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Thoracic lymphatic cannulation for the study of pulmonary immune responses in lung lymph of calves
1995
Gershwin, L.J. | Gunther, R.A. | Smith, S.G. | Boyle, G.A. | Friebertshauser, K.E.
Objective-To develop a system for analysis of immune response variables in the lymph draining the lung and to establish baseline data for clinically normal calves. Design-Surgery was performed on 6 calves to insert a cannula into the efferent lymphatic duct of the caudal mediastinal lymph node to create a long-term thoracic lymph fistula draining to the exterior. Lymph was collected daily, and on the fifth postoperative day, calves were exposed to an aerosol of cell culture medium (mock infection). For the next 10 days, lymph was collected for analysis and, on the tenth day, necropsy was performed. Animals-Six 6- to 8-week-old Holstein bull calves. Procedure-Daily lymph samples were evaluated for: flow rate; total and differential cell counts; and IgG, IgM, IgA, IgE, and protein concentrations. On days -4, -1, 1, 4, 7, and 10, cells were stained and quantitated by fluorescence-activated cell sorter analysis for T, B, CD4+, and CD8+ cells. Blood lymphocytes were evaluated on days -1 and 10 for comparison. Results-Flow was established for up to 25 days, with a mean rate between 11 and 22 ml/h. Protein concentrations in lymph and plasma did not indicate a protein drain. Although mean lymphocyte counts reflected a slight gradual decrease in lymph lymphocytes, this effect was not apparent in every calf, nor was the effect seen in blood lymphocytes. There were no significant changes in IgG, IgM, IgA, or IgE concentration, with the exception of IgA concentration in 1 calf that developed an abscess at the cannulation site. The T-cell subset absolute numbers of CD4+ and CD8+ cells decreased slightly over time, but the CD4+-to-CD8+ cell ratio remained almost constant at near 2. Conclusion-Creation of a thoracic lymphatic fistula appears to be a useful technique for studying effects of lung infection on immunologic variables, with potential application to bacterial and viral respiratory tract diseases.
Mostrar más [+] Menos [-]Systemic and colonic venous plasma eicosanoid and endotoxin concentrations, and colonic venous serum tumor necrosis factor and interleukin-6 activities in horses during low-flow ischemia and reperfusion of the large colon
1995
Moore, R.M. | Muir, W.W. | Cawrse, M. | Bertone, A.L. | Beard, W.L.
Twenty-four horses were randomly allocated to 3 groups. Horses were anesthetized, subjected to a ventral midline celiotomy, and the large colon was exteriorized and instrumented. Group-1 horses served as sham-operated controls. Group-2 horses were subjected to 6 hours of low-flow colonic arterial ischemia, and group-3 horses were subjected to 3 hours of ischemia and 3 hours of reperfusion. Baseline (BL) samples were collected, then low-flow ischemia was induced by reducing ventral colonic arterial blood flow to 20% of BL. All horses were monitored for 6 hours after BL data were collected. Blood samples were collected from the colonic vein and main pulmonary artery (systemic venous [SV]) for measurement of plasma endotoxin, 6-keto prostaglandin F1alpha (6-kPG), thromboxane B2 (TXB2), and prostaglandin E2 (PGE2) concentrations. Tumor necrosis factor and interleukin-6 activities were measured in colonic venous (CV) serum samples. Data were analyzed, using two-was ANOVA, and post-hoc comparisons were made, using Dunnett's and Tukey's tests. Statistical significance was set at P < 0.05 Endotoxin was not detected in CV or SV plasma at any time. There was no detectable tumor necrosis factor or interleukin-6 activity in CV samples at any time. There were no differences at BL among groups for CV or SV 6-kPG, PGE2, or TXB2 concentrations, nor were there any changes across time in group-1 horses. Colonic venous 6-kPG concentration increased during ischemia in horses of groups 2 and 3; CV 6-kPG concentration peaked at 3 hours in group-3 horses, then decreased during reperfusion, but remained increased through 6 hours in group-2 horses. Systemic venous 6-kPG concentration increased during reperfusion in group-3 horses, but there were no changes in group-2 horses. Colonic venous PGE2 concentration increased during ischemia in horses of groups 2 and 3, and remained increased for the first hour of reperfusion in group-3 horses and for the 6-hour duration of ischemia in group-2 horses. There were no temporal alterations in SV PGE2 concentration. There was no difference in CV or SV TXB2 concentration among or within groups across time; however, there was a trend (P = 0.075) toward greater CV TXB2 concentration at 3.25 hours, compared with BL, in group-3 horses. Eicosanoid concentrations were significantly lower in SV, compared with CV plasma. Prostaglandin E2 and 6-kPG concentrations were approximately 3 to 8 and 5 to 10 times greater, respectively, in CV than in SV plasma. The increased concentrations of 6-kPG and PGE2 in CV plasma were likely attributable to their accumulation secondary to colonic ischemia. The increased values of these vasodilator eicosanoids may have a role in the reactive hyperemia observed during reperfusion. The increased 6-kPG concentration in SV plasma may represent spillover from the colonic vasculature, but more likely reflects systemic production.
