Mortality among different occupational groups of workers with pneumoconiosis: Results from a register-based cohort study

A mortality cohort study was carried out on 11,224 men with pneumoconiosis diagnosed during the period 1970–1985. The cohort was selected from among subjects entered into the National Register of Occupational Diseases and included 7,065 coal miners, 924 employees of underground work enterprises, 1,796 workers of the metallurgical industry and iron and nonferrous foundries, as well as 1,439 refractory materials, china, ceramics, and quarry workers. The cohort was traced up to the end of 1991. The mortality of all groups enrolled in the study, as compared with that of the general male population of Poland, showed a statistically significant excess of overall mortality (SMRs ranging from 105; 95% confidence interval [CI]: 100–110 to 136; CI: 121–153) as well as a great excess of deaths from diseases of the respiratory system (SMRs from 383; 95% CI: 345–424 to 588; 95% CI: 457–744). In workers of the metallurgical industry, foundries, and those from refractory materials, china, and ceramics manufacturing plants as well as quarries, a statistically significant excess of deaths from infectious diseases (mostly tuberculosis) was found (SMRs: 503; 95% CI: 364–677 and 286; 95% CI: 177–437, respectively). Mortality from lung cancer as significantly elevated only in the group of metallurgical industry and iron and nonferrous foundry workers (SMR: 159; 95% CI: 124–201). In the remaining subcohorts, no significant excess of deaths from lung cancer was noted. The study does not support the hypothesis on the role of exposure to crystalline silica in the induction of lung cancer. Significantly lower mortality was seen for diseases of the circulatory system (SMR: 89; 95% CI: 82–96), hypertensive disease (SMR: 63; 95% CI: 38–98), cerebrovascular disease (SMR: 79; 95% CI: 62–99), atherosclerosis (SMR: 79: 95% CI: 66–93), and injuries and poisonings (SMR: 50; 95% CI: 38–64) in coal miners. In addition, lower mortality was noted for cerebrovascular disease (SMR: 56; 95% CI: 32–91) and injuries and poisonings (SMR: 34; 95% CI: 17–61) in metallurgical industry and iron and nonferrous foundry workers. © 1996 Wiley-Liss, Inc.     

Regional differences in extracellular ascorbic acid levels in the rat brain determined by high speed cyclic voltammetry

High speed cyclic voltammetry was used in combination with pressure ejection of ascorbate oxidase for the determination of extracellular ascorbic acid within the brain of the anaesthetized rat. Large variations in absolute levels of ascorbate were found between animals although distribution patterns showed a good degree of reproducibility. Ascorbate levels in the white matter of the corpus callosum were found to be higher than in adjacent areas of grey matter (striatum and cortex).     

Concentration-dependent HAT/ET mechanism of the reaction of phenols with 2,2-diphenyl-1-picrylhydrazyl (dpph˙) in methanol

The reaction of a 2,2-diphenyl-1-picrylhydrazyl radical (dpph˙) with phenols carried out in alcohols is a frequently used assay for estimation of the antiradical activity of phenolic compounds. The rates of reactions of dpph˙ with five phenols (ArOH: unsubstituted phenol, 4-hydroxyacetophenone, two calix[4]resorcinarenes and baicalein) measured in methanol indicate the different kinetics of the process for very diluted phenols compared to their non-diluted solutions. This effect was explained as dependent on the ratio [ArO⁻]/[ArOH] and for diluted ArOH corresponds to an increased contribution of much faster electron transfer (ET, ArO⁻/dpph˙) over the Hydrogen Atom Transfer (HAT, ArOH/dpph˙). Simplified analysis of the reaction kinetics resulted in estimation of k^ET/k^HAT ratios for each studied ArOH, and in calculation of the rate constants k^ET. Described results are cautionary examples of how the concentration of a phenol might change the reaction mechanism and the overall kinetics of the observed process.

Concentration dependent contribution of hydrogen atom transfer and electron transfer to the overall kinetics of reaction of phenols with a 2,2-diphenyl-1-picrylhydrazyl radical in methanol.     

