Prognostic factors for feline mammary tumors

The case records of 100 cats with malignant mammary tumors were reviewed. All cats were staged clinically according to the staging system of the World Health Organization. The following information was obtained from the medical records: age at time of diagnosis, breed, tumor size, date of surgery, type of surgical procedure performed, histologic type of tumor, disease-free interval, survival time, and cause of death. Factors of no prognostic value were age (less than or equal to 10 years vs greater than 10 years) and breed. Tumor size was the most significant prognostic factor (P less than 0.0001). Cats with small tumors (1 cm3 to 8 cm3) had the best prognosis. The type of surgery, conservative vs radical, was significantly (P less than 0.01) related to disease-free interval, but was of no significance in prolonging survival time.     

Acquired immunity to Fasciola hepatica in splenectomised rats.

Significant resistance to a second infection with Fasciola hepatica was obtained in splenectomised and sham operated rats (P less than 0.001, 78 and 76 per cent respectively) when compared with singly infected splenectomised or sham operated control groups. For both the stimulating and challenge infections, there were no significant differences in the number of flukes recovered from rats that had been splenectomised as compared to those receiving the sham operation. Thus, splenectomy did not significantly affect the ability of rats to develop an acquired immunity to F hepatica, nor were fluke recoveries from a particular schedule of infection significantly affected by the presence of absence of a spleen. It is concluded that the presence of a spleen is not necessary for the development of acquired immunity to F hepatica in the rat.     

In vitro cytopathic effects of a cysteine protease of Tritrichomonas foetus on cultured bovine uterine epithelial cells

OBJECTIVE: To evaluate the cytopathic effects of Tritrichomonas foetus and a purified cysteine protease (ie, CP30) of T foetus on cultured bovine uterine epithelial cells (BUECs) in vitro. SAMPLE POPULATION: 10 reproductive tracts were obtained from late-term bovine fetuses at a commercial abattoir. PROCEDURE: An in vitro culture system of BUECs was developed to study the cytopathic effects of T foetus and purified CP30 of T foetus on host cells. Cytotoxicity of T foetus or CP30 on exposed BUECs was determined. Fluorescence microscopy and flow cytometry analyses were used to detect apoptosis. A fluorometric assay was used to detect BUEC caspase 3 activation. The CP inhibitor E-64 and a caspase inhibitor were used to inhibit apoptosis. RESULTS: Cytopathic effects were observed in BUECs treated with parasites or CP30 and were concentration and time dependent. The BUECs underwent apoptosis in the presence of parasites or CP30. The specific CP inhibitor E-64 abolished the induction of apoptosis in BUECs by CP30. The caspase inhibitor reduced the amount of apoptosis in BUECs. CONCLUSIONS AND CLINICAL RELEVANCE: T foetus and its CP30 induce apoptosis in cultured BUECs in vitro. Induction of apoptosis by CP30 is correlated with protease activity. Endometrial cell death as a result of a T foetus infection is likely to be more important in mediating infertility than a direct effect on the conceptus. Provoking an apoptotic reaction in the host may mitigate an inflammatory reaction or immune response and therefore favor survival of the parasite in a chronic infection.     

Renal lymphoma in cats: 28 cases (1977-1984)

Renal lymphoma was diagnosed, staged, and treated in 28 cats. Renal lymphoma staging was done according to clinical findings: 11 cats had stage-2 lymphomas, 5 had stage-3 lymphomas, 6 had stage-4 lymphomas, and 6 had stage-5 lymphomas. All cats were treated with chemotherapy: 17 cats had a complete response, 9 cats had a partial response, and 2 cats had no response. The cats with stage-2 lymphomas that were FeLV-test negative had the best response to treatment.     

Owners' perceptions of the health and performance of Pony Club horses in Australia

Pony Club is one of the leading junior equestrian organisations in the world, and was established to teach young people the many aspects of horsemanship. The aim of this study was to gain an understanding of the health and performance of Pony Club horses from the perspective of their owners. In-depth interviews were conducted with Pony Club members at two sites in Australia, and topics relating to participants' background with horses, horse attributes valued by participants, horse health and performance, and Pony Club-related matters. The in-depth interviews were taped, transcribed and analysed, by describing the themes and issues recorded in the dialogue and conducting cross-case analysis (finding similarities and dissimilarities between participants with respect to each of the above-mentioned topics). A total of 32 interviews were conducted. The participants' background with horses varied greatly. The horse attributes valued by > or =59% of participants included temperament, size, ability and suitability for riders. A range of issues relating to health and performance were important to > or =53% of participants, including horse temperament, nutrition, internal parasites, lameness and foot-care, and colic. Soundness and preventive health measures were rarely mentioned (< or =16% of participants). Friends or knowledgeable horse people were identified as the first point of contact for horse-health matters, and veterinarians were only used as a last resort or for serious problems. Members of Pony Club learned about their horses by trial and error. Optimal performance was described as a horse that was willing to do as the rider asked. Poor performance was usually the result of the horse misbehaving, and could include a resistance to rider commands, pigrooting and bucking.     

Optical spectroscopy of individual single-walled carbon nanotubes of defined chiral structure

We simultaneously determined the physical structure and optical transition energies of individual single-walled carbon nanotubes by combining electron diffraction with Rayleigh scattering spectroscopy. These results test fundamental features of the excited electronic states of carbon nanotubes. We directly verified the systematic changes in transition energies of semiconducting nanotubes as a function of their chirality and observed predicted energy splittings of optical transitions in metallic nanotubes.