populations with different exposures to inorganic dust, and to find whether such measurement is useful for diagnostic purposes. MATERIALS AND METHODS: BAL samples from 19 subjects with only environmental exposure to inorganic dust (group A, mean (SD) age 50.7 (15.2)), 23 subjects with normal chest x ray films exposed to silica or silicates at work (group B, mean (SD) age 52.0 (12.4)), and 15 subjects with a previous diagnosis of silicosis (group C, mean (SD) age 68.0 (6.5)) were studied. Absolute and relative cell counts were found, and the samples were prepared for microanalysis by electron microscopy (EM). Firstly, semiquantitative x ray microanalysis was performed to find the level of silicon (Si) (peak/background Si) and this was followed by microanalysis of individual particles by EM. Variables related to the level of Si detected were assessed with multivariate analysis. RESULTS: Detected levels were higher in group B (2.09, 95% confidence interval (95% CI) 1.56 to 2.82) and C (1.50, 95% CI 1.07 to 2.12) than in group A (0.87, 95% CI 0.66 to 1.16) (P < 0.05, Dunett t test). A first multivariate analysis showed that exposure to silica or silicates was the only determinant of the level of Si expressed as log peak/background Si, when adjusted for age, sex, smoking habit, and cell count. A second multivariate analysis with microanalysis of individual particles as an independent variable showed the silica count to be the main predictor of detected concentration of Si. Silica and non-aluminium silicates together explain 55.5% (R2) of the variation in detected levels of Si. CONCLUSIONS: Detected levels of Si in BAL fluid depend on silica count and are higher in subjects with exposure to inorganic dust at work, but will not discriminate between exposed subjects with and without silicosis. Because semiquantitative x ray microanalysis does not accurately define exposure to non-silica inorganic particles, this measurement must be followed by EM microanalysis of individual particles in most cases, especially when exposure to silicates or metal dust is suspected.     

Use of a semi-continuous culture system (RUSITEC) to study the effect of pH on microbial metabolism of thiamin (Vitamin B1)

After a bout of intense exercise, especially in untrained persons recovery of muscle force is often slow. Force depression is much more marked at low frequencies of stimulation than at high frequencies ("low-frequency fatigue') and recovery can take more than 1 day. Delayed force recovery is also seen in single muscle fibres from frog and mouse after fatigue induced by repeated, brief contractions. Evidence from our own and other laboratories indicates that the impairment is unlikely to result from metabolic changes and points to a defect in excitation-contraction coupling. We demonstrate that the likely site of failure is in the coupling between t-tubule depolarization and release of Ca2+ from the SR. The causative agent appears to be a localized increase in cytoplasmic Ca2+ which initiates some disruptive process, which can, however, be fully reversed, albeit slowly. Our experimental evidence does not support the involvement of Ca(2+)-activated proteases. Attempts to clarify the possible role of Ca(2+)-activated lipases (phospholipase A2) and Ca2+/calmodulin have been hampered by side-effects of available inhibitors. Efforts to clarify how Ca2+ exerts its effects are continuing.     

The effect of "standardized forced diuresis" (SFD) on serum and urinary electrolytes(author's transl)

The effect of standardized forced diuresis (SFD) on the serum and urinary electrolyte levels was investigated in 10 cases of severe self-poisoning with hypnotic drugs. Diuresis was initiated by furosemide and maintained at an hourly urinary ouput of 2 litres. Fluid and electrolyte substitution was carried out with a standardized electrolyte solution. Initiation and termination of the SFD was performed abruptly. The mean values of sodium, potassium, chloride and phosphorus in the urine varied widely at the beginning of the SFD, while the calcium and magnesium values varied only slightly. During SFD, urinary stabilization occured at a particular ionogram, in correlation to the electrolyte concentrations in the infusion fluid and with only minimal individual variation. Owing to this satisfactory correlation, none of the patients developed signs of electrolyte disturbances, so that no correction of the infusion constitution was necessary. The abrupt termination of the SFD prevented electrolyte disturbances in the recovery phase.     

