Long-term urethral catheter drainage

Long-term catheter management is best conducted by specially trained community staff, provided there is close liaison with the urologist. Patients, hospital staff, and the primary health care team all benefit. The scheme is cost-effective, more convenient for patients and relatives, and reduces the need for emergency calls to the general practitioner and hospitals. We advocate development of similar schemes in other districts.

Ascorbic acid-dependent collagen formation in penaeid shrimp

1. This study tested the hypothesis that black death, the ascorbic acid (AsA) related disease of penaeid shrimp, is related to collagen underhydroxylation. 2. Collagen measured as hydroxyproline (HYP) in healthy Penaeus californiensis (Holmes) and P. stylirostris (Stimpson) of a wide range of masses were determined. The results revealed a logarithmic relationship between total body collagen HYP and body weight fitting the equation y = 90x1.18 where y = total collagenous HYP (microgram) and x = body weight (g). 3. Shrimp tissues most subject to mechanical trauma (subcutis, hindgut and gills) had the highest collagenous HYP levels and were most consistently and severely affected by an ascorbic acid (AsA) deficiency disease. 4. Prolyl hydroxylase (PH) activity was demonstrated in tissues of P. californiensis and P. stylirostris by hydroxylation of [3,4-3H]proline. 5. AsA was required for shrimp PH activity using a chicken embryo substrate. 6. Nutritional trials revealed that dietary AsA was required for proline hydroxylation in collagen formation in P. californiensis.

The oral toxicity of 1-amino-3-chloro-propanol hydrochloride (CL 88236) in rats

1-amino-3-chloro-2-propanol (CL 88236) was administered by oral gavage for 12 consecutive weeks to rats at dose levels of 50, 250 and 500 mg/kg/day. All levels gave rise to toxicological effects. Epididymal necrosis and/or atrophy of the seminiferous epithelium was found for some males with each dose of CL 88236. The kidney and liver weights of male and female rats given CL 88236 were higher than control values but no histological changes were found in these organs.

Demyelinating peripheral neuropathy in a guinea hen associated with subacute lead intoxication

In mammalian species lead acts primarily as a neurotoxin. Lead poisoning is common in avian species but lesions in the nervous system have not been associated with it. This paper describes a peripheral neuropathy with fragmentation and segmental demyelination of fibers in the sciatic nerves of an adult guinea hen (Numida meleagris) which died of lead poisoning.

A simple vascular perfusion technique for use in waterfowl

A simple vascular perfusion technique is described for fixation of avian tissues for study at the light-microscope level. The technique relies on gravity feed of perfusate and gives reliable fixation of the nervous system, liver, kidney, and cardiac and skeletal musculature.

A 2-year retrospective study of demand for dental care from Scottish school leavers

After leaving school young adults in the United Kingdom are no longer eligible to receive care from the School Dental Service. Patients who have previously been treated by the Service are obliged to seek care elsewhere. The aim of the study was to see how effectively a group of Scottish school leavers coped with the change. The study population was 912 school leavers. The method depended upon a retrospective study of clinical records relating to the year before leaving school and the following year. During the last year at school, 48% of the subjects received treatment from three sources: 30% were treated by a general practitioner, 19% by the school service and 2% by the hospital service. During the 2nd year of the study, 69% of those who had earlier been treated by a general practitioner again requested dental care compared with only 40% of those who had earlier been treated by the school service and 30% of those who had not sought dental care during their last year at school. Recommendations are made for encouraging an increased demand for care from those who have formerly been treated by the school service.

A cytological study of micronuclear elongation during conjugation in Tetrahymena

Micronuclear elongation is the first major event in a series of nuclear changes occurring during the sexual stage of the life cycle of Tetrahymena. Beginning at about one hour after cells of complementary mating types have conjugated, the micronucleus leaves its recess in the macronucleus and swells slightly. This is accompanied by a reorganization of its chromatin from a reticular to a solid body. In the next stage the micronucleus assumes an egg shape, a development concomitant with the appearance of microtubules. While the chromatin "spins out" from the dense body, and microtubules increase in number, the nucleus assumes a spindle shape. During the elongation, which increases the length of the nucleus some fifty fold, microtubules are prominent in clusters just internal to the nuclear membrane, and parallel to the longitudinal axis of the nucleus. When elongation is completed the nucleus is curved around the macronucleus. Internally, partially condensed strands of chromatin are located off-center, towards the macronuclear side, and the density of the microtubules is diminished. At all the stages, DNA is located throughout the nucleus; neither discrete chromosomes nor synaptonemal complexes are seen. Occasionally cytoplasmic membrane systems are seen fused to the nuclear envelope which retains the typical appearance of a double membrane with pores.