Modified Histopathological Protocol for Poly-ɛ-Caprolactone Scaffolds Preserving Their Trabecular,Honeycomb-like Structure

Poly-ɛ-caprolactone (PCL) is now widely studied in relation to the engineering of bone, cartilage, tendons, and other tissues. Standard histological protocols can destroy the carefully created trabecular and honeycomb-like architecture of PCL scaffolds, and could lead to scaffold fibers swelling, resulting in the displacement or compression of tissues inside the scaffold. The aim of this study was to modify a standard histopathological protocol for PCL scaffold preparation and evaluate it on porous cylindrical PCL scaffolds in a rat model. In 16 inbred Wag rats, 2 PCL scaffolds were implanted subcutaneously to both inguinal areas. Two months after implantation, harvested scaffolds were first subjected to μCT imaging, and then to histopathological analysis with standard (left inguinal area) and modified histopathological protocols (right inguinal area). To standardize the results, soft tissue percentages (STPs) were calculated on scaffold cross-sections obtained from both histopathological protocols and compared with corresponding µCT cross-sections. The modified protocol enabled the assessment of almost 10× more soft tissues on the scaffold cross-section than the standard procedure. Moreover, STP was only 1.5% lower than in the corresponding µCT cross-sections assessed before the histopathological procedure. The presented modification of the histopathological protocol is cheap, reproducible, and allows for a comprehensive evaluation of PCL scaffolds while maintaining their trabecular, honeycomb-like structure on cross-sections.     

An ultrasonographic monitoring of skin condition in patients receiving radiotherapy for head and neck cancers

Radiodermatitis is one of the commonest side effects of radiotherapy. They are usually assessed by semi‐quantitative clinical scores, which are not validated and may be subject to inter‐observer variability. A few previous studies suggested that high‐frequency ultrasonography (HF‐USG) is useful in the assessment of the acute phase of radiation dermatitis in breast cancer patients. (a) To monitor skin changes by HF‐USG during the course of radiotherapy due to head and neck cancers, and (b) to determine whether there is any connection between skin sonograms and the skin scoring criteria. This prospective, observational study includes patients diagnosed with head and neck cancers, treated with radiotherapy or concomitant chemoradiation. The final analysis includes six patients. In every patient, the HF‐USG as well as dermatological assessment (target lesion score—TLS and CACE v. 4.0) were performed 4×: before, in the middle, day after, and 3 months after radiotherapy. There were significant differences between non‐irradiated skin thickness and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P < .0001), as well as between irradiated, unchanged skin thickness (TLS grade 0) and thickness of skin with clinically obvious radiodermatitis (TLS grade 1‐4; P = .0002). There was no significant difference between non‐irradiated and irradiated, unchanged skin thickness (TLS grade 0; P = .9318). In four patients, we demonstrated subepidermal low echogenic band (SLEB). HF‐USG can be useful tool to noninvasive and objective assessment of skin changes during radiotherapy.     

Effects of 21 days treatment with fluoxetine on stimulated endogenous 5-hydroxytryptamine overflow in the rat dorsal raphe and suprachiasmatic nucleus studies using fast cyclic voltammetry in vitro

Changes in the extracellular concentration of 5-HT evoked by electrical stimulation of brain slices containing either dorsal raphe nucleus (DRN) or suprachiasmatic nucleus (SCN) from rats treated for 21 days with fluoxetine (5 mg/kg; i.p.) or water were monitored using fast cyclic voltammetry (FCV). Stimulated 5-HT overflow was enhanced significantly in both brain regions after 21 days treatment with fluoxetine but there was no change in the half time for re-uptake (t1/2). Concentration response curves for inhibition of electrically stimulated 5-HT overflow by 8-OH-DPAT (5-HT_1a receptor agonist) or RU24969 (5-HT_1b receptor agonist) in the DRN or SCN respectively were obtained in slices prepared from both groups of animals. There was a significant shift to the right in the dose-response curve for RU24969 in the SCN in fluoxetine treated animals but a shift to the left for the dose-response curve for 8-OH-DPAT in the DRN. These data suggest that down regulation of the 5-HT_1b autoreceptors occurs in an axon terminal region (SCN) but that there is a sensitisation of 5-HT_1a autoreceptor mechanisms controlling 5-HT overflow in the DRN.     

The Rorschach method as a prognostic aid in the insulin shock treatment of schizophrenics

Psychiatric Quarterly -     

Existence of automaticity in anomalous bundle of Wolff-Parkinson-White syndrome.

Escape beats probably arising from the anomalous bundle were documented in 2 patients with the Wolff-Parkinson-White (WPW) syndrome. A third patient, in whom complete AV block developed both in the anomalous bundle and the normal pathway, showed the occurrence of escape beats (an escape-bigeminy pattern), as well as a regular idioventricular rhythm arising from the anomalous bundle. Phase 4 block in the anomalous bundle occurred in 7 other patients, in 4 of them spontaneously and in 3 only after the administration of ajmaline or amiodarone. Only 4 of 14 fully investigated patients (out of a total number of 23) showed absence of both escape beats and phase 4 block. The escape beats were considered as direct evidence, and the phase 4 block as indirect evidence, for the existence of automaticity in the anomalous bundle. Such evidence supports the view that the anomalous bundle, like the His bundle-branch system, may be composed of specialised tissue endowed with the property of automaticity.