A German-Swedish collection of histopathological slides from 1893.

A collection of 159 histopathological slides from 1893 was studied as to origin, condition and documentary value. The slides were dated in Leipzig, Germany, September 26-October 10, 1893. They had apparently been studied jointly by a Swedish veterinary surgeon (Knut August Hjalmar Dahlström) and one or several unknown German colleagues of his in Leipzig, and labelled with their diagnoses. In this paper the collection is referred to as the Leipzig collection. The majority of the slides were well preserved. They reflect part of the animal disease situation, and in some instances also human diseases. Some interesting cases are briefly presented in this paper, one of them even in this abstract, i.e. a case of embryonal nephroma in pig. Six years before Wilms in 1899 described this tumour in children, and 14 years before Day in 1907 described the first case in pig, our then colleagues failed to recognize the embryonic character of the tumour. Their diagnosis was renal adenoma. About 80 percent of the slides were diagnosed as done according to present day procedure. The quality of the slides and that of the diagnostic skill of which they bear witness certainly reflect the far-reaching progress that was made in the knowledge of the nature of diseases and their causes during the second half of the 19th century.

Noise-induced threshold elevation as a function of peak sound pressure level.

Thirty-three groups of guinea pigs, consisting of five animals in each group, were exposed to a simulated impact noise with peak levels ranging between 119.5 and 134.5 dB SPL. By varying the repetition rate, different equivalent levels could be set at each peak level. The equivalent levels ranged from 96 to 117 dB SPL, and the exposure duration was 1.5 to 24 hours. The compound action potential thresholds were measured in 1/3-octave steps between 1 and 20 kHz, one month after the exposure. Higher peak levels resulted in a peak-shaped threshold elevation with a maximum around 8 kHz. For constant peak levels, the equal energy theory was supported. For exposures of equal energy but different peak levels, significantly higher threshold elevations resulted after exposure to higher peak levels.

Infections with Francisella tularensis biovar palaearctica in hares (Lepus timidus, Lepus europaeus) from Sweden.

The occurrence of tularemia was studied in 1,500 hares submitted to the National Veterinary Institute, Uppsala, Sweden for postmortem examination during 1973 through 1985. A total of 109 tularemia cases was recorded based on the fluorescent antibody (FA) test for Francisella tularensis and on the gross and microscopic pathology. Tularemia was diagnosed only in the varying hare (Lepus timidus) and not in the European brown hare (Lepus europaeus). The geographical distribution of the 109 cases indicates that tularemia has not spread in Sweden during the last 45 yr, with the exception of an endemic occurrence of the disease on the island of Stora Karlsö in the Baltic sea. The disease was most frequent in the autumn and only a few cases were recorded during winter. Cases were not seen in the spring. The annual prevalence varied, with several cases in 1974 and 1981, but there were no cases in 1976 and 1980. The postmortem findings in hares dying of tularemia in the autumn were characterized by focal coagulative necrosis in liver, spleen and bone marrow, with high numbers of bacteria FA-positive for F. tularensis. In hares dying during winter months, the most characteristic findings were hemorrhagic enteritis and typhlitis, although necrotic lesions could occur in liver, spleen and bone marrow. Diseased hares on the island of Stora Karlsö were demonstrated to be infected with ticks, while hares on the mainland of Sweden generally were fed upon by mosquitoes. Twenty-six of the 109 hares with tularemia were examined bacteriologically and F. tularensis biovar palaearctica was isolated from eight. The lung extract antibody test for F. tularensis was performed in 18 of the 109 hares. All were negative. In addition to the field study, an experimental study with F. tularensis biovar palaearctica was performed. Four varying hares and three European brown hares were inoculated. None of the hares died from tularemia, and generalized infection was not demonstrated.

[Ethmoid tumors in moose and roe deer]. / Silbenstumörer hos älg och rådjur.

