Histologic perspective adds dimension to evaluating pocket measurements

The paper deals with the complex presentation of data for endoscopic studies on personal computers for the benefit of a physician in drawing up medical documents, establishing an accurate diagnosis, preparing a treatment regimen, as well as in facilitating his work, storing and processing data, searching for reference information, drawing up the dynamics of morbidity and its prediction. A scheme for complex presentation of the information required for endoscopic studies is given.     

Hepatocyte proliferation and gene expression induced by triiodothyronine in vivo and in vitro

Subcutaneous injections of hormone triiodothyronine in rats resulted in peak blood levels at 24 hr with return to baseline by 96 hr. The injections stimulated a liver regeneration response that resembled in timing and in magnitude of DNA synthesis (peak, 24 hr) that induced by 40% hepatic resection. The principal proliferation was of hepatocytes. Although there were some temporal differences from the gene expression of transforming growth factor-alpha, transforming growth factor-beta, and c-Ha-ras that are known to follow partial hepatectomy, the overall profile of these changes was similar to those after partial resection. The effect was liver specific and could be reproduced three times with no diminution in response in the same animal with injections at 10-day intervals. No response was detected in kidney or intestine. This effect in intact animals contrasted with the minimal ability of triiodothyronine to stimulate hepatocytes in culture. However, when the culture medium was enriched with epidermal growth factor, there was a dose-related response to triiodothyronine. The totality of these experiments provides a preliminary basis for the creation with pharmacological techniques of an in vivo hyperplastic hepatic condition permissive of transfection of new genes, as an alternative to partial hepatectomy. Although triiodothyronine was the test agent used, other hepatic growth factors singly or in combination could be candidates for this purpose.     

Placental transfer and maternally acquired neonatal IgG immunity in human immunodeficiency virus infection

PURPOSE: The effect of the sensitizer razoxane on soft tissue sarcomas (STS) was prospectively evaluated in a randomized, controlled trial. The main purpose of the study was to determine the response rates and local control under the combined treatment compared to irradiation alone. METHODS AND MATERIALS: Between 1978 and 1988, 144 patients entered the study; 130 were evaluable for response, toxicity, or survival. The patients were randomized to receive radiotherapy alone or radiotherapy with razoxane. They were divided into postoperative cases and patients with gross disease (unresectable primaries, recurrent disease, or metastatic disease). The median radiation dose was 60 Gy postoperatively, and 56-58 Gy in patients with gross disease. The dose difference has palliative reasons. Razoxane was given orally at a daily dose of 150 mg/m2 during the time of the radiotherapy, starting 5 days before the first irradiation. In general, the groups were comparable as to their prognostic factors. There was some imbalance, however, in favor of the postoperative group reveiving radiotherapy alone. RESULTS: Between the patient groups treated postoperatively in an adjuvant form, there were no substantial differences in local control and survival. Among 82 patients with gross disease, the treatment with radiotherapy and razoxane led to an increased response rate compared to photon irradiation alone (74 vs. 49%). The local control rate was likewise improved (64 vs. 30%;p < 0.05). The acute toxicity was somewhat higher in the sensitizer arm, but there was no difference in the occurrence of late complications. CONCLUSIONS: Radiotherapy combined with razoxane seems to improve the local control in inoperable, residual, or recurrent STS compared to radiotherapy alone. The combined treatment is a fairly well tolerated procedure at low costs. It can be recommended for inoperable primary STS or gross disease after incomplete resection, conditions which are still associated with limited local control and a grave prognosis.     

Porcine aortic leaflet arrangement may contribute to clinical xenograft failure

Clinical experience with the first generation porcine xenograft shows significant deterioration and mechanical failure after 7-8 years post-implantation. Although many mechanisms of valve failure have been identified, the inherent differences between porcine and human aortic valves have not been emphasized. To determine if these differences are significant, the authors studied the anatomy of the aortic valve in 10 post-mortem porcine hearts. The authors found that the non-coronary leaflet was the smallest and the right leaflet was the largest based on the dimensions of area, perimeter, weight, and attached edge length (p < 0.05). These results differ from reported analyses of human aortic valves, in which the smallest cusp is generally the right the largest is the non-coronary. The authors believe that these differences between the human and porcine aortic valves may result in atypical mechanical stresses and the disruption of blood flow patterns in the sinuses of Valsalva, and may decrease the long-term stability of the porcine bioprostheses. In other words, the failure found with porcine bioprostheses after 8 years of implantation might be expected from the inherent structure (and associated fluid dynamics) of the porcine aortic valve positioned in the human aortic root.     

The participation of mast cells and serotonin-immunoreactive fibers in the innervation of the cerebral vessels

Interrelations between adrenergic and serotoninergic nerve fibres and mast cells located near the vascular wall were studied on total preparations of rat brain pia mater. Histochemical method with glyoxylic acid revealed the dense network of adrenergic fibres and their terminal regions with variceal endings with mast cells located next to them. Immunohistochemical methods (fluorescent and method with use of peroxidase antiperoxidase complex) with the aid of antiserum serotonin showed the content of serotonin in these cells. Distribution of serotoninergic nerve fibres resemble that of adrenergic fibres with density being significantly lower. The fibres have frequent contacts with mast cells processes. These data indicate the presence of functional connection between serotonin positive nerve fibres and the possibility of their drawings in control of blood circulation of brain.     

Dry chemistry instruments in primary care. I. Operating conditions and financial considerations

The objectives of this study were to describe the operating conditions of dry chemistry instruments in primary care, as well as to elucidate financial aspects in general practice fee-for-service settings. We used questionnaires mailed to all users of the two most used dry chemistry instruments in Norway, as well as to a 14% random sample of Norwegian GPs. The overall response rate was 79%. The mean number of dry chemistry analyses varied considerably between individual users, but in general a substantial number of analyses were carried out. Even though most analyses on the instruments' repertoire were available in all user groups, a total of 13 additional constituents were suggested to be included in the repertoire. In occupational health care most results were ready when the client was present; this was not the case in general practice. The instruments were more profitable when more constituents were analysed per sample, although profitability varied substantially in the period studied (1986-1989). A discrete time history event analysis revealed that net profit earned, lower instrument price, available information about the technology and being in solo practice significantly influenced the decision to buy an instrument in fee-for-service practices.     

Amacrine cells in Necturus retina: evidence for independent gamma-aminobutyric acid- and glycine-releasing neurons

About one-half of on-off ganglion cells have inhibitory postsynaptic potentials (IPSP's) which are blocked by strychnine, while the remainder have IPSP's which are blocked by picrotoxin or bicuculline. These antagonists do not abolish light activity of the presynaptic inhibitory neuron, the amacrine cell. The existence of separate gamma-aminobutyric acid- and glycine-releasing amacrine cells is implied by these results.