Carcinoma of the alimentary canal — A statistical study based on autopsy data from 1928 to 1972

Summary An analysis of autopsy data shows that during the period 1928–1972 the relative frequency of carcinoma of the stomach has remained practically unchanged. A similar trend is apparant from the mortality statistics for Vienna from 1955 to 1972. Whereas for the lower and middle age groups there is a real decrease during the period 1928–1952, an opposite trend is visible for the highest age group. The stomach and the lower parts of the large intestine are the most frequent sites of carcinoma of the alimentary canal. The frequency distribution is explained on the basis of the contact hypothesis.     

Prevention of work‐related airway allergies; summary of the advice from the Health Council of the Netherlands

The Health Council of the Netherlands published a report in which the best procedure and method for recommending health‐based occupational exposure limits (OELs) for inhaled allergens were identified by evaluating the scientific state of the art. Many respiratory disorders in the workplace arise from inhalation of substances which can cause allergy. To protect workers against respiratory allergy, various preventive measures are taken, one of them being reduction of exposure by setting legally binding standards. These are based on health‐based OELs that specify a level of exposure to an airborne substance, a threshold level, below which it may reasonably be expected that there is no risk of adverse health effects. The Council is of the opinion that an OEL should prevent against allergic sensitization, as sensitization plays a crucial biological role and is a prerequisite for the development of allergy. Furthermore, the Council considers it most likely that the exposure level below which no allergic sensitization develops for most allergens is so low, that OELs are difficult to set with the current knowledge and technical feasibilities. An alternative approach is to accept exposure, which carries a small predefined risk in developing allergic sensitization. In addition, it is worth considering periodic screening of exposed workers on allergic sensitization, because timely intervention can prevent worse. The feasibility of periodic screening and what else is needed to comply with the most important criteria, should however be judged case‐by‐case.     

Sensitization to sunflower pollen and lung functions in sunflower processing workers

BACKGROUND: This study aimed to investigate whether exposure to sunflower pollen (Helianthus annuus) increases both sensitization and respiratory symptoms, and whether or not it affects lung functions in sunflower processing workers. METHODS: The largest sunflower processing factories in the Thrace region of Turkey participated in this study. Workers from the units directly exposed to sunflower seed enrolled as the study group (n = 102) and workers who were not directly exposed to Helianthus annuus pollen (n = 102) were the control group. Detailed questionnaires covering respiratory and allergic symptoms were completed, and skin prick tests and lung function tests were performed. RESULTS: We found a very high rate (23.5%) of sensitization to Helianthus annuus in the study group compared to the controls (P<0.001). Logistic regression analysis showed that the risk of sensitization to H. annuus was increased 4.7-fold (odds ratio = 4.17, 95%) confidence interval = 1.3-16.7) if subjects were exposed to sunflower pollen in the workplace. While asthmatic symptoms and allergic skin diseases were not different between the two groups, workers in the study group had a higher rate of allergic rhinitis and conjunctivitis (P<0.05). We found that pulmonary function was significantly impaired in the study group (P<0.01). Using a multivariate analysis model, inclusion in the study group was found to be a predictive factor for impairment of lung function (P=0.002). CONCLUSIONS: We conclude that sunflower pollen has high allergenic potential, especially when there is close contact, and exposure to sunflower pollen in the workplace can result in impairment in lung function.     

High levels of Lp(a) lipoprotein in a family ith cases of severe pre-eclampsia

We report a family with two cases of severe pre-eclampsia/eclampsia in which very high levels of Lp(a) lipoprotein were found. The serum level of Lp(a) lipoprotein is genetically determined and the Lp(a) apolipoprotein has a close homology to plasminogen. Very high levels of Lp(a) lipoprotein might interfere with the fibrinolytic/thrombolytic process in man. A previous report suggested that a high maternal serum Lp(a) lipoprotein level can cause fetal growth retardation, and it is proposed that very high levels might lead to increased deposition of fibrin in the uterine spiral arteries in pregnancy, which is central in the pathogenesis of pre-eclampsia. If confirmed, a very high Lp(a) lipoprotein level could be one risk factor for pre-eclampsia that is genetically determined.     

