Use of antigen-detection enzyme immunoassays in assessment of trypanotolerance in N'Dama cattle.

Antigen-detection enzyme immunoassays (ELISA) were used for the diagnosis of Trypanosoma vivax, T. congolense and T. brucei in N'Dama cattle in Gabon, Central Africa. The assays are based on monoclonal antibodies which recognise trypanosome antigens specific for each of the three species and animals were termed 'antigenaemic' when found positive by this technique but not found parasitaemic by the buffy coat technique. 148 one-year-old animals were exposed to a medium natural tsetse challenge and an average of 6 assays per animal were carried out over a 92-day period. Blood samples were routinely examined 11 times over this period and 28% of animals were detected as parasitaemic by the buffy coat technique. 90% of these were antigen-ELISA positive. More importantly, 40% of the animals with negative parasitological findings were also found to be antigenaemic. Parasitaemic animals with above-average packed-red-cell volume percent (PCV) values had 32% higher daily weight gains than those with below average, while antigenaemic animals showed no significant linkage between PCV values and weight gain. Thus only the 28% of animals with detectable parasitaemias could have been used for selection decisions based on PCV values. Antigenaemic animals grew at the same rate as negative animals and had 22% superior growth rates to parasitaemic animals. When antigenaemic animals were classified as having more ability to control parasite growth than parasitaemic animals, a significant sire effect suggested some possibility of a degree of genetic control being involved. Thus the ELISA could offer a practical possibility for selection of trypanotolerant animals based on infection criteria.     

Late-Onset Superficial Lymphatic Malformation: Report of a Case and Review of the Literature

BACKGROUND: Superficial lymphatic malformations are predominantly developmental malformations of infancy, but they may arise at any age. OBJECTIVE: To describe a patient with a late-onset superficial lymphatic malformation. METHODS: Case report and literature review. RESULTS: A 53-year-old woman was evaluated for a colored lesion that developed spontaneously on the anterior abdominal wall. The lesion was treated by surgical excision. Findings on histopathologic examination of the specimen were consistent with superficial lymphatic malformation. There was no recurrence of the lesion at 4 months after the operation. CONCLUSION: Superficial lymphatic malformations can develop in adults spontaneously without the presence of any predisposing condition. Because the majority of such late-onset malformations reported in the literature are localized lesions similar to the one in our patient, surgical removal with inclusion of subcutaneous tissue usually results in cure without recurrence.     

Effect of mating behavior on luteinizing hormone-releasing hormone release in female rabbits as monitored with push-pull cannulae

To examine the effect of mating behavior on luteinizing hormone-releasing hormone (LHRH) release, intact New Zealand female rabbits were implanted with push-pull cannulae (PPC) aimed at the tuberal region of the hypothalamus and perfused with modified Krebs-Ringer phosphate medium at 11-13 microliters/min. In the mating experiments, does (n = 10) were initially perfused for a control period of 60-170 min followed by a mating period (100-160 min) which included the introduction of the male rabbit for an average time period of 30 min. Two groups of LHRH release patterns were observed: positive and negative responders. In the positive LHRH responders (n = 5), a clear rapid increase in LHRH release following mounting by the male occurred with a significant increase in the mean LHRH release (1.83 +/- 0.33 to 3.27 +/- 0.80 pg/10 min, p less than 0.040), in the mean LHRH amplitude (1.97 +/- 0.46 to 4.33 +/- 1.29 pg, p less than 0.022) and in the amplitude of the largest LHRH pulse (2.13 +/- 0.43 to 7.58 +/- 3.65 pg, p less than 0.022). In the negative LHRH responders (n = 5), no changes in LHRH release were detected although all rabbits ovulated, with some becoming pregnant. It appears from histological analysis that the difference between these two patterns of responses following mating are due to different cannula placements. In the positive responders, the tip of the PPC was localized in the tuberal region whereas in the negative responders, the placements were more dorsal and, in some cases, anterior.(ABSTRACT TRUNCATED AT 250 WORDS)     

A rural nursing practicum: making it work.

Inciting the interest of baccalaureate students in the practice of nursing in a rural setting has been an ongoing challenge for many educators. The authors identify difficulties they encountered when attempting to involve students in a rural nursing practicum and delineate several strategies used to overcome these difficulties.     

Nigrostriatal pathway modulates striatum vulnerability to quinolinic acid.

This study evaluates the modulation of striatum vulnerability to quinolinic acid (QA) by the nitrostriatal projection. Unilateral lesioning of the substantia nigra with 6-hydroxydopamine markedly reduced the volume of striatal necrosis observed 3 days after local injection of quinolinic acid (150 nmol). This result is consistent with the concept that the nigrostriatal pathway potentiates the vulnerability of striatum to excitotoxic damage.     

Pretreatment of bone with osteoclasts affects phenotypic expression of osteoblast-like cells.

Implant surface morphology regulates osteoblast phenotypic expression. Osteoblast sensitivity to non-biologic surfaces suggests that native bone surface features may also affect osteoblast response. To test this, MG63 osteoblast-like cells were grown for 7 days on bovine cortical bone wafers pretreated with rat bone marrow osteoclasts for 0, 10 or 20 days. Response to osteoclast-treated surfaces was compared to the response of MG63 cells to titanium surfaces with smooth and rough microtopographies. Cell number, differentiation (alkaline phosphatase activity and osteocalcin levels), and local factors (PGE(2) and TGF-beta1) were measured in confluent cultures. Compared to culture on plastic, cell number was reduced on all three types of bone wafers; this effect was dose-dependent with increasing resorption of the surface. Alkaline phosphatase specific activity was increased (P相似文献