Long-term toxicity of the surfactant alpha-olefin sulphonate (AOS) in the rat

The surfactant alpha-olefin sulphonate (AOS) was fed to rats at dietary levels of 1000, 2500 and 5000 ppm for a period of 2 years. There were no adverse clinical signs, and survival rates were not affected by treatment with AOS. The rate of bodyweight gain was marginally lower during the second trimester of the study in both males and females receiving 5000 ppm AOS, while food intake was also marginally lower during the first year among females receiving 5000 ppm. During the remainder of the study, bodyweight change and food consumption of all treated animals was similar to that of the control animals. Investigation of the animals' eyes, blood and urine did not reveal any reaction to treatment, nor were any changes relating to treatment seen in the macroscopic pathology or organ weights of rats killed after 104 weeks. Histological examination of the tissues did not provide any evidence of toxicity or tumour induction that could be attributable to treatment with AOS.

Epitheliogenesis imperfecta in a black labrador puppy

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Suppression of sebaceous gland non-specific esterase activity be electrophilic alpha beta-unsaturated compounds

Sebaceous gland non-specific esterase activity was suppressed following application to mouse skin of 2 electrophilic alpha beta-unsaturated compounds, o-chlorobenzylidenemalononitrile and beta-nitrostyrene, but not by three others.

Nonspecific Immunotherapy of Murine Solid Tumors With Corynebacterium granulosum

A single intraperitoneal (ip) or intravenous (iv) injection of Corynebacterium granulosum into C3Hf/Bu mice shortly after subcutaneous (sc) injection of cells from a strongly antigenic syngeneic fibrosarcoma induced by 3-methylcholanthrene caused complete and lasting regressions of 100 and 70% of resulting tumors, respectively. Treatment with this bacterium sc only slightly inhibited the growth of some tumors. C. granulosum given iv to mice 3 days after the sc injection of fibrosarcoma cells caused complete regressions of 39 of 45 tumors; two iv injections with this immunostimulant given 1 month apart were no more effective than a single injection. Intralesional treatment of fibrosarcomas 8 mm in diameter induced complete regressions of tumors in 30% of the animals, whereas sc treatment contralateral to the growing tumor only slightly reduced tumor growth. Intraperitoneal growth of a fibrosarcoma was efficiently controlled (58-80% survival of mice) if C. granulosum was given ip, but not iv, 3 days after inoculation with tumor cells. Again, two injections of C. granulosum (given ip 4 days apart) were only as effective as a single injection. Treatment with C. granulosum iv at 3, 7, 14, or 21 days after sc inoculation of a weakly antigenic, spontaneously arising mammary carcinoma (MC-1) strongly inhibited tumor growth. Three complete but temporary tumor regressions were observed. The subcutaneous growth of another spontaneous mammary carcinoma (MC-2), which contained fairly strong tumor-specific antigen(s), was also significantly inhibited if C. granulosum was given 3,7, or 14 days after, but not 7 days before, tumor cell inoculation. However, pretreatment of mice with the immunostimulant significantly protected the mice against artifically induced pulmonary metastases of this tumor.

Evaluation of the tumorigenic potential of vermiculite by intrapleural injection in rats

Hunter, B., and Thomson, C. (1973).British Journal of Industrial Medicine,30, 167-173. Evaluation of the tumorigenic potential of vermiculite by intrapleural injection in rats. Vermiculite, the geological name for a group of hydrated laminar minerals, has industrial application in areas previously restricted to the use of asbestos. In this assessment of its tumorigenicity, Rhodesian chrysotile asbestos or vermiculite was injected into the pleural cavity of rats. Mesotheliomata developed in 48% of the rats treated with asbestos. No tumours occurred which were associated with the vermiculite injections.

Eradication of Tyzzer's disease in a colony of barrier-maintained mice

An outbreak of Tyzzer's disease in a large mouse colony is described. Tetracycline chemotherapy resulted in the control and apparent eradication of the disease.