Inhibitory effect of plasma obtained from hypophysectomized and control women on the assay of bioactive luteinizing hormone

The purpose of this study was to determine the effect of components of female plasma on the value of bioactive luteinizing hormone (LH), especially in the presence of low immunological LH value. Using both an immunoradiometric assay (IRMA) and rat Leydig cell bioassay, immunoreactive (I) and bioactive (B) LH were assessed in plasma collected from women during a gonadotrophin releasing hormone (GnRH) test performed on day 7 of a spontaneous cycle. Two modes of response to an acute administration of GnRH were defined: normal production of gonadotrophins (group I) and excessive secretion (group II) associated with a significant difference in the B/I-LH ratio between the two groups. The B/I-LH ratio did not vary with sampling time during the test in either group. The addition of LH-free plasma collected from hypophysectomized women caused a 30% decrease in testosterone production compared to control values (in the presence or absence of hLH standard). A partial restoration of testosterone production was observed if plasma was first treated with PEG 12%. The inhibitory factor(s) was also present in plasma from ovulatory women, even after treatment by an antibody against the entire LH molecule. The effect of normal (A) or low I-LH plasma (B) on testosterone production varied strongly according to the plasma volume added to the bioassay, as well as to plasma treatments. Diethylether treatment caused a 50% decrease in testosterone secretion for plasma B (but not for A) whereas a diminution of the steroidogenesis is observed after a PEG treatment of plasma A (but not for B), suggesting that different inhibitory factors are present in plasmas A and B. Therefore the LH bioactivity measured in the rat Leydig cell assay, in terms of testosterone output, seems to represent a balance between the LH molecule and the presence of inhibitory factors in the plasma.     

Disturbances of Haemostasis in Diabetes Mellitus

Diabetes mellitus is associated with disturbances in haemostasis that could contribute to the development of thrombotic complications.The present study was undertaken to determine the behavior of coagulation variables and fibrinolytic system in diabetes mellitus. Forty five diabetic patients and forty five matched controls were evaluated by doing the following haemostatic parameter, prothrombin time, partial thromboplastin time, thrombin time, coagulation factors assay II, VII, IX, & plasma fibrinogen, ADP-induced platelet aggregation, protein C, a₂- antiplasmin, PAI and FDPs. Generally diabetic patients have high levels of fibrinogen, a₂- antiplasmin, & PAI and lower level of protein C. Other haemostatic parameters did not show statistically significant difference between diabetic patients and control group. Significantally elevated levels of PAI, a₂- antiplasmin together with low protein C level in diabetic patients may result in the disturbance of haemostatic balance favoring thrombotic events. Conclusion: High levels of plasma fibrinogen, a₂A- antiplasmin with low plasma protein C activity could lead to a prothrombotic tendency in insulin dependent diabetic patients. Moreover, in non-insulin dependent diabetic patients, the above mentioned parameters together with high levels of ADP-induced platelet aggregation and plasminogen activator inhibitor may increase the risk of thrombotic complications. Obesity can be considered as an additional risk factor for development of thrombosis in diabetic patients.     

Sensitization and lung function in workers occupationally exposed to natural thickening products

BACKGROUND: Three workers engaged in the manufacture of natural thickener products (Cassia spp., guar, and tamarind flour) were occupationally sensitized to Cassia spp. Therefore, a cross-sectional study on the prevalence of sensitization among and respiratory health of the employees of this plant was conducted. METHODS AND RESULTS: Sixty-two workers (36 with high, 26 with low exposure) participated in the survey. Skin prick tests and specific IgE tests with extracts of these components revealed that 11.3% were sensitized to Cassia spp. and 9.7% to at least one species of storage mites, with a significantly higher portion of atopic subjects in the sensitized group. Overall, 55% of the subjects reported work-related symptoms (upper and lower airways, eyes, or skin). FVC % pred. was significantly lower in highly exposed workers, while RV % pred. and RV%TLC % pred. were significantly higher in this group. In the multivariate model, sensitization was not a risk factor for impairment of lung function. CONCLUSIONS: Dust exposure to flours may not only cause allergic sensitization but also induce chronic changes in lung function.     