Ethmoid tumors are expansively-infiltratively growing tumors of carcinomatous or sarcomatous nature, deriving from the mucous membrane of the ethmoid bone. In Sweden, such tumors were found in 35 elks (Alces a. alces) and 4 roe deer (Capreolus capreolus) during the years 1947-1982, that means a frequency of about 1 and 0.1 per cent, respectively of the investigation material. However, in the free living elk and roe deer population, the frequency might be much lower. The tumors were malign, extensively melting the soft and hard tissues of the ethmoid region, breaking into the brain cavity, the forehead subcutaneous tissues, etc. Symptoms as suppurative or bloody discharge at the nose, external outline aberrations and disorders to be related to injuries of the central nervous system were observed. In the elk, ethmoid tumors were found only in female animals. In the beginning of this century, ethmoid tumors were found in a number of cattle and horses in Sweden and Norway. Multiple cases occurred in some herds indicating that the tumors were caused by an infectious agent. Since the year 1916, there seem to be no reports on the finding of ethmoid tumors in domestic animals in the Nordic countries. In 1960, however, such tumors were discovered in Indian cattle in Kerala in the south of India. Tumor tissue from the cattle was examined and a herpes-virus was found. Geographically, the distribution of the tumor cases in cattle and elk was very similar in Sweden indicating a possible mutual transmission. As the tumors obviously have disappeared from cattle but not from the elk, it seems likely that the elk might be the primary carrier of the ethmoid tumor. Ethmoid tumors have been observed for many years in Scandinavia but only rather recently they were discovered in India. It has been known for long that birds after contamination might be involved in the spread of virus diseases, provided the virus are reasonably resistant. In the actual case, the suspicion has mainly been directed at three bird species, viz. the blue throat (Luscinia svecica), the scarlet grosbeak (Erythrina erythrina) and the red-necked phalarope (Phalaropus lobatus). In spring and summer, these birds periodically reside in elk habitat where they might be contaminated. In the autumn, they may extend their migration to the southern parts of India.

Hyperplastic and neoplastic changes in ultimobranchial remnants and in parafollicular (C) cells in bulls: a histologic and immunohistochemical study.

Thyroid glands from 64 bulls with hyperplastic and/or neoplastic changes in ultimobranchial remnants and in the parafollicular (C) cell system were studied structurally and with immunohistochemical methods. Antibodies against thyroglobulin, calcitonin, somatostatin, and neurotensin were used to detect these substances. Two different types of changes were observed. One change was hyperplasia and neoplasia of the ultimobranchial remnants that affected all their epithelial constituents. These included ultimobranchial follicles, cysts and tubules, as well as solid nests formed by basophilic immature cells which were functionally undifferentiated and unreactive with all the antisera used. Differentiated follicular cells that formed thyroid follicles and cribriform structures with immunohistochemical evidence of thyroglobulin production were also found. In addition, differentiated light and cytoplasm-rich cells were scattered in the walls of the thyroid follicles, ultimobranchial follicles, cysts and tubules as well as in the solid component. They were argyrophilic and reacted with antibodies against calcitonin and somatostatin. The other change was a diffuse or multifocal hyperplasia of the parafollicular (C) cells that was present in other parts of the thyroid parenchyma--sometimes with gradual development of sclerotic tumors that had been exclusively formed by these cells. They corresponded to light cytoplasm-rich cells seen in the ultimobranchial lesions that were argyrophilic and harbored material reactive with antibodies against calcitonin and/or somatostatin. The changes observed in the parafollicular cell system resembled lesions seen in human thyroid glands with the familial variant of medullary carcinoma as well as those reported in thyroid glands of patients with longstanding hypercalcemia.(ABSTRACT TRUNCATED AT 250 WORDS)

Determination of optical constants from intensity measurements at normal incidence.

The reflection-transmission method for determining the optical constants of a film on a substrate has been examined and a computer program for the solution of the equation system has been written. A new method involving only transmittance data in a limited wavelength region has been worked out and has been found to give accurate results. The computer program for this method gives directly n and k curves from the transmission curve.