Mostrar más [+] Menos [-]Electrofusion of zona-free mouse embryonic cells in electrolytes and their development in vitro
1995
Elsheikh, A.S. (Hokkaido Univ., Sapporo (Japan)) | Takahashi, Y. | Tanaka, H. | Hishinuma, M. | Kanagawa, H.
The influence of increasing the physical electrofusion parameters, direct current (DC) pulse strength, pulse duration, pulse number, alternating current (AC) voltage and alignment time, in electrolytes on the rates of fusion,degeneration and development of zona-free mouse 2-cell embryos were examined. Furthermore, the effects of physiological saline and mannitol as fusion media and various mouse strains were also evaluated. Dulbecco's phosphate-buffered saline (PBS) supplemented with 10% fetal calf serum was used as the main fusion solution. A significant increase in the rate of fusion (P0.05) was obtained by increasing pulse strength from 30 to 300 V/mm. The embryos fused at the pules strengths of 30 to 70 V/mm had significantly higher development rates to blastocysts compared with those fused at 100 to 300 V/mm (P0.05). There were no significant differences in the rates of fusion, degeneration and d development to blastocysts when the pulse duration was increased from 30 to 90 mu-sec. Although fusion rates were increased (P0.05) by increasing the pulse number up to 4, a significant decrease (P0.05) in development to blastocysts was observed when the pulse number was 5. Application of AC voltage prior to the DC pulse tended to increase the fusion rate (89.2-93.8%), compared with fusion with the DC pulse only (75.0%). Prolongation of alignment time from 5 to 15 sec had no effect on the fusion rate. Under the optimum conditions (2 pulses of DC of 7- V/mm, 70 mu-sec pulse duration and AC of 5 V/mm for 5 sec), no significant difference was obtained in the fusion and development rates in different mouse strains, nor were fusion and development rates significantly different among PBS, physiological saline and mannitol solutions (P0.05)
Mostrar más [+] Menos [-]Preliminary efficacy trial of cymelarsan in mice artificially infected with Trypanosoma brucei brucei isolated from a dog in Zambia
1995
Syakalima, M. (Hokkaido Univ., Sapporo (Japan)) | Yasuda, J. | Hashimoto, A.
An efficacy trial of Cymelarsan (R) on a Zambian strain of Trypanosoma brucei brucei was done. Twenty-five male mice were infected intraperitoneally with 10(6) of T. b. brucei isolated from a dog. Five groups of 5 mice were treated with 0 (control), 0.25, 0.5, 1.0 and 2.0 mg/kg cymelarsan, respectively. The target was to achieve aparasitaemia for 30 days post-treatment, euthanising those that remained parasitaemic or relapsed before then. The 0.25 and 0.5 mg/kg groups remained parasitaemic although the parasitaemic levels were reduced. The 1.0 mg/kg group had a proportion of aparasitaemic mice. However, all mice in the 2.0 mg/kg group remained aparasitaemic until day 20 when 2 mice relapsed. These results suggested that more than 2.0 mg/kg was required to eliminate this strain
Mostrar más [+] Menos [-]Suspected nutritional myopathy in two captive Bennett's wallabies (Macropus rufogriseus)
1995
Braga, I.S. III (Hokkaido Univ., Sapporo (Japan)) | Tanaka, S. | Ochiai, K. | Itakura, C.
