The excretion of Salmonella typhimurium in the faeces of calves fed milk substitute

A total of 495 calves in 16 batches were examined (117 calves in 4 batches in 1979 and 378 in 12 batches in 1982). They were purchased in markets, transported by road to a farm in Somerset and reared on a milk substitute diet for a period of up to five weeks. Salmonella typhimurium phage type DT 193 was endemic in 1979 and phage type DT 204c in 1982. The mortality rates in the two years were 9.4% and 1.9% respectively. The causes of death were not investigated although the majority were probably due to salmonellosis. The rate of isolation of S. typhimurium from the rectal faeces of calves in all groups was either zero or relatively low on arrival. It rose to a peak (which was higher in 1979) in the second or third weeks before declining to low levels by the end of the fourth week of residence on the farm. Data from 162 calves, examined twice weekly for four weeks in 1982, indicated that the distribution of infected calves, based on the number of times that S. typhimurium was isolated from each, was not random. The calves could be assigned to two main categories; those from which the organism was never isolated and those from which it was isolated at least twice. This suggested that salmonella infected calves actively excreted the organism. The association between salmonella excretion and medication of sick animals with antibacterial drugs was strongest during the second week. Over the four-week period nearly 40% of the calves found to be excreting S. typhimurium were not treated, indicating a high incidence of subclinical infection. Salmonella excretion by the calves followed a regular pattern and infection was self-limiting within five weeks. The peak in the salmonella excretion rate and the mortality rate were higher in 1979 when phage type DT 193 was the endemic strain. However, in 1982 the calves received 100 p.p.m. furazolidone in their milk ration during the first week of their stay on the farm, and this may have contributed to the differences noted between the two years.     

Adenocarcinoma of the kidney. II. Enzyme histochemistry of renal adenocarcinomas induced in rats by N-(4'-fluoro-4-biphenylyl)acetamide.

Activities of a broad spectrum of enzymes were studied histochemically in renal adenocarcinomas induced in young male F344 rats by chronic dietary administration of the carcinogen N(4'-fluoro-4-biphenylyl)acetamide. Enzymes included were: dehydrogenases of glucose-6-phosphate, lactate, succinate, malate, and alpha-glycerophosphate; peroxidase (catalase); glucose-6-phosphatase; alkaline and acid phosphatase; Mg2+ ATPase; 5'-nucleotidase; and aminopeptidase. Levels of enzyme activity were estimated visually and scored from 0 (not detectable) to a maximum of 5 (intense). Comparison of estimated activity for each enzyme was made between small neoplastic nodules (stage III tumors) and large adenocarcinomas (stage IV tumors) and between tumors and portions of normal proximal tubules in parenchyma of kidneys from untreated control rats. The results, which revealed nearly identical levels of activity for most enzymes in both stages III and IV tumors, suggested similar metabolic and biologic behavior of these lesions. However, when data for tumors were compared with data for normal proximal tubules, striking differences were observed consistent with: 1) a marked shift of energy metabolism from oxidative to glycolytic production of ATP, with a corresponding reduction in mitochondrial respiration; and 2) simplification of plasma membrane specializations that were possibly associated with a reduction or loss of transport function. These findings were compared with other histochemical, biochemical, and ultrastructural studies of renal adenocarcinomas in rats and man.     

Plasma catecholamines, stress and aggression in maximum security patients

Investigations into the stress response of patients committed to a special hospital for criminally deviant offences have identified a group of sympathetically hypoactive patients who excrete more noradrenaline and less adrenaline in the urine than either the remaining hospital population or control subjects, during conditions of stresser anticipation. Further investigation of these patients has shown that similar differences in plasma catecholamines exist, and that the group of patients characterised by this imbalance tend to have been committed for the most physically violent crimes.     

Phase II study of paclitaxel plus gemcitabine in refractory germ cell tumors (E9897): a trial of the Eastern Cooperative Oncology Group.

PURPOSE: Despite great success in the treatment of disseminated germ cell tumors, 20% of patients are incurable and become candidates for investigational therapy. Paclitaxel and gemcitabine have shown activity as single agents in refractory germ cell tumors and can be combined with manageable toxicity. PATIENTS AND METHODS: Patients with germ cell tumors believed to be incurable with chemotherapy or surgery were treated with paclitaxel 110 mg/m(2) and gemcitabine 1,000 mg/m(2) intravenously on days 1, 8, and 15 of a 4-week cycle for a maximum of six cycles. Patients were evaluated for response and toxicity. RESULTS: Twenty-eight of 30 enrolled patients were assessable. Toxicity was primarily hematologic but was manageable with only a single case of neutropenic fever. Six (21.4%) of 28 patients responded, including three complete responses. Two of the complete responders were continuously disease-free at 15+ and 25+ months. CONCLUSION: Paclitaxel plus gemcitabine is an active regimen in refractory germ cell tumors, with an acceptable toxicity profile. This regimen has the possibility for long-term disease-free survival in this refractory patient population.     

Mucosubstance histochemistry in control and acid-stressed epidermis of brown bullhead catfish,lctalurus nebulosus (LeSueur)

Glycoprotein components of epidermal mucous cells in control (pH 6.8) and acid-stressed (pH 5.8, 4.8, 4.0) brown bullhead catfish were studied by histochemical and autoradiographic methods. Following exposure to acid, increased numbers of epidermal mucous cells were noted in all tissue sites studied, particularry dorsal and ventral skin. Mucous cells of control fish and acid-stressed (pH 5.8) fish contained a mixture of neutral and acidic mucosubsf ances, the latter including both sialomucins and sulfomucins, with sialomucins predominating. An apparent shift toward increased sulfomucin production was observed in skin from fish exposed to pH 4.8 and 4.0. In addition, autoradiographic studies using ³⁵S showed increased labeling of mucous cells in acid-exposed (pH 4.0) epidermis, offering further support for a shift toward sulfomucin production in acid-stressed fish. Absence of appreciable sulfomucin production in younger fish (<1 year old) suggested that this shift may be partly age-dependent. The functional significance of increased sulfomucin production in acid-stressed epidermal mucous cells is uncertain but may be related to maintenance of ionic equilibrium.     

The persistence of drug resistant Escherichia coli strains in the majority faecal flora of calves

Two groups of calves, one of three and the other of two animals, were purchased in markets and reared initially on a commercial veal unit for 1 month and 4 months respectively. They were then moved to the Veterinary School, Langford, and kept for a further 6 and 4 months respectively. The animals were sampled weekly and a continual turnover in the strains forming the majority Escherichia coli faecal flora was demonstrated for all calves. Antibacterial-drug resistance, as measured by an Antibiotic Resistance Index (ARI), increased after arrival on the veal unit and persisted at high levels during the whole of their stay. After moving to Langford the ARI fell. Initially there was a reduction in the average number of resistance determinants per resistant strain and then, after a delay of up to 8 weeks, by an increase in the proportion of isolates that were fully sensitive. The source of the sensitive strains was not ascertained, although their appearance was not associated specifically with either weaning or turning out to pasture.