Ambient, biological, and biological effect monitoring of exposure to polycyclic aromatic hydrocarbons (PAHs)

A novel strategy was utilised to assess the risk to health from exposure to polycyclic aromatic hydrocarbons (PAHs). Ambient monitoring was carried out by personal sampling. Urinary thioethers (UTh) and urinary 1-hydroxypyrene (1-HP) were utilised for biological monitoring. Urinary d-glucaric acid (UDGA) and sister chromatid exchange (SCE) in peripheral blood lymphocytes were used as biological effect markers. The population was categorised into exposed and control groups according to the external dose of PAHs. The excretion of 1-HP in the controls over the 3-day period showed a relatively stable baseline, while the exposed showed a significant increase over the same period of time. SCE frequency in the exposed population was significantly different from controls.     

Accumulation of cadmium in and its effect on bank vole tissues after chronic exposure

Primary adrenal lymphoma (PAL) is extremely uncommon. We describe a case of clinically silent non-Hodgkin's B-cell lymphoma of diffuse large cell type with exclusive left adrenal localization. The tumor was discovered by computed tomography (CT) as a 2.5-cm dense mass and diagnosed at autopsy. Literature concerning this unusual neoplasm is reviewed. During the early stage, particularly when the lesion is small, PAL is likely to be missed. This unusual entity should be included in the differential diagnosis of adrenal masses so that early diagnosis may be made and intervention might dramatically affect the clinical outcome.     

Movie exposure to alcohol cues and adolescent alcohol problems: A longitudinal analysis in a national sample.

The authors tested a theoretical model of how exposure to alcohol cues in movies predicts level of alcohol use (ever use plus ever and recent binge drinking) and alcohol-related problems. A national sample of younger adolescents was interviewed by telephone with 4 repeated assessments spaced at 8-month intervals. A structural equation modeling analysis performed for ever-drinkers at Time 3 (N = 961) indicated that, controlling for a number of covariates, movie alcohol exposure at Time 1 was related to increases in peer alcohol use and adolescent alcohol use at Time 2. Movie exposure had indirect effects to alcohol use and problems at Times 3 and 4 through these pathways, with direct effects to problems from Time 1 rebelliousness and Time 2 movie exposure also found. Prospective risk-promoting effects were also found for alcohol expectancies, peer alcohol use, and availability of alcohol in the home; protective effects were found for mother's responsiveness and for adolescent's school performance and self-control. Theoretical and practical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Immunosuppression in adult female B6C3F1 mice by chronic exposure to ethanol in a liquid diet

The overall objective of these studies was to characterize the effects of ethanol on the immunocompetence of adult female B6C3F1 mice. To obtain a significant suppression in the antibody response to SRBC, splenocytes from untreated mice had to be directly exposed to concentrations of ethanol from 0.3% to 3.0%, or to acetaldehyde at concentrations greater than 0.03%. We do not believe that these results are consistent with a role by a direct effect by either ethanol or its primary metabolite because these concentrations are higher than what could be obtained as reasonable blood levels. For in vivo exposure, we employed a pair-feeding regimen which was based on a liquid diet containing 5% ethanol (v/v) that provided 36% of the caloric intake as ethanol. Our results indicated that there was a definite temporal relationship to the consequent suppression of the antibody response to SRBC in that no effect was observed after 14 days exposure, and that the magnitude of the suppression increased from 18% after 21 days to 70% after 42 days. We also monitored the liver for histopathology and observed that the ethanol-induced liver damage was restricted to steatosis (fatty liver), which was also manifested with time and which was most pronounced after 42 days exposure. In contrast to our results with the in vivo antibody response, we saw no effect on mitogen-induced proliferation by splenocytes from ethanol-treated mice. These results prompted us to measure in vitro antibody responses by splenocytes from ethanol-treated mice. We saw no suppression of the in vitro antibody responses to SRBC, DNP-Ficoll or LPS after any length of exposure to ethanol, and speculated that the basis for the suppression of the in vivo antibody response was an indirect consequence of exposure. We subsequently determined that when normal splenocytes were cultured in 5% serum from ethanol-exposed mice (42-day group), there was a > 80% suppression relative to the serum from the pair-fed controls. As important controls for these studies, we have demonstrated that there was no difference between the responses of normal lymphocytes cultured in 5% normal mouse serum and in 5% serum taken from the pair-fed restricted controls. A determination of the ethanol content in the serum from ethanol-exposed mice (42-day group) indicated that the amount of ethanol present in these cultures was < 0.003%.(ABSTRACT TRUNCATED AT 400 WORDS)