Between January and april, 1992, two captive Bennett's wallabies (Macropus rufogriseus) from a wildlife park in Iwamizawa City, Hokkaido, Japan, were diagnosed as having nutritional myopathy. One wallaby, four-year-old adult male, had mild fresh lesions, confined to the skeletal muscles, with poor cell reaction. The other wallaby, 8-month-old female joey, had marked and extensive lesions with cellular reactions and regenerative muscle fibers in the locomotor muscles. Involvement of other striated muscles such as those of the tongue, diaphragm and heart was mild with minimal cellular reaction. Age susceptibility may account for the difference in the extent of severity of the lesions between these two animals
Mostrar más [+] Menos [-]Expression of the endogenous Marek's disease virus ICP4 homolog (MDV ICP4) gene is enhanced in latently infected cells by transient transfection with the recombinant MDV ICP4 gene
1995
Endoh, D. (Hokkaido Univ., Sapporo (Japan)) | Ikegawa, S. | Kon, Y. | Hayashi, M. | Sato, F.
The ICP4 homolog of Marek's disease virus (MDV ICP4) is a possible candidate for the transactivator of the early genes. We transfected MDCC-MSB-1 (MSB-1) tumor cells with plasmid including a coding region of MDV ICP4 using cationic liposome. As carriers for intranulear transport, high mobility group -1 and -2 proteins were bound to the plasmid DNA before forming liposomes. We detected transcripts from the plasmid 2 hr after transfection by quantitative reverse-transcriptase polymerase chain reaction (RT-PCR) analysis. We also detected abundant transcripts of endogenous ICP4 2-96 hr after transfection. These data suggested that expression of introduced MDV ICP4 gene enhanced the expression of endogenous MDV ICP4. On the other hand, quantitative PCR analysis for virus genome DNA indicated no significant alteration of copy number of virus genome in transfected MSB-1 cells, suggesting that reactivation of virus requires more than turning on MDV ICP4 gene
Mostrar más [+] Menos [-]Effects of supplementation of the maturation media with insulin on in vitro maturation and in vitro fertilization of bovine oocytes
1995
Matsui, M. (Hokkaido Univ., Sapporo (Japan)) | Takahashi, Y. | Hishinuma, M. | Kanagawa, H.
This study ws carried out to determine the effects of supplementation of the maturation media with insulin on in vitro maturation and fertilization of bovine oocytes. In Experiment 1, cumulus-intact bovine oocytes were cultured in a maturation medium (TCM-199 containing 10% fetal calf serum, 0.02 U/ml follicular stimulating hormone and 1 mu-g/ml estradiol-17beta) with or without insulin supplementation (10 mu-g/ml). The maturation and fertilization rates of oocytes and subsequent embryonic development to the blastocyst stage were not affected by the treatment with insulin in the presence of serum and the hormones during the maturation period. In Experiment 2, to avoid the effects of serum and the hormones, a serum- and hormone-free maturation medium (TCM-199 containing 1 mg/ml polyvinyl alcohol) was used. In the absence of serum and hormones during the maturation period, the maturation rate was not affected by treatment with insulin, but the fertilization rate was improved. In Experiment 3, when denuded oocytes were inseminated together with cumulus cells cultured in serum- and hormone-free maturation medium supplemented with insulin, the fertilization rate was increased. These results demonstrate that the addition of insulin to the serum- and hormone-free maturation medium improves the fertilization rate of bovine oocytes in vitro, and suggest that insulin may stimulate the secretion of sperm capacitating agent(s) from cumulus cells
Mostrar más [+] Menos [-]Causes of calf mortality in Kabete area of Kenya
1995
Mulei, C.M. (Nairobi Univ. (Kenya). Dept. of Clinical Studies) | Gitau, G.K. | Mbuthia, P.G.
The use of preserved colostrum for rearing replacement dairy calves: calf performance, economics and on-farm practicability in Kenya
1995
Karioki, D.I. (Nairobi Univ. (Kenya). Dept. of Clinical Studies) | Gitau, G.K. | Munyua, S.J.M.
Pentastomid parasites of the family Sebekidae Fain, 1961 in West African dwarf crocodiles Osteolaemus tetraspis Cope, 1851 from the Congo, with a description of Alofia parva n. sp.
1995
Riley, J. (The Univ., Dundee, Scotland (United Kingdom). Dept. of Biological Sciences) | Huchzermeyer, F.W.