The characteristics of gastroduodenal pathology in the workers of a plant for plastic construction materials

Out of 162 workers exposed to chemicals in the manufacture of construction plastics an outpatient and inpatient examination revealed gastrointestinal problems in 84.3%, vegetative nervous disorders in 62.6% of the examinees. In a random sample of 47 workers high acid production occurred in 63.3% and erosions, ulcers, cicatrices in the stomach and duodenum in 45.2% of them. No HLA genetic predisposition to duodenal ulcer was reported. Histological findings on gastroduodenal mucosa biopsies were indicative of the dystrophy in the chief and lining cells of the gastric glands, epithelium and stroma with formation of the dark cells. The authors insist on consideration of the above facts in examination and treatment of workers exposed to chemicals at construction plastics plants.     

Lymphocyte subpopulations in the mammary gland of the goat

Mammary glands of pregnant, lactating and resting goats were studied by immunohistochemistry for lymphocyte subpopulations using a panel of monoclonal antibodies. All T lymphocyte subpopulations that may have a role in the immune response, CD2+, CD4+, CD8+ and gamma delta T cells and subsets, were present in the mammary gland and were noted to increase in number progressively during pregnancy, decrease significantly during lactation, and then moderately increase during the resting period. CD4+ cells, the predominant cell type in the mammary gland, were located mainly in the connective tissue, whereas CD2+, CD8+ and TcR1-N24+ cells were predominant in the intraepithelial areas. TcR1-N6+ cells were detected almost exclusively during pregnancy, being localized mainly in the connective tissue. Their proportion decreased markedly following parturition. Very few WC1-N3+ and -N4+ cells were detected in the mammary gland. It is suggested that the majority of gamma delta T lymphocytes in the mammary gland of the goat are CD2+ CD8+ WCl-, a distinctive subset from that of the WCl+ subset in peripheral blood.     

Lymphocyte activation gene-3 (LAG-3) expression and IFN-gamma production are variably coregulated in different human T lymphocyte subpopulations

We evaluated the relationship between cytokine profile and the expression of the lymphocyte activation gene-3 (LAG-3) in both T cell clones and polyclonal T cell lines; LAG-3 is a CD4-like protein whose expression is reportedly restricted to Th1/0 cells and dependent upon IFN-gamma. We found that, while LAG-3 was expressed only by CD4+ T cell clones producing IFN-gamma, most CD8+ clones producing IL-4 but not IFN-gamma (i.e., with a T cytotoxic-2-like profile) were LAG-3+. The intensity of LAG-3 expression by CD8+ clones correlated with the amount of released IFN-gamma, suggesting that this cytokine is not required for expression but rather for the up-regulation of LAG-3. Flow cytometric analyses of polyclonal T cell lines confirmed that LAG-3 could be expressed by both CD4+ and CD8+ cells that did not contain cytoplasmic IFN-gamma. In these cell lines, large proportions of CD4+ and CD8+ cells coexpressed LAG-3 and CD30, a putative marker of Th2-like cells. Overall, our data do not support the earlier suggestion that LAG-3 and CD30 are selective markers of T cells with type-1 and type-2 cytokine profiles, respectively.     

Nervous system diseases in workers of a large metallurgic plant

Epidemiological investigations were carried out in an industrial plant in a population of about 16 000 people. The overall morbidity was 1 241.8 cases of nervous system diseases per 100 000 of population and the annual prevalence of neurological diseases was 473.7 per 100 000. The most frequent disease was sciatic pain, followed in order of frequency by epilepsy, vasomotor headaches, subjective symptoms after craniocerebral trauma, Parkinson's disease, clinically evident cerebral atherosclerosis and disseminated sclerosis. No significant effect of the type of occupation on the development of nervous system diseases was observed.     

Zoonoses transmitted by ticks in forest workers (tick-borne encephalitis and Lyme borreliosis): preliminary results

In order to investigate the diffusion of infections transmitted by ticks (TBE and Lyme borreliosis) in forest workers, a serological investigation was carried out in the Province of Trento (Northern Italy) on the sera of 465 subjects at potential risk (foresters, hunters, woodcutters, gamekeepers). Antibodies for TBE virus were found in 5 subjects (1.07%) working in the same area, and antibodies for Borrelia burgdorferi were found in 15 subjects (3%). All three clinical cases of TBE identified in the Province of Trento reported that they had been bitten by ticks in the same geographical area. The presence of specific antibodies for TBE virus was tested on the sera of animals grazing in several areas: 4 positive cases were observed in the same area as the human cases reported above.     

Effect of plastic working on the structural stability of composite (nickel-chromium alloy)-tungsten materials

Conclusions The character of diffusional interaction of the components of tungsten-reinforced heat-resisting sheet composite materials produced by hot forging with subsequent plastic working depends on the latter's degree of plastic deformation. The loss of chromium from the surface of such a CM varies depending on the degree of plastic deformation and on the composition of the matrix alloy. Tungsten fibers stabilize the composition of a CM by acting as obstacles in the paths of chromium diffusion fluxes.Translated from Poroshkovaya Metallurgiya, No. 3(255), pp. 40–44, March, 1984.     