Altered production of tumour necrosis factors alpha and beta and interferon gamma by HIV-infected individuals.

In vitro studies shows that recombinant tumour necrosis factor (TNF) alpha and beta, and interferon-gamma (IFN-gamma) can enhance HIV replication, and peripheral blood mononuclear cells (PBMC) infected with HIV in vitro secrete high levels of the same cytokines. As T cells secrete all three mediators, the capacity of T cell activation signals to trigger cytokine production in PBMC from HIV-infected individuals was investigated as such patients may be immunocompromised. We demonstrate that asymptomatic seropositives in CDC group II/III as well as patients who have progressed to CDC group IV of the disease proliferate efficiently to anti-CD3 antibody, recombinant interleukin-2 (rIL-2), phytohaemagglutinin (PHA), PHA plus phorbol 12,13 dibutyrate (PMA) but secrete significantly (P less than 0.05) higher amounts of TNF-alpha, TNF-beta and IFN-gamma compared with controls in response to the same stimulants. We also show a difference between group II/III and group IV patients with the latter secreting more TNF-alpha and IFN-gamma. The kinetics of TNF-alpha and -beta, and IFN-gamma production was stimulus dependent with overall levels varying in time for each stimulus. Furthermore, the kinetics of the response to all three stimulants were altered in seropositives; CDC group II/III and group IV patients secreted higher levels of cytokines over several time points compared to controls. The altered production of these mediators by HIV-infected patients may contribute to disease progression and to the pathogenesis of AIDS.     

Electrodermal Lability and Visual Information Processing

Individual differences in electrodermal lability have been related to performance in vigilance and reaction time tasks. The goal of the present study was to employ an "additive factors" approach to identify the stages of information processing that might underlie these effects. Nineteen labile and 17 stabile subjects performed a choice reaction time task in which a visual imperative stimulus was presented under two conditions of intensity (presumed to affect the speed of pre-processing operations) X three conditions of degradation (which influences later encoding processes related to feature extraction). Measures of both reaction time and movement time were obtained. The major findings were: (a) labile subjects had faster reaction times than stabiles, and (b) lability interacted significantly with stimulus degradation. Labiles also tended (p less than .10) to have faster movement times. This pattern indicates that labiles and stabiles differ in the performance of later encoding operations, and possibly in the speed of motor processes as well. However, they do not appear to differ in the early pre-processing of the simple physical attributes of a stimulus.     

Single-strand breaks, chromosome aberrations, sister-chromatid exchanges, and micronuclei in blood lymphocytes of workers exposed to styrene during the production of reinforced plastics

Chromosome aberrations (CA), micronuclei (MN, cytokinesis-block [CB] method), and sister-chromatid exchanges (SCE) were analysed in blood lymphocytes of 17 workers and 17 control subjects. The mean urinary mandelic acid level (average 9.4 mmol/l) and styrene glycol in blood (average 2.5 mumol/l) implied exposure to about 300 mg/m3 of styrene in the plant. The number of CA was significantly higher in non-smoking workers compared with nonsmoking controls. A significant correlation was observed between duration of exposure and individual CA level of all workers. No significant effects were observed in MN or SCE. Single-strand breaks (SSB) in DNA of isolated lymphocytes were studied in nine of the workers and eight of the controls by the DNA-unwinding technique. The results showed an increase in SSB among the exposed workers. The present findings support earlier reports on the increase of structural CA in blood lymphocytes of workers in the reinforced plastic industry, and also show that SSBs are elevated in such workers.