Lymphocyte phenotyping in infants: maturation of lymphocyte subpopulations and the effects of HIV infection

Oxygen administration is one of the most important therapeutic interventions for a child with severe acute lower respiratory tract infection (ALRI). Inexpensive and efficient methods of oxygen administration are highly desirable in hospitals in developing countries. The objectives of this study were to compare the frequency and nature of complications when nasopharyngeal catheters or nasal prongs are used to deliver oxygen. One hundred and twenty-one children between the ages of 2 weeks and 5 years with hypoxia due to ALRI were randomized to receive oxygen via a catheter (61 children) or via nasal prongs (60 children). The two groups were similar in terms of diagnoses, clinical severity, oxygen saturation on admission and case fatality rates. There was no difference in the incidence of hypoxaemic episodes between the two groups. The oxygen flow rates required on the day of admission for adequate oxygenation (SaO2 > 90%) ranged from 0.8 litres per minute to 1.2 litres per minute. The required oxygen flow rate decreased during the course of treatment. Mucus production was more of a problem in the catheter group, and nasal blockage, intolerance of the method of oxygen administration and nursing effort were generally higher amongst the catheter group, but none of these differences was significant. Ulceration or bleeding of the nose was significantly more common in the catheter group (19.7% vs 6.7%, p < 0.05). Abdominal distension and nasal perforation were not seen in either group. This study suggests that nasal prongs are safer, more comfortable and require less nursing expertise than nasopharyngeal catheters for administration of oxygen to children.     

An in vivo study of a clinical surfactant used with poly(vinyl siloxane) impression materials

The aim of this study was to determine whether the use of a topical surfactant (Hydrosystem), designed for clinical use, improved the quality of the impression surface of two poly(vinyl siloxane) materials used in vivo. Before impressions were taken, Hydrosystem was applied to the maxillary left or right premolar teeth, allocated at random, in 50 subjects. The untreated side acted as a control for each subject. The impressions were examined for quality of reproduction and number of surface defects. Hydrosystem was found to significantly improve the quality of reproduction.     

Unstable plastic flow in the deformation of laminar materials

Instability in the plastic deformation of laminar materials is theoretically studied. The initial formulas in the analytical model are consistent with the theory of a third contacting body, taking account of the change in the geometric and energy instability of plastic deformation. The basic solution is in good agreement with experimental data on the deformation of laminar aluminum-copper and aluminum-steel composites.     

Paclitaxel and carboplatin in combination in the treatment of advanced non-small-cell lung cancer (NSCLC): a preliminary study

The effects of rigid contact lens material [polymethyl methyacrylate (PMMA) and itabisfluorofocon A] and prism ballasting (0, 1.5, 2.25, and 3 delta) on tear pump efficiency were studied by measuring corneal oxygen uptake rates on the right eyes of six human subjects under three conditions: (1) normal open eye; (2) after 5 min of static (without blinking) wear of the contact lens; and (3) after 5 min of dynamic (with blinking once every 5 s) wear of the same lens. As expected, corneal oxygen uptake rates (i.e., demand for oxygen) measured with the itabisfluorofocon A material were significantly lower (p < 0.0001) than those measured with PMMA under both static and dynamic conditions. Under static conditions, no significant differences were found across materials among the corneal oxygen uptake rates associated with the four amounts of prism ballasting (p = 0.0514). However, under dynamic conditions, significant differences (p < 0.0001) were found across materials among corneal oxygen uptake rates associated with the four amounts of prism ballasting, with the lower amounts of prism ballasting being associated with lower corneal oxygen uptake rates. The changes in the measured corneal oxygen uptake rates from static to dynamic conditions, relative to those measured for the normal open eye, served as an index of tear pump efficiency. There were no significant differences in these changes for the prism amounts studied; however, static condition data were significantly higher than dynamic condition data for the 0 delta and 1.5 delta lenses only, whereas greater amounts of prism ballasting resulted in no reduction in oxygen uptake under dynamic conditions. In addition, significantly greater differences between static and dynamic condition data were found for the PMMA material than for itabisfluorofocon A.     

Burning mouth syndrome (BMS) and the concept of alexithymia--a preliminary study

Twenty women suffering from burning mouth syndrome (BMS) were rated with regard to alexithymic traits, depressive symptoms and anxiety; values were compared to disability level assessed by interviews. Results confirm earlier reports that BMS symptomatology is associated with depression and anxiety. The majority of patients were rated as alexithymic and, supported by interview data; these results indicate that somatization should be taken into consideration during clinical evaluation of BMS symptoms. The study included a psychological analysis of the communication pattern in the patient-doctor relationship, leading to the assumption that the patient's appeal for somatic treatment, dependency and hopelessness may activate defensive reactions in the dentist. Such reactions can be either rejection of, or compliance with, the patient's demands. The importance of a differentiated assessment and treatment approach for these patients is emphasized. Due to lack of control data the report should be viewed as a pilot study.     

Use of recycled materials in pig-iron production at a non-integrated metallurgical plant

Slags of the required basicity are obtained in blast furnaces at the Lipetsk Metallurgical Plant by adding raw fluxes (limestone and dolomite) to the charge in amounts of 200–300 kg/ton pig iron. Decomposition of the carbonates of calcium and magnesium in these fluxes requires a considerable amount of heat and increases coke consumption in the smelting operation by 45–65 kg/ton pig. To replace the limestone in the charge, the plant uses crushed rock obtained from converter slag. The rock is delivered by the Novolipetsk Metallurgical Combine and is of the 40–70 mm fraction. Most of the economic benefit from using converter slag stems from the replacement of a raw flux (limestone) by lime present in the slag in free form and in the form of compounds-mainly calcium silicates. An equally important factor that affects the cost-effectiveness of using converter slag in the blast-furnace charge is the slag’s 20% iron content. A substantial percentage of the iron in the slag is in the form of FeO and metallic inclusions. __________ Translated from Metallurg, No. 4, pp. 38–42, April, 2007.